diff options
Diffstat (limited to 'drivers/gpu/drm')
| -rw-r--r-- | drivers/gpu/drm/Kconfig | 2 | ||||
| -rw-r--r-- | drivers/gpu/drm/Makefile | 1 | ||||
| -rw-r--r-- | drivers/gpu/drm/xen/Kconfig | 30 | ||||
| -rw-r--r-- | drivers/gpu/drm/xen/Makefile | 16 | ||||
| -rw-r--r-- | drivers/gpu/drm/xen/xen_drm_front.c | 882 | ||||
| -rw-r--r-- | drivers/gpu/drm/xen/xen_drm_front.h | 188 | ||||
| -rw-r--r-- | drivers/gpu/drm/xen/xen_drm_front_cfg.c | 77 | ||||
| -rw-r--r-- | drivers/gpu/drm/xen/xen_drm_front_cfg.h | 37 | ||||
| -rw-r--r-- | drivers/gpu/drm/xen/xen_drm_front_conn.c | 115 | ||||
| -rw-r--r-- | drivers/gpu/drm/xen/xen_drm_front_conn.h | 27 | ||||
| -rw-r--r-- | drivers/gpu/drm/xen/xen_drm_front_evtchnl.c | 387 | ||||
| -rw-r--r-- | drivers/gpu/drm/xen/xen_drm_front_evtchnl.h | 81 | ||||
| -rw-r--r-- | drivers/gpu/drm/xen/xen_drm_front_gem.c | 314 | ||||
| -rw-r--r-- | drivers/gpu/drm/xen/xen_drm_front_gem.h | 43 | ||||
| -rw-r--r-- | drivers/gpu/drm/xen/xen_drm_front_gem_cma.c | 79 | ||||
| -rw-r--r-- | drivers/gpu/drm/xen/xen_drm_front_kms.c | 372 | ||||
| -rw-r--r-- | drivers/gpu/drm/xen/xen_drm_front_kms.h | 26 | ||||
| -rw-r--r-- | drivers/gpu/drm/xen/xen_drm_front_shbuf.c | 436 | ||||
| -rw-r--r-- | drivers/gpu/drm/xen/xen_drm_front_shbuf.h | 72 |
19 files changed, 3185 insertions, 0 deletions
diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig index deeefa7a1773..757825ac60df 100644 --- a/drivers/gpu/drm/Kconfig +++ b/drivers/gpu/drm/Kconfig @@ -289,6 +289,8 @@ source "drivers/gpu/drm/pl111/Kconfig" source "drivers/gpu/drm/tve200/Kconfig" +source "drivers/gpu/drm/xen/Kconfig" + # Keep legacy drivers last menuconfig DRM_LEGACY diff --git a/drivers/gpu/drm/Makefile b/drivers/gpu/drm/Makefile index 50093ff4479b..9d66657ea117 100644 --- a/drivers/gpu/drm/Makefile +++ b/drivers/gpu/drm/Makefile @@ -103,3 +103,4 @@ obj-$(CONFIG_DRM_MXSFB) += mxsfb/ obj-$(CONFIG_DRM_TINYDRM) += tinydrm/ obj-$(CONFIG_DRM_PL111) += pl111/ obj-$(CONFIG_DRM_TVE200) += tve200/ +obj-$(CONFIG_DRM_XEN) += xen/ diff --git a/drivers/gpu/drm/xen/Kconfig b/drivers/gpu/drm/xen/Kconfig new file mode 100644 index 000000000000..4f4abc91f3b6 --- /dev/null +++ b/drivers/gpu/drm/xen/Kconfig @@ -0,0 +1,30 @@ +config DRM_XEN + bool "DRM Support for Xen guest OS" + depends on XEN + help + Choose this option if you want to enable DRM support + for Xen. + +config DRM_XEN_FRONTEND + tristate "Para-virtualized frontend driver for Xen guest OS" + depends on DRM_XEN + depends on DRM + select DRM_KMS_HELPER + select VIDEOMODE_HELPERS + select XEN_XENBUS_FRONTEND + help + Choose this option if you want to enable a para-virtualized + frontend DRM/KMS driver for Xen guest OSes. + +config DRM_XEN_FRONTEND_CMA + bool "Use DRM CMA to allocate dumb buffers" + depends on DRM_XEN_FRONTEND + select DRM_KMS_CMA_HELPER + select DRM_GEM_CMA_HELPER + help + Use DRM CMA helpers to allocate display buffers. + This is useful for the use-cases when guest driver needs to + share or export buffers to other drivers which only expect + contiguous buffers. + Note: in this mode driver cannot use buffers allocated + by the backend. diff --git a/drivers/gpu/drm/xen/Makefile b/drivers/gpu/drm/xen/Makefile new file mode 100644 index 000000000000..352730dc6c13 --- /dev/null +++ b/drivers/gpu/drm/xen/Makefile @@ -0,0 +1,16 @@ +# SPDX-License-Identifier: GPL-2.0 OR MIT + +drm_xen_front-objs := xen_drm_front.o \ + xen_drm_front_kms.o \ + xen_drm_front_conn.o \ + xen_drm_front_evtchnl.o \ + xen_drm_front_shbuf.o \ + xen_drm_front_cfg.o + +ifeq ($(CONFIG_DRM_XEN_FRONTEND_CMA),y) + drm_xen_front-objs += xen_drm_front_gem_cma.o +else + drm_xen_front-objs += xen_drm_front_gem.o +endif + +obj-$(CONFIG_DRM_XEN_FRONTEND) += drm_xen_front.o diff --git a/drivers/gpu/drm/xen/xen_drm_front.c b/drivers/gpu/drm/xen/xen_drm_front.c new file mode 100644 index 000000000000..4a08b77f1c9e --- /dev/null +++ b/drivers/gpu/drm/xen/xen_drm_front.c @@ -0,0 +1,882 @@ +// SPDX-License-Identifier: GPL-2.0 OR MIT + +/* + * Xen para-virtual DRM device + * + * Copyright (C) 2016-2018 EPAM Systems Inc. + * + * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> + */ + +#include <drm/drmP.h> +#include <drm/drm_atomic_helper.h> +#include <drm/drm_crtc_helper.h> +#include <drm/drm_gem.h> +#include <drm/drm_gem_cma_helper.h> + +#include <linux/of_device.h> + +#include <xen/platform_pci.h> +#include <xen/xen.h> +#include <xen/xenbus.h> + +#include <xen/interface/io/displif.h> + +#include "xen_drm_front.h" +#include "xen_drm_front_cfg.h" +#include "xen_drm_front_evtchnl.h" +#include "xen_drm_front_gem.h" +#include "xen_drm_front_kms.h" +#include "xen_drm_front_shbuf.h" + +struct xen_drm_front_dbuf { + struct list_head list; + u64 dbuf_cookie; + u64 fb_cookie; + struct xen_drm_front_shbuf *shbuf; +}; + +static int dbuf_add_to_list(struct xen_drm_front_info *front_info, + struct xen_drm_front_shbuf *shbuf, u64 dbuf_cookie) +{ + struct xen_drm_front_dbuf *dbuf; + + dbuf = kzalloc(sizeof(*dbuf), GFP_KERNEL); + if (!dbuf) + return -ENOMEM; + + dbuf->dbuf_cookie = dbuf_cookie; + dbuf->shbuf = shbuf; + list_add(&dbuf->list, &front_info->dbuf_list); + return 0; +} + +static struct xen_drm_front_dbuf *dbuf_get(struct list_head *dbuf_list, + u64 dbuf_cookie) +{ + struct xen_drm_front_dbuf *buf, *q; + + list_for_each_entry_safe(buf, q, dbuf_list, list) + if (buf->dbuf_cookie == dbuf_cookie) + return buf; + + return NULL; +} + +static void dbuf_flush_fb(struct list_head *dbuf_list, u64 fb_cookie) +{ + struct xen_drm_front_dbuf *buf, *q; + + list_for_each_entry_safe(buf, q, dbuf_list, list) + if (buf->fb_cookie == fb_cookie) + xen_drm_front_shbuf_flush(buf->shbuf); +} + +static void dbuf_free(struct list_head *dbuf_list, u64 dbuf_cookie) +{ + struct xen_drm_front_dbuf *buf, *q; + + list_for_each_entry_safe(buf, q, dbuf_list, list) + if (buf->dbuf_cookie == dbuf_cookie) { + list_del(&buf->list); + xen_drm_front_shbuf_unmap(buf->shbuf); + xen_drm_front_shbuf_free(buf->shbuf); + kfree(buf); + break; + } +} + +static void dbuf_free_all(struct list_head *dbuf_list) +{ + struct xen_drm_front_dbuf *buf, *q; + + list_for_each_entry_safe(buf, q, dbuf_list, list) { + list_del(&buf->list); + xen_drm_front_shbuf_unmap(buf->shbuf); + xen_drm_front_shbuf_free(buf->shbuf); + kfree(buf); + } +} + +static struct xendispl_req * +be_prepare_req(struct xen_drm_front_evtchnl *evtchnl, u8 operation) +{ + struct xendispl_req *req; + + req = RING_GET_REQUEST(&evtchnl->u.req.ring, + evtchnl->u.req.ring.req_prod_pvt); + req->operation = operation; + req->id = evtchnl->evt_next_id++; + evtchnl->evt_id = req->id; + return req; +} + +static int be_stream_do_io(struct xen_drm_front_evtchnl *evtchnl, + struct xendispl_req *req) +{ + reinit_completion(&evtchnl->u.req.completion); + if (unlikely(evtchnl->state != EVTCHNL_STATE_CONNECTED)) + return -EIO; + + xen_drm_front_evtchnl_flush(evtchnl); + return 0; +} + +static int be_stream_wait_io(struct xen_drm_front_evtchnl *evtchnl) +{ + if (wait_for_completion_timeout(&evtchnl->u.req.completion, + msecs_to_jiffies(XEN_DRM_FRONT_WAIT_BACK_MS)) <= 0) + return -ETIMEDOUT; + + return evtchnl->u.req.resp_status; +} + +int xen_drm_front_mode_set(struct xen_drm_front_drm_pipeline *pipeline, + u32 x, u32 y, u32 width, u32 height, + u32 bpp, u64 fb_cookie) +{ + struct xen_drm_front_evtchnl *evtchnl; + struct xen_drm_front_info *front_info; + struct xendispl_req *req; + unsigned long flags; + int ret; + + front_info = pipeline->drm_info->front_info; + evtchnl = &front_info->evt_pairs[pipeline->index].req; + if (unlikely(!evtchnl)) + return -EIO; + + mutex_lock(&evtchnl->u.req.req_io_lock); + + spin_lock_irqsave(&front_info->io_lock, flags); + req = be_prepare_req(evtchnl, XENDISPL_OP_SET_CONFIG); + req->op.set_config.x = x; + req->op.set_config.y = y; + req->op.set_config.width = width; + req->op.set_config.height = height; + req->op.set_config.bpp = bpp; + req->op.set_config.fb_cookie = fb_cookie; + + ret = be_stream_do_io(evtchnl, req); + spin_unlock_irqrestore(&front_info->io_lock, flags); + + if (ret == 0) + ret = be_stream_wait_io(evtchnl); + + mutex_unlock(&evtchnl->u.req.req_io_lock); + return ret; +} + +static int be_dbuf_create_int(struct xen_drm_front_info *front_info, + u64 dbuf_cookie, u32 width, u32 height, + u32 bpp, u64 size, struct page **pages, + struct sg_table *sgt) +{ + struct xen_drm_front_evtchnl *evtchnl; + struct xen_drm_front_shbuf *shbuf; + struct xendispl_req *req; + struct xen_drm_front_shbuf_cfg buf_cfg; + unsigned long flags; + int ret; + + evtchnl = &front_info->evt_pairs[GENERIC_OP_EVT_CHNL].req; + if (unlikely(!evtchnl)) + return -EIO; + + memset(&buf_cfg, 0, sizeof(buf_cfg)); + buf_cfg.xb_dev = front_info->xb_dev; + buf_cfg.pages = pages; + buf_cfg.size = size; + buf_cfg.sgt = sgt; + buf_cfg.be_alloc = front_info->cfg.be_alloc; + + shbuf = xen_drm_front_shbuf_alloc(&buf_cfg); + if (!shbuf) + return -ENOMEM; + + ret = dbuf_add_to_list(front_info, shbuf, dbuf_cookie); + if (ret < 0) { + xen_drm_front_shbuf_free(shbuf); + return ret; + } + + mutex_lock(&evtchnl->u.req.req_io_lock); + + spin_lock_irqsave(&front_info->io_lock, flags); + req = be_prepare_req(evtchnl, XENDISPL_OP_DBUF_CREATE); + req->op.dbuf_create.gref_directory = + xen_drm_front_shbuf_get_dir_start(shbuf); + req->op.dbuf_create.buffer_sz = size; + req->op.dbuf_create.dbuf_cookie = dbuf_cookie; + req->op.dbuf_create.width = width; + req->op.dbuf_create.height = height; + req->op.dbuf_create.bpp = bpp; + if (buf_cfg.be_alloc) + req->op.dbuf_create.flags |= XENDISPL_DBUF_FLG_REQ_ALLOC; + + ret = be_stream_do_io(evtchnl, req); + spin_unlock_irqrestore(&front_info->io_lock, flags); + + if (ret < 0) + goto fail; + + ret = be_stream_wait_io(evtchnl); + if (ret < 0) + goto fail; + + ret = xen_drm_front_shbuf_map(shbuf); + if (ret < 0) + goto fail; + + mutex_unlock(&evtchnl->u.req.req_io_lock); + return 0; + +fail: + mutex_unlock(&evtchnl->u.req.req_io_lock); + dbuf_free(&front_info->dbuf_list, dbuf_cookie); + return ret; +} + +int xen_drm_front_dbuf_create_from_sgt(struct xen_drm_front_info *front_info, + u64 dbuf_cookie, u32 width, u32 height, + u32 bpp, u64 size, struct sg_table *sgt) +{ + return be_dbuf_create_int(front_info, dbuf_cookie, width, height, + bpp, size, NULL, sgt); +} + +int xen_drm_front_dbuf_create_from_pages(struct xen_drm_front_info *front_info, + u64 dbuf_cookie, u32 width, u32 height, + u32 bpp, u64 size, struct page **pages) +{ + return be_dbuf_create_int(front_info, dbuf_cookie, width, height, + bpp, size, pages, NULL); +} + +static int xen_drm_front_dbuf_destroy(struct xen_drm_front_info *front_info, + u64 dbuf_cookie) +{ + struct xen_drm_front_evtchnl *evtchnl; + struct xendispl_req *req; + unsigned long flags; + bool be_alloc; + int ret; + + evtchnl = &front_info->evt_pairs[GENERIC_OP_EVT_CHNL].req; + if (unlikely(!evtchnl)) + return -EIO; + + be_alloc = front_info->cfg.be_alloc; + + /* + * For the backend allocated buffer release references now, so backend + * can free the buffer. + */ + if (be_alloc) + dbuf_free(&front_info->dbuf_list, dbuf_cookie); + + mutex_lock(&evtchnl->u.req.req_io_lock); + + spin_lock_irqsave(&front_info->io_lock, flags); + req = be_prepare_req(evtchnl, XENDISPL_OP_DBUF_DESTROY); + req->op.dbuf_destroy.dbuf_cookie = dbuf_cookie; + + ret = be_stream_do_io(evtchnl, req); + spin_unlock_irqrestore(&front_info->io_lock, flags); + + if (ret == 0) + ret = be_stream_wait_io(evtchnl); + + /* + * Do this regardless of communication status with the backend: + * if we cannot remove remote resources remove what we can locally. + */ + if (!be_alloc) + dbuf_free(&front_info->dbuf_list, dbuf_cookie); + + mutex_unlock(&evtchnl->u.req.req_io_lock); + return ret; +} + +int xen_drm_front_fb_attach(struct xen_drm_front_info *front_info, + u64 dbuf_cookie, u64 fb_cookie, u32 width, + u32 height, u32 pixel_format) +{ + struct xen_drm_front_evtchnl *evtchnl; + struct xen_drm_front_dbuf *buf; + struct xendispl_req *req; + unsigned long flags; + int ret; + + evtchnl = &front_info->evt_pairs[GENERIC_OP_EVT_CHNL].req; + if (unlikely(!evtchnl)) + return -EIO; + + buf = dbuf_get(&front_info->dbuf_list, dbuf_cookie); + if (!buf) + return -EINVAL; + + buf->fb_cookie = fb_cookie; + + mutex_lock(&evtchnl->u.req.req_io_lock); + + spin_lock_irqsave(&front_info->io_lock, flags); + req = be_prepare_req(evtchnl, XENDISPL_OP_FB_ATTACH); + req->op.fb_attach.dbuf_cookie = dbuf_cookie; + req->op.fb_attach.fb_cookie = fb_cookie; + req->op.fb_attach.width = width; + req->op.fb_attach.height = height; + req->op.fb_attach.pixel_format = pixel_format; + + ret = be_stream_do_io(evtchnl, req); + spin_unlock_irqrestore(&front_info->io_lock, flags); + + if (ret == 0) + ret = be_stream_wait_io(evtchnl); + + mutex_unlock(&evtchnl->u.req.req_io_lock); + return ret; +} + +int xen_drm_front_fb_detach(struct xen_drm_front_info *front_info, + u64 fb_cookie) +{ + struct xen_drm_front_evtchnl *evtchnl; + struct xendispl_req *req; + unsigned long flags; + int ret; + + evtchnl = &front_info->evt_pairs[GENERIC_OP_EVT_CHNL].req; + if (unlikely(!evtchnl)) + return -EIO; + + mutex_lock(&evtchnl->u.req.req_io_lock); + + spin_lock_irqsave(&front_info->io_lock, flags); + req = be_prepare_req(evtchnl, XENDISPL_OP_FB_DETACH); + req->op.fb_detach.fb_cookie = fb_cookie; + + ret = be_stream_do_io(evtchnl, req); + spin_unlock_irqrestore(&front_info->io_lock, flags); + + if (ret == 0) + ret = be_stream_wait_io(evtchnl); + + mutex_unlock(&evtchnl->u.req.req_io_lock); + return ret; +} + +int xen_drm_front_page_flip(struct xen_drm_front_info *front_info, + int conn_idx, u64 fb_cookie) +{ + struct xen_drm_front_evtchnl *evtchnl; + struct xendispl_req *req; + unsigned long flags; + int ret; + + if (unlikely(conn_idx >= front_info->num_evt_pairs)) + return -EINVAL; + + dbuf_flush_fb(&front_info->dbuf_list, fb_cookie); + evtchnl = &front_info->evt_pairs[conn_idx].req; + + mutex_lock(&evtchnl->u.req.req_io_lock); + + spin_lock_irqsave(&front_info->io_lock, flags); + req = be_prepare_req(evtchnl, XENDISPL_OP_PG_FLIP); + req->op.pg_flip.fb_cookie = fb_cookie; + + ret = be_stream_do_io(evtchnl, req); + spin_unlock_irqrestore(&front_info->io_lock, flags); + + if (ret == 0) + ret = be_stream_wait_io(evtchnl); + + mutex_unlock(&evtchnl->u.req.req_io_lock); + return ret; +} + +void xen_drm_front_on_frame_done(struct xen_drm_front_info *front_info, + int conn_idx, u64 fb_cookie) +{ + struct xen_drm_front_drm_info *drm_info = front_info->drm_info; + + if (unlikely(conn_idx >= front_info->cfg.num_connectors)) + return; + + xen_drm_front_kms_on_frame_done(&drm_info->pipeline[conn_idx], + fb_cookie); +} + +static int xen_drm_drv_dumb_create(struct drm_file *filp, + struct drm_device *dev, + struct drm_mode_create_dumb *args) +{ + struct xen_drm_front_drm_info *drm_info = dev->dev_private; + struct drm_gem_object *obj; + int ret; + + /* + * Dumb creation is a two stage process: first we create a fully + * constructed GEM object which is communicated to the backend, and + * only after that we can create GEM's handle. This is done so, + * because of the possible races: once you create a handle it becomes + * immediately visible to user-space, so the latter can try accessing + * object without pages etc. + * For details also see drm_gem_handle_create + */ + args->pitch = DIV_ROUND_UP(args->width * args->bpp, 8); + args->size = args->pitch * args->height; + + obj = xen_drm_front_gem_create(dev, args->size); + if (IS_ERR_OR_NULL(obj)) { + ret = PTR_ERR(obj); + goto fail; + } + + /* + * In case of CONFIG_DRM_XEN_FRONTEND_CMA gem_obj is constructed + * via DRM CMA helpers and doesn't have ->pages allocated + * (xendrm_gem_get_pages will return NULL), but instead can provide + * sg table + */ + if (xen_drm_front_gem_get_pages(obj)) + ret = xen_drm_front_dbuf_create_from_pages(drm_info->front_info, + xen_drm_front_dbuf_to_cookie(obj), + args->width, args->height, args->bpp, + args->size, + xen_drm_front_gem_get_pages(obj)); + else + ret = xen_drm_front_dbuf_create_from_sgt(drm_info->front_info, + xen_drm_front_dbuf_to_cookie(obj), + args->width, args->height, args->bpp, + args->size, + xen_drm_front_gem_get_sg_table(obj)); + if (ret) + goto fail_backend; + + /* This is the tail of GEM object creation */ + ret = drm_gem_handle_create(filp, obj, &args->handle); + if (ret) + goto fail_handle; + + /* Drop reference from allocate - handle holds it now */ + drm_gem_object_put_unlocked(obj); + return 0; + +fail_handle: + xen_drm_front_dbuf_destroy(drm_info->front_info, + xen_drm_front_dbuf_to_cookie(obj)); +fail_backend: + /* drop reference from allocate */ + drm_gem_object_put_unlocked(obj); +fail: + DRM_ERROR("Failed to create dumb buffer: %d\n", ret); + return ret; +} + +static void xen_drm_drv_free_object_unlocked(struct drm_gem_object *obj) +{ + struct xen_drm_front_drm_info *drm_info = obj->dev->dev_private; + int idx; + + if (drm_dev_enter(obj->dev, &idx)) { + xen_drm_front_dbuf_destroy(drm_info->front_info, + xen_drm_front_dbuf_to_cookie(obj)); + drm_dev_exit(idx); + } else { + dbuf_free(&drm_info->front_info->dbuf_list, + xen_drm_front_dbuf_to_cookie(obj)); + } + + xen_drm_front_gem_free_object_unlocked(obj); +} + +static void xen_drm_drv_release(struct drm_device *dev) +{ + struct xen_drm_front_drm_info *drm_info = dev->dev_private; + struct xen_drm_front_info *front_info = drm_info->front_info; + + xen_drm_front_kms_fini(drm_info); + + drm_atomic_helper_shutdown(dev); + drm_mode_config_cleanup(dev); + + drm_dev_fini(dev); + kfree(dev); + + if (front_info->cfg.be_alloc) + xenbus_switch_state(front_info->xb_dev, + XenbusStateInitialising); + + kfree(drm_info); +} + +static const struct file_operations xen_drm_dev_fops = { + .owner = THIS_MODULE, + .open = drm_open, + .release = drm_release, + .unlocked_ioctl = drm_ioctl, +#ifdef CONFIG_COMPAT + .compat_ioctl = drm_compat_ioctl, +#endif + .poll = drm_poll, + .read = drm_read, + .llseek = no_llseek, +#ifdef CONFIG_DRM_XEN_FRONTEND_CMA + .mmap = drm_gem_cma_mmap, +#else + .mmap = xen_drm_front_gem_mmap, +#endif +}; + +static const struct vm_operations_struct xen_drm_drv_vm_ops = { + .open = drm_gem_vm_open, + .close = drm_gem_vm_close, +}; + +static struct drm_driver xen_drm_driver = { + .driver_features = DRIVER_GEM | DRIVER_MODESET | + DRIVER_PRIME | DRIVER_ATOMIC, + .release = xen_drm_drv_release, + .gem_vm_ops = &xen_drm_drv_vm_ops, + .gem_free_object_unlocked = xen_drm_drv_free_object_unlocked, + .prime_handle_to_fd = drm_gem_prime_handle_to_fd, + .prime_fd_to_handle = drm_gem_prime_fd_to_handle, + .gem_prime_import = drm_gem_prime_import, + .gem_prime_export = drm_gem_prime_export, + .gem_prime_import_sg_table = xen_drm_front_gem_import_sg_table, + .gem_prime_get_sg_table = xen_drm_front_gem_get_sg_table, + .dumb_create = xen_drm_drv_dumb_create, + .fops = &xen_drm_dev_fops, + .name = "xendrm-du", + .desc = "Xen PV DRM Display Unit", + .date = "20180221", + .major = 1, + .minor = 0, + +#ifdef CONFIG_DRM_XEN_FRONTEND_CMA + .gem_prime_vmap = drm_gem_cma_prime_vmap, + .gem_prime_vunmap = drm_gem_cma_prime_vunmap, + .gem_prime_mmap = drm_gem_cma_prime_mmap, +#else + .gem_prime_vmap = xen_drm_front_gem_prime_vmap, + .gem_prime_vunmap = xen_drm_front_gem_prime_vunmap, + .gem_prime_mmap = xen_drm_front_gem_prime_mmap, +#endif +}; + +static int xen_drm_drv_init(struct xen_drm_front_info *front_info) +{ + struct device *dev = &front_info->xb_dev->dev; + struct xen_drm_front_drm_info *drm_info; + struct drm_device *drm_dev; + int ret; + + DRM_INFO("Creating %s\n", xen_drm_driver.desc); + + drm_info = kzalloc(sizeof(*drm_info), GFP_KERNEL); + if (!drm_info) { + ret = -ENOMEM; + goto fail; + } + + drm_info->front_info = front_info; + front_info->drm_info = drm_info; + + drm_dev = drm_dev_alloc(&xen_drm_driver, dev); + if (!drm_dev) { + ret = -ENOMEM; + goto fail; + } + + drm_info->drm_dev = drm_dev; + + drm_dev->dev_private = drm_info; + + ret = xen_drm_front_kms_init(drm_info); + if (ret) { + DRM_ERROR("Failed to initialize DRM/KMS, ret %d\n", ret); + goto fail_modeset; + } + + ret = drm_dev_register(drm_dev, 0); + if (ret) + goto fail_register; + + DRM_INFO("Initialized %s %d.%d.%d %s on minor %d\n", + xen_drm_driver.name, xen_drm_driver.major, + xen_drm_driver.minor, xen_drm_driver.patchlevel, + xen_drm_driver.date, drm_dev->primary->index); + + return 0; + +fail_register: + drm_dev_unregister(drm_dev); +fail_modeset: + drm_kms_helper_poll_fini(drm_dev); + drm_mode_config_cleanup(drm_dev); +fail: + kfree(drm_info); + return ret; +} + +static void xen_drm_drv_fini(struct xen_drm_front_info *front_info) +{ + struct xen_drm_front_drm_info *drm_info = front_info->drm_info; + struct drm_device *dev; + + if (!drm_info) + return; + + dev = drm_info->drm_dev; + if (!dev) + return; + + /* Nothing to do if device is already unplugged */ + if (drm_dev_is_unplugged(dev)) + return; + + drm_kms_helper_poll_fini(dev); + drm_dev_unplug(dev); + + front_info->drm_info = NULL; + + xen_drm_front_evtchnl_free_all(front_info); + dbuf_free_all(&front_info->dbuf_list); + + /* + * If we are not using backend allocated buffers, then tell the + * backend we are ready to (re)initialize. Otherwise, wait for + * drm_driver.release. + */ + if (!front_info->cfg.be_alloc) + xenbus_switch_state(front_info->xb_dev, + XenbusStateInitialising); +} + +static int displback_initwait(struct xen_drm_front_info *front_info) +{ + struct xen_drm_front_cfg *cfg = &front_info->cfg; + int ret; + + cfg->front_info = front_info; + ret = xen_drm_front_cfg_card(front_info, cfg); + if (ret < 0) + return ret; + + DRM_INFO("Have %d conector(s)\n", cfg->num_connectors); + /* Create event channels for all connectors and publish */ + ret = xen_drm_front_evtchnl_create_all(front_info); + if (ret < 0) + return ret; + + return xen_drm_front_evtchnl_publish_all(front_info); +} + +static int displback_connect(struct xen_drm_front_info *front_info) +{ + xen_drm_front_evtchnl_set_state(front_info, EVTCHNL_STATE_CONNECTED); + return xen_drm_drv_init(front_info); +} + +static void displback_disconnect(struct xen_drm_front_info *front_info) +{ + if (!front_info->drm_info) + return; + + /* Tell the backend to wait until we release the DRM driver. */ + xenbus_switch_state(front_info->xb_dev, XenbusStateReconfiguring); + + xen_drm_drv_fini(front_info); +} + +static void displback_changed(struct xenbus_device *xb_dev, + enum xenbus_state backend_state) +{ + struct xen_drm_front_info *front_info = dev_get_drvdata(&xb_dev->dev); + int ret; + + DRM_DEBUG("Backend state is %s, front is %s\n", + xenbus_strstate(backend_state), + xenbus_strstate(xb_dev->state)); + + switch (backend_state) { + case XenbusStateReconfiguring: + /* fall through */ + case XenbusStateReconfigured: + /* fall through */ + case XenbusStateInitialised: + break; + + case XenbusStateInitialising: + if (xb_dev->state == XenbusStateReconfiguring) + break; + + /* recovering after backend unexpected closure */ + displback_disconnect(front_info); + break; + + case XenbusStateInitWait: + if (xb_dev->state == XenbusStateReconfiguring) + break; + + /* recovering after backend unexpected closure */ + displback_disconnect(front_info); + if (xb_dev->state != XenbusStateInitialising) + break; + + ret = displback_initwait(front_info); + if (ret < 0) + xenbus_dev_fatal(xb_dev, ret, "initializing frontend"); + else + xenbus_switch_state(xb_dev, XenbusStateInitialised); + break; + + case XenbusStateConnected: + if (xb_dev->state != XenbusStateInitialised) + break; + + ret = displback_connect(front_info); + if (ret < 0) { + displback_disconnect(front_info); + xenbus_dev_fatal(xb_dev, ret, "connecting backend"); + } else { + xenbus_switch_state(xb_dev, XenbusStateConnected); + } + break; + + case XenbusStateClosing: + /* + * in this state backend starts freeing resources, + * so let it go into closed state, so we can also + * remove ours + */ + break; + + case XenbusStateUnknown: + /* fall through */ + case XenbusStateClosed: + if (xb_dev->state == XenbusStateClosed) + break; + + displback_disconnect(front_info); + break; + } +} + +static int xen_drv_probe(struct xenbus_device *xb_dev, + const struct xenbus_device_id *id) +{ + struct xen_drm_front_info *front_info; + struct device *dev = &xb_dev->dev; + int ret; + + /* + * The device is not spawn from a device tree, so arch_setup_dma_ops + * is not called, thus leaving the device with dummy DMA ops. + * This makes the device return error on PRIME buffer import, which + * is not correct: to fix this call of_dma_configure() with a NULL + * node to set default DMA ops. + */ + dev->bus->force_dma = true; + dev->coherent_dma_mask = DMA_BIT_MASK(32); + ret = of_dma_configure(dev, NULL); + if (ret < 0) { + DRM_ERROR("Cannot setup DMA ops, ret %d", ret); + return ret; + } + + front_info = devm_kzalloc(&xb_dev->dev, + sizeof(*front_info), GFP_KERNEL); + if (!front_info) + return -ENOMEM; + + front_info->xb_dev = xb_dev; + spin_lock_init(&front_info->io_lock); + INIT_LIST_HEAD(&front_info->dbuf_list); + dev_set_drvdata(&xb_dev->dev, front_info); + + return xenbus_switch_state(xb_dev, XenbusStateInitialising); +} + +static int xen_drv_remove(struct xenbus_device *dev) +{ + struct xen_drm_front_info *front_info = dev_get_drvdata(&dev->dev); + int to = 100; + + xenbus_switch_state(dev, XenbusStateClosing); + + /* + * On driver removal it is disconnected from XenBus, + * so no backend state change events come via .otherend_changed + * callback. This prevents us from exiting gracefully, e.g. + * signaling the backend to free event channels, waiting for its + * state to change to XenbusStateClosed and cleaning at our end. + * Normally when front driver removed backend will finally go into + * XenbusStateInitWait state. + * + * Workaround: read backend's state manually and wait with time-out. + */ + while ((xenbus_read_unsigned(front_info->xb_dev->otherend, "state", + XenbusStateUnknown) != XenbusStateInitWait) && + to--) + msleep(10); + + if (!to) { + unsigned int state; + + state = xenbus_read_unsigned(front_info->xb_dev->otherend, + "state", XenbusStateUnknown); + DRM_ERROR("Backend state is %s while removing driver\n", + xenbus_strstate(state)); + } + + xen_drm_drv_fini(front_info); + xenbus_frontend_closed(dev); + return 0; +} + +static const struct xenbus_device_id xen_driver_ids[] = { + { XENDISPL_DRIVER_NAME }, + { "" } +}; + +static struct xenbus_driver xen_driver = { + .ids = xen_driver_ids, + .probe = xen_drv_probe, + .remove = xen_drv_remove, + .otherend_changed = displback_changed, +}; + +static int __init xen_drv_init(void) +{ + /* At the moment we only support case with XEN_PAGE_SIZE == PAGE_SIZE */ + if (XEN_PAGE_SIZE != PAGE_SIZE) { + DRM_ERROR(XENDISPL_DRIVER_NAME ": different kernel and Xen page sizes are not supported: XEN_PAGE_SIZE (%lu) != PAGE_SIZE (%lu)\n", + XEN_PAGE_SIZE, PAGE_SIZE); + return -ENODEV; + } + + if (!xen_domain()) + return -ENODEV; + + if (!xen_has_pv_devices()) + return -ENODEV; + + DRM_INFO("Registering XEN PV " XENDISPL_DRIVER_NAME "\n"); + return xenbus_register_frontend(&xen_driver); +} + +static void __exit xen_drv_fini(void) +{ + DRM_INFO("Unregistering XEN PV " XENDISPL_DRIVER_NAME "\n"); + xenbus_unregister_driver(&xen_driver); +} + +module_init(xen_drv_init); +module_exit(xen_drv_fini); + +MODULE_DESCRIPTION("Xen para-virtualized display device frontend"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("xen:" XENDISPL_DRIVER_NAME); diff --git a/drivers/gpu/drm/xen/xen_drm_front.h b/drivers/gpu/drm/xen/xen_drm_front.h new file mode 100644 index 000000000000..16554b2463d8 --- /dev/null +++ b/drivers/gpu/drm/xen/xen_drm_front.h @@ -0,0 +1,188 @@ +/* SPDX-License-Identifier: GPL-2.0 OR MIT */ + +/* + * Xen para-virtual DRM device + * + * Copyright (C) 2016-2018 EPAM Systems Inc. + * + * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> + */ + +#ifndef __XEN_DRM_FRONT_H_ +#define __XEN_DRM_FRONT_H_ + +#include <drm/drmP.h> +#include <drm/drm_simple_kms_helper.h> + +#include <linux/scatterlist.h> + +#include "xen_drm_front_cfg.h" + +/** + * DOC: Driver modes of operation in terms of display buffers used + * + * Depending on the requirements for the para-virtualized environment, namely + * requirements dictated by the accompanying DRM/(v)GPU drivers running in both + * host and guest environments, number of operating modes of para-virtualized + * display driver are supported: + * + * - display buffers can be allocated by either frontend driver or backend + * - display buffers can be allocated to be contiguous in memory or not + * + * Note! Frontend driver itself has no dependency on contiguous memory for + * its operation. + */ + +/** + * DOC: Buffers allocated by the frontend driver + * + * The below modes of operation are configured at compile-time via + * frontend driver's kernel configuration: + */ + +/** + * DOC: With GEM CMA helpers + * + * This use-case is useful when used with accompanying DRM/vGPU driver in + * guest domain which was designed to only work with contiguous buffers, + * e.g. DRM driver based on GEM CMA helpers: such drivers can only import + * contiguous PRIME buffers, thus requiring frontend driver to provide + * such. In order to implement this mode of operation para-virtualized + * frontend driver can be configured to use GEM CMA helpers. + */ + +/** + * DOC: Without GEM CMA helpers + * + * If accompanying drivers can cope with non-contiguous memory then, to + * lower pressure on CMA subsystem of the kernel, driver can allocate + * buffers from system memory. + * + * Note! If used with accompanying DRM/(v)GPU drivers this mode of operation + * may require IOMMU support on the platform, so accompanying DRM/vGPU + * hardware can still reach display buffer memory while importing PRIME + * buffers from the frontend driver. + */ + +/** + * DOC: Buffers allocated by the backend + * + * This mode of operation is run-time configured via guest domain configuration + * through XenStore entries. + * + * For systems which do not provide IOMMU support, but having specific + * requirements for display buffers it is possible to allocate such buffers + * at backend side and share those with the frontend. + * For example, if host domain is 1:1 mapped and has DRM/GPU hardware expecting + * physically contiguous memory, this allows implementing zero-copying + * use-cases. + * + * Note, while using this scenario the following should be considered: + * + * #. If guest domain dies then pages/grants received from the backend + * cannot be claimed back + * + * #. Misbehaving guest may send too many requests to the + * backend exhausting its grant references and memory + * (consider this from security POV) + */ + +/** + * DOC: Driver limitations + * + * #. Only primary plane without additional properties is supported. + * + * #. Only one video mode per connector supported which is configured + * via XenStore. + * + * #. All CRTCs operate at fixed frequency of 60Hz. + */ + +/* timeout in ms to wait for backend to respond */ +#define XEN_DRM_FRONT_WAIT_BACK_MS 3000 + +#ifndef GRANT_INVALID_REF +/* + * Note on usage of grant reference 0 as invalid grant reference: + * grant reference 0 is valid, but never exposed to a PV driver, + * because of the fact it is already in use/reserved by the PV console. + */ +#define GRANT_INVALID_REF 0 +#endif + +struct xen_drm_front_info { + struct xenbus_device *xb_dev; + struct xen_drm_front_drm_info *drm_info; + + /* to protect data between backend IO code and interrupt handler */ + spinlock_t io_lock; + + int num_evt_pairs; + struct xen_drm_front_evtchnl_pair *evt_pairs; + struct xen_drm_front_cfg cfg; + + /* display buffers */ + struct list_head dbuf_list; +}; + +struct xen_drm_front_drm_pipeline { + struct xen_drm_front_drm_info *drm_info; + + int index; + + struct drm_simple_display_pipe pipe; + + struct drm_connector conn; + /* These are only for connector mode checking */ + int width, height; + + struct drm_pending_vblank_event *pending_event; + + struct delayed_work pflip_to_worker; + + bool conn_connected; +}; + +struct xen_drm_front_drm_info { + struct xen_drm_front_info *front_info; + struct drm_device *drm_dev; + + struct xen_drm_front_drm_pipeline pipeline[XEN_DRM_FRONT_MAX_CRTCS]; +}; + +static inline u64 xen_drm_front_fb_to_cookie(struct drm_framebuffer *fb) +{ + return (u64)fb; +} + +static inline u64 xen_drm_front_dbuf_to_cookie(struct drm_gem_object *gem_obj) +{ + return (u64)gem_obj; +} + +int xen_drm_front_mode_set(struct xen_drm_front_drm_pipeline *pipeline, + u32 x, u32 y, u32 width, u32 height, + u32 bpp, u64 fb_cookie); + +int xen_drm_front_dbuf_create_from_sgt(struct xen_drm_front_info *front_info, + u64 dbuf_cookie, u32 width, u32 height, + u32 bpp, u64 size, struct sg_table *sgt); + +int xen_drm_front_dbuf_create_from_pages(struct xen_drm_front_info *front_info, + u64 dbuf_cookie, u32 width, u32 height, + u32 bpp, u64 size, struct page **pages); + +int xen_drm_front_fb_attach(struct xen_drm_front_info *front_info, + u64 dbuf_cookie, u64 fb_cookie, u32 width, + u32 height, u32 pixel_format); + +int xen_drm_front_fb_detach(struct xen_drm_front_info *front_info, + u64 fb_cookie); + +int xen_drm_front_page_flip(struct xen_drm_front_info *front_info, + int conn_idx, u64 fb_cookie); + +void xen_drm_front_on_frame_done(struct xen_drm_front_info *front_info, + int conn_idx, u64 fb_cookie); + +#endif /* __XEN_DRM_FRONT_H_ */ diff --git a/drivers/gpu/drm/xen/xen_drm_front_cfg.c b/drivers/gpu/drm/xen/xen_drm_front_cfg.c new file mode 100644 index 000000000000..5baf2b9de93c --- /dev/null +++ b/drivers/gpu/drm/xen/xen_drm_front_cfg.c @@ -0,0 +1,77 @@ +// SPDX-License-Identifier: GPL-2.0 OR MIT + +/* + * Xen para-virtual DRM device + * + * Copyright (C) 2016-2018 EPAM Systems Inc. + * + * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> + */ + +#include <drm/drmP.h> + +#include <linux/device.h> + +#include <xen/interface/io/displif.h> +#include <xen/xenbus.h> + +#include "xen_drm_front.h" +#include "xen_drm_front_cfg.h" + +static int cfg_connector(struct xen_drm_front_info *front_info, + struct xen_drm_front_cfg_connector *connector, + const char *path, int index) +{ + char *connector_path; + + connector_path = devm_kasprintf(&front_info->xb_dev->dev, + GFP_KERNEL, "%s/%d", path, index); + if (!connector_path) + return -ENOMEM; + + if (xenbus_scanf(XBT_NIL, connector_path, XENDISPL_FIELD_RESOLUTION, + "%d" XENDISPL_RESOLUTION_SEPARATOR "%d", + &connector->width, &connector->height) < 0) { + /* either no entry configured or wrong resolution set */ + connector->width = 0; + connector->height = 0; + return -EINVAL; + } + + connector->xenstore_path = connector_path; + + DRM_INFO("Connector %s: resolution %dx%d\n", + connector_path, connector->width, connector->height); + return 0; +} + +int xen_drm_front_cfg_card(struct xen_drm_front_info *front_info, + struct xen_drm_front_cfg *cfg) +{ + struct xenbus_device *xb_dev = front_info->xb_dev; + int ret, i; + + if (xenbus_read_unsigned(front_info->xb_dev->nodename, + XENDISPL_FIELD_BE_ALLOC, 0)) { + DRM_INFO("Backend can provide display buffers\n"); + cfg->be_alloc = true; + } + + cfg->num_connectors = 0; + for (i = 0; i < ARRAY_SIZE(cfg->connectors); i++) { + ret = cfg_connector(front_info, &cfg->connectors[i], + xb_dev->nodename, i); + if (ret < 0) + break; + cfg->num_connectors++; + } + + if (!cfg->num_connectors) { + DRM_ERROR("No connector(s) configured at %s\n", + xb_dev->nodename); + return -ENODEV; + } + + return 0; +} + diff --git a/drivers/gpu/drm/xen/xen_drm_front_cfg.h b/drivers/gpu/drm/xen/xen_drm_front_cfg.h new file mode 100644 index 000000000000..aa8490ba9146 --- /dev/null +++ b/drivers/gpu/drm/xen/xen_drm_front_cfg.h @@ -0,0 +1,37 @@ +/* SPDX-License-Identifier: GPL-2.0 OR MIT */ + +/* + * Xen para-virtual DRM device + * + * Copyright (C) 2016-2018 EPAM Systems Inc. + * + * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> + */ + +#ifndef __XEN_DRM_FRONT_CFG_H_ +#define __XEN_DRM_FRONT_CFG_H_ + +#include <linux/types.h> + +#define XEN_DRM_FRONT_MAX_CRTCS 4 + +struct xen_drm_front_cfg_connector { + int width; + int height; + char *xenstore_path; +}; + +struct xen_drm_front_cfg { + struct xen_drm_front_info *front_info; + /* number of connectors in this configuration */ + int num_connectors; + /* connector configurations */ + struct xen_drm_front_cfg_connector connectors[XEN_DRM_FRONT_MAX_CRTCS]; + /* set if dumb buffers are allocated externally on backend side */ + bool be_alloc; +}; + +int xen_drm_front_cfg_card(struct xen_drm_front_info *front_info, + struct xen_drm_front_cfg *cfg); + +#endif /* __XEN_DRM_FRONT_CFG_H_ */ diff --git a/drivers/gpu/drm/xen/xen_drm_front_conn.c b/drivers/gpu/drm/xen/xen_drm_front_conn.c new file mode 100644 index 000000000000..c91ae532fa55 --- /dev/null +++ b/drivers/gpu/drm/xen/xen_drm_front_conn.c @@ -0,0 +1,115 @@ +// SPDX-License-Identifier: GPL-2.0 OR MIT + +/* + * Xen para-virtual DRM device + * + * Copyright (C) 2016-2018 EPAM Systems Inc. + * + * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> + */ + +#include <drm/drm_atomic_helper.h> +#include <drm/drm_crtc_helper.h> + +#include <video/videomode.h> + +#include "xen_drm_front.h" +#include "xen_drm_front_conn.h" +#include "xen_drm_front_kms.h" + +static struct xen_drm_front_drm_pipeline * +to_xen_drm_pipeline(struct drm_connector *connector) +{ + return container_of(connector, struct xen_drm_front_drm_pipeline, conn); +} + +static const u32 plane_formats[] = { + DRM_FORMAT_RGB565, + DRM_FORMAT_RGB888, + DRM_FORMAT_XRGB8888, + DRM_FORMAT_ARGB8888, + DRM_FORMAT_XRGB4444, + DRM_FORMAT_ARGB4444, + DRM_FORMAT_XRGB1555, + DRM_FORMAT_ARGB1555, +}; + +const u32 *xen_drm_front_conn_get_formats(int *format_count) +{ + *format_count = ARRAY_SIZE(plane_formats); + return plane_formats; +} + +static int connector_detect(struct drm_connector *connector, + struct drm_modeset_acquire_ctx *ctx, + bool force) +{ + struct xen_drm_front_drm_pipeline *pipeline = + to_xen_drm_pipeline(connector); + + if (drm_dev_is_unplugged(connector->dev)) + pipeline->conn_connected = false; + + return pipeline->conn_connected ? connector_status_connected : + connector_status_disconnected; +} + +#define XEN_DRM_CRTC_VREFRESH_HZ 60 + +static int connector_get_modes(struct drm_connector *connector) +{ + struct xen_drm_front_drm_pipeline *pipeline = + to_xen_drm_pipeline(connector); + struct drm_display_mode *mode; + struct videomode videomode; + int width, height; + + mode = drm_mode_create(connector->dev); + if (!mode) + return 0; + + memset(&videomode, 0, sizeof(videomode)); + videomode.hactive = pipeline->width; + videomode.vactive = pipeline->height; + width = videomode.hactive + videomode.hfront_porch + + videomode.hback_porch + videomode.hsync_len; + height = videomode.vactive + videomode.vfront_porch + + videomode.vback_porch + videomode.vsync_len; + videomode.pixelclock = width * height * XEN_DRM_CRTC_VREFRESH_HZ; + mode->type = DRM_MODE_TYPE_PREFERRED | DRM_MODE_TYPE_DRIVER; + + drm_display_mode_from_videomode(&videomode, mode); + drm_mode_probed_add(connector, mode); + return 1; +} + +static const struct drm_connector_helper_funcs connector_helper_funcs = { + .get_modes = connector_get_modes, + .detect_ctx = connector_detect, +}; + +static const struct drm_connector_funcs connector_funcs = { + .dpms = drm_helper_connector_dpms, + .fill_modes = drm_helper_probe_single_connector_modes, + .destroy = drm_connector_cleanup, + .reset = drm_atomic_helper_connector_reset, + .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state, + .atomic_destroy_state = drm_atomic_helper_connector_destroy_state, +}; + +int xen_drm_front_conn_init(struct xen_drm_front_drm_info *drm_info, + struct drm_connector *connector) +{ + struct xen_drm_front_drm_pipeline *pipeline = + to_xen_drm_pipeline(connector); + + drm_connector_helper_add(connector, &connector_helper_funcs); + + pipeline->conn_connected = true; + + connector->polled = DRM_CONNECTOR_POLL_CONNECT | + DRM_CONNECTOR_POLL_DISCONNECT; + + return drm_connector_init(drm_info->drm_dev, connector, + &connector_funcs, DRM_MODE_CONNECTOR_VIRTUAL); +} diff --git a/drivers/gpu/drm/xen/xen_drm_front_conn.h b/drivers/gpu/drm/xen/xen_drm_front_conn.h new file mode 100644 index 000000000000..39de7cf5adbe --- /dev/null +++ b/drivers/gpu/drm/xen/xen_drm_front_conn.h @@ -0,0 +1,27 @@ +/* SPDX-License-Identifier: GPL-2.0 OR MIT */ + +/* + * Xen para-virtual DRM device + * + * Copyright (C) 2016-2018 EPAM Systems Inc. + * + * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> + */ + +#ifndef __XEN_DRM_FRONT_CONN_H_ +#define __XEN_DRM_FRONT_CONN_H_ + +#include <drm/drmP.h> +#include <drm/drm_crtc.h> +#include <drm/drm_encoder.h> + +#include <linux/wait.h> + +struct xen_drm_front_drm_info; + +int xen_drm_front_conn_init(struct xen_drm_front_drm_info *drm_info, + struct drm_connector *connector); + +const u32 *xen_drm_front_conn_get_formats(int *format_count); + +#endif /* __XEN_DRM_FRONT_CONN_H_ */ diff --git a/drivers/gpu/drm/xen/xen_drm_front_evtchnl.c b/drivers/gpu/drm/xen/xen_drm_front_evtchnl.c new file mode 100644 index 000000000000..945226a95e9b --- /dev/null +++ b/drivers/gpu/drm/xen/xen_drm_front_evtchnl.c @@ -0,0 +1,387 @@ +// SPDX-License-Identifier: GPL-2.0 OR MIT + +/* + * Xen para-virtual DRM device + * + * Copyright (C) 2016-2018 EPAM Systems Inc. + * + * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> + */ + +#include <drm/drmP.h> + +#include <linux/errno.h> +#include <linux/irq.h> + +#include <xen/xenbus.h> +#include <xen/events.h> +#include <xen/grant_table.h> + +#include "xen_drm_front.h" +#include "xen_drm_front_evtchnl.h" + +static irqreturn_t evtchnl_interrupt_ctrl(int irq, void *dev_id) +{ + struct xen_drm_front_evtchnl *evtchnl = dev_id; + struct xen_drm_front_info *front_info = evtchnl->front_info; + struct xendispl_resp *resp; + RING_IDX i, rp; + unsigned long flags; + + if (unlikely(evtchnl->state != EVTCHNL_STATE_CONNECTED)) + return IRQ_HANDLED; + + spin_lock_irqsave(&front_info->io_lock, flags); + +again: + rp = evtchnl->u.req.ring.sring->rsp_prod; + /* ensure we see queued responses up to rp */ + virt_rmb(); + + for (i = evtchnl->u.req.ring.rsp_cons; i != rp; i++) { + resp = RING_GET_RESPONSE(&evtchnl->u.req.ring, i); + if (unlikely(resp->id != evtchnl->evt_id)) + continue; + + switch (resp->operation) { + case XENDISPL_OP_PG_FLIP: + case XENDISPL_OP_FB_ATTACH: + case XENDISPL_OP_FB_DETACH: + case XENDISPL_OP_DBUF_CREATE: + case XENDISPL_OP_DBUF_DESTROY: + case XENDISPL_OP_SET_CONFIG: + evtchnl->u.req.resp_status = resp->status; + complete(&evtchnl->u.req.completion); + break; + + default: + DRM_ERROR("Operation %d is not supported\n", + resp->operation); + break; + } + } + + evtchnl->u.req.ring.rsp_cons = i; + + if (i != evtchnl->u.req.ring.req_prod_pvt) { + int more_to_do; + + RING_FINAL_CHECK_FOR_RESPONSES(&evtchnl->u.req.ring, + more_to_do); + if (more_to_do) + goto again; + } else { + evtchnl->u.req.ring.sring->rsp_event = i + 1; + } + + spin_unlock_irqrestore(&front_info->io_lock, flags); + return IRQ_HANDLED; +} + +static irqreturn_t evtchnl_interrupt_evt(int irq, void *dev_id) +{ + struct xen_drm_front_evtchnl *evtchnl = dev_id; + struct xen_drm_front_info *front_info = evtchnl->front_info; + struct xendispl_event_page *page = evtchnl->u.evt.page; + u32 cons, prod; + unsigned long flags; + + if (unlikely(evtchnl->state != EVTCHNL_STATE_CONNECTED)) + return IRQ_HANDLED; + + spin_lock_irqsave(&front_info->io_lock, flags); + + prod = page->in_prod; + /* ensure we see ring contents up to prod */ + virt_rmb(); + if (prod == page->in_cons) + goto out; + + for (cons = page->in_cons; cons != prod; cons++) { + struct xendispl_evt *event; + + event = &XENDISPL_IN_RING_REF(page, cons); + if (unlikely(event->id != evtchnl->evt_id++)) + continue; + + switch (event->type) { + case XENDISPL_EVT_PG_FLIP: + xen_drm_front_on_frame_done(front_info, evtchnl->index, + event->op.pg_flip.fb_cookie); + break; + } + } + page->in_cons = cons; + /* ensure ring contents */ + virt_wmb(); + +out: + spin_unlock_irqrestore(&front_info->io_lock, flags); + return IRQ_HANDLED; +} + +static void evtchnl_free(struct xen_drm_front_info *front_info, + struct xen_drm_front_evtchnl *evtchnl) +{ + unsigned long page = 0; + + if (evtchnl->type == EVTCHNL_TYPE_REQ) + page = (unsigned long)evtchnl->u.req.ring.sring; + else if (evtchnl->type == EVTCHNL_TYPE_EVT) + page = (unsigned long)evtchnl->u.evt.page; + if (!page) + return; + + evtchnl->state = EVTCHNL_STATE_DISCONNECTED; + + if (evtchnl->type == EVTCHNL_TYPE_REQ) { + /* release all who still waits for response if any */ + evtchnl->u.req.resp_status = -EIO; + complete_all(&evtchnl->u.req.completion); + } + + if (evtchnl->irq) + unbind_from_irqhandler(evtchnl->irq, evtchnl); + + if (evtchnl->port) + xenbus_free_evtchn(front_info->xb_dev, evtchnl->port); + + /* end access and free the page */ + if (evtchnl->gref != GRANT_INVALID_REF) + gnttab_end_foreign_access(evtchnl->gref, 0, page); + + memset(evtchnl, 0, sizeof(*evtchnl)); +} + +static int evtchnl_alloc(struct xen_drm_front_info *front_info, int index, + struct xen_drm_front_evtchnl *evtchnl, + enum xen_drm_front_evtchnl_type type) +{ + struct xenbus_device *xb_dev = front_info->xb_dev; + unsigned long page; + grant_ref_t gref; + irq_handler_t handler; + int ret; + + memset(evtchnl, 0, sizeof(*evtchnl)); + evtchnl->type = type; + evtchnl->index = index; + evtchnl->front_info = front_info; + evtchnl->state = EVTCHNL_STATE_DISCONNECTED; + evtchnl->gref = GRANT_INVALID_REF; + + page = get_zeroed_page(GFP_NOIO | __GFP_HIGH); + if (!page) { + ret = -ENOMEM; + goto fail; + } + + if (type == EVTCHNL_TYPE_REQ) { + struct xen_displif_sring *sring; + + init_completion(&evtchnl->u.req.completion); + mutex_init(&evtchnl->u.req.req_io_lock); + sring = (struct xen_displif_sring *)page; + SHARED_RING_INIT(sring); + FRONT_RING_INIT(&evtchnl->u.req.ring, sring, XEN_PAGE_SIZE); + + ret = xenbus_grant_ring(xb_dev, sring, 1, &gref); + if (ret < 0) { + evtchnl->u.req.ring.sring = NULL; + free_page(page); + goto fail; + } + + handler = evtchnl_interrupt_ctrl; + } else { + ret = gnttab_grant_foreign_access(xb_dev->otherend_id, + virt_to_gfn((void *)page), 0); + if (ret < 0) { + free_page(page); + goto fail; + } + + evtchnl->u.evt.page = (struct xendispl_event_page *)page; + gref = ret; + handler = evtchnl_interrupt_evt; + } + evtchnl->gref = gref; + + ret = xenbus_alloc_evtchn(xb_dev, &evtchnl->port); + if (ret < 0) + goto fail; + + ret = bind_evtchn_to_irqhandler(evtchnl->port, + handler, 0, xb_dev->devicetype, + evtchnl); + if (ret < 0) + goto fail; + + evtchnl->irq = ret; + return 0; + +fail: + DRM_ERROR("Failed to allocate ring: %d\n", ret); + return ret; +} + +int xen_drm_front_evtchnl_create_all(struct xen_drm_front_info *front_info) +{ + struct xen_drm_front_cfg *cfg; + int ret, conn; + + cfg = &front_info->cfg; + + front_info->evt_pairs = + kcalloc(cfg->num_connectors, + sizeof(struct xen_drm_front_evtchnl_pair), + GFP_KERNEL); + if (!front_info->evt_pairs) { + ret = -ENOMEM; + goto fail; + } + + for (conn = 0; conn < cfg->num_connectors; conn++) { + ret = evtchnl_alloc(front_info, conn, + &front_info->evt_pairs[conn].req, + EVTCHNL_TYPE_REQ); + if (ret < 0) { + DRM_ERROR("Error allocating control channel\n"); + goto fail; + } + + ret = evtchnl_alloc(front_info, conn, + &front_info->evt_pairs[conn].evt, + EVTCHNL_TYPE_EVT); + if (ret < 0) { + DRM_ERROR("Error allocating in-event channel\n"); + goto fail; + } + } + front_info->num_evt_pairs = cfg->num_connectors; + return 0; + +fail: + xen_drm_front_evtchnl_free_all(front_info); + return ret; +} + +static int evtchnl_publish(struct xenbus_transaction xbt, + struct xen_drm_front_evtchnl *evtchnl, + const char *path, const char *node_ring, + const char *node_chnl) +{ + struct xenbus_device *xb_dev = evtchnl->front_info->xb_dev; + int ret; + + /* write control channel ring reference */ + ret = xenbus_printf(xbt, path, node_ring, "%u", evtchnl->gref); + if (ret < 0) { + xenbus_dev_error(xb_dev, ret, "writing ring-ref"); + return ret; + } + + /* write event channel ring reference */ + ret = xenbus_printf(xbt, path, node_chnl, "%u", evtchnl->port); + if (ret < 0) { + xenbus_dev_error(xb_dev, ret, "writing event channel"); + return ret; + } + + return 0; +} + +int xen_drm_front_evtchnl_publish_all(struct xen_drm_front_info *front_info) +{ + struct xenbus_transaction xbt; + struct xen_drm_front_cfg *plat_data; + int ret, conn; + + plat_data = &front_info->cfg; + +again: + ret = xenbus_transaction_start(&xbt); + if (ret < 0) { + xenbus_dev_fatal(front_info->xb_dev, ret, + "starting transaction"); + return ret; + } + + for (conn = 0; conn < plat_data->num_connectors; conn++) { + ret = evtchnl_publish(xbt, &front_info->evt_pairs[conn].req, + plat_data->connectors[conn].xenstore_path, + XENDISPL_FIELD_REQ_RING_REF, + XENDISPL_FIELD_REQ_CHANNEL); + if (ret < 0) + goto fail; + + ret = evtchnl_publish(xbt, &front_info->evt_pairs[conn].evt, + plat_data->connectors[conn].xenstore_path, + XENDISPL_FIELD_EVT_RING_REF, + XENDISPL_FIELD_EVT_CHANNEL); + if (ret < 0) + goto fail; + } + + ret = xenbus_transaction_end(xbt, 0); + if (ret < 0) { + if (ret == -EAGAIN) + goto again; + + xenbus_dev_fatal(front_info->xb_dev, ret, + "completing transaction"); + goto fail_to_end; + } + + return 0; + +fail: + xenbus_transaction_end(xbt, 1); + +fail_to_end: + xenbus_dev_fatal(front_info->xb_dev, ret, "writing Xen store"); + return ret; +} + +void xen_drm_front_evtchnl_flush(struct xen_drm_front_evtchnl *evtchnl) +{ + int notify; + + evtchnl->u.req.ring.req_prod_pvt++; + RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(&evtchnl->u.req.ring, notify); + if (notify) + notify_remote_via_irq(evtchnl->irq); +} + +void xen_drm_front_evtchnl_set_state(struct xen_drm_front_info *front_info, + enum xen_drm_front_evtchnl_state state) +{ + unsigned long flags; + int i; + + if (!front_info->evt_pairs) + return; + + spin_lock_irqsave(&front_info->io_lock, flags); + for (i = 0; i < front_info->num_evt_pairs; i++) { + front_info->evt_pairs[i].req.state = state; + front_info->evt_pairs[i].evt.state = state; + } + spin_unlock_irqrestore(&front_info->io_lock, flags); +} + +void xen_drm_front_evtchnl_free_all(struct xen_drm_front_info *front_info) +{ + int i; + + if (!front_info->evt_pairs) + return; + + for (i = 0; i < front_info->num_evt_pairs; i++) { + evtchnl_free(front_info, &front_info->evt_pairs[i].req); + evtchnl_free(front_info, &front_info->evt_pairs[i].evt); + } + + kfree(front_info->evt_pairs); + front_info->evt_pairs = NULL; +} diff --git a/drivers/gpu/drm/xen/xen_drm_front_evtchnl.h b/drivers/gpu/drm/xen/xen_drm_front_evtchnl.h new file mode 100644 index 000000000000..b0af6994332b --- /dev/null +++ b/drivers/gpu/drm/xen/xen_drm_front_evtchnl.h @@ -0,0 +1,81 @@ +/* SPDX-License-Identifier: GPL-2.0 OR MIT */ + +/* + * Xen para-virtual DRM device + * + * Copyright (C) 2016-2018 EPAM Systems Inc. + * + * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> + */ + +#ifndef __XEN_DRM_FRONT_EVTCHNL_H_ +#define __XEN_DRM_FRONT_EVTCHNL_H_ + +#include <linux/completion.h> +#include <linux/types.h> + +#include <xen/interface/io/ring.h> +#include <xen/interface/io/displif.h> + +/* + * All operations which are not connector oriented use this ctrl event channel, + * e.g. fb_attach/destroy which belong to a DRM device, not to a CRTC. + */ +#define GENERIC_OP_EVT_CHNL 0 + +enum xen_drm_front_evtchnl_state { + EVTCHNL_STATE_DISCONNECTED, + EVTCHNL_STATE_CONNECTED, +}; + +enum xen_drm_front_evtchnl_type { + EVTCHNL_TYPE_REQ, + EVTCHNL_TYPE_EVT, +}; + +struct xen_drm_front_drm_info; + +struct xen_drm_front_evtchnl { + struct xen_drm_front_info *front_info; + int gref; + int port; + int irq; + int index; + enum xen_drm_front_evtchnl_state state; + enum xen_drm_front_evtchnl_type type; + /* either response id or incoming event id */ + u16 evt_id; + /* next request id or next expected event id */ + u16 evt_next_id; + union { + struct { + struct xen_displif_front_ring ring; + struct completion completion; + /* latest response status */ + int resp_status; + /* serializer for backend IO: request/response */ + struct mutex req_io_lock; + } req; + struct { + struct xendispl_event_page *page; + } evt; + } u; +}; + +struct xen_drm_front_evtchnl_pair { + struct xen_drm_front_evtchnl req; + struct xen_drm_front_evtchnl evt; +}; + +int xen_drm_front_evtchnl_create_all(struct xen_drm_front_info *front_info); + +int xen_drm_front_evtchnl_publish_all(struct xen_drm_front_info *front_info); + +void xen_drm_front_evtchnl_flush(struct xen_drm_front_evtchnl *evtchnl); + +void xen_drm_front_evtchnl_set_state(struct xen_drm_front_info *front_info, + enum xen_drm_front_evtchnl_state state); + +void xen_drm_front_evtchnl_free_all(struct xen_drm_front_info *front_info); + +#endif /* __XEN_DRM_FRONT_EVTCHNL_H_ */ diff --git a/drivers/gpu/drm/xen/xen_drm_front_gem.c b/drivers/gpu/drm/xen/xen_drm_front_gem.c new file mode 100644 index 000000000000..3b04a2269d7a --- /dev/null +++ b/drivers/gpu/drm/xen/xen_drm_front_gem.c @@ -0,0 +1,314 @@ +// SPDX-License-Identifier: GPL-2.0 OR MIT + +/* + * Xen para-virtual DRM device + * + * Copyright (C) 2016-2018 EPAM Systems Inc. + * + * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> + */ + +#include "xen_drm_front_gem.h" + +#include <drm/drmP.h> +#include <drm/drm_crtc_helper.h> +#include <drm/drm_fb_helper.h> +#include <drm/drm_gem.h> + +#include <linux/dma-buf.h> +#include <linux/scatterlist.h> +#include <linux/shmem_fs.h> + +#include <xen/balloon.h> + +#include "xen_drm_front.h" +#include "xen_drm_front_shbuf.h" + +struct xen_gem_object { + struct drm_gem_object base; + + size_t num_pages; + struct page **pages; + + /* set for buffers allocated by the backend */ + bool be_alloc; + + /* this is for imported PRIME buffer */ + struct sg_table *sgt_imported; +}; + +static inline struct xen_gem_object * +to_xen_gem_obj(struct drm_gem_object *gem_obj) +{ + return container_of(gem_obj, struct xen_gem_object, base); +} + +static int gem_alloc_pages_array(struct xen_gem_object *xen_obj, + size_t buf_size) +{ + xen_obj->num_pages = DIV_ROUND_UP(buf_size, PAGE_SIZE); + xen_obj->pages = kvmalloc_array(xen_obj->num_pages, + sizeof(struct page *), GFP_KERNEL); + return !xen_obj->pages ? -ENOMEM : 0; +} + +static void gem_free_pages_array(struct xen_gem_object *xen_obj) +{ + kvfree(xen_obj->pages); + xen_obj->pages = NULL; +} + +static struct xen_gem_object *gem_create_obj(struct drm_device *dev, + size_t size) +{ + struct xen_gem_object *xen_obj; + int ret; + + xen_obj = kzalloc(sizeof(*xen_obj), GFP_KERNEL); + if (!xen_obj) + return ERR_PTR(-ENOMEM); + + ret = drm_gem_object_init(dev, &xen_obj->base, size); + if (ret < 0) { + kfree(xen_obj); + return ERR_PTR(ret); + } + + return xen_obj; +} + +static struct xen_gem_object *gem_create(struct drm_device *dev, size_t size) +{ + struct xen_drm_front_drm_info *drm_info = dev->dev_private; + struct xen_gem_object *xen_obj; + int ret; + + size = round_up(size, PAGE_SIZE); + xen_obj = gem_create_obj(dev, size); + if (IS_ERR_OR_NULL(xen_obj)) + return xen_obj; + + if (drm_info->front_info->cfg.be_alloc) { + /* + * backend will allocate space for this buffer, so + * only allocate array of pointers to pages + */ + ret = gem_alloc_pages_array(xen_obj, size); + if (ret < 0) + goto fail; + + /* + * allocate ballooned pages which will be used to map + * grant references provided by the backend + */ + ret = alloc_xenballooned_pages(xen_obj->num_pages, + xen_obj->pages); + if (ret < 0) { + DRM_ERROR("Cannot allocate %zu ballooned pages: %d\n", + xen_obj->num_pages, ret); + gem_free_pages_array(xen_obj); + goto fail; + } + + xen_obj->be_alloc = true; + return xen_obj; + } + /* + * need to allocate backing pages now, so we can share those + * with the backend + */ + xen_obj->num_pages = DIV_ROUND_UP(size, PAGE_SIZE); + xen_obj->pages = drm_gem_get_pages(&xen_obj->base); + if (IS_ERR_OR_NULL(xen_obj->pages)) { + ret = PTR_ERR(xen_obj->pages); + xen_obj->pages = NULL; + goto fail; + } + + return xen_obj; + +fail: + DRM_ERROR("Failed to allocate buffer with size %zu\n", size); + return ERR_PTR(ret); +} + +struct drm_gem_object *xen_drm_front_gem_create(struct drm_device *dev, + size_t size) +{ + struct xen_gem_object *xen_obj; + + xen_obj = gem_create(dev, size); + if (IS_ERR_OR_NULL(xen_obj)) + return ERR_CAST(xen_obj); + + return &xen_obj->base; +} + +void xen_drm_front_gem_free_object_unlocked(struct drm_gem_object *gem_obj) +{ + struct xen_gem_object *xen_obj = to_xen_gem_obj(gem_obj); + + if (xen_obj->base.import_attach) { + drm_prime_gem_destroy(&xen_obj->base, xen_obj->sgt_imported); + gem_free_pages_array(xen_obj); + } else { + if (xen_obj->pages) { + if (xen_obj->be_alloc) { + free_xenballooned_pages(xen_obj->num_pages, + xen_obj->pages); + gem_free_pages_array(xen_obj); + } else { + drm_gem_put_pages(&xen_obj->base, + xen_obj->pages, true, false); + } + } + } + drm_gem_object_release(gem_obj); + kfree(xen_obj); +} + +struct page **xen_drm_front_gem_get_pages(struct drm_gem_object *gem_obj) +{ + struct xen_gem_object *xen_obj = to_xen_gem_obj(gem_obj); + + return xen_obj->pages; +} + +struct sg_table *xen_drm_front_gem_get_sg_table(struct drm_gem_object *gem_obj) +{ + struct xen_gem_object *xen_obj = to_xen_gem_obj(gem_obj); + + if (!xen_obj->pages) + return NULL; + + return drm_prime_pages_to_sg(xen_obj->pages, xen_obj->num_pages); +} + +struct drm_gem_object * +xen_drm_front_gem_import_sg_table(struct drm_device *dev, + struct dma_buf_attachment *attach, + struct sg_table *sgt) +{ + struct xen_drm_front_drm_info *drm_info = dev->dev_private; + struct xen_gem_object *xen_obj; + size_t size; + int ret; + + size = attach->dmabuf->size; + xen_obj = gem_create_obj(dev, size); + if (IS_ERR_OR_NULL(xen_obj)) + return ERR_CAST(xen_obj); + + ret = gem_alloc_pages_array(xen_obj, size); + if (ret < 0) + return ERR_PTR(ret); + + xen_obj->sgt_imported = sgt; + + ret = drm_prime_sg_to_page_addr_arrays(sgt, xen_obj->pages, + NULL, xen_obj->num_pages); + if (ret < 0) + return ERR_PTR(ret); + + /* + * N.B. Although we have an API to create display buffer from sgt + * we use pages API, because we still need those for GEM handling, + * e.g. for mapping etc. + */ + ret = xen_drm_front_dbuf_create_from_pages(drm_info->front_info, + xen_drm_front_dbuf_to_cookie(&xen_obj->base), + 0, 0, 0, size, + xen_obj->pages); + if (ret < 0) + return ERR_PTR(ret); + + DRM_DEBUG("Imported buffer of size %zu with nents %u\n", + size, sgt->nents); + + return &xen_obj->base; +} + +static int gem_mmap_obj(struct xen_gem_object *xen_obj, + struct vm_area_struct *vma) +{ + unsigned long addr = vma->vm_start; + int i; + + /* + * clear the VM_PFNMAP flag that was set by drm_gem_mmap(), and set the + * vm_pgoff (used as a fake buffer offset by DRM) to 0 as we want to map + * the whole buffer. + */ + vma->vm_flags &= ~VM_PFNMAP; + vma->vm_flags |= VM_MIXEDMAP; + vma->vm_pgoff = 0; + vma->vm_page_prot = + pgprot_writecombine(vm_get_page_prot(vma->vm_flags)); + + /* + * vm_operations_struct.fault handler will be called if CPU access + * to VM is here. For GPUs this isn't the case, because CPU + * doesn't touch the memory. Insert pages now, so both CPU and GPU are + * happy. + * FIXME: as we insert all the pages now then no .fault handler must + * be called, so don't provide one + */ + for (i = 0; i < xen_obj->num_pages; i++) { + int ret; + + ret = vm_insert_page(vma, addr, xen_obj->pages[i]); + if (ret < 0) { + DRM_ERROR("Failed to insert pages into vma: %d\n", ret); + return ret; + } + + addr += PAGE_SIZE; + } + return 0; +} + +int xen_drm_front_gem_mmap(struct file *filp, struct vm_area_struct *vma) +{ + struct xen_gem_object *xen_obj; + struct drm_gem_object *gem_obj; + int ret; + + ret = drm_gem_mmap(filp, vma); + if (ret < 0) + return ret; + + gem_obj = vma->vm_private_data; + xen_obj = to_xen_gem_obj(gem_obj); + return gem_mmap_obj(xen_obj, vma); +} + +void *xen_drm_front_gem_prime_vmap(struct drm_gem_object *gem_obj) +{ + struct xen_gem_object *xen_obj = to_xen_gem_obj(gem_obj); + + if (!xen_obj->pages) + return NULL; + + return vmap(xen_obj->pages, xen_obj->num_pages, + VM_MAP, pgprot_writecombine(PAGE_KERNEL)); +} + +void xen_drm_front_gem_prime_vunmap(struct drm_gem_object *gem_obj, + void *vaddr) +{ + vunmap(vaddr); +} + +int xen_drm_front_gem_prime_mmap(struct drm_gem_object *gem_obj, + struct vm_area_struct *vma) +{ + struct xen_gem_object *xen_obj; + int ret; + + ret = drm_gem_mmap_obj(gem_obj, gem_obj->size, vma); + if (ret < 0) + return ret; + + xen_obj = to_xen_gem_obj(gem_obj); + return gem_mmap_obj(xen_obj, vma); +} diff --git a/drivers/gpu/drm/xen/xen_drm_front_gem.h b/drivers/gpu/drm/xen/xen_drm_front_gem.h new file mode 100644 index 000000000000..55e531f5a763 --- /dev/null +++ b/drivers/gpu/drm/xen/xen_drm_front_gem.h @@ -0,0 +1,43 @@ +/* SPDX-License-Identifier: GPL-2.0 OR MIT */ + +/* + * Xen para-virtual DRM device + * + * Copyright (C) 2016-2018 EPAM Systems Inc. + * + * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> + */ + +#ifndef __XEN_DRM_FRONT_GEM_H +#define __XEN_DRM_FRONT_GEM_H + +#include <drm/drmP.h> + +struct drm_gem_object *xen_drm_front_gem_create(struct drm_device *dev, + size_t size); + +struct drm_gem_object * +xen_drm_front_gem_import_sg_table(struct drm_device *dev, + struct dma_buf_attachment *attach, + struct sg_table *sgt); + +struct sg_table *xen_drm_front_gem_get_sg_table(struct drm_gem_object *gem_obj); + +struct page **xen_drm_front_gem_get_pages(struct drm_gem_object *obj); + +void xen_drm_front_gem_free_object_unlocked(struct drm_gem_object *gem_obj); + +#ifndef CONFIG_DRM_XEN_FRONTEND_CMA + +int xen_drm_front_gem_mmap(struct file *filp, struct vm_area_struct *vma); + +void *xen_drm_front_gem_prime_vmap(struct drm_gem_object *gem_obj); + +void xen_drm_front_gem_prime_vunmap(struct drm_gem_object *gem_obj, + void *vaddr); + +int xen_drm_front_gem_prime_mmap(struct drm_gem_object *gem_obj, + struct vm_area_struct *vma); +#endif + +#endif /* __XEN_DRM_FRONT_GEM_H */ diff --git a/drivers/gpu/drm/xen/xen_drm_front_gem_cma.c b/drivers/gpu/drm/xen/xen_drm_front_gem_cma.c new file mode 100644 index 000000000000..ba30a4bc2a39 --- /dev/null +++ b/drivers/gpu/drm/xen/xen_drm_front_gem_cma.c @@ -0,0 +1,79 @@ +// SPDX-License-Identifier: GPL-2.0 OR MIT + +/* + * Xen para-virtual DRM device + * + * Copyright (C) 2016-2018 EPAM Systems Inc. + * + * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> + */ + +#include <drm/drmP.h> +#include <drm/drm_gem.h> +#include <drm/drm_fb_cma_helper.h> +#include <drm/drm_gem_cma_helper.h> + +#include "xen_drm_front.h" +#include "xen_drm_front_gem.h" + +struct drm_gem_object * +xen_drm_front_gem_import_sg_table(struct drm_device *dev, + struct dma_buf_attachment *attach, + struct sg_table *sgt) +{ + struct xen_drm_front_drm_info *drm_info = dev->dev_private; + struct drm_gem_object *gem_obj; + struct drm_gem_cma_object *cma_obj; + int ret; + + gem_obj = drm_gem_cma_prime_import_sg_table(dev, attach, sgt); + if (IS_ERR_OR_NULL(gem_obj)) + return gem_obj; + + cma_obj = to_drm_gem_cma_obj(gem_obj); + + ret = xen_drm_front_dbuf_create_from_sgt(drm_info->front_info, + xen_drm_front_dbuf_to_cookie(gem_obj), + 0, 0, 0, gem_obj->size, + drm_gem_cma_prime_get_sg_table(gem_obj)); + if (ret < 0) + return ERR_PTR(ret); + + DRM_DEBUG("Imported CMA buffer of size %zu\n", gem_obj->size); + + return gem_obj; +} + +struct sg_table *xen_drm_front_gem_get_sg_table(struct drm_gem_object *gem_obj) +{ + return drm_gem_cma_prime_get_sg_table(gem_obj); +} + +struct drm_gem_object *xen_drm_front_gem_create(struct drm_device *dev, + size_t size) +{ + struct xen_drm_front_drm_info *drm_info = dev->dev_private; + struct drm_gem_cma_object *cma_obj; + + if (drm_info->front_info->cfg.be_alloc) { + /* This use-case is not yet supported and probably won't be */ + DRM_ERROR("Backend allocated buffers and CMA helpers are not supported at the same time\n"); + return ERR_PTR(-EINVAL); + } + + cma_obj = drm_gem_cma_create(dev, size); + if (IS_ERR_OR_NULL(cma_obj)) + return ERR_CAST(cma_obj); + + return &cma_obj->base; +} + +void xen_drm_front_gem_free_object_unlocked(struct drm_gem_object *gem_obj) +{ + drm_gem_cma_free_object(gem_obj); +} + +struct page **xen_drm_front_gem_get_pages(struct drm_gem_object *gem_obj) +{ + return NULL; +} diff --git a/drivers/gpu/drm/xen/xen_drm_front_kms.c b/drivers/gpu/drm/xen/xen_drm_front_kms.c new file mode 100644 index 000000000000..0bd6681fa4f3 --- /dev/null +++ b/drivers/gpu/drm/xen/xen_drm_front_kms.c @@ -0,0 +1,372 @@ +// SPDX-License-Identifier: GPL-2.0 OR MIT + +/* + * Xen para-virtual DRM device + * + * Copyright (C) 2016-2018 EPAM Systems Inc. + * + * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> + */ + +#include "xen_drm_front_kms.h" + +#include <drm/drmP.h> +#include <drm/drm_atomic.h> +#include <drm/drm_atomic_helper.h> +#include <drm/drm_crtc_helper.h> +#include <drm/drm_gem.h> +#include <drm/drm_gem_framebuffer_helper.h> + +#include "xen_drm_front.h" +#include "xen_drm_front_conn.h" + +/* + * Timeout in ms to wait for frame done event from the backend: + * must be a bit more than IO time-out + */ +#define FRAME_DONE_TO_MS (XEN_DRM_FRONT_WAIT_BACK_MS + 100) + +static struct xen_drm_front_drm_pipeline * +to_xen_drm_pipeline(struct drm_simple_display_pipe *pipe) +{ + return container_of(pipe, struct xen_drm_front_drm_pipeline, pipe); +} + +static void fb_destroy(struct drm_framebuffer *fb) +{ + struct xen_drm_front_drm_info *drm_info = fb->dev->dev_private; + int idx; + + if (drm_dev_enter(fb->dev, &idx)) { + xen_drm_front_fb_detach(drm_info->front_info, + xen_drm_front_fb_to_cookie(fb)); + drm_dev_exit(idx); + } + drm_gem_fb_destroy(fb); +} + +static struct drm_framebuffer_funcs fb_funcs = { + .destroy = fb_destroy, +}; + +static struct drm_framebuffer * +fb_create(struct drm_device *dev, struct drm_file *filp, + const struct drm_mode_fb_cmd2 *mode_cmd) +{ + struct xen_drm_front_drm_info *drm_info = dev->dev_private; + static struct drm_framebuffer *fb; + struct drm_gem_object *gem_obj; + int ret; + + fb = drm_gem_fb_create_with_funcs(dev, filp, mode_cmd, &fb_funcs); + if (IS_ERR_OR_NULL(fb)) + return fb; + + gem_obj = drm_gem_object_lookup(filp, mode_cmd->handles[0]); + if (!gem_obj) { + DRM_ERROR("Failed to lookup GEM object\n"); + ret = -ENOENT; + goto fail; + } + + drm_gem_object_put_unlocked(gem_obj); + + ret = xen_drm_front_fb_attach(drm_info->front_info, + xen_drm_front_dbuf_to_cookie(gem_obj), + xen_drm_front_fb_to_cookie(fb), + fb->width, fb->height, + fb->format->format); + if (ret < 0) { + DRM_ERROR("Back failed to attach FB %p: %d\n", fb, ret); + goto fail; + } + + return fb; + +fail: + drm_gem_fb_destroy(fb); + return ERR_PTR(ret); +} + +static const struct drm_mode_config_funcs mode_config_funcs = { + .fb_create = fb_create, + .atomic_check = drm_atomic_helper_check, + .atomic_commit = drm_atomic_helper_commit, +}; + +static void send_pending_event(struct xen_drm_front_drm_pipeline *pipeline) +{ + struct drm_crtc *crtc = &pipeline->pipe.crtc; + struct drm_device *dev = crtc->dev; + unsigned long flags; + + spin_lock_irqsave(&dev->event_lock, flags); + if (pipeline->pending_event) + drm_crtc_send_vblank_event(crtc, pipeline->pending_event); + pipeline->pending_event = NULL; + spin_unlock_irqrestore(&dev->event_lock, flags); +} + +static void display_enable(struct drm_simple_display_pipe *pipe, + struct drm_crtc_state *crtc_state, + struct drm_plane_state *plane_state) +{ + struct xen_drm_front_drm_pipeline *pipeline = + to_xen_drm_pipeline(pipe); + struct drm_crtc *crtc = &pipe->crtc; + struct drm_framebuffer *fb = plane_state->fb; + int ret, idx; + + if (!drm_dev_enter(pipe->crtc.dev, &idx)) + return; + + ret = xen_drm_front_mode_set(pipeline, crtc->x, crtc->y, + fb->width, fb->height, + fb->format->cpp[0] * 8, + xen_drm_front_fb_to_cookie(fb)); + + if (ret) { + DRM_ERROR("Failed to enable display: %d\n", ret); + pipeline->conn_connected = false; + } + + drm_dev_exit(idx); +} + +static void display_disable(struct drm_simple_display_pipe *pipe) +{ + struct xen_drm_front_drm_pipeline *pipeline = + to_xen_drm_pipeline(pipe); + int ret = 0, idx; + + if (drm_dev_enter(pipe->crtc.dev, &idx)) { + ret = xen_drm_front_mode_set(pipeline, 0, 0, 0, 0, 0, + xen_drm_front_fb_to_cookie(NULL)); + drm_dev_exit(idx); + } + if (ret) + DRM_ERROR("Failed to disable display: %d\n", ret); + + /* Make sure we can restart with enabled connector next time */ + pipeline->conn_connected = true; + + /* release stalled event if any */ + send_pending_event(pipeline); +} + +void xen_drm_front_kms_on_frame_done(struct xen_drm_front_drm_pipeline *pipeline, + u64 fb_cookie) +{ + /* + * This runs in interrupt context, e.g. under + * drm_info->front_info->io_lock, so we cannot call _sync version + * to cancel the work + */ + cancel_delayed_work(&pipeline->pflip_to_worker); + + send_pending_event(pipeline); +} + +static void pflip_to_worker(struct work_struct *work) +{ + struct delayed_work *delayed_work = to_delayed_work(work); + struct xen_drm_front_drm_pipeline *pipeline = + container_of(delayed_work, + struct xen_drm_front_drm_pipeline, + pflip_to_worker); + + DRM_ERROR("Frame done timed-out, releasing"); + send_pending_event(pipeline); +} + +static bool display_send_page_flip(struct drm_simple_display_pipe *pipe, + struct drm_plane_state *old_plane_state) +{ + struct drm_plane_state *plane_state = + drm_atomic_get_new_plane_state(old_plane_state->state, + &pipe->plane); + + /* + * If old_plane_state->fb is NULL and plane_state->fb is not, + * then this is an atomic commit which will enable display. + * If old_plane_state->fb is not NULL and plane_state->fb is, + * then this is an atomic commit which will disable display. + * Ignore these and do not send page flip as this framebuffer will be + * sent to the backend as a part of display_set_config call. + */ + if (old_plane_state->fb && plane_state->fb) { + struct xen_drm_front_drm_pipeline *pipeline = + to_xen_drm_pipeline(pipe); + struct xen_drm_front_drm_info *drm_info = pipeline->drm_info; + int ret; + + schedule_delayed_work(&pipeline->pflip_to_worker, + msecs_to_jiffies(FRAME_DONE_TO_MS)); + + ret = xen_drm_front_page_flip(drm_info->front_info, + pipeline->index, + xen_drm_front_fb_to_cookie(plane_state->fb)); + if (ret) { + DRM_ERROR("Failed to send page flip request to backend: %d\n", ret); + + pipeline->conn_connected = false; + /* + * Report the flip not handled, so pending event is + * sent, unblocking user-space. + */ + return false; + } + /* + * Signal that page flip was handled, pending event will be sent + * on frame done event from the backend. + */ + return true; + } + + return false; +} + +static int display_prepare_fb(struct drm_simple_display_pipe *pipe, + struct drm_plane_state *plane_state) +{ + return drm_gem_fb_prepare_fb(&pipe->plane, plane_state); +} + +static void display_update(struct drm_simple_display_pipe *pipe, + struct drm_plane_state *old_plane_state) +{ + struct xen_drm_front_drm_pipeline *pipeline = + to_xen_drm_pipeline(pipe); + struct drm_crtc *crtc = &pipe->crtc; + struct drm_pending_vblank_event *event; + int idx; + + event = crtc->state->event; + if (event) { + struct drm_device *dev = crtc->dev; + unsigned long flags; + + WARN_ON(pipeline->pending_event); + + spin_lock_irqsave(&dev->event_lock, flags); + crtc->state->event = NULL; + + pipeline->pending_event = event; + spin_unlock_irqrestore(&dev->event_lock, flags); + } + + if (!drm_dev_enter(pipe->crtc.dev, &idx)) { + send_pending_event(pipeline); + return; + } + + /* + * Send page flip request to the backend *after* we have event cached + * above, so on page flip done event from the backend we can + * deliver it and there is no race condition between this code and + * event from the backend. + * If this is not a page flip, e.g. no flip done event from the backend + * is expected, then send now. + */ + if (!display_send_page_flip(pipe, old_plane_state)) + send_pending_event(pipeline); + + drm_dev_exit(idx); +} + +static enum drm_mode_status +display_mode_valid(struct drm_crtc *crtc, const struct drm_display_mode *mode) +{ + struct xen_drm_front_drm_pipeline *pipeline = + container_of(crtc, struct xen_drm_front_drm_pipeline, + pipe.crtc); + + if (mode->hdisplay != pipeline->width) + return MODE_ERROR; + + if (mode->vdisplay != pipeline->height) + return MODE_ERROR; + + return MODE_OK; +} + +static const struct drm_simple_display_pipe_funcs display_funcs = { + .mode_valid = display_mode_valid, + .enable = display_enable, + .disable = display_disable, + .prepare_fb = display_prepare_fb, + .update = display_update, +}; + +static int display_pipe_init(struct xen_drm_front_drm_info *drm_info, + int index, struct xen_drm_front_cfg_connector *cfg, + struct xen_drm_front_drm_pipeline *pipeline) +{ + struct drm_device *dev = drm_info->drm_dev; + const u32 *formats; + int format_count; + int ret; + + pipeline->drm_info = drm_info; + pipeline->index = index; + pipeline->height = cfg->height; + pipeline->width = cfg->width; + + INIT_DELAYED_WORK(&pipeline->pflip_to_worker, pflip_to_worker); + + ret = xen_drm_front_conn_init(drm_info, &pipeline->conn); + if (ret) + return ret; + + formats = xen_drm_front_conn_get_formats(&format_count); + + return drm_simple_display_pipe_init(dev, &pipeline->pipe, + &display_funcs, formats, + format_count, NULL, + &pipeline->conn); +} + +int xen_drm_front_kms_init(struct xen_drm_front_drm_info *drm_info) +{ + struct drm_device *dev = drm_info->drm_dev; + int i, ret; + + drm_mode_config_init(dev); + + dev->mode_config.min_width = 0; + dev->mode_config.min_height = 0; + dev->mode_config.max_width = 4095; + dev->mode_config.max_height = 2047; + dev->mode_config.funcs = &mode_config_funcs; + + for (i = 0; i < drm_info->front_info->cfg.num_connectors; i++) { + struct xen_drm_front_cfg_connector *cfg = + &drm_info->front_info->cfg.connectors[i]; + struct xen_drm_front_drm_pipeline *pipeline = + &drm_info->pipeline[i]; + + ret = display_pipe_init(drm_info, i, cfg, pipeline); + if (ret) { + drm_mode_config_cleanup(dev); + return ret; + } + } + + drm_mode_config_reset(dev); + drm_kms_helper_poll_init(dev); + return 0; +} + +void xen_drm_front_kms_fini(struct xen_drm_front_drm_info *drm_info) +{ + int i; + + for (i = 0; i < drm_info->front_info->cfg.num_connectors; i++) { + struct xen_drm_front_drm_pipeline *pipeline = + &drm_info->pipeline[i]; + + cancel_delayed_work_sync(&pipeline->pflip_to_worker); + + send_pending_event(pipeline); + } +} diff --git a/drivers/gpu/drm/xen/xen_drm_front_kms.h b/drivers/gpu/drm/xen/xen_drm_front_kms.h new file mode 100644 index 000000000000..ab2fbad4fbbf --- /dev/null +++ b/drivers/gpu/drm/xen/xen_drm_front_kms.h @@ -0,0 +1,26 @@ +/* SPDX-License-Identifier: GPL-2.0 OR MIT */ + +/* + * Xen para-virtual DRM device + * + * Copyright (C) 2016-2018 EPAM Systems Inc. + * + * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> + */ + +#ifndef __XEN_DRM_FRONT_KMS_H_ +#define __XEN_DRM_FRONT_KMS_H_ + +#include <linux/types.h> + +struct xen_drm_front_drm_info; +struct xen_drm_front_drm_pipeline; + +int xen_drm_front_kms_init(struct xen_drm_front_drm_info *drm_info); + +void xen_drm_front_kms_fini(struct xen_drm_front_drm_info *drm_info); + +void xen_drm_front_kms_on_frame_done(struct xen_drm_front_drm_pipeline *pipeline, + u64 fb_cookie); + +#endif /* __XEN_DRM_FRONT_KMS_H_ */ diff --git a/drivers/gpu/drm/xen/xen_drm_front_shbuf.c b/drivers/gpu/drm/xen/xen_drm_front_shbuf.c new file mode 100644 index 000000000000..19914dde4b3d --- /dev/null +++ b/drivers/gpu/drm/xen/xen_drm_front_shbuf.c @@ -0,0 +1,436 @@ +// SPDX-License-Identifier: GPL-2.0 OR MIT + +/* + * Xen para-virtual DRM device + * + * Copyright (C) 2016-2018 EPAM Systems Inc. + * + * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> + */ + +#include <drm/drmP.h> + +#if defined(CONFIG_X86) +#include <drm/drm_cache.h> +#endif +#include <linux/errno.h> +#include <linux/mm.h> + +#include <asm/xen/hypervisor.h> +#include <xen/balloon.h> +#include <xen/xen.h> +#include <xen/xenbus.h> +#include <xen/interface/io/ring.h> +#include <xen/interface/io/displif.h> + +#include "xen_drm_front.h" +#include "xen_drm_front_shbuf.h" + +struct xen_drm_front_shbuf_ops { + /* + * Calculate number of grefs required to handle this buffer, + * e.g. if grefs are required for page directory only or the buffer + * pages as well. + */ + void (*calc_num_grefs)(struct xen_drm_front_shbuf *buf); + /* Fill page directory according to para-virtual display protocol. */ + void (*fill_page_dir)(struct xen_drm_front_shbuf *buf); + /* Claim grant references for the pages of the buffer. */ + int (*grant_refs_for_buffer)(struct xen_drm_front_shbuf *buf, + grant_ref_t *priv_gref_head, int gref_idx); + /* Map grant references of the buffer. */ + int (*map)(struct xen_drm_front_shbuf *buf); + /* Unmap grant references of the buffer. */ + int (*unmap)(struct xen_drm_front_shbuf *buf); +}; + +grant_ref_t xen_drm_front_shbuf_get_dir_start(struct xen_drm_front_shbuf *buf) +{ + if (!buf->grefs) + return GRANT_INVALID_REF; + + return buf->grefs[0]; +} + +int xen_drm_front_shbuf_map(struct xen_drm_front_shbuf *buf) +{ + if (buf->ops->map) + return buf->ops->map(buf); + + /* no need to map own grant references */ + return 0; +} + +int xen_drm_front_shbuf_unmap(struct xen_drm_front_shbuf *buf) +{ + if (buf->ops->unmap) + return buf->ops->unmap(buf); + + /* no need to unmap own grant references */ + return 0; +} + +void xen_drm_front_shbuf_flush(struct xen_drm_front_shbuf *buf) +{ +#if defined(CONFIG_X86) + drm_clflush_pages(buf->pages, buf->num_pages); +#endif +} + +void xen_drm_front_shbuf_free(struct xen_drm_front_shbuf *buf) +{ + if (buf->grefs) { + int i; + + for (i = 0; i < buf->num_grefs; i++) + if (buf->grefs[i] != GRANT_INVALID_REF) + gnttab_end_foreign_access(buf->grefs[i], + 0, 0UL); + } + kfree(buf->grefs); + kfree(buf->directory); + if (buf->sgt) { + sg_free_table(buf->sgt); + kvfree(buf->pages); + } + kfree(buf); +} + +/* + * number of grefs a page can hold with respect to the + * struct xendispl_page_directory header + */ +#define XEN_DRM_NUM_GREFS_PER_PAGE ((PAGE_SIZE - \ + offsetof(struct xendispl_page_directory, gref)) / \ + sizeof(grant_ref_t)) + +static int get_num_pages_dir(struct xen_drm_front_shbuf *buf) +{ + /* number of pages the page directory consumes itself */ + return DIV_ROUND_UP(buf->num_pages, XEN_DRM_NUM_GREFS_PER_PAGE); +} + +static void backend_calc_num_grefs(struct xen_drm_front_shbuf *buf) +{ + /* only for pages the page directory consumes itself */ + buf->num_grefs = get_num_pages_dir(buf); +} + +static void guest_calc_num_grefs(struct xen_drm_front_shbuf *buf) +{ + /* + * number of pages the page directory consumes itself + * plus grefs for the buffer pages + */ + buf->num_grefs = get_num_pages_dir(buf) + buf->num_pages; +} + +#define xen_page_to_vaddr(page) \ + ((phys_addr_t)pfn_to_kaddr(page_to_xen_pfn(page))) + +static int backend_unmap(struct xen_drm_front_shbuf *buf) +{ + struct gnttab_unmap_grant_ref *unmap_ops; + int i, ret; + + if (!buf->pages || !buf->backend_map_handles || !buf->grefs) + return 0; + + unmap_ops = kcalloc(buf->num_pages, sizeof(*unmap_ops), + GFP_KERNEL); + if (!unmap_ops) { + DRM_ERROR("Failed to get memory while unmapping\n"); + return -ENOMEM; + } + + for (i = 0; i < buf->num_pages; i++) { + phys_addr_t addr; + + addr = xen_page_to_vaddr(buf->pages[i]); + gnttab_set_unmap_op(&unmap_ops[i], addr, GNTMAP_host_map, + buf->backend_map_handles[i]); + } + + ret = gnttab_unmap_refs(unmap_ops, NULL, buf->pages, + buf->num_pages); + + for (i = 0; i < buf->num_pages; i++) { + if (unlikely(unmap_ops[i].status != GNTST_okay)) + DRM_ERROR("Failed to unmap page %d: %d\n", + i, unmap_ops[i].status); + } + + if (ret) + DRM_ERROR("Failed to unmap grant references, ret %d", ret); + + kfree(unmap_ops); + kfree(buf->backend_map_handles); + buf->backend_map_handles = NULL; + return ret; +} + +static int backend_map(struct xen_drm_front_shbuf *buf) +{ + struct gnttab_map_grant_ref *map_ops = NULL; + unsigned char *ptr; + int ret, cur_gref, cur_dir_page, cur_page, grefs_left; + + map_ops = kcalloc(buf->num_pages, sizeof(*map_ops), GFP_KERNEL); + if (!map_ops) + return -ENOMEM; + + buf->backend_map_handles = kcalloc(buf->num_pages, + sizeof(*buf->backend_map_handles), + GFP_KERNEL); + if (!buf->backend_map_handles) { + kfree(map_ops); + return -ENOMEM; + } + + /* + * read page directory to get grefs from the backend: for external + * buffer we only allocate buf->grefs for the page directory, + * so buf->num_grefs has number of pages in the page directory itself + */ + ptr = buf->directory; + grefs_left = buf->num_pages; + cur_page = 0; + for (cur_dir_page = 0; cur_dir_page < buf->num_grefs; cur_dir_page++) { + struct xendispl_page_directory *page_dir = + (struct xendispl_page_directory *)ptr; + int to_copy = XEN_DRM_NUM_GREFS_PER_PAGE; + + if (to_copy > grefs_left) + to_copy = grefs_left; + + for (cur_gref = 0; cur_gref < to_copy; cur_gref++) { + phys_addr_t addr; + + addr = xen_page_to_vaddr(buf->pages[cur_page]); + gnttab_set_map_op(&map_ops[cur_page], addr, + GNTMAP_host_map, + page_dir->gref[cur_gref], + buf->xb_dev->otherend_id); + cur_page++; + } + + grefs_left -= to_copy; + ptr += PAGE_SIZE; + } + ret = gnttab_map_refs(map_ops, NULL, buf->pages, buf->num_pages); + + /* save handles even if error, so we can unmap */ + for (cur_page = 0; cur_page < buf->num_pages; cur_page++) { + buf->backend_map_handles[cur_page] = map_ops[cur_page].handle; + if (unlikely(map_ops[cur_page].status != GNTST_okay)) + DRM_ERROR("Failed to map page %d: %d\n", + cur_page, map_ops[cur_page].status); + } + + if (ret) { + DRM_ERROR("Failed to map grant references, ret %d", ret); + backend_unmap(buf); + } + + kfree(map_ops); + return ret; +} + +static void backend_fill_page_dir(struct xen_drm_front_shbuf *buf) +{ + struct xendispl_page_directory *page_dir; + unsigned char *ptr; + int i, num_pages_dir; + + ptr = buf->directory; + num_pages_dir = get_num_pages_dir(buf); + + /* fill only grefs for the page directory itself */ + for (i = 0; i < num_pages_dir - 1; i++) { + page_dir = (struct xendispl_page_directory *)ptr; + + page_dir->gref_dir_next_page = buf->grefs[i + 1]; + ptr += PAGE_SIZE; + } + /* last page must say there is no more pages */ + page_dir = (struct xendispl_page_directory *)ptr; + page_dir->gref_dir_next_page = GRANT_INVALID_REF; +} + +static void guest_fill_page_dir(struct xen_drm_front_shbuf *buf) +{ + unsigned char *ptr; + int cur_gref, grefs_left, to_copy, i, num_pages_dir; + + ptr = buf->directory; + num_pages_dir = get_num_pages_dir(buf); + + /* + * while copying, skip grefs at start, they are for pages + * granted for the page directory itself + */ + cur_gref = num_pages_dir; + grefs_left = buf->num_pages; + for (i = 0; i < num_pages_dir; i++) { + struct xendispl_page_directory *page_dir = + (struct xendispl_page_directory *)ptr; + + if (grefs_left <= XEN_DRM_NUM_GREFS_PER_PAGE) { + to_copy = grefs_left; + page_dir->gref_dir_next_page = GRANT_INVALID_REF; + } else { + to_copy = XEN_DRM_NUM_GREFS_PER_PAGE; + page_dir->gref_dir_next_page = buf->grefs[i + 1]; + } + memcpy(&page_dir->gref, &buf->grefs[cur_gref], + to_copy * sizeof(grant_ref_t)); + ptr += PAGE_SIZE; + grefs_left -= to_copy; + cur_gref += to_copy; + } +} + +static int guest_grant_refs_for_buffer(struct xen_drm_front_shbuf *buf, + grant_ref_t *priv_gref_head, + int gref_idx) +{ + int i, cur_ref, otherend_id; + + otherend_id = buf->xb_dev->otherend_id; + for (i = 0; i < buf->num_pages; i++) { + cur_ref = gnttab_claim_grant_reference(priv_gref_head); + if (cur_ref < 0) + return cur_ref; + + gnttab_grant_foreign_access_ref(cur_ref, otherend_id, + xen_page_to_gfn(buf->pages[i]), + 0); + buf->grefs[gref_idx++] = cur_ref; + } + return 0; +} + +static int grant_references(struct xen_drm_front_shbuf *buf) +{ + grant_ref_t priv_gref_head; + int ret, i, j, cur_ref; + int otherend_id, num_pages_dir; + + ret = gnttab_alloc_grant_references(buf->num_grefs, &priv_gref_head); + if (ret < 0) { + DRM_ERROR("Cannot allocate grant references\n"); + return ret; + } + + otherend_id = buf->xb_dev->otherend_id; + j = 0; + num_pages_dir = get_num_pages_dir(buf); + for (i = 0; i < num_pages_dir; i++) { + unsigned long frame; + + cur_ref = gnttab_claim_grant_reference(&priv_gref_head); + if (cur_ref < 0) + return cur_ref; + + frame = xen_page_to_gfn(virt_to_page(buf->directory + + PAGE_SIZE * i)); + gnttab_grant_foreign_access_ref(cur_ref, otherend_id, frame, 0); + buf->grefs[j++] = cur_ref; + } + + if (buf->ops->grant_refs_for_buffer) { + ret = buf->ops->grant_refs_for_buffer(buf, &priv_gref_head, j); + if (ret) + return ret; + } + + gnttab_free_grant_references(priv_gref_head); + return 0; +} + +static int alloc_storage(struct xen_drm_front_shbuf *buf) +{ + if (buf->sgt) { + buf->pages = kvmalloc_array(buf->num_pages, + sizeof(struct page *), GFP_KERNEL); + if (!buf->pages) + return -ENOMEM; + + if (drm_prime_sg_to_page_addr_arrays(buf->sgt, buf->pages, + NULL, buf->num_pages) < 0) + return -EINVAL; + } + + buf->grefs = kcalloc(buf->num_grefs, sizeof(*buf->grefs), GFP_KERNEL); + if (!buf->grefs) + return -ENOMEM; + + buf->directory = kcalloc(get_num_pages_dir(buf), PAGE_SIZE, GFP_KERNEL); + if (!buf->directory) + return -ENOMEM; + + return 0; +} + +/* + * For be allocated buffers we don't need grant_refs_for_buffer as those + * grant references are allocated at backend side + */ +static const struct xen_drm_front_shbuf_ops backend_ops = { + .calc_num_grefs = backend_calc_num_grefs, + .fill_page_dir = backend_fill_page_dir, + .map = backend_map, + .unmap = backend_unmap +}; + +/* For locally granted references we do not need to map/unmap the references */ +static const struct xen_drm_front_shbuf_ops local_ops = { + .calc_num_grefs = guest_calc_num_grefs, + .fill_page_dir = guest_fill_page_dir, + .grant_refs_for_buffer = guest_grant_refs_for_buffer, +}; + +struct xen_drm_front_shbuf * +xen_drm_front_shbuf_alloc(struct xen_drm_front_shbuf_cfg *cfg) +{ + struct xen_drm_front_shbuf *buf; + int ret; + + /* either pages or sgt, not both */ + if (unlikely(cfg->pages && cfg->sgt)) { + DRM_ERROR("Cannot handle buffer allocation with both pages and sg table provided\n"); + return NULL; + } + + buf = kzalloc(sizeof(*buf), GFP_KERNEL); + if (!buf) + return NULL; + + if (cfg->be_alloc) + buf->ops = &backend_ops; + else + buf->ops = &local_ops; + + buf->xb_dev = cfg->xb_dev; + buf->num_pages = DIV_ROUND_UP(cfg->size, PAGE_SIZE); + buf->sgt = cfg->sgt; + buf->pages = cfg->pages; + + buf->ops->calc_num_grefs(buf); + + ret = alloc_storage(buf); + if (ret) + goto fail; + + ret = grant_references(buf); + if (ret) + goto fail; + + buf->ops->fill_page_dir(buf); + + return buf; + +fail: + xen_drm_front_shbuf_free(buf); + return ERR_PTR(ret); +} diff --git a/drivers/gpu/drm/xen/xen_drm_front_shbuf.h b/drivers/gpu/drm/xen/xen_drm_front_shbuf.h new file mode 100644 index 000000000000..8c037fd7608b --- /dev/null +++ b/drivers/gpu/drm/xen/xen_drm_front_shbuf.h @@ -0,0 +1,72 @@ +/* SPDX-License-Identifier: GPL-2.0 OR MIT */ + +/* + * Xen para-virtual DRM device + * + * Copyright (C) 2016-2018 EPAM Systems Inc. + * + * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> + */ + +#ifndef __XEN_DRM_FRONT_SHBUF_H_ +#define __XEN_DRM_FRONT_SHBUF_H_ + +#include <linux/kernel.h> +#include <linux/scatterlist.h> + +#include <xen/grant_table.h> + +struct xen_drm_front_shbuf { + /* + * number of references granted for the backend use: + * - for allocated/imported dma-buf's this holds number of grant + * references for the page directory and pages of the buffer + * - for the buffer provided by the backend this holds number of + * grant references for the page directory as grant references for + * the buffer will be provided by the backend + */ + int num_grefs; + grant_ref_t *grefs; + unsigned char *directory; + + /* + * there are 2 ways to provide backing storage for this shared buffer: + * either pages or sgt. if buffer created from sgt then we own + * the pages and must free those ourselves on closure + */ + int num_pages; + struct page **pages; + + struct sg_table *sgt; + + struct xenbus_device *xb_dev; + + /* these are the ops used internally depending on be_alloc mode */ + const struct xen_drm_front_shbuf_ops *ops; + + /* Xen map handles for the buffer allocated by the backend */ + grant_handle_t *backend_map_handles; +}; + +struct xen_drm_front_shbuf_cfg { + struct xenbus_device *xb_dev; + size_t size; + struct page **pages; + struct sg_table *sgt; + bool be_alloc; +}; + +struct xen_drm_front_shbuf * +xen_drm_front_shbuf_alloc(struct xen_drm_front_shbuf_cfg *cfg); + +grant_ref_t xen_drm_front_shbuf_get_dir_start(struct xen_drm_front_shbuf *buf); + +int xen_drm_front_shbuf_map(struct xen_drm_front_shbuf *buf); + +int xen_drm_front_shbuf_unmap(struct xen_drm_front_shbuf *buf); + +void xen_drm_front_shbuf_flush(struct xen_drm_front_shbuf *buf); + +void xen_drm_front_shbuf_free(struct xen_drm_front_shbuf *buf); + +#endif /* __XEN_DRM_FRONT_SHBUF_H_ */ |