snic: driver for Cisco SCSI HBA

Cisco has developed a new PCI HBA interface called sNIC, which stands for
SCSI NIC. This is a new storage feature supported on specialized network
adapter. The new PCI function provides a uniform host interface and abstracts
backend storage.

[jejb: fix up checkpatch errors]
Signed-off-by: Narsimhulu Musini <nmusini@cisco.com>
Signed-off-by: Sesidhar Baddela <sebaddel@cisco.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Odin.com>

1 files changed, 295 insertions, 0 deletions

diff --git a/drivers/scsi/snic/snic_res.c b/drivers/scsi/snic/snic_res.c
new file mode 100644
index 000000000000..b54912c8ca0c
--- /dev/null
+++ b/drivers/scsi/snic/snic_res.c
@@ -0,0 +1,295 @@
+/*
+ * Copyright 2014 Cisco Systems, Inc.  All rights reserved.
+ *
+ * This program is free software; you may redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/pci.h>
+
+#include "wq_enet_desc.h"
+#include "cq_enet_desc.h"
+#include "vnic_resource.h"
+#include "vnic_dev.h"
+#include "vnic_wq.h"
+#include "vnic_cq.h"
+#include "vnic_intr.h"
+#include "vnic_stats.h"
+#include "snic.h"
+
+int
+snic_get_vnic_config(struct snic *snic)
+{
+	struct vnic_snic_config *c = &snic->config;
+	int ret;
+
+#define GET_CONFIG(m) \
+	do { \
+		ret = svnic_dev_spec(snic->vdev, \
+				     offsetof(struct vnic_snic_config, m), \
+				     sizeof(c->m), \
+				     &c->m); \
+		if (ret) { \
+			SNIC_HOST_ERR(snic->shost, \
+				      "Error getting %s, %d\n", #m, ret); \
+			return ret; \
+		} \
+	} while (0)
+
+	GET_CONFIG(wq_enet_desc_count);
+	GET_CONFIG(maxdatafieldsize);
+	GET_CONFIG(intr_timer);
+	GET_CONFIG(intr_timer_type);
+	GET_CONFIG(flags);
+	GET_CONFIG(io_throttle_count);
+	GET_CONFIG(port_down_timeout);
+	GET_CONFIG(port_down_io_retries);
+	GET_CONFIG(luns_per_tgt);
+	GET_CONFIG(xpt_type);
+	GET_CONFIG(hid);
+
+	c->wq_enet_desc_count = min_t(u32,
+				      VNIC_SNIC_WQ_DESCS_MAX,
+				      max_t(u32,
+					    VNIC_SNIC_WQ_DESCS_MIN,
+					    c->wq_enet_desc_count));
+
+	c->wq_enet_desc_count = ALIGN(c->wq_enet_desc_count, 16);
+
+	c->maxdatafieldsize = min_t(u32,
+				    VNIC_SNIC_MAXDATAFIELDSIZE_MAX,
+				    max_t(u32,
+					  VNIC_SNIC_MAXDATAFIELDSIZE_MIN,
+					  c->maxdatafieldsize));
+
+	c->io_throttle_count = min_t(u32,
+				     VNIC_SNIC_IO_THROTTLE_COUNT_MAX,
+				     max_t(u32,
+					   VNIC_SNIC_IO_THROTTLE_COUNT_MIN,
+					   c->io_throttle_count));
+
+	c->port_down_timeout = min_t(u32,
+				     VNIC_SNIC_PORT_DOWN_TIMEOUT_MAX,
+				     c->port_down_timeout);
+
+	c->port_down_io_retries = min_t(u32,
+				     VNIC_SNIC_PORT_DOWN_IO_RETRIES_MAX,
+				     c->port_down_io_retries);
+
+	c->luns_per_tgt = min_t(u32,
+				VNIC_SNIC_LUNS_PER_TARGET_MAX,
+				max_t(u32,
+				      VNIC_SNIC_LUNS_PER_TARGET_MIN,
+				      c->luns_per_tgt));
+
+	c->intr_timer = min_t(u32, VNIC_INTR_TIMER_MAX, c->intr_timer);
+
+	SNIC_INFO("vNIC resources wq %d\n", c->wq_enet_desc_count);
+	SNIC_INFO("vNIC mtu %d intr timer %d\n",
+		  c->maxdatafieldsize,
+		  c->intr_timer);
+
+	SNIC_INFO("vNIC flags 0x%x luns per tgt %d\n",
+		  c->flags,
+		  c->luns_per_tgt);
+
+	SNIC_INFO("vNIC io throttle count %d\n", c->io_throttle_count);
+	SNIC_INFO("vNIC port down timeout %d port down io retries %d\n",
+		  c->port_down_timeout,
+		  c->port_down_io_retries);
+
+	SNIC_INFO("vNIC back end type = %d\n", c->xpt_type);
+	SNIC_INFO("vNIC hid = %d\n", c->hid);
+
+	return 0;
+}
+
+void
+snic_get_res_counts(struct snic *snic)
+{
+	snic->wq_count = svnic_dev_get_res_count(snic->vdev, RES_TYPE_WQ);
+	SNIC_BUG_ON(snic->wq_count == 0);
+	snic->cq_count = svnic_dev_get_res_count(snic->vdev, RES_TYPE_CQ);
+	SNIC_BUG_ON(snic->cq_count == 0);
+	snic->intr_count = svnic_dev_get_res_count(snic->vdev,
+						  RES_TYPE_INTR_CTRL);
+	SNIC_BUG_ON(snic->intr_count == 0);
+}
+
+void
+snic_free_vnic_res(struct snic *snic)
+{
+	unsigned int i;
+
+	for (i = 0; i < snic->wq_count; i++)
+		svnic_wq_free(&snic->wq[i]);
+
+	for (i = 0; i < snic->cq_count; i++)
+		svnic_cq_free(&snic->cq[i]);
+
+	for (i = 0; i < snic->intr_count; i++)
+		svnic_intr_free(&snic->intr[i]);
+}
+
+int
+snic_alloc_vnic_res(struct snic *snic)
+{
+	enum vnic_dev_intr_mode intr_mode;
+	unsigned int mask_on_assertion;
+	unsigned int intr_offset;
+	unsigned int err_intr_enable;
+	unsigned int err_intr_offset;
+	unsigned int i;
+	int ret;
+
+	intr_mode = svnic_dev_get_intr_mode(snic->vdev);
+
+	SNIC_INFO("vNIC interrupt mode: %s\n",
+		  ((intr_mode == VNIC_DEV_INTR_MODE_INTX) ?
+		   "Legacy PCI INTx" :
+		   ((intr_mode == VNIC_DEV_INTR_MODE_MSI) ?
+		    "MSI" :
+		    ((intr_mode == VNIC_DEV_INTR_MODE_MSIX) ?
+		     "MSI-X" : "Unknown"))));
+
+	/* only MSI-X is supported */
+	SNIC_BUG_ON(intr_mode != VNIC_DEV_INTR_MODE_MSIX);
+
+	SNIC_INFO("wq %d cq %d intr %d\n", snic->wq_count,
+		  snic->cq_count,
+		  snic->intr_count);
+
+
+	/* Allocate WQs used for SCSI IOs */
+	for (i = 0; i < snic->wq_count; i++) {
+		ret = svnic_wq_alloc(snic->vdev,
+				     &snic->wq[i],
+				     i,
+				     snic->config.wq_enet_desc_count,
+				     sizeof(struct wq_enet_desc));
+		if (ret)
+			goto error_cleanup;
+	}
+
+	/* CQ for each WQ */
+	for (i = 0; i < snic->wq_count; i++) {
+		ret = svnic_cq_alloc(snic->vdev,
+				     &snic->cq[i],
+				     i,
+				     snic->config.wq_enet_desc_count,
+				     sizeof(struct cq_enet_wq_desc));
+		if (ret)
+			goto error_cleanup;
+	}
+
+	SNIC_BUG_ON(snic->cq_count != 2 * snic->wq_count);
+	/* CQ for FW TO host */
+	for (i = snic->wq_count; i < snic->cq_count; i++) {
+		ret = svnic_cq_alloc(snic->vdev,
+				     &snic->cq[i],
+				     i,
+				     (snic->config.wq_enet_desc_count * 3),
+				     sizeof(struct snic_fw_req));
+		if (ret)
+			goto error_cleanup;
+	}
+
+	for (i = 0; i < snic->intr_count; i++) {
+		ret = svnic_intr_alloc(snic->vdev, &snic->intr[i], i);
+		if (ret)
+			goto error_cleanup;
+	}
+
+	/*
+	 * Init WQ Resources.
+	 * WQ[0 to n] points to CQ[0 to n-1]
+	 * firmware to host comm points to CQ[n to m+1]
+	 */
+	err_intr_enable = 1;
+	err_intr_offset = snic->err_intr_offset;
+
+	for (i = 0; i < snic->wq_count; i++) {
+		svnic_wq_init(&snic->wq[i],
+			      i,
+			      err_intr_enable,
+			      err_intr_offset);
+	}
+
+	for (i = 0; i < snic->cq_count; i++) {
+		intr_offset = i;
+
+		svnic_cq_init(&snic->cq[i],
+			      0 /* flow_control_enable */,
+			      1 /* color_enable */,
+			      0 /* cq_head */,
+			      0 /* cq_tail */,
+			      1 /* cq_tail_color */,
+			      1 /* interrupt_enable */,
+			      1 /* cq_entry_enable */,
+			      0 /* cq_message_enable */,
+			      intr_offset,
+			      0 /* cq_message_addr */);
+	}
+
+	/*
+	 * Init INTR resources
+	 * Assumption : snic is always in MSI-X mode
+	 */
+	SNIC_BUG_ON(intr_mode != VNIC_DEV_INTR_MODE_MSIX);
+	mask_on_assertion = 1;
+
+	for (i = 0; i < snic->intr_count; i++) {
+		svnic_intr_init(&snic->intr[i],
+				snic->config.intr_timer,
+				snic->config.intr_timer_type,
+				mask_on_assertion);
+	}
+
+	/* init the stats memory by making the first call here */
+	ret = svnic_dev_stats_dump(snic->vdev, &snic->stats);
+	if (ret) {
+		SNIC_HOST_ERR(snic->shost,
+			      "svnic_dev_stats_dump failed - x%x\n",
+			      ret);
+		goto error_cleanup;
+	}
+
+	/* Clear LIF stats */
+	svnic_dev_stats_clear(snic->vdev);
+	ret = 0;
+
+	return ret;
+
+error_cleanup:
+	snic_free_vnic_res(snic);
+
+	return ret;
+}
+
+void
+snic_log_q_error(struct snic *snic)
+{
+	unsigned int i;
+	u32 err_status;
+
+	for (i = 0; i < snic->wq_count; i++) {
+		err_status = ioread32(&snic->wq[i].ctrl->error_status);
+		if (err_status)
+			SNIC_HOST_ERR(snic->shost,
+				      "WQ[%d] error status %d\n",
+				      i,
+				      err_status);
+	}
+} /* end of snic_log_q_error */