drm/amdkfd: Add skeleton H/W debugger module support

This patch adds the skeleton H/W debugger module support. This code
enables registration and unregistration of a single HSA process at a
time.

The module saves the process's pasid and use it to verify that only the
registered process is allowed to execute debugger operations through the
kernel driver.

v2: rename get_dbgmgr_mutex to kfd_get_dbgmgr_mutex to namespace it

Signed-off-by: Yair Shachar <yair.shachar@amd.com>
Signed-off-by: Oded Gabbay <oded.gabbay@gmail.com>

1 files changed, 135 insertions, 0 deletions

diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_dbgmgr.c b/drivers/gpu/drm/amd/amdkfd/kfd_dbgmgr.c
new file mode 100644
index 000000000000..959be983ac45
--- /dev/null
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_dbgmgr.c
@@ -0,0 +1,135 @@
+/*
+ * Copyright 2014 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * 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 COPYRIGHT HOLDER(S) OR AUTHOR(S) 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/types.h>
+#include <linux/kernel.h>
+#include <linux/log2.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/device.h>
+
+#include "kfd_priv.h"
+#include "cik_regs.h"
+#include "kfd_pm4_headers.h"
+#include "kfd_pm4_headers_diq.h"
+#include "kfd_dbgmgr.h"
+#include "kfd_dbgdev.h"
+
+static DEFINE_MUTEX(kfd_dbgmgr_mutex);
+
+struct mutex *kfd_get_dbgmgr_mutex(void)
+{
+	return &kfd_dbgmgr_mutex;
+}
+
+
+static void kfd_dbgmgr_uninitialize(struct kfd_dbgmgr *pmgr)
+{
+	BUG_ON(!pmgr);
+
+	kfree(pmgr->dbgdev);
+
+	pmgr->dbgdev = NULL;
+	pmgr->pasid = 0;
+	pmgr->dev = NULL;
+}
+
+void kfd_dbgmgr_destroy(struct kfd_dbgmgr *pmgr)
+{
+	if (pmgr != NULL) {
+		kfd_dbgmgr_uninitialize(pmgr);
+		kfree(pmgr);
+	}
+}
+
+bool kfd_dbgmgr_create(struct kfd_dbgmgr **ppmgr, struct kfd_dev *pdev)
+{
+	enum DBGDEV_TYPE type = DBGDEV_TYPE_DIQ;
+	struct kfd_dbgmgr *new_buff;
+
+	BUG_ON(pdev == NULL);
+	BUG_ON(!pdev->init_complete);
+
+	new_buff = kfd_alloc_struct(new_buff);
+	if (!new_buff) {
+		pr_err("amdkfd: Failed to allocate dbgmgr instance\n");
+		return false;
+	}
+
+	new_buff->pasid = 0;
+	new_buff->dev = pdev;
+	new_buff->dbgdev = kfd_alloc_struct(new_buff->dbgdev);
+	if (!new_buff->dbgdev) {
+		pr_err("amdkfd: Failed to allocate dbgdev instance\n");
+		kfree(new_buff);
+		return false;
+	}
+
+	/* get actual type of DBGDevice cpsch or not */
+	if (sched_policy == KFD_SCHED_POLICY_NO_HWS)
+		type = DBGDEV_TYPE_NODIQ;
+
+	kfd_dbgdev_init(new_buff->dbgdev, pdev, type);
+	*ppmgr = new_buff;
+
+	return true;
+}
+
+long kfd_dbgmgr_register(struct kfd_dbgmgr *pmgr, struct kfd_process *p)
+{
+	BUG_ON(!p || !pmgr || !pmgr->dbgdev);
+
+	if (pmgr->pasid != 0) {
+		pr_debug("H/W debugger is already active using pasid %d\n",
+				pmgr->pasid);
+		return -EBUSY;
+	}
+
+	/* remember pasid */
+	pmgr->pasid = p->pasid;
+
+	/* provide the pqm for diq generation */
+	pmgr->dbgdev->pqm = &p->pqm;
+
+	/* activate the actual registering */
+	pmgr->dbgdev->dbgdev_register(pmgr->dbgdev);
+
+	return 0;
+}
+
+long kfd_dbgmgr_unregister(struct kfd_dbgmgr *pmgr, struct kfd_process *p)
+{
+	BUG_ON(!p || !pmgr || !pmgr->dbgdev);
+
+	/* Is the requests coming from the already registered process? */
+	if (pmgr->pasid != p->pasid) {
+		pr_debug("H/W debugger is not registered by calling pasid %d\n",
+				p->pasid);
+		return -EINVAL;
+	}
+
+	pmgr->dbgdev->dbgdev_unregister(pmgr->dbgdev);
+
+	pmgr->pasid = 0;
+
+	return 0;
+}