drm/amdgpu: adding device coredump support

Added device coredump information:
- Kernel version
- Module
- Time
- VRAM status
- Guilty process name and PID
- GPU register dumps
v1 -> v2: Variable name change
v1 -> v2: NULL check
v1 -> v2: Code alignment
v1 -> v2: Adding dummy amdgpu_devcoredump_free
v1 -> v2: memset reset_task_info to zero
v2 -> v3: add CONFIG_DEV_COREDUMP for variables
v2 -> v3: remove NULL check on amdgpu_devcoredump_read
Signed-off-by: Somalapuram Amaranath <Amaranath.Somalapuram@amd.com>
Reviewed-by: Shashank Sharma <Shashank.sharma@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/amdgpu.h

@@ -1046,6 +1046,11 @@ struct amdgpu_device {
 	uint32_t                        *reset_dump_reg_list;
 	uint32_t			*reset_dump_reg_value;
 	int                             num_regs;
+#ifdef CONFIG_DEV_COREDUMP
+	struct amdgpu_task_info         reset_task_info;
+	bool                            reset_vram_lost;
+	struct timespec64               reset_time;
+#endif
 
 	bool                            scpm_enabled;
 	uint32_t                        scpm_status;

drivers/gpu/drm/amd/amdgpu/amdgpu_device.c

@@ -32,6 +32,8 @@
 #include <linux/slab.h>
 #include <linux/iommu.h>
 #include <linux/pci.h>
+#include <linux/devcoredump.h>
+#include <generated/utsrelease.h>
 
 #include <drm/drm_atomic_helper.h>
 #include <drm/drm_probe_helper.h>
@@ -4680,6 +4682,59 @@ static int amdgpu_reset_reg_dumps(struct amdgpu_device *adev)
 	return 0;
 }
 
+#ifdef CONFIG_DEV_COREDUMP
+static ssize_t amdgpu_devcoredump_read(char *buffer, loff_t offset,
+		size_t count, void *data, size_t datalen)
+{
+	struct drm_printer p;
+	struct amdgpu_device *adev = data;
+	struct drm_print_iterator iter;
+	int i;
+
+	iter.data = buffer;
+	iter.offset = 0;
+	iter.start = offset;
+	iter.remain = count;
+
+	p = drm_coredump_printer(&iter);
+
+	drm_printf(&p, "**** AMDGPU Device Coredump ****\n");
+	drm_printf(&p, "kernel: " UTS_RELEASE "\n");
+	drm_printf(&p, "module: " KBUILD_MODNAME "\n");
+	drm_printf(&p, "time: %lld.%09ld\n", adev->reset_time.tv_sec, adev->reset_time.tv_nsec);
+	if (adev->reset_task_info.pid)
+		drm_printf(&p, "process_name: %s PID: %d\n",
+			   adev->reset_task_info.process_name,
+			   adev->reset_task_info.pid);
+
+	if (adev->reset_vram_lost)
+		drm_printf(&p, "VRAM is lost due to GPU reset!\n");
+	if (adev->num_regs) {
+		drm_printf(&p, "AMDGPU register dumps:\nOffset:     Value:\n");
+
+		for (i = 0; i < adev->num_regs; i++)
+			drm_printf(&p, "0x%08x: 0x%08x\n",
+				   adev->reset_dump_reg_list[i],
+				   adev->reset_dump_reg_value[i]);
+	}
+
+	return count - iter.remain;
+}
+
+static void amdgpu_devcoredump_free(void *data)
+{
+}
+
+static void amdgpu_reset_capture_coredumpm(struct amdgpu_device *adev)
+{
+	struct drm_device *dev = adev_to_drm(adev);
+
+	ktime_get_ts64(&adev->reset_time);
+	dev_coredumpm(dev->dev, THIS_MODULE, adev, 0, GFP_KERNEL,
+		      amdgpu_devcoredump_read, amdgpu_devcoredump_free);
+}
+#endif
+
 int amdgpu_do_asic_reset(struct list_head *device_list_handle,
 			 struct amdgpu_reset_context *reset_context)
 {
@@ -4764,6 +4819,15 @@ int amdgpu_do_asic_reset(struct list_head *device_list_handle,
 					goto out;
 
 				vram_lost = amdgpu_device_check_vram_lost(tmp_adev);
+#ifdef CONFIG_DEV_COREDUMP
+				tmp_adev->reset_vram_lost = vram_lost;
+				memset(&tmp_adev->reset_task_info, 0,
+						sizeof(tmp_adev->reset_task_info));
+				if (reset_context->job && reset_context->job->vm)
+					tmp_adev->reset_task_info =
+						reset_context->job->vm->task_info;
+				amdgpu_reset_capture_coredumpm(tmp_adev);
+#endif
 				if (vram_lost) {
 					DRM_INFO("VRAM is lost due to GPU reset!\n");
 					amdgpu_inc_vram_lost(tmp_adev);