[PATCH 2/2] drm/amdgpu: add AMDGPURESET uevent on AMD GPU reset

[Somalapuram Amaranath <Amaranath.Somalapuram@amd.com>]

AMDGPURESET uevent added to notify userspace, collect dump_stack and trace

Signed-off-by: Somalapuram Amaranath <Amaranath.Somalapuram@amd.com>
---
 drivers/gpu/drm/amd/amdgpu/nv.c | 45 +++++++++++++++++++++++++++++++++
 1 file changed, 45 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/nv.c b/drivers/gpu/drm/amd/amdgpu/nv.c
index 2ec1ffb36b1f..b73147ae41fb 100644
--- a/drivers/gpu/drm/amd/amdgpu/nv.c
+++ b/drivers/gpu/drm/amd/amdgpu/nv.c
@@ -529,10 +529,55 @@ nv_asic_reset_method(struct amdgpu_device *adev)
 	}
 }
 
+/**
+ * drm_sysfs_reset_event - generate a DRM uevent
+ * @dev: DRM device
+ *
+ * Send a uevent for the DRM device specified by @dev.  Currently we only
+ * set AMDGPURESET=1 in the uevent environment, but this could be expanded to
+ * deal with other types of events.
+ *
+ * Any new uapi should be using the drm_sysfs_connector_status_event()
+ * for uevents on connector status change.
+ */
+void drm_sysfs_reset_event(struct drm_device *dev)
+{
+	char *event_string = "AMDGPURESET=1";
+	char *envp[2] = { event_string, NULL };
+
+	kobject_uevent_env(&dev->primary->kdev->kobj, KOBJ_CHANGE, envp);
+}
+
+void amdgpu_reset_dumps(struct amdgpu_device *adev)
+{
+	struct drm_device *ddev = adev_to_drm(adev);
+	int r = 0, i;
+
+	/* original raven doesn't have full asic reset */
+	if ((adev->apu_flags & AMD_APU_IS_RAVEN) &&
+		!(adev->apu_flags & AMD_APU_IS_RAVEN2))
+		return;
+	for (i = 0; i < adev->num_ip_blocks; i++) {
+		if (!adev->ip_blocks[i].status.valid)
+			continue;
+		if (!adev->ip_blocks[i].version->funcs->reset_reg_dumps)
+			continue;
+		r = adev->ip_blocks[i].version->funcs->reset_reg_dumps(adev);
+
+		if (r)
+			DRM_ERROR("reset_reg_dumps of IP block <%s> failed %d\n",
+					adev->ip_blocks[i].version->funcs->name, r);
+	}
+
+	drm_sysfs_reset_event(ddev);
+	dump_stack();
+}
+
 static int nv_asic_reset(struct amdgpu_device *adev)
 {
 	int ret = 0;
 
+	amdgpu_reset_dumps(adev);
 	switch (nv_asic_reset_method(adev)) {
 	case AMD_RESET_METHOD_PCI:
 		dev_info(adev->dev, "PCI reset\n");
-- 
2.25.1