[PATCH v6 1/2] drm/amdgpu: add debugfs for reset registers list

[Somalapuram Amaranath]

List of register populated for dump collection during the GPU reset.

Signed-off-by: Somalapuram Amaranath <Amaranath.Somalapuram at amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu.h         |  5 ++
 drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c | 95 +++++++++++++++++++++
 2 files changed, 100 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
index b85b67a88a3d..57965316873b 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
@@ -1097,6 +1097,11 @@ struct amdgpu_device {
 
 	struct amdgpu_reset_control     *reset_cntl;
 	uint32_t                        ip_versions[HW_ID_MAX][HWIP_MAX_INSTANCE];
+
+	/* reset dump register */
+	uint32_t			*reset_dump_reg_list;
+	int                             n_regs;
+	struct mutex			reset_dump_mutex;
 };
 
 static inline struct amdgpu_device *drm_to_adev(struct drm_device *ddev)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c
index 164d6a9e9fbb..faf985c7cb93 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c
@@ -1609,6 +1609,98 @@ DEFINE_DEBUGFS_ATTRIBUTE(fops_ib_preempt, NULL,
 DEFINE_DEBUGFS_ATTRIBUTE(fops_sclk_set, NULL,
 			amdgpu_debugfs_sclk_set, "%llu\n");
 
+static ssize_t amdgpu_reset_dump_register_list_read(struct file *f,
+				char __user *buf, size_t size, loff_t *pos)
+{
+	struct amdgpu_device *adev = (struct amdgpu_device *)file_inode(f)->i_private;
+	char reg_offset[11];
+	int i, r, len = 0;
+
+	if (*pos)
+		return 0;
+
+	if (adev->n_regs == 0)
+		return 0;
+
+	for (i = 0; i < adev->n_regs; i++) {
+		sprintf(reg_offset, "0x%x ", adev->reset_dump_reg_list[i]);
+		r = copy_to_user(buf + len, reg_offset, strlen(reg_offset));
+
+		if (r)
+			return -EFAULT;
+
+		len += strlen(reg_offset);
+	}
+
+	r = copy_to_user(buf + len, "\n", 1);
+
+	if (r)
+		return -EFAULT;
+
+	len++;
+	*pos += len;
+
+	return len;
+}
+
+static ssize_t amdgpu_reset_dump_register_list_write(struct file *f,
+			const char __user *buf, size_t size, loff_t *pos)
+{
+	struct amdgpu_device *adev = (struct amdgpu_device *)file_inode(f)->i_private;
+	char *reg_offset, *reg, reg_temp[11];
+	static int alloc_count;
+	int ret, i = 0, len = 0;
+
+	do {
+		reg_offset = reg_temp;
+		memset(reg_offset,  0, 11);
+		ret = copy_from_user(reg_offset, buf + len, min(11, ((int)size-len)));
+
+		if (ret)
+			goto failed;
+
+		reg = strsep(&reg_offset, " ");
+
+		if (alloc_count <= i) {
+			adev->reset_dump_reg_list =  krealloc_array(
+							adev->reset_dump_reg_list, 1,
+							sizeof(uint32_t), GFP_KERNEL);
+			alloc_count++;
+		}
+
+		ret = kstrtouint(reg, 16, &adev->reset_dump_reg_list[i]);
+
+		if (ret)
+			goto failed;
+
+		len += strlen(reg) + 1;
+		i++;
+
+	} while (len < size);
+
+	adev->n_regs = i;
+
+	return size;
+
+failed:
+	mutex_lock(&adev->reset_dump_mutex);
+	kfree(adev->reset_dump_reg_list);
+	adev->reset_dump_reg_list = NULL;
+	alloc_count = 0;
+	adev->n_regs = 0;
+	mutex_unlock(&adev->reset_dump_mutex);
+	return -EFAULT;
+}
+
+
+
+static const struct file_operations amdgpu_reset_dump_register_list = {
+	.owner = THIS_MODULE,
+	.read = amdgpu_reset_dump_register_list_read,
+	.write = amdgpu_reset_dump_register_list_write,
+	.llseek = default_llseek
+};
+
 int amdgpu_debugfs_init(struct amdgpu_device *adev)
 {
 	struct dentry *root = adev_to_drm(adev)->primary->debugfs_root;
@@ -1618,6 +1710,7 @@ int amdgpu_debugfs_init(struct amdgpu_device *adev)
 	if (!debugfs_initialized())
 		return 0;
 
+	mutex_init(&adev->reset_dump_mutex);
 	ent = debugfs_create_file("amdgpu_preempt_ib", 0600, root, adev,
 				  &fops_ib_preempt);
 	if (IS_ERR(ent)) {
@@ -1672,6 +1765,8 @@ int amdgpu_debugfs_init(struct amdgpu_device *adev)
 			    &amdgpu_debugfs_test_ib_fops);
 	debugfs_create_file("amdgpu_vm_info", 0444, root, adev,
 			    &amdgpu_debugfs_vm_info_fops);
+	debugfs_create_file("amdgpu_reset_dump_register_list", 0644, root, adev,
+			    &amdgpu_reset_dump_register_list);
 
 	adev->debugfs_vbios_blob.data = adev->bios;
 	adev->debugfs_vbios_blob.size = adev->bios_size;
-- 
2.25.1