[PATCH v2 1/2] drm/amdgpu: add debugfs for reset registers list

[Christian König]

Am 11.02.22 um 12:47 schrieb Somalapuram Amaranath:
> List of register to be 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 | 61 +++++++++++++++++++++
>   2 files changed, 66 insertions(+)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
> index b85b67a88a3d..b90349b86918 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
> @@ -813,6 +813,7 @@ struct amd_powerplay {
>   
>   #define AMDGPU_RESET_MAGIC_NUM 64
>   #define AMDGPU_MAX_DF_PERFMONS 4
> +#define AMDGPU_RESET_DUMP_REGS_MAX     128
>   struct amdgpu_device {
>   	struct device			*dev;
>   	struct pci_dev			*pdev;
> @@ -1097,6 +1098,10 @@ 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[AMDGPU_RESET_DUMP_REGS_MAX];

Using an xarray or just dynamic allocation with krealloc_array would 
probably be better.

Regards,
Christian.

> +	int				n_regs;
>   };
>   
>   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..fb99f3d657a4 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c
> @@ -1609,6 +1609,65 @@ 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;
> +	int i, r, len;
> +
> +	reg_offset = kmalloc(2048, GFP_KERNEL);
> +	memset(reg_offset,  0, 2048);
> +	for (i = 0; i < adev->n_regs; i++)
> +		sprintf(reg_offset + strlen(reg_offset), "0x%x ", adev->reset_dump_reg_list[i]);
> +
> +	sprintf(reg_offset + strlen(reg_offset), "\n");
> +	len = strlen(reg_offset);
> +
> +	if (*pos >=  len)
> +		return 0;
> +
> +	r = copy_to_user(buf, reg_offset, len);
> +	*pos += len - r;
> +	kfree(reg_offset);
> +
> +	return len - r;
> +}
> +
> +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;
> +	int ret, i = 0;
> +
> +	reg_offset = kmalloc(size, GFP_KERNEL);
> +	memset(reg_offset,  0, size);
> +	ret = copy_from_user(reg_offset, buf, size);
> +
> +	if (ret)
> +		return -EFAULT;
> +
> +	while ((reg = strsep(&reg_offset, " ")) != NULL) {
> +		ret  = kstrtouint(reg, 16, &adev->reset_dump_reg_list[i]);
> +		if (ret)
> +			return -EINVAL;
> +		i++;
> +	}
> +
> +	adev->n_regs = i;
> +	kfree(reg_offset);
> +
> +	return size;
> +}
> +
> +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;
> @@ -1672,6 +1731,8 @@ 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;