Re: [PATCH 2/2] drm: mali-dp: Check for sufficient address space

[Liviu Dudau]

On Mon, Jan 23, 2017 at 01:46:42PM +0000, Mihail Atanassov wrote:
> If the device-tree 'reg' node doesn't reserve enough
> space for the DP, fail to bind.
> 
> Reviewed-by: Brian Starkey <brian.starkey@xxxxxxx>
> Signed-off-by: Mihail Atanassov <mihail.atanassov@xxxxxxx>
> ---
>  drivers/gpu/drm/arm/malidp_drv.c  | 20 ++++++++++++++++++++
>  drivers/gpu/drm/arm/malidp_regs.h |  2 ++
>  2 files changed, 22 insertions(+)
> 
> diff --git a/drivers/gpu/drm/arm/malidp_drv.c b/drivers/gpu/drm/arm/malidp_drv.c
> index 43238f4..66622a5 100644
> --- a/drivers/gpu/drm/arm/malidp_drv.c
> +++ b/drivers/gpu/drm/arm/malidp_drv.c
> @@ -296,6 +296,20 @@ static bool malidp_is_compatible_hw_id(struct malidp_hw_device *hwdev,
>  	return true;
>  }
>  
> +static bool malidp_is_sufficient_address_space(const struct resource *res,
> +					       const struct of_device_id *dev_id)
> +{
> +	resource_size_t res_size = resource_size(res);
> +	const char *compatstr_dp500 = "arm,mali-dp500";
> +
> +	if (!strnstr(dev_id->compatible, compatstr_dp500,
> +		     sizeof(dev_id->compatible)))
> +		return res_size >= MALIDP550_ADDR_SPACE_SIZE;
> +	else if (res_size < MALIDP500_ADDR_SPACE_SIZE)
> +		return false;
> +	return true;
> +}
> +
>  #define MAX_OUTPUT_CHANNELS	3
>  
>  static int malidp_bind(struct device *dev)
> @@ -376,6 +390,12 @@ static int malidp_bind(struct device *dev)
>  		goto query_hw_fail;
>  	}
>  
> +	if (!malidp_is_sufficient_address_space(res, dev_id)) {
> +		DRM_ERROR("Insufficient address space in device-tree.\n");
> +		ret = -EINVAL;
> +		goto query_hw_fail;
> +	}
> +

Small nitpick: s/malidp_is_sufficient_address_space/malidp_has_sufficient_address_space/g

Otherwise, for the whole series:

Acked-by: Liviu Dudau <Liviu.Dudau@xxxxxxx>


>  	if (!malidp_is_compatible_hw_id(hwdev, dev_id)) {
>  		ret = -EINVAL;
>  		goto query_hw_fail;
> diff --git a/drivers/gpu/drm/arm/malidp_regs.h b/drivers/gpu/drm/arm/malidp_regs.h
> index 7a89997..e0651d2 100644
> --- a/drivers/gpu/drm/arm/malidp_regs.h
> +++ b/drivers/gpu/drm/arm/malidp_regs.h
> @@ -95,6 +95,7 @@
>  #define MALIDP_PRODUCT_ID(__core_id) ((u32)(__core_id) >> 16)
>  
>  /* register offsets and bits specific to DP500 */
> +#define MALIDP500_ADDR_SPACE_SIZE	0x01000
>  #define MALIDP500_DC_BASE		0x00000
>  #define MALIDP500_DC_CONTROL		0x0000c
>  #define   MALIDP500_DC_CONFIG_REQ	(1 << 17)
> @@ -127,6 +128,7 @@
>  #define MALIDP500_CONFIG_ID		0x00fd4
>  
>  /* register offsets and bits specific to DP550/DP650 */
> +#define MALIDP550_ADDR_SPACE_SIZE	0x10000
>  #define MALIDP550_DE_CONTROL		0x00010
>  #define MALIDP550_DE_LINE_COUNTER	0x00014
>  #define MALIDP550_DE_AXI_CONTROL	0x00018
> -- 
> 1.8.3
>