Re: [PATCH v7 2/6] drm/panthor: Simplify getting the GPU model name

[Steven Price <steven.price@arm.com>]

On 24/07/2025 10:25, Karunika Choo wrote:
> This patch replaces the panthor_model structure with a simple switch
> case based on the product_id which is in the format of:
>         ((arch_major << 24) | product_major)
> 
> This simplifies comparison and allows extending of the function to
> accommodate naming differences based on supported GPU features.
> 
> Reviewed-by: Chia-I Wu <olvaffe@gmail.com>
> Reviewed-by: Liviu Dudau <liviu.dudau@arm.com>
> Signed-off-by: Karunika Choo <karunika.choo@arm.com>

Reviewed-by: Steven Price <steven.price@arm.com>

> ---
>  drivers/gpu/drm/panthor/panthor_hw.c | 61 ++++++++--------------------
>  1 file changed, 17 insertions(+), 44 deletions(-)
> 
> diff --git a/drivers/gpu/drm/panthor/panthor_hw.c b/drivers/gpu/drm/panthor/panthor_hw.c
> index 3f7175cb0ab4..f39010c0ca86 100644
> --- a/drivers/gpu/drm/panthor/panthor_hw.c
> +++ b/drivers/gpu/drm/panthor/panthor_hw.c
> @@ -5,39 +5,22 @@
>  #include "panthor_hw.h"
>  #include "panthor_regs.h"
>  
> -/**
> - * struct panthor_model - GPU model description
> - */
> -struct panthor_model {
> -	/** @name: Model name. */
> -	const char *name;
> -
> -	/** @arch_major: Major version number of architecture. */
> -	u8 arch_major;
> -
> -	/** @product_major: Major version number of product. */
> -	u8 product_major;
> -};
> -
> -/**
> - * GPU_MODEL() - Define a GPU model. A GPU product can be uniquely identified
> - * by a combination of the major architecture version and the major product
> - * version.
> - * @_name: Name for the GPU model.
> - * @_arch_major: Architecture major.
> - * @_product_major: Product major.
> - */
> -#define GPU_MODEL(_name, _arch_major, _product_major) \
> -{\
> -	.name = __stringify(_name),				\
> -	.arch_major = _arch_major,				\
> -	.product_major = _product_major,			\
> -}
> +#define GPU_PROD_ID_MAKE(arch_major, prod_major) \
> +	(((arch_major) << 24) | (prod_major))
> +
> +static char *get_gpu_model_name(struct panthor_device *ptdev)
> +{
> +	const u32 gpu_id = ptdev->gpu_info.gpu_id;
> +	const u32 product_id = GPU_PROD_ID_MAKE(GPU_ARCH_MAJOR(gpu_id),
> +						GPU_PROD_MAJOR(gpu_id));
> +
> +	switch (product_id) {
> +	case GPU_PROD_ID_MAKE(10, 7):
> +		return "Mali-G610";
> +	}
>  
> -static const struct panthor_model gpu_models[] = {
> -	GPU_MODEL(g610, 10, 7),
> -	{},
> -};
> +	return "(Unknown Mali GPU)";
> +}
>  
>  static void panthor_gpu_info_init(struct panthor_device *ptdev)
>  {
> @@ -68,27 +51,17 @@ static void panthor_gpu_info_init(struct panthor_device *ptdev)
>  
>  static void panthor_hw_info_init(struct panthor_device *ptdev)
>  {
> -	const struct panthor_model *model;
> -	u32 arch_major, product_major;
>  	u32 major, minor, status;
>  
>  	panthor_gpu_info_init(ptdev);
>  
> -	arch_major = GPU_ARCH_MAJOR(ptdev->gpu_info.gpu_id);
> -	product_major = GPU_PROD_MAJOR(ptdev->gpu_info.gpu_id);
>  	major = GPU_VER_MAJOR(ptdev->gpu_info.gpu_id);
>  	minor = GPU_VER_MINOR(ptdev->gpu_info.gpu_id);
>  	status = GPU_VER_STATUS(ptdev->gpu_info.gpu_id);
>  
> -	for (model = gpu_models; model->name; model++) {
> -		if (model->arch_major == arch_major &&
> -		    model->product_major == product_major)
> -			break;
> -	}
> -
>  	drm_info(&ptdev->base,
> -		 "mali-%s id 0x%x major 0x%x minor 0x%x status 0x%x",
> -		 model->name ?: "unknown", ptdev->gpu_info.gpu_id >> 16,
> +		 "%s id 0x%x major 0x%x minor 0x%x status 0x%x",
> +		 get_gpu_model_name(ptdev), ptdev->gpu_info.gpu_id >> 16,
>  		 major, minor, status);
>  
>  	drm_info(&ptdev->base,