Re: [PATCH v7 2/8] drm/panthor: Add register definitions for perf

[Liviu Dudau <liviu.dudau@arm.com>]

On Sun, Oct 11, 2026 at 06:36:49PM +0100, Lukas Zapolskas wrote:
> The perfcnt_size register, needed to size the FW-side ring buffer, is
> comprised out of two fields, FIRMWARE_SIZE and HARDWARE_SIZE, indicating
> the size of the corresponding components of a single sample. The total
> size of a single sample in that ring buffer is the sum of the two.
> 
> The perfcnt_config register configures the size of the ring buffer, the
> counter set requested by the user, and whether the optional metadata block
> is required.
> 
> For newer FW revisions, the perfcnt_features register reports the
> presence of an optional metadata block.
> 
> GPUs with arch major 11 or greater also report the number of performance
> counters in a single counter block via the GPU_PRFCNT_FEATURES.
> 
> Signed-off-by: Lukas Zapolskas <lukas.zapolskas@arm.com>

Reviewed-by: Liviu Dudau <liviu.dudau@arm.com>

Best regards,
Liviu

> ---
>  drivers/gpu/drm/panthor/panthor_fw.h       | 9 ++++++++-
>  drivers/gpu/drm/panthor/panthor_gpu_regs.h | 4 ++++
>  2 files changed, 12 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/panthor/panthor_fw.h b/drivers/gpu/drm/panthor/panthor_fw.h
> index a99a9b6f4825..124e2b40b15f 100644
> --- a/drivers/gpu/drm/panthor/panthor_fw.h
> +++ b/drivers/gpu/drm/panthor/panthor_fw.h
> @@ -198,8 +198,12 @@ struct panthor_fw_global_control_iface {
>  	u32 output_va;
>  	u32 group_num;
>  	u32 group_stride;
> +#define GLB_PERFCNT_FW_SIZE(x) ((((x) >> 16) << 8))
> +#define GLB_PERFCNT_HW_SIZE(x) (((x) & GENMASK(15, 0)) << 8)
>  	u32 perfcnt_size;
>  	u32 instr_features;
> +#define PERFCNT_FEATURES_MD_SIZE(x) (((x) & GENMASK(3, 0)) << 8)
> +	u32 perfcnt_features;
>  };
>  
>  struct panthor_fw_global_input_iface {
> @@ -208,7 +212,7 @@ struct panthor_fw_global_input_iface {
>  #define GLB_CFG_ALLOC_EN			BIT(2)
>  #define GLB_CFG_POWEROFF_TIMER			BIT(3)
>  #define GLB_PROTM_ENTER				BIT(4)
> -#define GLB_PERFCNT_EN				BIT(5)
> +#define GLB_PERFCNT_ENABLE			BIT(5)
>  #define GLB_PERFCNT_SAMPLE			BIT(6)
>  #define GLB_COUNTER_EN				BIT(7)
>  #define GLB_PING				BIT(8)
> @@ -248,6 +252,9 @@ struct panthor_fw_global_input_iface {
>  	u64 perfcnt_base;
>  	u32 perfcnt_extract;
>  	u32 reserved3[3];
> +#define GLB_PERFCNT_CONFIG_SIZE(x) ((x) & GENMASK(7, 0))
> +#define GLB_PERFCNT_CONFIG_SET(x) (((x) & GENMASK(1, 0)) << 8)
> +#define GLB_PERFCNT_METADATA_ENABLE BIT(10)
>  	u32 perfcnt_config;
>  	u32 perfcnt_csg_select;
>  	u32 perfcnt_fw_enable;
> diff --git a/drivers/gpu/drm/panthor/panthor_gpu_regs.h b/drivers/gpu/drm/panthor/panthor_gpu_regs.h
> index 4c5b953796e4..2f0877068e44 100644
> --- a/drivers/gpu/drm/panthor/panthor_gpu_regs.h
> +++ b/drivers/gpu/drm/panthor/panthor_gpu_regs.h
> @@ -23,6 +23,7 @@
>  #define GPU_TILER_FEATURES				0xC
>  #define GPU_MEM_FEATURES				0x10
>  #define   GROUPS_L2_COHERENT				BIT(0)
> +#define   GPU_MEM_FEATURES_L2_SLICES(x)			((((x) & GENMASK(11, 8)) >> 8) + 1)
>  
>  #define GPU_MMU_FEATURES				0x14
>  #define  GPU_MMU_FEATURES_VA_BITS(x)			((x) & GENMASK(7, 0))
> @@ -69,6 +70,9 @@
>  #define   GPU_FEATURES_RAY_INTERSECTION			BIT(2)
>  #define   GPU_FEATURES_RAY_TRAVERSAL			BIT(5)
>  
> +#define GPU_PRFCNT_FEATURES				0x68
> +#define   PRFCNT_FEATURES_COUNTER_BLOCK_SIZE(x)		(((x) & GENMASK(7, 0)) << 8)
> +
>  #define GPU_TIMESTAMP_OFFSET				0x88
>  #define GPU_CYCLE_COUNT					0x90
>  #define GPU_TIMESTAMP					0x98
> 
> -- 
> 2.43.0
> 

-- 
====================
| I would like to |
| fix the world,  |
| but they're not |
| giving me the   |
 \ source code!  /
  ---------------
    ¯\_(ツ)_/¯