[PATCH 2/8] drm/amdgpu: add a generic fb accessing helper function

[Christian König]

Am 08.10.19 um 21:29 schrieb Alex Deucher:
> From: "Tianci.Yin" <tianci.yin at amd.com>
>
> add a generic helper function for accessing framebuffer via MMIO
>
> Change-Id: I4baa0aa53c93a94c2eff98c6211a61f369239982
> Reviewed-by: Alex Deucher <alexander.deucher at amd.com>
> Signed-off-by: Tianci.Yin <tianci.yin at amd.com>
> ---
>   drivers/gpu/drm/amd/amdgpu/amdgpu.h           |  2 +
>   drivers/gpu/drm/amd/amdgpu/amdgpu_device.c    | 42 +++++++++++++++++++
>   drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c | 13 +-----
>   3 files changed, 45 insertions(+), 12 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
> index 17ccb9015141..0d60c2e6c592 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
> @@ -985,6 +985,8 @@ int amdgpu_device_init(struct amdgpu_device *adev,
>   void amdgpu_device_fini(struct amdgpu_device *adev);
>   int amdgpu_gpu_wait_for_idle(struct amdgpu_device *adev);
>   
> +int amdgpu_device_vram_access(struct amdgpu_device *adev, loff_t pos,
> +		       uint32_t *buf, size_t size, bool write);
>   uint32_t amdgpu_mm_rreg(struct amdgpu_device *adev, uint32_t reg,
>   			uint32_t acc_flags);
>   void amdgpu_mm_wreg(struct amdgpu_device *adev, uint32_t reg, uint32_t v,
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> index f25275abf408..53ce227f759c 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> @@ -153,6 +153,48 @@ bool amdgpu_device_is_px(struct drm_device *dev)
>   	return false;
>   }
>   
> +/**
> + * VRAM access helper functions.
> + *
> + * amdgpu_device_vram_access - read/write a buffer in vram
> + *
> + * @adev: amdgpu_device pointer
> + * @pos: offset of the buffer in vram
> + * @buf: virtual address of the buffer in system memory
> + * @size: read/write size, sizeof(@buf) must > @size
> + * @write: true - write to vram, otherwise - read from vram
> + *
> + * Returns 0 on success or an -error on failure.
> + */
> +int amdgpu_device_vram_access(struct amdgpu_device *adev, loff_t pos,
> +		       uint32_t *buf, size_t size, bool write)

Indentation seems to be incorrect here.

> +{
> +	uint64_t end = pos + size;
> +	unsigned long flags;
> +
> +	if (IS_ERR_OR_NULL(buf) ||
> +	    (adev->gmc.mc_vram_size > 0 &&
> +	     end > adev->gmc.mc_vram_size)) {
> +		DRM_ERROR("parameter error! pos:%llx, buf:%llx, size:%zx.\n",
> +			  pos, (u64)buf, size);
> +		return -EINVAL;
> +	}

Please drop that, this is a purely internal functions and parameter 
checking like this doesn't really make sense.

Regards,
Christian.

> +
> +	while (pos < end) {
> +		spin_lock_irqsave(&adev->mmio_idx_lock, flags);
> +		WREG32_NO_KIQ(mmMM_INDEX, ((uint32_t)pos) | 0x80000000);
> +		WREG32_NO_KIQ(mmMM_INDEX_HI, pos >> 31);
> +		if (write)
> +			WREG32_NO_KIQ(mmMM_DATA, *buf++);
> +		else
> +			*buf++ = RREG32_NO_KIQ(mmMM_DATA);
> +		spin_unlock_irqrestore(&adev->mmio_idx_lock, flags);
> +		pos += 4;
> +	}
> +
> +	return 0;
> +}
> +
>   /*
>    * MMIO register access helper functions.
>    */
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c
> index db2dab3a6dff..324c2d605f54 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c
> @@ -134,21 +134,10 @@ static int hw_id_map[MAX_HWIP] = {
>   
>   static int amdgpu_discovery_read_binary(struct amdgpu_device *adev, uint8_t *binary)
>   {
> -	uint32_t *p = (uint32_t *)binary;
>   	uint64_t vram_size = (uint64_t)RREG32(mmRCC_CONFIG_MEMSIZE) << 20;
>   	uint64_t pos = vram_size - BINARY_MAX_SIZE;
> -	unsigned long flags;
> -
> -	while (pos < vram_size) {
> -		spin_lock_irqsave(&adev->mmio_idx_lock, flags);
> -		WREG32_NO_KIQ(mmMM_INDEX, ((uint32_t)pos) | 0x80000000);
> -		WREG32_NO_KIQ(mmMM_INDEX_HI, pos >> 31);
> -		*p++ = RREG32_NO_KIQ(mmMM_DATA);
> -		spin_unlock_irqrestore(&adev->mmio_idx_lock, flags);
> -		pos += 4;
> -	}
>   
> -	return 0;
> +	return amdgpu_device_vram_access(adev, pos, (uint32_t *)binary, BINARY_MAX_SIZE, false);
>   }
>   
>   static uint16_t amdgpu_discovery_calculate_checksum(uint8_t *data, uint32_t size)