[PATCH v2] drm/amdgpu: add dce6 drm_panic support

[Jocelyn Falempe]

On 12/08/2024 08:09, Lu Yao wrote:
> Add support for the drm_panic module, which displays a pretty user
> friendly message on the screen when a Linux kernel panic occurs.

 From a drm_panic point of view, it looks good to me.
I don't have the required hardware, so unfortunately I wasn't able to 
test it.

Best regards,

-- 

Jocelyn


> 
> Signed-off-by: Lu Yao <yaolu at kylinos.cn>
> ---
> Changes in v2:
> 1. Drop include "drm_internal.h"
> 2. Add disabling DC tiling ops.
> Per suggestion from previous thread:
> https://patchwork.freedesktop.org/patch/606879/?series=136832&rev=1
> ---
>   drivers/gpu/drm/amd/amdgpu/dce_v6_0.c | 48 +++++++++++++++++++++++++++
>   1 file changed, 48 insertions(+)
> 
> diff --git a/drivers/gpu/drm/amd/amdgpu/dce_v6_0.c b/drivers/gpu/drm/amd/amdgpu/dce_v6_0.c
> index 05c0df97f01d..ba1b7a36caa3 100644
> --- a/drivers/gpu/drm/amd/amdgpu/dce_v6_0.c
> +++ b/drivers/gpu/drm/amd/amdgpu/dce_v6_0.c
> @@ -28,6 +28,7 @@
>   #include <drm/drm_modeset_helper.h>
>   #include <drm/drm_modeset_helper_vtables.h>
>   #include <drm/drm_vblank.h>
> +#include <drm/drm_panic.h>
>   
>   #include "amdgpu.h"
>   #include "amdgpu_pm.h"
> @@ -2600,6 +2601,52 @@ static const struct drm_crtc_helper_funcs dce_v6_0_crtc_helper_funcs = {
>   	.get_scanout_position = amdgpu_crtc_get_scanout_position,
>   };
>   
> +static int dce_v6_0_drm_primary_plane_get_scanout_buffer(struct drm_plane *plane,
> +							 struct drm_scanout_buffer *sb)
> +{
> +	struct drm_framebuffer *fb;
> +	struct amdgpu_bo *abo;
> +	struct amdgpu_crtc *amdgpu_crtc;
> +	struct amdgpu_device *adev;
> +	uint32_t fb_format;
> +
> +	if (!plane->fb)
> +		return -EINVAL;
> +
> +	fb = plane->fb;
> +
> +	abo = gem_to_amdgpu_bo(fb->obj[0]);
> +	amdgpu_crtc = to_amdgpu_crtc(plane->crtc);
> +	adev = drm_to_adev(fb->dev);
> +
> +	if (!abo->kmap.virtual &&
> +	    ttm_bo_kmap(&abo->tbo, 0, PFN_UP(abo->tbo.base.size), &abo->kmap)) {
> +		DRM_WARN("amdgpu bo map failed, panic won't be displayed\n");
> +		return -ENOMEM;
> +	}
> +
> +	if (abo->kmap.bo_kmap_type & TTM_BO_MAP_IOMEM_MASK)
> +		iosys_map_set_vaddr_iomem(&sb->map[0], abo->kmap.virtual);
> +	else
> +		iosys_map_set_vaddr(&sb->map[0], abo->kmap.virtual);
> +
> +	sb->width = fb->width;
> +	sb->height = fb->height;
> +	sb->format = fb->format;
> +	sb->pitch[0] = fb->pitches[0];
> +
> +	/* Disable DC tiling */
> +	fb_format = RREG32(mmGRPH_CONTROL + amdgpu_crtc->crtc_offset);
> +	fb_format &= ~GRPH_ARRAY_MODE(0x7);
> +	WREG32(mmGRPH_CONTROL + amdgpu_crtc->crtc_offset, fb_format);
> +
> +	return 0;
> +}
> +
> +static const struct drm_plane_helper_funcs dce_v6_0_drm_primary_plane_helper_funcs = {
> +	.get_scanout_buffer = dce_v6_0_drm_primary_plane_get_scanout_buffer
> +};
> +
>   static int dce_v6_0_crtc_init(struct amdgpu_device *adev, int index)
>   {
>   	struct amdgpu_crtc *amdgpu_crtc;
> @@ -2627,6 +2674,7 @@ static int dce_v6_0_crtc_init(struct amdgpu_device *adev, int index)
>   	amdgpu_crtc->encoder = NULL;
>   	amdgpu_crtc->connector = NULL;
>   	drm_crtc_helper_add(&amdgpu_crtc->base, &dce_v6_0_crtc_helper_funcs);
> +	drm_plane_helper_add(amdgpu_crtc->base.primary, &dce_v6_0_drm_primary_plane_helper_funcs);
>   
>   	return 0;
>   }