On Tue, Apr 01, 2025 at 02:51:08PM +0200, Jocelyn Falempe wrote:
> drm_panic draws in linear framebuffer, so it's easier to re-use the
> current framebuffer, and disable tiling in the panic handler, to show
> the panic screen.
>
> Signed-off-by: Jocelyn Falempe <jfale...@redhat.com>
> ---
> drivers/gpu/drm/i915/display/i9xx_plane.c | 23 +++++++++++++++++++
> .../drm/i915/display/intel_display_types.h | 2 ++
> 2 files changed, 25 insertions(+)
>
> diff --git a/drivers/gpu/drm/i915/display/i9xx_plane.c
> b/drivers/gpu/drm/i915/display/i9xx_plane.c
> index 5e8344fdfc28..9c93d5ac7129 100644
> --- a/drivers/gpu/drm/i915/display/i9xx_plane.c
> +++ b/drivers/gpu/drm/i915/display/i9xx_plane.c
> @@ -908,6 +908,27 @@ static const struct drm_plane_funcs i8xx_plane_funcs = {
> .format_mod_supported = i8xx_plane_format_mod_supported,
> };
>
> +static void i9xx_disable_tiling(struct intel_plane *plane)
> +{
> + struct intel_display *display = to_intel_display(plane);
> + enum i9xx_plane_id i9xx_plane = plane->i9xx_plane;
> + u32 dspcntr;
> + u32 reg;
> +
> + dspcntr = intel_de_read_fw(display, DSPCNTR(display, i9xx_plane));
> + dspcntr &= ~DISP_TILED;
> + intel_de_write_fw(display, DSPCNTR(display, i9xx_plane), dspcntr);
This fails to account all the different alignment/etc. restrictions
between linear vs. tiled. I don't think we want hacks like this.
> +
> + if (DISPLAY_VER(display) >= 4) {
> + reg = intel_de_read_fw(display, DSPSURF(display, i9xx_plane));
> + intel_de_write_fw(display, DSPSURF(display, i9xx_plane), reg);
> +
> + } else {
> + reg = intel_de_read_fw(display, DSPADDR(display, i9xx_plane));
> + intel_de_write_fw(display, DSPADDR(display, i9xx_plane), reg);
> + }
> +}
> +
> struct intel_plane *
> intel_primary_plane_create(struct intel_display *display, enum pipe pipe)
> {
> @@ -1050,6 +1071,8 @@ intel_primary_plane_create(struct intel_display
> *display, enum pipe pipe)
> }
> }
>
> + plane->disable_tiling = i9xx_disable_tiling;
> +
> modifiers = intel_fb_plane_get_modifiers(display,
> INTEL_PLANE_CAP_TILING_X);
>
> if (DISPLAY_VER(display) >= 5 || display->platform.g4x)
> diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h
> b/drivers/gpu/drm/i915/display/intel_display_types.h
> index 367b53a9eae2..62d0785c9edf 100644
> --- a/drivers/gpu/drm/i915/display/intel_display_types.h
> +++ b/drivers/gpu/drm/i915/display/intel_display_types.h
> @@ -1512,6 +1512,8 @@ struct intel_plane {
> bool async_flip);
> void (*enable_flip_done)(struct intel_plane *plane);
> void (*disable_flip_done)(struct intel_plane *plane);
> + /* For drm_panic */
> + void (*disable_tiling)(struct intel_plane *plane);
> };
>
> #define to_intel_atomic_state(x) container_of(x, struct intel_atomic_state,
> base)
> --
> 2.49.0
--
Ville Syrjälä
Intel
