Commit 6cb31fba authored by René Rebe's avatar René Rebe Committed by Thomas Zimmermann
Browse files

drm/mgag200: Fix big-endian support 



Unlike the original, deleted Matrox mga driver, the new mgag200 driver
has the XRGB frame-buffer byte swapped on big-endian "RISC"
systems. Fix by enabling byte swapping "PowerPC" OPMODE for any
__BIG_ENDIAN config.

Fixes: 414c4531 ("mgag200: initial g200se driver (v2)")
Signed-off-by: default avatarRené Rebe <rene@exactco.de>
Cc: stable@kernel.org
Reviewed-by: default avatarThomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: default avatarThomas Zimmermann <tzimmermann@suse.de>
Link: https://patch.msgid.link/20251208.141827.965103015954471168.rene@exactco.de
parent a585c7ef

drivers/gpu/drm/mgag200/mgag200_mode.c

+25 −0
Original line number Diff line number Diff line
@@ -161,6 +161,30 @@ static void mgag200_set_startadd(struct mga_device *mdev, 
	WREG_ECRT(0x00, crtcext0);

}



/*

 * Set the opmode for the hardware swapper for Big-Endian processor

 * support for the frame buffer aperture and DMAWIN space.

 */

static void mgag200_set_datasiz(struct mga_device *mdev, u32 format)

{

#if defined(__BIG_ENDIAN)

	u32 opmode = RREG32(MGAREG_OPMODE);



	opmode &= ~(GENMASK(17, 16) | GENMASK(9, 8) | GENMASK(3, 2));



	/* Big-endian byte-swapping */

	switch (format) {

	case DRM_FORMAT_RGB565:

		opmode |= 0x10100;

		break;

	case DRM_FORMAT_XRGB8888:

		opmode |= 0x20200;

		break;

	}

	WREG32(MGAREG_OPMODE, opmode);

#endif

}



void mgag200_init_registers(struct mga_device *mdev)

{

	u8 crtc11, misc;
@@ -496,6 +520,7 @@ void mgag200_primary_plane_helper_atomic_update(struct drm_plane *plane, 
	struct drm_atomic_helper_damage_iter iter;

	struct drm_rect damage;



	mgag200_set_datasiz(mdev, fb->format->format);

	drm_atomic_helper_damage_iter_init(&iter, old_plane_state, plane_state);

	drm_atomic_for_each_plane_damage(&iter, &damage) {

		mgag200_handle_damage(mdev, shadow_plane_state->data, fb, &damage);