[PATCH] Only align screen / scanout pixmap height where necessary

[Michel Dänzer]

From: Michel Dänzer <michel.daenzer at amd.com>

When using glamor acceleration, the pixmap's header has to have a height
that matches exactly what the actual height is minus the GPU memory
alignment. Otherwise CRTCs scanning out from the main scanout buffer
(e.g. every CRTC that isn't rotated or transformed in some way) won't
always work. This results in a bug where rotating one monitor in a
multi-monitor setup won't always work properly. Easiest way to reproduce
this:

- Have two monitors (I've gotten this working with a 1920x1080 and
  1280x1024, along with two 1920x1080s)
- Rotate one of them from 0° to 90°, then rotate the same monitor from
  90° to 180°. The monitor that hasn't been rotated won't properly
  update, and will stay on a blank screen

This doesn't seem to make any difference when using EXA for
acceleration.

Compared to Stephen Chandler's patch, this drops the height alignment
in most places and only keeps it where it's really necessary.

Reported-by: Stephen Chandler Paul <cpaul at redhat.com>
Signed-off-by: Michel Dänzer <michel.daenzer at amd.com>
---

Stephen Chandler,

thanks for the good catch, but I think we can take this even further.
Does this fix the problem for you as well?

 src/drmmode_display.c | 18 ++++++++----------
 1 file changed, 8 insertions(+), 10 deletions(-)

diff --git a/src/drmmode_display.c b/src/drmmode_display.c
index efc35f0..623124e 100644
--- a/src/drmmode_display.c
+++ b/src/drmmode_display.c
@@ -525,6 +525,7 @@ drmmode_crtc_scanout_allocate(xf86CrtcPtr crtc,
 	RADEONInfoPtr info = RADEONPTR(pScrn);
 	drmmode_crtc_private_ptr drmmode_crtc = crtc->driver_private;
 	drmmode_ptr drmmode = drmmode_crtc->drmmode;
+	int aligned_height;
 	int size;
 	int ret;
 	unsigned long rotate_pitch;
@@ -547,9 +548,9 @@ drmmode_crtc_scanout_allocate(xf86CrtcPtr crtc,
 	rotate_pitch =
 		RADEON_ALIGN(width, drmmode_get_pitch_align(pScrn, drmmode->cpp, 0))
 		* drmmode->cpp;
-	height = RADEON_ALIGN(height, drmmode_get_height_align(pScrn, 0));
+	aligned_height = RADEON_ALIGN(height, drmmode_get_height_align(pScrn, 0));
 	base_align = drmmode_get_base_align(pScrn, drmmode->cpp, 0);
-	size = RADEON_ALIGN(rotate_pitch * height, RADEON_GPU_PAGE_SIZE);
+	size = RADEON_ALIGN(rotate_pitch * aligned_height, RADEON_GPU_PAGE_SIZE);
 
 	scanout->bo = radeon_bo_open(drmmode->bufmgr, 0, size, base_align,
 				     RADEON_GEM_DOMAIN_VRAM, 0);
@@ -633,7 +634,6 @@ drmmode_set_mode_major(xf86CrtcPtr crtc, DisplayModePtr mode,
 	drmModeModeInfo kmode;
 	int pitch;
 	uint32_t tiling_flags = 0;
-	int height;
 
 	if (info->allowColorTiling) {
 		if (info->ChipFamily >= CHIP_FAMILY_R600)
@@ -644,14 +644,13 @@ drmmode_set_mode_major(xf86CrtcPtr crtc, DisplayModePtr mode,
 
 	pitch = RADEON_ALIGN(pScrn->displayWidth, drmmode_get_pitch_align(pScrn, info->pixel_bytes, tiling_flags)) *
 		info->pixel_bytes;
-	height = RADEON_ALIGN(pScrn->virtualY, drmmode_get_height_align(pScrn, tiling_flags));
 	if (info->ChipFamily >= CHIP_FAMILY_R600) {
 		pitch = info->front_surface.level[0].pitch_bytes;
 	}
 
 	if (drmmode->fb_id == 0) {
 		ret = drmModeAddFB(drmmode->fd,
-				   pScrn->virtualX, height,
+				   pScrn->virtualX, pScrn->virtualY,
                                    pScrn->depth, pScrn->bitsPerPixel,
 				   pitch,
 				   info->front_bo->handle,
@@ -1789,6 +1788,7 @@ drmmode_xf86crtc_resize (ScrnInfoPtr scrn, int width, int height)
 	ScreenPtr   screen = xf86ScrnToScreen(scrn);
 	uint32_t    old_fb_id;
 	int	    i, pitch, old_width, old_height, old_pitch;
+	int aligned_height;
 	uint32_t screen_size;
 	int cpp = info->pixel_bytes;
 	struct radeon_bo *front_bo;
@@ -1822,8 +1822,8 @@ drmmode_xf86crtc_resize (ScrnInfoPtr scrn, int width, int height)
 	}
 
 	pitch = RADEON_ALIGN(width, drmmode_get_pitch_align(scrn, cpp, tiling_flags)) * cpp;
-	height = RADEON_ALIGN(height, drmmode_get_height_align(scrn, tiling_flags));
-	screen_size = RADEON_ALIGN(pitch * height, RADEON_GPU_PAGE_SIZE);
+	aligned_height = RADEON_ALIGN(height, drmmode_get_height_align(scrn, tiling_flags));
+	screen_size = RADEON_ALIGN(pitch * aligned_height, RADEON_GPU_PAGE_SIZE);
 	base_align = 4096;
 	if (info->ChipFamily >= CHIP_FAMILY_R600) {
 		memset(&surface, 0, sizeof(struct radeon_surface));
@@ -2473,7 +2473,6 @@ Bool radeon_do_pageflip(ScrnInfoPtr scrn, ClientPtr client,
 	unsigned int pitch;
 	int i;
 	uint32_t tiling_flags = 0;
-	int height;
 	drmmode_flipdata_ptr flipdata;
 	drmmode_flipevtcarrier_ptr flipcarrier = NULL;
 	struct radeon_drm_queue_entry *drm_queue = NULL;
@@ -2487,7 +2486,6 @@ Bool radeon_do_pageflip(ScrnInfoPtr scrn, ClientPtr client,
 
 	pitch = RADEON_ALIGN(scrn->displayWidth, drmmode_get_pitch_align(scrn, info->pixel_bytes, tiling_flags)) *
 		info->pixel_bytes;
-	height = RADEON_ALIGN(scrn->virtualY, drmmode_get_height_align(scrn, tiling_flags));
 	if (info->ChipFamily >= CHIP_FAMILY_R600 && info->surf_man) {
 		pitch = info->front_surface.level[0].pitch_bytes;
 	}
@@ -2503,7 +2501,7 @@ Bool radeon_do_pageflip(ScrnInfoPtr scrn, ClientPtr client,
 	 * Create a new handle for the back buffer
 	 */
 	flipdata->old_fb_id = drmmode->fb_id;
-	if (drmModeAddFB(drmmode->fd, scrn->virtualX, height,
+	if (drmModeAddFB(drmmode->fd, scrn->virtualX, scrn->virtualY,
 			 scrn->depth, scrn->bitsPerPixel, pitch,
 			 new_front_handle, &drmmode->fb_id))
 		goto error;
-- 
2.6.0