drm/tilcdc: Adjust the FB_CEILING address

The LCDC seems to expect its framebuffer ceiling address pointer to be
an inclusive bound.  The IP rev2 seems to cope with that but rev1 (as
found on the LCDK) don't.
Also note that this is what the framebuffer code does in da8xx-fb.c.

Since, as the TRM puts it, "The 2 LSBs are hardwired to 00b", the
dma_addr_t can be decremented without cast.
I tested it with a v2 (AM335x, rev  0x4F201000) and an LCDK (v1).

Signed-off-by: Karl Beldan <kbeldan@baylibre.com>
Signed-off-by: Jyri Sarha <jsarha@ti.com>
This commit is contained in:
Karl Beldan 2016-08-23 12:56:59 +00:00 committed by Jyri Sarha
parent a3479c4fa0
commit ee8c42baeb

View file

@ -80,7 +80,7 @@ static void set_scanout(struct drm_crtc *crtc, struct drm_framebuffer *fb)
end = start + (crtc->mode.vdisplay * fb->pitches[0]);
tilcdc_write(dev, LCDC_DMA_FB_BASE_ADDR_0_REG, start);
tilcdc_write(dev, LCDC_DMA_FB_CEILING_ADDR_0_REG, end);
tilcdc_write(dev, LCDC_DMA_FB_CEILING_ADDR_0_REG, end - 1);
if (tilcdc_crtc->curr_fb)
drm_flip_work_queue(&tilcdc_crtc->unref_work,