leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

drm/mgag200: Fix framebuffer base address programming

Browse Source 
Higher bits of the base address of framebuffers weren't being
programmed properly. This caused framebuffers that didn't happen to be
allocated at a low enough address to not be displayed properly.

Signed-off-by: Christopher Harvey <charvey@matrox.com>
Signed-off-by: Mathieu Larouche <mathieu.larouche@matrox.com>
Acked-by: Julia Lemire <jlemire@matrox.com>
Tested-by: Julia Lemire <jlemire@matrox.com>
Cc: stable@vger.kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>
This commit is contained in:
Christopher Harvey 2013-05-08 19:10:38 +00:00 committed by Dave Airlie
parent 3cdc0e8d61
commit 9f1d036648
1 changed files with 24 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

27
drivers/gpu/drm/mgag200/mgag200_mode.c
View File

@ -654,12 +654,26 @@ static void mga_g200wb_commit(struct drm_crtc *crtc)
WREG_DAC(MGA1064_GEN_IO_DATA, tmp);
}
/*
This is how the framebuffer base address is stored in g200 cards:
* Assume @offset is the gpu_addr variable of the framebuffer object
* Then addr is the number of _pixels_ (not bytes) from the start of
VRAM to the first pixel we want to display. (divided by 2 for 32bit
framebuffers)
* addr is stored in the CRTCEXT0, CRTCC and CRTCD registers
addr<20> -> CRTCEXT0<6>
addr<19-16> -> CRTCEXT0<3-0>
addr<15-8> -> CRTCC<7-0>
addr<7-0> -> CRTCD<7-0>
CRTCEXT0 has to be programmed last to trigger an update and make the
new addr variable take effect.
*/
void mga_set_start_address(struct drm_crtc *crtc, unsigned offset)
{
struct mga_device *mdev = crtc->dev->dev_private;
u32 addr;
int count;
u8 crtcext0;
while (RREG8(0x1fda) & 0x08);
while (!(RREG8(0x1fda) & 0x08));
@ -667,10 +681,17 @@ void mga_set_start_address(struct drm_crtc *crtc, unsigned offset)
count = RREG8(MGAREG_VCOUNT) + 2;
while (RREG8(MGAREG_VCOUNT) < count);
addr = offset >> 2;
WREG8(MGAREG_CRTCEXT_INDEX, 0);
crtcext0 = RREG8(MGAREG_CRTCEXT_DATA);
crtcext0 &= 0xB0;
addr = offset / 8;
/* Can't store addresses any higher than that...
but we also don't have more than 16MB of memory, so it should be fine. */
WARN_ON(addr > 0x1fffff);
crtcext0 |= (!!(addr & (1<<20)))<<6;
WREG_CRT(0x0d, (u8)(addr & 0xff));
WREG_CRT(0x0c, (u8)(addr >> 8) & 0xff);
WREG_CRT(0xaf, (u8)(addr >> 16) & 0xf);
WREG_ECRT(0x0, ((u8)(addr >> 16) & 0xf) | crtcext0);
}