diff options
| author | Andres Salomon <dilinger@queued.net> | 2008-04-28 02:15:30 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2008-04-28 08:58:40 -0700 |
| commit | fd96795630428ceca775bd1effc5bf41a9fe5272 (patch) | |
| tree | d14276ebf1ff907711e56e2742e15b594ebd166e /drivers/video/geode/lxfb_ops.c | |
| parent | 61a517a063abf659cbf61df11f8e2131fdafccec (diff) | |
gxfb/lxfb: detect framebuffer size using an MSR if VSA2 isn't available
If there's no VSA2 (ie, if we're using tinybios or OpenFirmware), use the
GLIU's P2D Range Offset Descriptor to determine how much memory we have
available for the framebuffer.
Originally based on a patch by Jordan Crouse. Tested with OpenFirmware;
Pascal informs me that tinybios has a stub that fills in P2D_RO0.
Signed-off-by: Andres Salomon <dilinger@debian.org>
Cc: Jordan Crouse <jordan.crouse@amd.com>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/video/geode/lxfb_ops.c')
| -rw-r--r-- | drivers/video/geode/lxfb_ops.c | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/drivers/video/geode/lxfb_ops.c b/drivers/video/geode/lxfb_ops.c index e42e12489f6..cd9d4cc2695 100644 --- a/drivers/video/geode/lxfb_ops.c +++ b/drivers/video/geode/lxfb_ops.c @@ -329,6 +329,22 @@ unsigned int lx_framebuffer_size(void) { unsigned int val; + if (!geode_has_vsa2()) { + uint32_t hi, lo; + + /* The number of pages is (PMAX - PMIN)+1 */ + rdmsr(MSR_GLIU_P2D_RO0, lo, hi); + + /* PMAX */ + val = ((hi & 0xff) << 12) | ((lo & 0xfff00000) >> 20); + /* PMIN */ + val -= (lo & 0x000fffff); + val += 1; + + /* The page size is 4k */ + return (val << 12); + } + /* The frame buffer size is reported by a VSM in VSA II */ /* Virtual Register Class = 0x02 */ /* VG_MEM_SIZE (1MB units) = 0x00 */ |