From 0ca223b029a261e82fb2f50c52eb85d510f4260e Mon Sep 17 00:00:00 2001 From: Alex Deucher Date: Tue, 3 Dec 2013 09:24:30 -0500 Subject: [PATCH] drm/radeon: fixup bad vram size on SI Some boards seem to have garbage in the upper 16 bits of the vram size register. Check for this and clamp the size properly. Fixes boards reporting bogus amounts of vram. Signed-off-by: Alex Deucher Cc: stable@vger.kernel.org --- drivers/gpu/drm/radeon/si.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/radeon/si.c b/drivers/gpu/drm/radeon/si.c index 6a64ccaa0695..a36736dab5e0 100644 --- a/drivers/gpu/drm/radeon/si.c +++ b/drivers/gpu/drm/radeon/si.c @@ -3882,8 +3882,15 @@ static int si_mc_init(struct radeon_device *rdev) rdev->mc.aper_base = pci_resource_start(rdev->pdev, 0); rdev->mc.aper_size = pci_resource_len(rdev->pdev, 0); /* size in MB on si */ - rdev->mc.mc_vram_size = RREG32(CONFIG_MEMSIZE) * 1024ULL * 1024ULL; - rdev->mc.real_vram_size = RREG32(CONFIG_MEMSIZE) * 1024ULL * 1024ULL; + tmp = RREG32(CONFIG_MEMSIZE); + /* some boards may have garbage in the upper 16 bits */ + if (tmp & 0xffff0000) { + DRM_INFO("Probable bad vram size: 0x%08x\n", tmp); + if (tmp & 0xffff) + tmp &= 0xffff; + } + rdev->mc.mc_vram_size = tmp * 1024ULL * 1024ULL; + rdev->mc.real_vram_size = rdev->mc.mc_vram_size; rdev->mc.visible_vram_size = rdev->mc.aper_size; si_vram_gtt_location(rdev, &rdev->mc); radeon_update_bandwidth_info(rdev);