From 1ce65f5284d6018916dd4a86865d0ce5f11d24b9 Mon Sep 17 00:00:00 2001 From: Harry Wentland Date: Fri, 31 Mar 2017 20:14:33 -0400 Subject: drm/amdgpu: Read vram width from integrated system info table On KB, KV, CZ we should read the vram width from integrated system table, if we can. The NOOFCHAN in MC_SHARED_CHMAP is not accurate. With this change we can enable two 4k displays on CZ again. This use case was broken sometime in January when we started looking at vram_width for bandwidth calculations instead of hardcoding this value. v2: Return 0 if integrated system info table is not available. Tested-by: Roman Li Signed-off-by: Harry Wentland Reviewed-by: Alex Deucher Signed-off-by: Alex Deucher --- drivers/gpu/drm/amd/amdgpu/amdgpu_atombios.c | 29 ++++++++++++++++++++++++++++ 1 file changed, 29 insertions(+) (limited to 'drivers/gpu/drm/amd/amdgpu/amdgpu_atombios.c') diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_atombios.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_atombios.c index f52b1bf3d3d9..ad4329922f79 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_atombios.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_atombios.c @@ -754,6 +754,35 @@ union igp_info { struct _ATOM_INTEGRATED_SYSTEM_INFO_V1_9 info_9; }; +/* + * Return vram width from integrated system info table, if available, + * or 0 if not. + */ +int amdgpu_atombios_get_vram_width(struct amdgpu_device *adev) +{ + struct amdgpu_mode_info *mode_info = &adev->mode_info; + int index = GetIndexIntoMasterTable(DATA, IntegratedSystemInfo); + u16 data_offset, size; + union igp_info *igp_info; + u8 frev, crev; + + /* get any igp specific overrides */ + if (amdgpu_atom_parse_data_header(mode_info->atom_context, index, &size, + &frev, &crev, &data_offset)) { + igp_info = (union igp_info *) + (mode_info->atom_context->bios + data_offset); + switch (crev) { + case 8: + case 9: + return igp_info->info_8.ucUMAChannelNumber * 64; + default: + return 0; + } + } + + return 0; +} + static void amdgpu_atombios_get_igp_ss_overrides(struct amdgpu_device *adev, struct amdgpu_atom_ss *ss, int id) -- cgit v1.2.3-70-g09d2