linux_dsm_epyc7002/drivers/gpu
Paul Parsons 85e290d92b drm/radeon: Fix PCIe lane width calculation
Two years ago I tried an AMD Radeon E8860 embedded GPU with the drm driver.
The dmesg output included driver warnings about an invalid PCIe lane width.
Tracking the problem back led to si_set_pcie_lane_width_in_smc().
The calculation of the lane widths via ATOM_PPLIB_PCIE_LINK_WIDTH_MASK and
ATOM_PPLIB_PCIE_LINK_WIDTH_SHIFT macros did not increment the resulting
value, per the comment in pptable.h ("lanes - 1"), and per usage elsewhere.
Applying the increment silenced the warnings.
The code has not changed since, so either my analysis was incorrect or the
bug has gone unnoticed. Hence submitting this as an RFC.

Acked-by: Christian König <christian.koenig@amd.com>
Acked-by: Chunming Zhou <david1.zhou@amd.com>
Signed-off-by: Paul Parsons <lost.distance@yahoo.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
2018-04-03 13:08:45 -05:00
..
drm drm/radeon: Fix PCIe lane width calculation 2018-04-03 13:08:45 -05:00
host1x gpu: host1x: Use IOMMU groups 2017-12-21 14:52:36 +01:00
ipu-v3 gpu: ipu-v3: prg: avoid possible array underflow 2018-03-15 17:52:08 +01:00
vga vga_switcheroo: Let HDA autosuspend on mux change 2018-03-13 22:58:49 +01:00
Makefile