From: Sam Bobroff sbobroff@linux.ibm.com
[ Upstream commit 3d0e3ce52ce3eb4b9de3caf9c38dbb5a4d3e13c3 ]
The INTERRUPT_CNTL2 register expects a valid DMA address, but is currently set with a GPU MC address. This can cause problems on systems that detect the resulting DMA read from an invalid address (found on a Power8 guest).
Instead, use the DMA address of the dummy page because it will always be safe.
Fixes: 27ae10641e9c ("drm/amdgpu: add interupt handler implementation for si v3") Signed-off-by: Sam Bobroff sbobroff@linux.ibm.com Signed-off-by: Alex Deucher alexander.deucher@amd.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/amd/amdgpu/si_ih.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/amd/amdgpu/si_ih.c b/drivers/gpu/drm/amd/amdgpu/si_ih.c index 57bb5f9e08b2d..88ae27a5a03db 100644 --- a/drivers/gpu/drm/amd/amdgpu/si_ih.c +++ b/drivers/gpu/drm/amd/amdgpu/si_ih.c @@ -64,7 +64,8 @@ static int si_ih_irq_init(struct amdgpu_device *adev) u32 interrupt_cntl, ih_cntl, ih_rb_cntl;
si_ih_disable_interrupts(adev); - WREG32(INTERRUPT_CNTL2, adev->irq.ih.gpu_addr >> 8); + /* set dummy read address to dummy page address */ + WREG32(INTERRUPT_CNTL2, adev->dummy_page_addr >> 8); interrupt_cntl = RREG32(INTERRUPT_CNTL); interrupt_cntl &= ~IH_DUMMY_RD_OVERRIDE; interrupt_cntl &= ~IH_REQ_NONSNOOP_EN;