[PATCH AUTOSEL 6.1 27/48] drm/amdgpu: clear RB_OVERFLOW bit when enabling interrupts for vega20_ih

[Sasha Levin]

From: Victor Lu <victorchengchi...@amd.com>

[ Upstream commit 8b22f048331dfd45fdfbf0efdfb1d43deff7518d ]

Port this change to vega20_ih.c:
commit afbf7955ff01 ("drm/amdgpu: clear RB_OVERFLOW bit when enabling 
interrupts")

Original commit message:
"Why:
Setting IH_RB_WPTR register to 0 will not clear the RB_OVERFLOW bit
if RB_ENABLE is not set.

How to fix:
Set WPTR_OVERFLOW_CLEAR bit after RB_ENABLE bit is set.
The RB_ENABLE bit is required to be set, together with
WPTR_OVERFLOW_ENABLE bit so that setting WPTR_OVERFLOW_CLEAR bit
would clear the RB_OVERFLOW."

Signed-off-by: Victor Lu <victorchengchi...@amd.com>
Reviewed-by: Alex Deucher <alexander.deuc...@amd.com>
Signed-off-by: Alex Deucher <alexander.deuc...@amd.com>
Signed-off-by: Sasha Levin <sas...@kernel.org>
---
 drivers/gpu/drm/amd/amdgpu/vega20_ih.c | 27 ++++++++++++++++++++++++++
 1 file changed, 27 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/vega20_ih.c 
b/drivers/gpu/drm/amd/amdgpu/vega20_ih.c
index f1ba76c35cd6e..e85a0fb227d4e 100644
--- a/drivers/gpu/drm/amd/amdgpu/vega20_ih.c
+++ b/drivers/gpu/drm/amd/amdgpu/vega20_ih.c
@@ -109,6 +109,33 @@ static int vega20_ih_toggle_ring_interrupts(struct 
amdgpu_device *adev,
        tmp = REG_SET_FIELD(tmp, IH_RB_CNTL, RB_ENABLE, (enable ? 1 : 0));
        tmp = REG_SET_FIELD(tmp, IH_RB_CNTL, RB_GPU_TS_ENABLE, 1);
 
+       if (enable) {
+               /* Unset the CLEAR_OVERFLOW bit to make sure the next step
+                * is switching the bit from 0 to 1
+                */
+               tmp = REG_SET_FIELD(tmp, IH_RB_CNTL, WPTR_OVERFLOW_CLEAR, 0);
+               if (amdgpu_sriov_vf(adev) && 
amdgpu_sriov_reg_indirect_ih(adev)) {
+                       if (psp_reg_program(&adev->psp, ih_regs->psp_reg_id, 
tmp))
+                               return -ETIMEDOUT;
+               } else {
+                       WREG32_NO_KIQ(ih_regs->ih_rb_cntl, tmp);
+               }
+
+               /* Clear RB_OVERFLOW bit */
+               tmp = REG_SET_FIELD(tmp, IH_RB_CNTL, WPTR_OVERFLOW_CLEAR, 1);
+               if (amdgpu_sriov_vf(adev) && 
amdgpu_sriov_reg_indirect_ih(adev)) {
+                       if (psp_reg_program(&adev->psp, ih_regs->psp_reg_id, 
tmp))
+                               return -ETIMEDOUT;
+               } else {
+                       WREG32_NO_KIQ(ih_regs->ih_rb_cntl, tmp);
+               }
+
+               /* Unset the CLEAR_OVERFLOW bit immediately so new overflows
+                * can be detected.
+                */
+               tmp = REG_SET_FIELD(tmp, IH_RB_CNTL, WPTR_OVERFLOW_CLEAR, 0);
+       }
+
        /* enable_intr field is only valid in ring0 */
        if (ih == &adev->irq.ih)
                tmp = REG_SET_FIELD(tmp, IH_RB_CNTL, ENABLE_INTR, (enable ? 1 : 
0));
-- 
2.43.0