[PATCH AUTOSEL 5.15 29/33] drm/amd/display: Cap pflip irqs per max otg number

From: Sasha Levin
Date: Tue Feb 15 2022 - 10:33:03 EST


From: Roman Li <Roman.Li@xxxxxxx>

[ Upstream commit 328e34a5ad227399391891d454043e5d73e598d2 ]

[Why]
pflip interrupt order are mapped 1 to 1 to otg id.
e.g. if irq_src=26 corresponds to otg0 then 27->otg1, 28->otg2...

Linux DM registers pflip interrupts per number of crtcs.
In fused pipe case crtc numbers can be less than otg id.

e.g. if one pipe out of 3(otg#0-2) is fused adev->mode_info.num_crtc=2
so DM only registers irq_src 26,27.
This is a bug since if pipe#2 remains unfused DM never gets
otg2 pflip interrupt (irq_src=28)
That may results in gfx failure due to pflip timeout.

[How]
Register pflip interrupts per max num of otg instead of num_crtc

Signed-off-by: Roman Li <Roman.Li@xxxxxxx>
Reviewed-by: Nicholas Kazlauskas <nicholas.kazlauskas@xxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 2 +-
drivers/gpu/drm/amd/display/dc/core/dc.c | 2 ++
drivers/gpu/drm/amd/display/dc/dc.h | 1 +
3 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index 16556ae892d4a..5ae9b8133d6da 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -3230,7 +3230,7 @@ static int dcn10_register_irq_handlers(struct amdgpu_device *adev)

/* Use GRPH_PFLIP interrupt */
for (i = DCN_1_0__SRCID__HUBP0_FLIP_INTERRUPT;
- i <= DCN_1_0__SRCID__HUBP0_FLIP_INTERRUPT + adev->mode_info.num_crtc - 1;
+ i <= DCN_1_0__SRCID__HUBP0_FLIP_INTERRUPT + dc->caps.max_otg_num - 1;
i++) {
r = amdgpu_irq_add_id(adev, SOC15_IH_CLIENTID_DCE, i, &adev->pageflip_irq);
if (r) {
diff --git a/drivers/gpu/drm/amd/display/dc/core/dc.c b/drivers/gpu/drm/amd/display/dc/core/dc.c
index 1860ccc3f4f2c..4fae73478840c 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc.c
@@ -1118,6 +1118,8 @@ struct dc *dc_create(const struct dc_init_data *init_params)

dc->caps.max_dp_protocol_version = DP_VERSION_1_4;

+ dc->caps.max_otg_num = dc->res_pool->res_cap->num_timing_generator;
+
if (dc->res_pool->dmcu != NULL)
dc->versions.dmcu_version = dc->res_pool->dmcu->dmcu_version;
}
diff --git a/drivers/gpu/drm/amd/display/dc/dc.h b/drivers/gpu/drm/amd/display/dc/dc.h
index 3ab52d9a82cf6..e0f58fab5e8ed 100644
--- a/drivers/gpu/drm/amd/display/dc/dc.h
+++ b/drivers/gpu/drm/amd/display/dc/dc.h
@@ -185,6 +185,7 @@ struct dc_caps {
struct dc_color_caps color;
bool vbios_lttpr_aware;
bool vbios_lttpr_enable;
+ uint32_t max_otg_num;
};

struct dc_bug_wa {
--
2.34.1