HUBP only exists on DCN. On ASICs that use DCE, such as Vega20, the display
pipe never owns a HUBP, so pipe_ctx->plane_res.hubp stays NULL.
The block sequence rework now fills mpcc_id inside the generic helpers in
dc_hw_sequencer.c by reading pipe_ctx->plane_res.hubp->inst. On a DCE ASIC
that read follows the NULL pointer and faults at offset 0x88, where the
inst field sits in struct hubp, and the box dies on the first modeset:
BUG: kernel NULL pointer dereference, address: 0000000000000088
#PF: supervisor read access in kernel mode
Oops: 0000 [#1] SMP NOPTI
CPU: 14 UID: 0 PID: 531 Comm: plymouthd Not tainted 7.1.0 #70
RIP: 0010:hwss_set_output_transfer_func+0x69/0xc0 [amdgpu]
Call Trace:
dce110_program_front_end_for_pipe+0x4d7/0x5c0 [amdgpu]
dce110_apply_ctx_for_surface+0xf1/0x270 [amdgpu]
commit_planes_for_stream+0xba1/0x1c80 [amdgpu]
update_planes_and_stream_v2+0x297/0x6f0 [amdgpu]
dc_update_state_prepare+0x6f/0x1c0 [amdgpu]
dc_update_state+0x41/0x60 [amdgpu]
dc_update_planes_and_stream+0x43/0x70 [amdgpu]
amdgpu_dm_atomic_commit_tail+0x1a6f/0x4120 [amdgpu]
commit_tail+0xc5/0x1a0
drm_atomic_helper_commit+0x137/0x160
drm_atomic_commit+0xaf/0xf0
drm_client_modeset_commit_atomic+0x1ec/0x230
drm_client_modeset_commit_locked+0x5b/0x170
drm_client_modeset_commit+0x27/0x50
__drm_fb_helper_restore_fbdev_mode_unlocked+0xe8/0x110
drm_fbdev_client_restore+0x12/0x20
drm_client_dev_restore+0xbb/0x100
DCE never uses mpcc_id, so 0 is a fine value when there is no HUBP. Add a
small helper that returns the HUBP instance, or 0 when it is missing, and
use it for every mpcc_id assignment. DCN is unchanged since HUBP is always
there.
Fixes: f879f53407f0 ("drm/amd/display: Refactor DPP_SET_OUTPUT_TRANSFER_FUNC to
drop pipe_ctx")
Fixes: 9403e15b2ab1 ("drm/amd/display: Refactor DPP_PROGRAM_GAMUT_REMAP to drop
pipe_ctx param")
Cc: Tomasz Siemek <[email protected]>
Cc: Wayne Lin <[email protected]>
Cc: Alvin Lee <[email protected]>
Signed-off-by: Honglei Huang <[email protected]>
---
.../drm/amd/display/dc/core/dc_hw_sequencer.c | 26 +++++++++++++------
1 file changed, 18 insertions(+), 8 deletions(-)
diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_hw_sequencer.c
b/drivers/gpu/drm/amd/display/dc/core/dc_hw_sequencer.c
index 11411fa946..7676aa4485 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_hw_sequencer.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_hw_sequencer.c
@@ -729,6 +729,16 @@ void get_fams2_visual_confirm_color(
}
}
+/*
+ * Return the MPCC instance for a pipe. On DCN it matches the HUBP instance.
+ * DCE has no HUBP and ignores mpcc_id, so return 0 there instead of chasing a
+ * NULL pointer.
+ */
+static int hwss_pipe_mpcc_id(const struct pipe_ctx *pipe_ctx)
+{
+ return pipe_ctx->plane_res.hubp ? pipe_ctx->plane_res.hubp->inst : 0;
+}
+
void hwss_build_fast_sequence(struct dc *dc,
struct dc_dmub_cmd *dc_dmub_cmd,
unsigned int dmub_cmd_count,
@@ -1073,7 +1083,7 @@ void hwss_build_fast_sequence(struct dc *dc,
params->dpp =
current_mpc_pipe->plane_res.dpp;
params->mpc = dc->res_pool->mpc;
params->xfm =
current_mpc_pipe->plane_res.xfm;
- params->mpcc_id =
current_mpc_pipe->plane_res.hubp->inst;
+ params->mpcc_id =
hwss_pipe_mpcc_id(current_mpc_pipe);
params->plane =
current_mpc_pipe->plane_state;
params->stream =
current_mpc_pipe->stream;
params->is_top_pipe =
current_mpc_pipe->top_pipe == NULL;
@@ -1118,7 +1128,7 @@ void hwss_build_fast_sequence(struct dc *dc,
otf_params->dpp =
current_mpc_pipe->plane_res.dpp;
otf_params->xfm =
current_mpc_pipe->plane_res.xfm;
otf_params->mpc = dc->res_pool->mpc;
- otf_params->mpcc_id =
current_mpc_pipe->plane_res.hubp->inst;
+ otf_params->mpcc_id =
hwss_pipe_mpcc_id(current_mpc_pipe);
otf_params->is_top_pipe =
resource_is_pipe_type(current_mpc_pipe, OPP_HEAD);
otf_params->stream = current_mpc_pipe->stream;
block_sequence[*num_steps].func =
DPP_SET_OUTPUT_TRANSFER_FUNC;
@@ -1128,13 +1138,13 @@ void hwss_build_fast_sequence(struct dc *dc,
dc->hwss.update_visual_confirm_color) {
block_sequence[*num_steps].params.update_visual_confirm_params.dc = dc;
block_sequence[*num_steps].params.update_visual_confirm_params.pipe_ctx =
current_mpc_pipe;
-
block_sequence[*num_steps].params.update_visual_confirm_params.mpcc_id =
current_mpc_pipe->plane_res.hubp->inst;
+
block_sequence[*num_steps].params.update_visual_confirm_params.mpcc_id =
hwss_pipe_mpcc_id(current_mpc_pipe);
block_sequence[*num_steps].func =
MPC_UPDATE_VISUAL_CONFIRM;
(*num_steps)++;
}
if
(current_mpc_pipe->stream->update_flags.bits.out_csc) {
block_sequence[*num_steps].params.power_on_mpc_mem_pwr_params.mpc =
dc->res_pool->mpc;
-
block_sequence[*num_steps].params.power_on_mpc_mem_pwr_params.mpcc_id =
current_mpc_pipe->plane_res.hubp->inst;
+
block_sequence[*num_steps].params.power_on_mpc_mem_pwr_params.mpcc_id =
hwss_pipe_mpcc_id(current_mpc_pipe);
block_sequence[*num_steps].params.power_on_mpc_mem_pwr_params.power_on = true;
block_sequence[*num_steps].func =
MPC_POWER_ON_MPC_MEM_PWR;
(*num_steps)++;
@@ -1837,7 +1847,7 @@ void hwss_add_dpp_program_gamut_remap(struct
block_sequence_state *seq_state,
params->xfm = pipe_ctx->plane_res.xfm;
params->dpp = pipe_ctx->plane_res.dpp;
params->mpc = pipe_ctx->stream->ctx->dc->res_pool->mpc;
- params->mpcc_id = pipe_ctx->plane_res.hubp->inst;
+ params->mpcc_id = hwss_pipe_mpcc_id(pipe_ctx);
params->plane = pipe_ctx->plane_state;
params->stream = pipe_ctx->stream;
params->is_top_pipe = pipe_ctx->top_pipe == NULL;
@@ -1883,7 +1893,7 @@ void hwss_add_dpp_set_output_transfer_func(struct
block_sequence_state *seq_stat
.xfm = pipe_ctx->plane_res.xfm,
.dpp = pipe_ctx->plane_res.dpp,
.mpc = dc->res_pool->mpc,
- .mpcc_id = pipe_ctx->plane_res.hubp->inst,
+ .mpcc_id = hwss_pipe_mpcc_id(pipe_ctx),
.is_top_pipe = resource_is_pipe_type(pipe_ctx,
OPP_HEAD),
.stream = pipe_ctx->stream,
};
@@ -1900,7 +1910,7 @@ void hwss_set_output_transfer_func(struct dc *dc, struct
pipe_ctx *pipe_ctx)
.xfm = pipe_ctx->plane_res.xfm,
.dpp = pipe_ctx->plane_res.dpp,
.mpc = dc->res_pool->mpc,
- .mpcc_id = pipe_ctx->plane_res.hubp->inst,
+ .mpcc_id = hwss_pipe_mpcc_id(pipe_ctx),
.is_top_pipe = resource_is_pipe_type(pipe_ctx,
OPP_HEAD),
.stream = pipe_ctx->stream,
}
@@ -3840,7 +3850,7 @@ void hwss_program_gamut_remap(struct pipe_ctx *pipe_ctx)
.xfm = pipe_ctx->plane_res.xfm,
.dpp = pipe_ctx->plane_res.dpp,
.mpc = dc->res_pool->mpc,
- .mpcc_id = pipe_ctx->plane_res.hubp->inst,
+ .mpcc_id = hwss_pipe_mpcc_id(pipe_ctx),
.stream = pipe_ctx->stream,
.plane = pipe_ctx->plane_state,
.is_top_pipe = pipe_ctx->top_pipe == NULL,
--
2.34.1
