--- /dev/null
+From e7031d8258f1b4d6d50e5e5b5d92ba16f66eb8b4 Mon Sep 17 00:00:00 2001
+From: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
+Date: Fri, 17 Dec 2021 09:55:54 -0500
+Subject: drm/amd/display: Add pstate verification and recovery for DCN31
+
+From: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
+
+commit e7031d8258f1b4d6d50e5e5b5d92ba16f66eb8b4 upstream.
+
+[Why]
+To debug when p-state is being blocked and avoid PMFW hangs when
+it does occur.
+
+[How]
+Re-use the DCN10 hardware sequencer by adding a new interface for
+verifying p-state high on the hubbub. The interface is mostly the
+same as the DCN10 interface, but the bit definitions have changed for
+the debug bus.
+
+Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
+Reviewed-by: Eric Yang <Eric.Yang2@amd.com>
+Reviewed-by: Harry Wentland <harry.wentland@amd.com>
+Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hubbub.c | 1
+ drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c | 10 +-
+ drivers/gpu/drm/amd/display/dc/dcn30/dcn30_hubbub.c | 1
+ drivers/gpu/drm/amd/display/dc/dcn301/dcn301_hubbub.c | 1
+ drivers/gpu/drm/amd/display/dc/dcn31/dcn31_hubbub.c | 60 ++++++++++++++
+ drivers/gpu/drm/amd/display/dc/dcn31/dcn31_resource.c | 2
+ drivers/gpu/drm/amd/display/dc/inc/hw/dchubbub.h | 2
+ 7 files changed, 73 insertions(+), 4 deletions(-)
+
+--- a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hubbub.c
++++ b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hubbub.c
+@@ -940,6 +940,7 @@ static const struct hubbub_funcs hubbub1
+ .program_watermarks = hubbub1_program_watermarks,
+ .is_allow_self_refresh_enabled = hubbub1_is_allow_self_refresh_enabled,
+ .allow_self_refresh_control = hubbub1_allow_self_refresh_control,
++ .verify_allow_pstate_change_high = hubbub1_verify_allow_pstate_change_high,
+ };
+
+ void hubbub1_construct(struct hubbub *hubbub,
+--- a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c
++++ b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c
+@@ -1112,9 +1112,13 @@ static bool dcn10_hw_wa_force_recovery(s
+
+ void dcn10_verify_allow_pstate_change_high(struct dc *dc)
+ {
++ struct hubbub *hubbub = dc->res_pool->hubbub;
+ static bool should_log_hw_state; /* prevent hw state log by default */
+
+- if (!hubbub1_verify_allow_pstate_change_high(dc->res_pool->hubbub)) {
++ if (!hubbub->funcs->verify_allow_pstate_change_high)
++ return;
++
++ if (!hubbub->funcs->verify_allow_pstate_change_high(hubbub)) {
+ int i = 0;
+
+ if (should_log_hw_state)
+@@ -1123,8 +1127,8 @@ void dcn10_verify_allow_pstate_change_hi
+ TRACE_DC_PIPE_STATE(pipe_ctx, i, MAX_PIPES);
+ BREAK_TO_DEBUGGER();
+ if (dcn10_hw_wa_force_recovery(dc)) {
+- /*check again*/
+- if (!hubbub1_verify_allow_pstate_change_high(dc->res_pool->hubbub))
++ /*check again*/
++ if (!hubbub->funcs->verify_allow_pstate_change_high(hubbub))
+ BREAK_TO_DEBUGGER();
+ }
+ }
+--- a/drivers/gpu/drm/amd/display/dc/dcn30/dcn30_hubbub.c
++++ b/drivers/gpu/drm/amd/display/dc/dcn30/dcn30_hubbub.c
+@@ -448,6 +448,7 @@ static const struct hubbub_funcs hubbub3
+ .program_watermarks = hubbub3_program_watermarks,
+ .allow_self_refresh_control = hubbub1_allow_self_refresh_control,
+ .is_allow_self_refresh_enabled = hubbub1_is_allow_self_refresh_enabled,
++ .verify_allow_pstate_change_high = hubbub1_verify_allow_pstate_change_high,
+ .force_wm_propagate_to_pipes = hubbub3_force_wm_propagate_to_pipes,
+ .force_pstate_change_control = hubbub3_force_pstate_change_control,
+ .init_watermarks = hubbub3_init_watermarks,
+--- a/drivers/gpu/drm/amd/display/dc/dcn301/dcn301_hubbub.c
++++ b/drivers/gpu/drm/amd/display/dc/dcn301/dcn301_hubbub.c
+@@ -60,6 +60,7 @@ static const struct hubbub_funcs hubbub3
+ .program_watermarks = hubbub3_program_watermarks,
+ .allow_self_refresh_control = hubbub1_allow_self_refresh_control,
+ .is_allow_self_refresh_enabled = hubbub1_is_allow_self_refresh_enabled,
++ .verify_allow_pstate_change_high = hubbub1_verify_allow_pstate_change_high,
+ .force_wm_propagate_to_pipes = hubbub3_force_wm_propagate_to_pipes,
+ .force_pstate_change_control = hubbub3_force_pstate_change_control,
+ .hubbub_read_state = hubbub2_read_state,
+--- a/drivers/gpu/drm/amd/display/dc/dcn31/dcn31_hubbub.c
++++ b/drivers/gpu/drm/amd/display/dc/dcn31/dcn31_hubbub.c
+@@ -949,6 +949,65 @@ static void hubbub31_get_dchub_ref_freq(
+ }
+ }
+
++static bool hubbub31_verify_allow_pstate_change_high(struct hubbub *hubbub)
++{
++ struct dcn20_hubbub *hubbub2 = TO_DCN20_HUBBUB(hubbub);
++
++ /*
++ * Pstate latency is ~20us so if we wait over 40us and pstate allow
++ * still not asserted, we are probably stuck and going to hang
++ */
++ const unsigned int pstate_wait_timeout_us = 100;
++ const unsigned int pstate_wait_expected_timeout_us = 40;
++
++ static unsigned int max_sampled_pstate_wait_us; /* data collection */
++ static bool forced_pstate_allow; /* help with revert wa */
++
++ unsigned int debug_data = 0;
++ unsigned int i;
++
++ if (forced_pstate_allow) {
++ /* we hacked to force pstate allow to prevent hang last time
++ * we verify_allow_pstate_change_high. so disable force
++ * here so we can check status
++ */
++ REG_UPDATE_2(DCHUBBUB_ARB_DRAM_STATE_CNTL,
++ DCHUBBUB_ARB_ALLOW_PSTATE_CHANGE_FORCE_VALUE, 0,
++ DCHUBBUB_ARB_ALLOW_PSTATE_CHANGE_FORCE_ENABLE, 0);
++ forced_pstate_allow = false;
++ }
++
++ REG_WRITE(DCHUBBUB_TEST_DEBUG_INDEX, hubbub2->debug_test_index_pstate);
++
++ for (i = 0; i < pstate_wait_timeout_us; i++) {
++ debug_data = REG_READ(DCHUBBUB_TEST_DEBUG_DATA);
++
++ /* Debug bit is specific to ASIC. */
++ if (debug_data & (1 << 26)) {
++ if (i > pstate_wait_expected_timeout_us)
++ DC_LOG_WARNING("pstate took longer than expected ~%dus\n", i);
++ return true;
++ }
++ if (max_sampled_pstate_wait_us < i)
++ max_sampled_pstate_wait_us = i;
++
++ udelay(1);
++ }
++
++ /* force pstate allow to prevent system hang
++ * and break to debugger to investigate
++ */
++ REG_UPDATE_2(DCHUBBUB_ARB_DRAM_STATE_CNTL,
++ DCHUBBUB_ARB_ALLOW_PSTATE_CHANGE_FORCE_VALUE, 1,
++ DCHUBBUB_ARB_ALLOW_PSTATE_CHANGE_FORCE_ENABLE, 1);
++ forced_pstate_allow = true;
++
++ DC_LOG_WARNING("pstate TEST_DEBUG_DATA: 0x%X\n",
++ debug_data);
++
++ return false;
++}
++
+ static const struct hubbub_funcs hubbub31_funcs = {
+ .update_dchub = hubbub2_update_dchub,
+ .init_dchub_sys_ctx = hubbub31_init_dchub_sys_ctx,
+@@ -961,6 +1020,7 @@ static const struct hubbub_funcs hubbub3
+ .program_watermarks = hubbub31_program_watermarks,
+ .allow_self_refresh_control = hubbub1_allow_self_refresh_control,
+ .is_allow_self_refresh_enabled = hubbub1_is_allow_self_refresh_enabled,
++ .verify_allow_pstate_change_high = hubbub31_verify_allow_pstate_change_high,
+ .program_det_size = dcn31_program_det_size,
+ .program_compbuf_size = dcn31_program_compbuf_size,
+ .init_crb = dcn31_init_crb,
+--- a/drivers/gpu/drm/amd/display/dc/dcn31/dcn31_resource.c
++++ b/drivers/gpu/drm/amd/display/dc/dcn31/dcn31_resource.c
+@@ -1011,7 +1011,7 @@ static const struct dc_debug_options deb
+ .max_downscale_src_width = 4096,/*upto true 4K*/
+ .disable_pplib_wm_range = false,
+ .scl_reset_length10 = true,
+- .sanity_checks = false,
++ .sanity_checks = true,
+ .underflow_assert_delay_us = 0xFFFFFFFF,
+ .dwb_fi_phase = -1, // -1 = disable,
+ .dmub_command_table = true,
+--- a/drivers/gpu/drm/amd/display/dc/inc/hw/dchubbub.h
++++ b/drivers/gpu/drm/amd/display/dc/inc/hw/dchubbub.h
+@@ -154,6 +154,8 @@ struct hubbub_funcs {
+ bool (*is_allow_self_refresh_enabled)(struct hubbub *hubbub);
+ void (*allow_self_refresh_control)(struct hubbub *hubbub, bool allow);
+
++ bool (*verify_allow_pstate_change_high)(struct hubbub *hubbub);
++
+ void (*apply_DEDCN21_147_wa)(struct hubbub *hubbub);
+
+ void (*force_wm_propagate_to_pipes)(struct hubbub *hubbub);