On 2022-03-09 14:19, Nicholas Kazlauskas wrote:
> [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.kazlaus...@amd.com>
> Reviewed-by: Eric Yang <eric.ya...@amd.com>
Reviewed-by: Harry Wentland <harry.wentl...@amd.com>
Harry
> ---
> .../drm/amd/display/dc/dcn10/dcn10_hubbub.c | 1 +
> .../amd/display/dc/dcn10/dcn10_hw_sequencer.c | 10 +++-
> .../drm/amd/display/dc/dcn30/dcn30_hubbub.c | 1 +
> .../drm/amd/display/dc/dcn301/dcn301_hubbub.c | 1 +
> .../drm/amd/display/dc/dcn31/dcn31_hubbub.c | 60 +++++++++++++++++++
> .../drm/amd/display/dc/dcn31/dcn31_resource.c | 2 +-
> .../gpu/drm/amd/display/dc/inc/hw/dchubbub.h | 2 +
> 7 files changed, 73 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hubbub.c
> b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hubbub.c
> index f4f423d0b8c3..80595d7f060c 100644
> --- 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_funcs = {
> .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,
> diff --git a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c
> b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c
> index bc9dd48258e3..c3e141c19a77 100644
> --- 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(struct dc *dc)
>
> 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_high(struct dc
> *dc)
> 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();
> }
> }
> diff --git a/drivers/gpu/drm/amd/display/dc/dcn30/dcn30_hubbub.c
> b/drivers/gpu/drm/amd/display/dc/dcn30/dcn30_hubbub.c
> index f4414de96acc..152c9c5733f1 100644
> --- 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 hubbub30_funcs = {
> .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,
> diff --git a/drivers/gpu/drm/amd/display/dc/dcn301/dcn301_hubbub.c
> b/drivers/gpu/drm/amd/display/dc/dcn301/dcn301_hubbub.c
> index 1e3bd2e9cdcc..a046664e2031 100644
> --- 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 hubbub301_funcs = {
> .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,
> diff --git a/drivers/gpu/drm/amd/display/dc/dcn31/dcn31_hubbub.c
> b/drivers/gpu/drm/amd/display/dc/dcn31/dcn31_hubbub.c
> index 5e3bcaf12cac..3e6d6ebd199e 100644
> --- 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(struct hubbub
> *hubbub,
> }
> }
>
> +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 hubbub31_funcs = {
> .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,
> diff --git a/drivers/gpu/drm/amd/display/dc/dcn31/dcn31_resource.c
> b/drivers/gpu/drm/amd/display/dc/dcn31/dcn31_resource.c
> index 7dbe301a994a..89b7b6b7254a 100644
> --- 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 debug_defaults_drv
> = {
> .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,
> diff --git a/drivers/gpu/drm/amd/display/dc/inc/hw/dchubbub.h
> b/drivers/gpu/drm/amd/display/dc/inc/hw/dchubbub.h
> index 713f5558f5e1..9195dec294c2 100644
> --- 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);
