Commit e7031d82 authored by Nicholas Kazlauskas's avatar Nicholas Kazlauskas Committed by Alex Deucher
Browse files

drm/amd/display: Add pstate verification and recovery for DCN31 



[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: default avatarNicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Reviewed-by: default avatarEric Yang <Eric.Yang2@amd.com>
Reviewed-by: default avatarHarry Wentland <harry.wentland@amd.com>
Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
parent 65722ff6

drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hubbub.c

+1 −0
Original line number Diff line number Diff line
@@ -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,

drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c

+7 −3
Original line number Diff line number Diff line
@@ -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)
@@ -1124,7 +1128,7 @@ void dcn10_verify_allow_pstate_change_high(struct dc *dc) 
		BREAK_TO_DEBUGGER();

		if (dcn10_hw_wa_force_recovery(dc)) {

			/*check again*/

			if (!hubbub1_verify_allow_pstate_change_high(dc->res_pool->hubbub))

			if (!hubbub->funcs->verify_allow_pstate_change_high(hubbub))

				BREAK_TO_DEBUGGER();

		}

	}

drivers/gpu/drm/amd/display/dc/dcn30/dcn30_hubbub.c

+1 −0
Original line number Diff line number Diff line
@@ -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,

drivers/gpu/drm/amd/display/dc/dcn301/dcn301_hubbub.c

+1 −0
Original line number Diff line number Diff line
@@ -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,

drivers/gpu/drm/amd/display/dc/dcn31/dcn31_hubbub.c

+60 −0
Original line number Diff line number Diff line
@@ -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,