Commit 1bd3bc74 authored by Qingqing Zhuo's avatar Qingqing Zhuo Committed by Alex Deucher
Browse files

drm/amd/display: Extend w/a for hard hang on HPD to dcn20 



[Why]
HPD disable and enable sequences are not mutually exclusive on Linux.
For HPDs that spans under 1s (i.e. HPD low = 1s), part of the disable
sequence (specifically, a request to SMU to lower refclk) could come
right before the call to PHY enablement, causing DMUB to access an
irresponsive PHY and thus a hard hang on the system.

[How]
Disable 48mhz refclk off when there is any HPD status in connected state
for dcn20.

Reviewed-by: default avatarHersen Wu <hersenxs.wu@amd.com>
Acked-by: default avatarRodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: default avatarQingqing Zhuo <qingqing.zhuo@amd.com>
Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
parent a62427ef

drivers/gpu/drm/amd/display/dc/clk_mgr/dcn20/dcn20_clk_mgr.c

+11 −1
Original line number Diff line number Diff line
@@ -38,6 +38,8 @@ 
#include "clk/clk_11_0_0_offset.h"

#include "clk/clk_11_0_0_sh_mask.h"



#include "irq/dcn20/irq_service_dcn20.h"



#undef FN

#define FN(reg_name, field_name) \

	clk_mgr->clk_mgr_shift->field_name, clk_mgr->clk_mgr_mask->field_name
@@ -221,6 +223,8 @@ void dcn2_update_clocks(struct clk_mgr *clk_mgr_base, 
	bool force_reset = false;

	bool p_state_change_support;

	int total_plane_count;

	int irq_src;

	uint32_t hpd_state;



	if (dc->work_arounds.skip_clock_update)

		return;
@@ -238,7 +242,13 @@ void dcn2_update_clocks(struct clk_mgr *clk_mgr_base, 
	if (dc->res_pool->pp_smu)

		pp_smu = &dc->res_pool->pp_smu->nv_funcs;



	if (display_count == 0)

	for (irq_src = DC_IRQ_SOURCE_HPD1; irq_src <= DC_IRQ_SOURCE_HPD6; irq_src++) {

		hpd_state = dal_get_hpd_state_dcn20(dc->res_pool->irqs, irq_src);

		if (hpd_state)

			break;

	}



	if (display_count == 0 && !hpd_state)

		enter_display_off = true;



	if (enter_display_off == safe_to_lower) {

drivers/gpu/drm/amd/display/dc/irq/dcn20/irq_service_dcn20.c

+25 −0
Original line number Diff line number Diff line
@@ -132,6 +132,31 @@ enum dc_irq_source to_dal_irq_source_dcn20( 
	}

}



uint32_t dal_get_hpd_state_dcn20(struct irq_service *irq_service, enum dc_irq_source source)

{

	const struct irq_source_info *info;

	uint32_t addr;

	uint32_t value;

	uint32_t current_status;



	info = find_irq_source_info(irq_service, source);

	if (!info)

		return 0;



	addr = info->status_reg;

	if (!addr)

		return 0;



	value = dm_read_reg(irq_service->ctx, addr);

	current_status =

		get_reg_field_value(

			value,

			HPD0_DC_HPD_INT_STATUS,

			DC_HPD_SENSE);



	return current_status;

}



static bool hpd_ack(

	struct irq_service *irq_service,

	const struct irq_source_info *info)

drivers/gpu/drm/amd/display/dc/irq/dcn20/irq_service_dcn20.h

+2 −0
Original line number Diff line number Diff line
@@ -31,4 +31,6 @@ 
struct irq_service *dal_irq_service_dcn20_create(

	struct irq_service_init_data *init_data);



uint32_t dal_get_hpd_state_dcn20(struct irq_service *irq_service, enum dc_irq_source source);



#endif