drm/amd/display: Apply w/a for hard hang on HPD

[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.

Reviewed-by: Hersen Wu <hersenwu@amd.com>
Acked-by: Mikita Lipski <mikita.lipski@amd.com>
Signed-off-by: Qingqing Zhuo <qingqing.zhuo@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn21/rn_clk_mgr.c b/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn21/rn_clk_mgr.c
index c6f494f0dcea3e49e56bf5843494794ae0f67669..3fabf32a055842538581691ca4bfaf133cedf155 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn21/rn_clk_mgr.c
+++ b/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn21/rn_clk_mgr.c
@@ -42,6 +42,7 @@
 #include "clk/clk_10_0_2_sh_mask.h"
 #include "renoir_ip_offset.h"
 
+#include "irq/dcn21/irq_service_dcn21.h"
 
 /* Constants */
 
@@ -129,9 +130,11 @@ void rn_update_clocks(struct clk_mgr *clk_mgr_base,
        struct dc_clocks *new_clocks = &context->bw_ctx.bw.dcn.clk;
        struct dc *dc = clk_mgr_base->ctx->dc;
        int display_count;
+       int irq_src;
        bool update_dppclk = false;
        bool update_dispclk = false;
        bool dpp_clock_lowered = false;
+       uint32_t hpd_state;
 
        struct dmcu *dmcu = clk_mgr_base->ctx->dc->res_pool->dmcu;
 
@@ -147,8 +150,15 @@ void rn_update_clocks(struct clk_mgr *clk_mgr_base,
                if (clk_mgr_base->clks.pwr_state != DCN_PWR_STATE_LOW_POWER) {
 
                        display_count = rn_get_active_display_cnt_wa(dc, context);
+
+                       for (irq_src = DC_IRQ_SOURCE_HPD1; irq_src <= DC_IRQ_SOURCE_HPD5; irq_src++) {
+                               hpd_state = dal_get_hpd_state_dcn21(dc->res_pool->irqs, irq_src);
+                               if (hpd_state)
+                                       break;
+                       }
+
                        /* if we can go lower, go lower */
-                       if (display_count == 0) {
+                       if (display_count == 0 && !hpd_state) {
                                rn_vbios_smu_set_dcn_low_power_state(clk_mgr, DCN_PWR_STATE_LOW_POWER);
                                /* update power state */
                                clk_mgr_base->clks.pwr_state = DCN_PWR_STATE_LOW_POWER;

diff --git a/drivers/gpu/drm/amd/display/dc/irq/dcn21/irq_service_dcn21.c b/drivers/gpu/drm/amd/display/dc/irq/dcn21/irq_service_dcn21.c
index ed54e1c819beda7b13e371249f21adf65205133b..685528734575d517b2c13e1f5e997ed620c0797f 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/irq/dcn21/irq_service_dcn21.c
+++ b/drivers/gpu/drm/amd/display/dc/irq/dcn21/irq_service_dcn21.c
@@ -135,6 +135,31 @@ enum dc_irq_source to_dal_irq_source_dcn21(
        return DC_IRQ_SOURCE_INVALID;
 }
 
+uint32_t dal_get_hpd_state_dcn21(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)

diff --git a/drivers/gpu/drm/amd/display/dc/irq/dcn21/irq_service_dcn21.h b/drivers/gpu/drm/amd/display/dc/irq/dcn21/irq_service_dcn21.h
index da2bd0e93d7ad9451260011a723b1a7609d97469..3df2ceeb2b706d738b81f83a3302334019315ec4 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/irq/dcn21/irq_service_dcn21.h
+++ b/drivers/gpu/drm/amd/display/dc/irq/dcn21/irq_service_dcn21.h
@@ -31,4 +31,6 @@
 struct irq_service *dal_irq_service_dcn21_create(
        struct irq_service_init_data *init_data);
 
+uint32_t dal_get_hpd_state_dcn21(struct irq_service *irq_service, enum dc_irq_source source);
+
 #endif

diff --git a/drivers/gpu/drm/amd/display/dc/irq/irq_service.c b/drivers/gpu/drm/amd/display/dc/irq/irq_service.c
index a2a4fbeb83f86c3d4620fb996e417a892b704ee9..4db1133e4466be1f9146d7b87f85ed58aa218dca 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/irq/irq_service.c
+++ b/drivers/gpu/drm/amd/display/dc/irq/irq_service.c
@@ -79,7 +79,7 @@ void dal_irq_service_destroy(struct irq_service **irq_service)
        *irq_service = NULL;
 }
 
-static const struct irq_source_info *find_irq_source_info(
+const struct irq_source_info *find_irq_source_info(
        struct irq_service *irq_service,
        enum dc_irq_source source)
 {

diff --git a/drivers/gpu/drm/amd/display/dc/irq/irq_service.h b/drivers/gpu/drm/amd/display/dc/irq/irq_service.h
index dbfcb096eedd684593cddb66a151d812b68ab50a..e60b824800932c48ea9b0ea89cd6b6e7c3421788 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/irq/irq_service.h
+++ b/drivers/gpu/drm/amd/display/dc/irq/irq_service.h
@@ -69,6 +69,10 @@ struct irq_service {
        const struct irq_service_funcs *funcs;
 };
 
+const struct irq_source_info *find_irq_source_info(
+       struct irq_service *irq_service,
+       enum dc_irq_source source);
+
 void dal_irq_service_construct(
        struct irq_service *irq_service,
        struct irq_service_init_data *init_data);