drm/amd/display: Enable Request rate limiter during C-State on dcn401

[WHY]
When C-State entry is requested, the rate limiter will be disabled
which can result in high contention in the DCHUB return path.

[HOW]
Enable the rate limiter during C-state requests to prevent contention.

Cc: stable@vger.kernel.org # 6.11+
Reviewed-by: Alvin Lee <alvin.lee2@amd.com>
Signed-off-by: Dillon Varone <dillon.varone@amd.com>
Signed-off-by: Hamza Mahfooz <hamza.mahfooz@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/dml2/dml21/src/dml2_core/dml2_core_dcn4_calcs.c b/drivers/gpu/drm/amd/display/dc/dml2/dml21/src/dml2_core/dml2_core_dcn4_calcs.c
index 92e43a1..601320b 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/dml2/dml21/src/dml2_core/dml2_core_dcn4_calcs.c
+++ b/drivers/gpu/drm/amd/display/dc/dml2/dml21/src/dml2_core/dml2_core_dcn4_calcs.c
@@ -11,6 +11,7 @@
 
 #define DML2_MAX_FMT_420_BUFFER_WIDTH 4096
 #define DML_MAX_NUM_OF_SLICES_PER_DSC 4
+#define ALLOW_SDPIF_RATE_LIMIT_PRE_CSTATE
 
 const char *dml2_core_internal_bw_type_str(enum dml2_core_internal_bw_type bw_type)
 {
@@ -3886,6 +3887,10 @@ static void CalculateSwathAndDETConfiguration(struct dml2_core_internal_scratch
 #endif
 
        *p->hw_debug5 = false;
+#ifdef ALLOW_SDPIF_RATE_LIMIT_PRE_CSTATE
+       if (p->NumberOfActiveSurfaces > 1)
+               *p->hw_debug5 = true;
+#else
        for (unsigned int k = 0; k < p->NumberOfActiveSurfaces; ++k) {
                if (!(p->mrq_present) && (!(*p->UnboundedRequestEnabled)) && (TotalActiveDPP == 1)
                        && p->display_cfg->plane_descriptors[k].surface.dcc.enable
@@ -3901,6 +3906,7 @@ static void CalculateSwathAndDETConfiguration(struct dml2_core_internal_scratch
                dml2_printf("DML::%s: k=%u hw_debug5 = %u\n", __func__, k, *p->hw_debug5);
 #endif
        }
+#endif
 }
 
 static enum dml2_odm_mode DecideODMMode(unsigned int HActive,

diff --git a/drivers/gpu/drm/amd/display/dc/hubbub/dcn10/dcn10_hubbub.h b/drivers/gpu/drm/amd/display/dc/hubbub/dcn10/dcn10_hubbub.h
index 4bd1dda..9fbd45c 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/hubbub/dcn10/dcn10_hubbub.h
+++ b/drivers/gpu/drm/amd/display/dc/hubbub/dcn10/dcn10_hubbub.h
@@ -200,6 +200,7 @@ struct dcn_hubbub_registers {
        uint32_t DCHUBBUB_ARB_FRAC_URG_BW_MALL_B;
        uint32_t DCHUBBUB_TIMEOUT_DETECTION_CTRL1;
        uint32_t DCHUBBUB_TIMEOUT_DETECTION_CTRL2;
+       uint32_t DCHUBBUB_CTRL_STATUS;
 };
 
 #define HUBBUB_REG_FIELD_LIST_DCN32(type) \
@@ -320,7 +321,12 @@ struct dcn_hubbub_registers {
                type DCHUBBUB_TIMEOUT_REQ_STALL_THRESHOLD;\
                type DCHUBBUB_TIMEOUT_PSTATE_STALL_THRESHOLD;\
                type DCHUBBUB_TIMEOUT_DETECTION_EN;\
-               type DCHUBBUB_TIMEOUT_TIMER_RESET
+               type DCHUBBUB_TIMEOUT_TIMER_RESET;\
+               type ROB_UNDERFLOW_STATUS;\
+               type ROB_OVERFLOW_STATUS;\
+               type ROB_OVERFLOW_CLEAR;\
+               type DCHUBBUB_HW_DEBUG;\
+               type CSTATE_SWATH_CHK_GOOD_MODE
 
 #define HUBBUB_STUTTER_REG_FIELD_LIST(type) \
                type DCHUBBUB_ARB_ALLOW_SR_ENTER_WATERMARK_A;\

diff --git a/drivers/gpu/drm/amd/display/dc/hubbub/dcn20/dcn20_hubbub.h b/drivers/gpu/drm/amd/display/dc/hubbub/dcn20/dcn20_hubbub.h
index 036bb3e..46d8f5c 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/hubbub/dcn20/dcn20_hubbub.h
+++ b/drivers/gpu/drm/amd/display/dc/hubbub/dcn20/dcn20_hubbub.h
@@ -96,6 +96,7 @@ struct dcn20_hubbub {
        unsigned int det1_size;
        unsigned int det2_size;
        unsigned int det3_size;
+       bool allow_sdpif_rate_limit_when_cstate_req;
 };
 
 void hubbub2_construct(struct dcn20_hubbub *hubbub,

diff --git a/drivers/gpu/drm/amd/display/dc/hubbub/dcn401/dcn401_hubbub.c b/drivers/gpu/drm/amd/display/dc/hubbub/dcn401/dcn401_hubbub.c
index 5d658e9..92fab47 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/hubbub/dcn401/dcn401_hubbub.c
+++ b/drivers/gpu/drm/amd/display/dc/hubbub/dcn401/dcn401_hubbub.c
@@ -1192,15 +1192,35 @@ static void dcn401_wait_for_det_update(struct hubbub *hubbub, int hubp_inst)
        }
 }
 
-static void dcn401_program_timeout_thresholds(struct hubbub *hubbub, struct dml2_display_arb_regs *arb_regs)
+static bool dcn401_program_arbiter(struct hubbub *hubbub, struct dml2_display_arb_regs *arb_regs, bool safe_to_lower)
 {
        struct dcn20_hubbub *hubbub2 = TO_DCN20_HUBBUB(hubbub);
 
+       bool wm_pending = false;
+       uint32_t temp;
+
        /* request backpressure and outstanding return threshold (unused)*/
        //REG_UPDATE(DCHUBBUB_TIMEOUT_DETECTION_CTRL1, DCHUBBUB_TIMEOUT_REQ_STALL_THRESHOLD, arb_regs->req_stall_threshold);
 
        /* P-State stall threshold */
        REG_UPDATE(DCHUBBUB_TIMEOUT_DETECTION_CTRL2, DCHUBBUB_TIMEOUT_PSTATE_STALL_THRESHOLD, arb_regs->pstate_stall_threshold);
+
+       if (safe_to_lower || arb_regs->allow_sdpif_rate_limit_when_cstate_req > hubbub2->allow_sdpif_rate_limit_when_cstate_req) {
+               hubbub2->allow_sdpif_rate_limit_when_cstate_req = arb_regs->allow_sdpif_rate_limit_when_cstate_req;
+
+               /* only update the required bits */
+               REG_GET(DCHUBBUB_CTRL_STATUS, DCHUBBUB_HW_DEBUG, &temp);
+               if (hubbub2->allow_sdpif_rate_limit_when_cstate_req) {
+                       temp |= (1 << 5);
+               } else {
+                       temp &= ~(1 << 5);
+               }
+               REG_UPDATE(DCHUBBUB_CTRL_STATUS, DCHUBBUB_HW_DEBUG, temp);
+       } else {
+               wm_pending = true;
+       }
+
+       return wm_pending;
 }
 
 static const struct hubbub_funcs hubbub4_01_funcs = {
@@ -1226,7 +1246,7 @@ static const struct hubbub_funcs hubbub4_01_funcs = {
        .program_det_segments = dcn401_program_det_segments,
        .program_compbuf_segments = dcn401_program_compbuf_segments,
        .wait_for_det_update = dcn401_wait_for_det_update,
-       .program_timeout_thresholds = dcn401_program_timeout_thresholds,
+       .program_arbiter = dcn401_program_arbiter,
 };
 
 void hubbub401_construct(struct dcn20_hubbub *hubbub2,

diff --git a/drivers/gpu/drm/amd/display/dc/hubbub/dcn401/dcn401_hubbub.h b/drivers/gpu/drm/amd/display/dc/hubbub/dcn401/dcn401_hubbub.h
index 5f19607..b1d9ea9 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/hubbub/dcn401/dcn401_hubbub.h
+++ b/drivers/gpu/drm/amd/display/dc/hubbub/dcn401/dcn401_hubbub.h
@@ -128,7 +128,12 @@
        HUBBUB_SF(DCHUBBUB_TIMEOUT_DETECTION_CTRL1, DCHUBBUB_TIMEOUT_REQ_STALL_THRESHOLD, mask_sh),\
        HUBBUB_SF(DCHUBBUB_TIMEOUT_DETECTION_CTRL2, DCHUBBUB_TIMEOUT_PSTATE_STALL_THRESHOLD, mask_sh),\
        HUBBUB_SF(DCHUBBUB_TIMEOUT_DETECTION_CTRL2, DCHUBBUB_TIMEOUT_DETECTION_EN, mask_sh),\
-       HUBBUB_SF(DCHUBBUB_TIMEOUT_DETECTION_CTRL2, DCHUBBUB_TIMEOUT_TIMER_RESET, mask_sh)
+       HUBBUB_SF(DCHUBBUB_TIMEOUT_DETECTION_CTRL2, DCHUBBUB_TIMEOUT_TIMER_RESET, mask_sh),\
+       HUBBUB_SF(DCHUBBUB_CTRL_STATUS, ROB_UNDERFLOW_STATUS, mask_sh),\
+       HUBBUB_SF(DCHUBBUB_CTRL_STATUS, ROB_OVERFLOW_STATUS, mask_sh),\
+       HUBBUB_SF(DCHUBBUB_CTRL_STATUS, ROB_OVERFLOW_CLEAR, mask_sh),\
+       HUBBUB_SF(DCHUBBUB_CTRL_STATUS, DCHUBBUB_HW_DEBUG, mask_sh),\
+       HUBBUB_SF(DCHUBBUB_CTRL_STATUS, CSTATE_SWATH_CHK_GOOD_MODE, mask_sh)
 
 bool hubbub401_program_urgent_watermarks(
                struct hubbub *hubbub,

diff --git a/drivers/gpu/drm/amd/display/dc/hwss/dcn401/dcn401_hwseq.c b/drivers/gpu/drm/amd/display/dc/hwss/dcn401/dcn401_hwseq.c
index e8cc1bf..5de11e2 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/hwss/dcn401/dcn401_hwseq.c
+++ b/drivers/gpu/drm/amd/display/dc/hwss/dcn401/dcn401_hwseq.c
@@ -1488,6 +1488,10 @@ void dcn401_prepare_bandwidth(struct dc *dc,
                                        &context->bw_ctx.bw.dcn.watermarks,
                                        dc->res_pool->ref_clocks.dchub_ref_clock_inKhz / 1000,
                                        false);
+       /* update timeout thresholds */
+       if (hubbub->funcs->program_arbiter) {
+               dc->wm_optimized_required |= hubbub->funcs->program_arbiter(hubbub, &context->bw_ctx.bw.dcn.arb_regs, false);
+       }
 
        /* decrease compbuf size */
        if (hubbub->funcs->program_compbuf_segments) {
@@ -1529,6 +1533,10 @@ void dcn401_optimize_bandwidth(
                                        &context->bw_ctx.bw.dcn.watermarks,
                                        dc->res_pool->ref_clocks.dchub_ref_clock_inKhz / 1000,
                                        true);
+       /* update timeout thresholds */
+       if (hubbub->funcs->program_arbiter) {
+               hubbub->funcs->program_arbiter(hubbub, &context->bw_ctx.bw.dcn.arb_regs, true);
+       }
 
        if (dc->clk_mgr->dc_mode_softmax_enabled)
                if (dc->clk_mgr->clks.dramclk_khz > dc->clk_mgr->bw_params->dc_mode_softmax_memclk * 1000 &&
@@ -1554,11 +1562,6 @@ void dcn401_optimize_bandwidth(
                                                pipe_ctx->dlg_regs.min_dst_y_next_start);
                }
        }
-
-       /* update timeout thresholds */
-       if (hubbub->funcs->program_timeout_thresholds) {
-               hubbub->funcs->program_timeout_thresholds(hubbub, &context->bw_ctx.bw.dcn.arb_regs);
-       }
 }
 
 void dcn401_fams2_global_control_lock(struct dc *dc,

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 6c1d41c..52b7456 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/inc/hw/dchubbub.h
+++ b/drivers/gpu/drm/amd/display/dc/inc/hw/dchubbub.h
@@ -228,7 +228,7 @@ struct hubbub_funcs {
        void (*program_det_segments)(struct hubbub *hubbub, int hubp_inst, unsigned det_buffer_size_seg);
        void (*program_compbuf_segments)(struct hubbub *hubbub, unsigned compbuf_size_seg, bool safe_to_increase);
        void (*wait_for_det_update)(struct hubbub *hubbub, int hubp_inst);
-       void (*program_timeout_thresholds)(struct hubbub *hubbub, struct dml2_display_arb_regs *arb_regs);
+       bool (*program_arbiter)(struct hubbub *hubbub, struct dml2_display_arb_regs *arb_regs, bool safe_to_lower);
 };
 
 struct hubbub {

diff --git a/drivers/gpu/drm/amd/display/dc/resource/dcn401/dcn401_resource.h b/drivers/gpu/drm/amd/display/dc/resource/dcn401/dcn401_resource.h
index 7c8d61d..19568c3 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/resource/dcn401/dcn401_resource.h
+++ b/drivers/gpu/drm/amd/display/dc/resource/dcn401/dcn401_resource.h
@@ -612,7 +612,8 @@ void dcn401_prepare_mcache_programming(struct dc *dc, struct dc_state *context);
        SR(DCHUBBUB_SDPIF_CFG1),                                                 \
        SR(DCHUBBUB_MEM_PWR_MODE_CTRL),                                          \
        SR(DCHUBBUB_TIMEOUT_DETECTION_CTRL1),                                    \
-       SR(DCHUBBUB_TIMEOUT_DETECTION_CTRL2)
+       SR(DCHUBBUB_TIMEOUT_DETECTION_CTRL2),                                                                    \
+       SR(DCHUBBUB_CTRL_STATUS)
 
 /* DCCG */