[PATCH 14/18] drm/amd/display: Fix crash when setting ABM pipe/backlight

[Aurabindo Pillai]

From: Leon Huang <leon.huang1 at amd.com>

[Why] Setting ABM pipe/backlight crashes the system when abm callback
func pointers are NULL For some usecase, driver would like to control
PWM level before ABM resource is ready. But recent flow refactor of ABM
didn't consider that use case.

[How] Rollback flow that sending inbox command to dmub directly when ABM
function pointers aren't ready.

Acked-by: Aurabindo Pillai <aurabindo.pillai at amd.com>
Signed-off-by: Leon Huang <Leon.Huang1 at amd.com>
Reviewed-by: Chun-Liang Chang <chun-liang.chang at amd.com>
---
 .../drm/amd/display/dc/dcn21/dcn21_hwseq.c    | 81 ++++++++++++++++---
 1 file changed, 69 insertions(+), 12 deletions(-)

diff --git a/drivers/gpu/drm/amd/display/dc/dcn21/dcn21_hwseq.c b/drivers/gpu/drm/amd/display/dc/dcn21/dcn21_hwseq.c
index 69b2f277d41e..5d77f7586816 100644
--- a/drivers/gpu/drm/amd/display/dc/dcn21/dcn21_hwseq.c
+++ b/drivers/gpu/drm/amd/display/dc/dcn21/dcn21_hwseq.c
@@ -137,6 +137,47 @@ void dcn21_PLAT_58856_wa(struct dc_state *context, struct pipe_ctx *pipe_ctx)
 	pipe_ctx->stream->dpms_off = true;
 }
 
+static bool dmub_abm_set_pipe(struct abm *abm, uint32_t otg_inst, uint32_t option, uint32_t panel_inst)
+{
+	union dmub_rb_cmd cmd;
+	struct dc_context *dc = abm->ctx;
+	uint32_t ramping_boundary = 0xFFFF;
+
+	memset(&cmd, 0, sizeof(cmd));
+	cmd.abm_set_pipe.header.type = DMUB_CMD__ABM;
+	cmd.abm_set_pipe.header.sub_type = DMUB_CMD__ABM_SET_PIPE;
+	cmd.abm_set_pipe.abm_set_pipe_data.otg_inst = otg_inst;
+	cmd.abm_set_pipe.abm_set_pipe_data.set_pipe_option = option;
+	cmd.abm_set_pipe.abm_set_pipe_data.panel_inst = panel_inst;
+	cmd.abm_set_pipe.abm_set_pipe_data.ramping_boundary = ramping_boundary;
+	cmd.abm_set_pipe.header.payload_bytes = sizeof(struct dmub_cmd_abm_set_pipe_data);
+
+	dc_dmub_srv_cmd_queue(dc->dmub_srv, &cmd);
+	dc_dmub_srv_cmd_execute(dc->dmub_srv);
+	dc_dmub_srv_wait_idle(dc->dmub_srv);
+
+	return true;
+}
+
+static void dmub_abm_set_backlight(struct dc_context *dc, uint32_t backlight_pwm_u16_16,
+									uint32_t frame_ramp, uint32_t panel_inst)
+{
+	union dmub_rb_cmd cmd;
+
+	memset(&cmd, 0, sizeof(cmd));
+	cmd.abm_set_backlight.header.type = DMUB_CMD__ABM;
+	cmd.abm_set_backlight.header.sub_type = DMUB_CMD__ABM_SET_BACKLIGHT;
+	cmd.abm_set_backlight.abm_set_backlight_data.frame_ramp = frame_ramp;
+	cmd.abm_set_backlight.abm_set_backlight_data.backlight_user_level = backlight_pwm_u16_16;
+	cmd.abm_set_backlight.abm_set_backlight_data.version = DMUB_CMD_ABM_CONTROL_VERSION_1;
+	cmd.abm_set_backlight.abm_set_backlight_data.panel_mask = (0x01 << panel_inst);
+	cmd.abm_set_backlight.header.payload_bytes = sizeof(struct dmub_cmd_abm_set_backlight_data);
+
+	dc_dmub_srv_cmd_queue(dc->dmub_srv, &cmd);
+	dc_dmub_srv_cmd_execute(dc->dmub_srv);
+	dc_dmub_srv_wait_idle(dc->dmub_srv);
+}
+
 void dcn21_set_abm_immediate_disable(struct pipe_ctx *pipe_ctx)
 {
 	struct abm *abm = pipe_ctx->stream_res.abm;
@@ -150,9 +191,13 @@ void dcn21_set_abm_immediate_disable(struct pipe_ctx *pipe_ctx)
 		return;
 	}
 
-	if (abm && panel_cntl && abm->funcs->set_pipe_ex) {
-		abm->funcs->set_pipe_ex(abm, otg_inst, SET_ABM_PIPE_IMMEDIATELY_DISABLE,
+	if (abm && panel_cntl) {
+		if (abm->funcs && abm->funcs->set_pipe_ex)
+			abm->funcs->set_pipe_ex(abm, otg_inst, SET_ABM_PIPE_IMMEDIATELY_DISABLE,
 			panel_cntl->inst);
+		else {
+				dmub_abm_set_pipe(abm, otg_inst, SET_ABM_PIPE_IMMEDIATELY_DISABLE, panel_cntl->inst);
+		}
 		panel_cntl->funcs->store_backlight_level(panel_cntl);
 	}
 }
@@ -169,9 +214,13 @@ void dcn21_set_pipe(struct pipe_ctx *pipe_ctx)
 		return;
 	}
 
-	if (abm && panel_cntl && abm->funcs->set_pipe_ex)
-		abm->funcs->set_pipe_ex(abm, otg_inst, SET_ABM_PIPE_NORMAL, panel_cntl->inst);
-
+	if (abm && panel_cntl) {
+		if (abm->funcs && abm->funcs->set_pipe_ex)
+			abm->funcs->set_pipe_ex(abm, otg_inst, SET_ABM_PIPE_NORMAL, panel_cntl->inst);
+		else {
+				dmub_abm_set_pipe(abm, otg_inst, SET_ABM_PIPE_NORMAL, panel_cntl->inst);
+		}
+	}
 }
 
 bool dcn21_set_backlight_level(struct pipe_ctx *pipe_ctx,
@@ -180,23 +229,31 @@ bool dcn21_set_backlight_level(struct pipe_ctx *pipe_ctx,
 {
 	struct dc_context *dc = pipe_ctx->stream->ctx;
 	struct panel_cntl *panel_cntl = pipe_ctx->stream->link->panel_cntl;
+	struct abm *abm = pipe_ctx->stream_res.abm;
 
 	if (dc->dc->res_pool->dmcu) {
 		dce110_set_backlight_level(pipe_ctx, backlight_pwm_u16_16, frame_ramp);
 		return true;
 	}
 
-	if (pipe_ctx->stream_res.abm != NULL) {
-		struct abm *abm = pipe_ctx->stream_res.abm;
+	if (abm != NULL) {
+
 		uint32_t otg_inst = pipe_ctx->stream_res.tg->inst;
 
-		if (abm && panel_cntl && abm->funcs->set_pipe_ex)
-			abm->funcs->set_pipe_ex(abm, otg_inst, SET_ABM_PIPE_NORMAL, panel_cntl->inst);
+		if (abm && panel_cntl) {
+			if (abm->funcs && abm->funcs->set_pipe_ex)
+				abm->funcs->set_pipe_ex(abm, otg_inst, SET_ABM_PIPE_NORMAL, panel_cntl->inst);
+			else {
+					dmub_abm_set_pipe(abm, otg_inst, SET_ABM_PIPE_NORMAL, panel_cntl->inst);
+			}
+		}
+	}
 
-		if (panel_cntl && abm->funcs->set_backlight_level_pwm)
-			abm->funcs->set_backlight_level_pwm(abm, backlight_pwm_u16_16,
+	if (abm && abm->funcs && abm->funcs->set_backlight_level_pwm)
+		abm->funcs->set_backlight_level_pwm(abm, backlight_pwm_u16_16,
 			frame_ramp, 0, panel_cntl->inst);
-	}
+	else
+		dmub_abm_set_backlight(dc, backlight_pwm_u16_16, frame_ramp, panel_cntl->inst);
 
 	return true;
 }
-- 
2.39.0