Re: [PATCH v1 1/2] drm/msm/dp: Add support for SC7280 eDP

Quoting Sankeerth Billakanti (2021-08-11 17:08:01)

diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_catalog.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_catalog.c index b131fd37..1096c44 100644 --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_catalog.c +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_catalog.c @@ -856,9 +856,9 @@ static const struct dpu_intf_cfg sm8150_intf[] = { };

static const struct dpu_intf_cfg sc7280_intf[] = {

•   INTF_BLK("intf_0", INTF_0, 0x34000, INTF_DP, 0, 24, INTF_SC7280_MASK, MDP_SSPP_TOP0_INTR, 24, 25),
  

•   INTF_BLK("intf_0", INTF_0, 0x34000, INTF_DP, 1, 24, INTF_SC7280_MASK, MDP_SSPP_TOP0_INTR, 24, 25),
    INTF_BLK("intf_1", INTF_1, 0x35000, INTF_DSI, 0, 24, INTF_SC7280_MASK, MDP_SSPP_TOP0_INTR, 26, 27),
  

•   INTF_BLK("intf_5", INTF_5, 0x39000, INTF_EDP, 0, 24, INTF_SC7280_MASK, MDP_SSPP_TOP0_INTR, 22, 23),
  

•   INTF_BLK("intf_5", INTF_5, 0x39000, INTF_DP, 0, 24, INTF_SC7280_MASK, MDP_SSPP_TOP0_INTR, 22, 23),
  

};

/************************************************************* diff --git a/drivers/gpu/drm/msm/dp/dp_ctrl.c b/drivers/gpu/drm/msm/dp/dp_ctrl.c index d2569da..06d5a2d 100644 --- a/drivers/gpu/drm/msm/dp/dp_ctrl.c +++ b/drivers/gpu/drm/msm/dp/dp_ctrl.c @@ -1244,7 +1244,9 @@ static int dp_ctrl_link_train(struct dp_ctrl_private *ctrl, struct dp_cr_status *cr, int *training_step) { int ret = 0;

•   u8 *dpcd = ctrl->panel->dpcd;
    u8 encoding = DP_SET_ANSI_8B10B;
  

•   u8 ssc = 0, assr = 0;
  

Please don't initialize to zero and then overwrite it before using it. It hides usage before actual initialization bugs.

    struct dp_link_info link_info = {0};

    dp_ctrl_config_ctrl(ctrl);

@@ -1254,9 +1256,21 @@ static int dp_ctrl_link_train(struct dp_ctrl_private *ctrl, link_info.capabilities = DP_LINK_CAP_ENHANCED_FRAMING;

    dp_aux_link_configure(ctrl->aux, &link_info);

•   if (dpcd[DP_MAX_DOWNSPREAD] & DP_MAX_DOWNSPREAD_0_5) {
  

•           ssc = DP_SPREAD_AMP_0_5;
  

•           drm_dp_dpcd_write(ctrl->aux, DP_DOWNSPREAD_CTRL, &ssc, 1);
  

•   }
  

•   drm_dp_dpcd_write(ctrl->aux, DP_MAIN_LINK_CHANNEL_CODING_SET,
                            &encoding, 1);
  
  

•   if (dpcd[DP_EDP_CONFIGURATION_CAP] & DP_ALTERNATE_SCRAMBLER_RESET_CAP) {
  

•           assr = DP_ALTERNATE_SCRAMBLER_RESET_ENABLE;
  

•           drm_dp_dpcd_write(ctrl->aux, DP_EDP_CONFIGURATION_SET,
  

•                           &assr, 1);
  

•   }
  

•   ret = dp_ctrl_link_train_1(ctrl, cr, training_step);
    if (ret) {
            DRM_ERROR("link training #1 failed. ret=%d\n", ret);
  

@@ -1328,9 +1342,11 @@ static int dp_ctrl_enable_mainlink_clocks(struct dp_ctrl_private *ctrl) struct dp_io *dp_io = &ctrl->parser->io; struct phy *phy = dp_io->phy; struct phy_configure_opts_dp *opts_dp = &dp_io->phy_opts.dp;

•   u8 *dpcd = ctrl->panel->dpcd;
  

const?

    opts_dp->lanes = ctrl->link->link_params.num_lanes;
    opts_dp->link_rate = ctrl->link->link_params.rate / 100;

•   opts_dp->ssc = dpcd[DP_MAX_DOWNSPREAD] & DP_MAX_DOWNSPREAD_0_5;
    dp_ctrl_set_clock_rate(ctrl, DP_CTRL_PM, "ctrl_link",
                                    ctrl->link->link_params.rate * 1000);
  
  

@@ -1760,6 +1776,9 @@ int dp_ctrl_on_stream(struct dp_ctrl *dp_ctrl) ctrl->link->link_params.num_lanes = ctrl->panel->link_info.num_lanes; ctrl->dp_ctrl.pixel_rate = ctrl->panel->dp_mode.drm_mode.clock;

•   if (ctrl->dp_ctrl.pixel_rate == 0)
  

•           return -EINVAL;
  

Why are we enabling the stream with a zero pixel clk?

    DRM_DEBUG_DP("rate=%d, num_lanes=%d, pixel_rate=%d\n",
            ctrl->link->link_params.rate,
            ctrl->link->link_params.num_lanes, ctrl->dp_ctrl.pixel_rate);

diff --git a/drivers/gpu/drm/msm/dp/dp_display.c b/drivers/gpu/drm/msm/dp/dp_display.c index ee5bf64..a772290 100644 --- a/drivers/gpu/drm/msm/dp/dp_display.c +++ b/drivers/gpu/drm/msm/dp/dp_display.c @@ -117,8 +117,36 @@ struct dp_display_private { struct dp_audio *audio; };

+struct msm_dp_config {

•   phys_addr_t io_start[3];
  

•   size_t num_dp;
  

+};

+static const struct msm_dp_config sc7180_dp_cfg = {

•   .io_start = { 0x0ae90000 },
  

•   .num_dp = 1,
  

+};

+static const struct msm_dp_config sc8180x_dp_cfg = {

•   .io_start = { 0xae90000, 0xae98000, 0 },
  

•   .num_dp = 3,
  

+};

+static const struct msm_dp_config sc8180x_edp_cfg = {

•   .io_start = { 0, 0, 0xae9a000 },
  

•   .num_dp = 3,
  

+};

+static const struct msm_dp_config sc7280_edp_cfg = {

•   .io_start = { 0xaea0000, 0 },
  

•   .num_dp = 2,
  

+};

Are all of these supposed to be here?

static const struct of_device_id dp_dt_match[] = {

•   {.compatible = "qcom,sc7180-dp"},
  

•   { .compatible = "qcom,sc7180-dp", .data = &sc7180_dp_cfg },
  

•   { .compatible = "qcom,sc8180x-dp", .data = &sc8180x_dp_cfg },
  

•   { .compatible = "qcom,sc8180x-edp", .data = &sc8180x_edp_cfg },
  

•   { .compatible = "qcom,sc7280-edp", .data = &sc7280_edp_cfg },
  

Please sort alphabetically on compatible string, it helps avoid conflicts in the future.

    {}

};

@@ -1408,7 +1436,7 @@ void msm_dp_irq_postinstall(struct msm_dp *dp_display)

    dp_hpd_event_setup(dp);

•   dp_add_event(dp, EV_HPD_INIT_SETUP, 0, 100);
  

•   dp_add_event(dp, EV_HPD_INIT_SETUP, 0, 1);
  

}

void msm_dp_debugfs_init(struct msm_dp *dp_display, struct drm_minor *minor) diff --git a/drivers/gpu/drm/msm/dp/dp_parser.c b/drivers/gpu/drm/msm/dp/dp_parser.c index 0519dd3..c05fc0a 100644 --- a/drivers/gpu/drm/msm/dp/dp_parser.c +++ b/drivers/gpu/drm/msm/dp/dp_parser.c @@ -248,6 +248,33 @@ static int dp_parser_clock(struct dp_parser *parser) return 0; }

+static int dp_parser_gpio(struct dp_parser *parser) +{

•   struct device *dev = &parser->pdev->dev;
  

•   int ret;
  

•   parser->panel_bklt_gpio = devm_gpiod_get(dev, "panel-bklt",
  

•                   GPIOD_OUT_HIGH);
  

•   if (IS_ERR(parser->panel_bklt_gpio)) {
  

•           ret = PTR_ERR(parser->panel_bklt_gpio);
  

•           parser->panel_bklt_gpio = NULL;
  

•           DRM_ERROR("%s: cannot get panel-bklt gpio, %d\n", __func__, ret);
  

•           goto fail;
  

•   }
  

•   parser->panel_pwm_gpio = devm_gpiod_get(dev, "panel-pwm", GPIOD_OUT_HIGH);
  

•   if (IS_ERR(parser->panel_pwm_gpio)) {
  

•           ret = PTR_ERR(parser->panel_pwm_gpio);
  

•           parser->panel_pwm_gpio = NULL;
  

•           DRM_ERROR("%s: cannot get panel-pwm gpio, %d\n", __func__, ret);
  

•           goto fail;
  

•   }
  

•   DRM_INFO("gpio on");
  

+fail:

•   return 0;
  

+}

Don't we have pwm backlight drivers like drivers/video/backlight/pwm_bl.c to support this? This sort of thing doesn't belong in the dp driver.

static int dp_parser_parse(struct dp_parser *parser) { int rc = 0; @@ -269,6 +296,10 @@ static int dp_parser_parse(struct dp_parser *parser) if (rc) return rc;

•   rc = dp_parser_gpio(parser);
  

•   if (rc)
  

•           return rc;
  

•   /* Map the corresponding regulator information according to
     * version. Currently, since we only have one supported platform,
     * mapping the regulator directly.