drm/bridge: cdns: Separate DSI and D-PHY configuration

The current configuration of the DSI bridge and its associated D-PHY is
intertwined. In order to ease the future conversion to the phy framework
for the D-PHY part, let's split the configuration in two.

Reviewed-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
Link: https://patchwork.freedesktop.org/patch/msgid/0b3bea44e05745b65c23af7926ca546bc80a1bcc.1548085432.git-series.maxime.ripard@bootlin.com

1 files changed, 73 insertions, 28 deletions

diff --git a/drivers/gpu/drm/bridge/cdns-dsi.c b/drivers/gpu/drm/bridge/cdns-dsi.c
index 924abe82ea3c..0f5bb3dca828 100644
--- a/drivers/gpu/drm/bridge/cdns-dsi.c
+++ b/drivers/gpu/drm/bridge/cdns-dsi.c
@@ -547,6 +547,15 @@ bridge_to_cdns_dsi_input(struct drm_bridge *bridge)
         return container_of(bridge, struct cdns_dsi_input, bridge);
 }
 
+static unsigned int mode_to_dpi_hfp(const struct drm_display_mode *mode,
+                                    bool mode_valid_check)
+{
+        if (mode_valid_check)
+                return mode->hsync_start - mode->hdisplay;
+
+        return mode->crtc_hsync_start - mode->crtc_hdisplay;
+}
+
 static int cdns_dsi_get_dphy_pll_cfg(struct cdns_dphy *dphy,
                                      struct cdns_dphy_cfg *cfg,
                                      unsigned int dpi_htotal,
@@ -733,14 +742,12 @@ static unsigned int dpi_to_dsi_timing(unsigned int dpi_timing,
 static int cdns_dsi_mode2cfg(struct cdns_dsi *dsi,
                              const struct drm_display_mode *mode,
                              struct cdns_dsi_cfg *dsi_cfg,
-                             struct cdns_dphy_cfg *dphy_cfg,
                              bool mode_valid_check)
 {
-        unsigned long dsi_htotal = 0, dsi_hss_hsa_hse_hbp = 0;
         struct cdns_dsi_output *output = &dsi->output;
-        unsigned int dsi_hfp_ext = 0, dpi_hfp, tmp;
+        unsigned int tmp;
         bool sync_pulse = false;
-        int bpp, nlanes, ret;
+        int bpp, nlanes;
 
         memset(dsi_cfg, 0, sizeof(*dsi_cfg));
 
@@ -759,8 +766,6 @@ static int cdns_dsi_mode2cfg(struct cdns_dsi *dsi,
                        mode->crtc_hsync_end : mode->crtc_hsync_start);
 
         dsi_cfg->hbp = dpi_to_dsi_timing(tmp, bpp, DSI_HBP_FRAME_OVERHEAD);
-        dsi_htotal += dsi_cfg->hbp + DSI_HBP_FRAME_OVERHEAD;
-        dsi_hss_hsa_hse_hbp += dsi_cfg->hbp + DSI_HBP_FRAME_OVERHEAD;
 
         if (sync_pulse) {
                 if (mode_valid_check)
@@ -770,49 +775,91 @@ static int cdns_dsi_mode2cfg(struct cdns_dsi *dsi,
 
                 dsi_cfg->hsa = dpi_to_dsi_timing(tmp, bpp,
                                                  DSI_HSA_FRAME_OVERHEAD);
-                dsi_htotal += dsi_cfg->hsa + DSI_HSA_FRAME_OVERHEAD;
-                dsi_hss_hsa_hse_hbp += dsi_cfg->hsa + DSI_HSA_FRAME_OVERHEAD;
         }
 
         dsi_cfg->hact = dpi_to_dsi_timing(mode_valid_check ?
                                           mode->hdisplay : mode->crtc_hdisplay,
                                           bpp, 0);
-        dsi_htotal += dsi_cfg->hact;
+        dsi_cfg->hfp = dpi_to_dsi_timing(mode_to_dpi_hfp(mode, mode_valid_check),
+                                         bpp, DSI_HFP_FRAME_OVERHEAD);
 
-        if (mode_valid_check)
-                dpi_hfp = mode->hsync_start - mode->hdisplay;
-        else
-                dpi_hfp = mode->crtc_hsync_start - mode->crtc_hdisplay;
+        return 0;
+}
+
+static int cdns_dphy_validate(struct cdns_dsi *dsi,
+                              struct cdns_dsi_cfg *dsi_cfg,
+                              struct cdns_dphy_cfg *dphy_cfg,
+                              const struct drm_display_mode *mode,
+                              bool mode_valid_check)
+{
+        struct cdns_dsi_output *output = &dsi->output;
+        unsigned long dsi_htotal;
+        unsigned int dsi_hfp_ext = 0;
+
+        int ret;
+
+        dsi_htotal = dsi_cfg->hbp + DSI_HBP_FRAME_OVERHEAD;
+        if (output->dev->mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE)
+                dsi_htotal += dsi_cfg->hsa + DSI_HSA_FRAME_OVERHEAD;
 
-        dsi_cfg->hfp = dpi_to_dsi_timing(dpi_hfp, bpp, DSI_HFP_FRAME_OVERHEAD);
+        dsi_htotal += dsi_cfg->hact;
         dsi_htotal += dsi_cfg->hfp + DSI_HFP_FRAME_OVERHEAD;
 
         if (mode_valid_check)
                 ret = cdns_dsi_get_dphy_pll_cfg(dsi->dphy, dphy_cfg,
-                                                mode->htotal, bpp,
+                                                mode->htotal,
+                                                mipi_dsi_pixel_format_to_bpp(output->dev->format),
                                                 mode->clock * 1000,
-                                                dsi_htotal, nlanes,
+                                                dsi_htotal,
+                                                output->dev->lanes,
                                                 &dsi_hfp_ext);
         else
                 ret = cdns_dsi_get_dphy_pll_cfg(dsi->dphy, dphy_cfg,
-                                                mode->crtc_htotal, bpp,
+                                                mode->crtc_htotal,
+                                                mipi_dsi_pixel_format_to_bpp(output->dev->format),
                                                 mode->crtc_clock * 1000,
-                                                dsi_htotal, nlanes,
+                                                dsi_htotal,
+                                                output->dev->lanes,
                                                 &dsi_hfp_ext);
-
         if (ret)
                 return ret;
 
         dsi_cfg->hfp += dsi_hfp_ext;
-        dsi_htotal += dsi_hfp_ext;
-        dsi_cfg->htotal = dsi_htotal;
+        dsi_cfg->htotal = dsi_htotal + dsi_hfp_ext;
+
+        return 0;
+}
+
+static int cdns_dsi_check_conf(struct cdns_dsi *dsi,
+                               const struct drm_display_mode *mode,
+                               struct cdns_dsi_cfg *dsi_cfg,
+                               struct cdns_dphy_cfg *dphy_cfg,
+                               bool mode_valid_check)
+{
+        struct cdns_dsi_output *output = &dsi->output;
+        unsigned long dsi_hss_hsa_hse_hbp;
+        unsigned int nlanes = output->dev->lanes;
+        int ret;
+
+        ret = cdns_dsi_mode2cfg(dsi, mode, dsi_cfg, mode_valid_check);
+        if (ret)
+                return ret;
+
+        ret = cdns_dphy_validate(dsi, dsi_cfg, dphy_cfg, mode, mode_valid_check);
+        if (ret)
+                return ret;
+
+        dsi_hss_hsa_hse_hbp = dsi_cfg->hbp + DSI_HBP_FRAME_OVERHEAD;
+        if (output->dev->mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE)
+                dsi_hss_hsa_hse_hbp += dsi_cfg->hsa + DSI_HSA_FRAME_OVERHEAD;
 
         /*
          * Make sure DPI(HFP) > DSI(HSS+HSA+HSE+HBP) to guarantee that the FIFO
          * is empty before we start a receiving a new line on the DPI
          * interface.
          */
-        if ((u64)dphy_cfg->lane_bps * dpi_hfp * nlanes <
+        if ((u64)dphy_cfg->lane_bps *
+            mode_to_dpi_hfp(mode, mode_valid_check) * nlanes <
             (u64)dsi_hss_hsa_hse_hbp *
             (mode_valid_check ? mode->clock : mode->crtc_clock) * 1000)
                 return -EINVAL;
@@ -844,7 +891,7 @@ cdns_dsi_bridge_mode_valid(struct drm_bridge *bridge,
         struct cdns_dsi_output *output = &dsi->output;
         struct cdns_dphy_cfg dphy_cfg;
         struct cdns_dsi_cfg dsi_cfg;
-        int bpp, nlanes, ret;
+        int bpp, ret;
 
         /*
          * VFP_DSI should be less than VFP_DPI and VFP_DSI should be at
@@ -862,11 +909,9 @@ cdns_dsi_bridge_mode_valid(struct drm_bridge *bridge,
         if ((mode->hdisplay * bpp) % 32)
                 return MODE_H_ILLEGAL;
 
-        nlanes = output->dev->lanes;
-
-        ret = cdns_dsi_mode2cfg(dsi, mode, &dsi_cfg, &dphy_cfg, true);
+        ret = cdns_dsi_check_conf(dsi, mode, &dsi_cfg, &dphy_cfg, true);
         if (ret)
-                return MODE_CLOCK_RANGE;
+                return MODE_BAD;
 
         return MODE_OK;
 }
@@ -992,7 +1037,7 @@ static void cdns_dsi_bridge_enable(struct drm_bridge *bridge)
         bpp = mipi_dsi_pixel_format_to_bpp(output->dev->format);
         nlanes = output->dev->lanes;
 
-        WARN_ON_ONCE(cdns_dsi_mode2cfg(dsi, mode, &dsi_cfg, &dphy_cfg, false));
+        WARN_ON_ONCE(cdns_dsi_check_conf(dsi, mode, &dsi_cfg, &dphy_cfg, false));
 
         cdns_dsi_hs_init(dsi, &dphy_cfg);
         cdns_dsi_init_link(dsi);