drm/nouveau/dp: enable down-spread if vbios and sink support it

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

2 files changed, 20 insertions, 29 deletions

diff --git a/drivers/gpu/drm/nouveau/nouveau_dp.c b/drivers/gpu/drm/nouveau/nouveau_dp.c
index 3777616cc157..89d5c161c8bd 100644
--- a/drivers/gpu/drm/nouveau/nouveau_dp.c
+++ b/drivers/gpu/drm/nouveau/nouveau_dp.c
@@ -160,25 +160,6 @@ out:
         return ret;
 }
 
-static int
-auxch_rd(struct drm_encoder *encoder, int address, uint8_t *buf, int size)
-{
-        struct drm_device *dev = encoder->dev;
-        struct nouveau_encoder *nv_encoder = nouveau_encoder(encoder);
-        struct nouveau_i2c_chan *auxch;
-        int ret;
-
-        auxch = nouveau_i2c_find(dev, nv_encoder->dcb->i2c_index);
-        if (!auxch)
-                return -ENODEV;
-
-        ret = nouveau_dp_auxch(auxch, 9, address, buf, size);
-        if (ret)
-                return ret;
-
-        return 0;
-}
-
 static u32
 dp_link_bw_get(struct drm_device *dev, int or, int link)
 {
@@ -298,7 +279,7 @@ struct dp_state {
         int crtc;
         int or;
         int link;
-        int enh_frame;
+        u8 *dpcd;
         int link_nr;
         u32 link_bw;
         u8  stat[6];
@@ -343,7 +324,7 @@ dp_set_link_config(struct drm_device *dev, struct dp_state *dp)
         /* configure lane count on the source */
         dp_ctrl = ((1 << dp->link_nr) - 1) << 16;
         sink[1] = dp->link_nr;
-        if (dp->enh_frame) {
+        if (dp->dpcd[2] & DP_ENHANCED_FRAME_CAP) {
                 dp_ctrl |= 0x00004000;
                 sink[1] |= DP_LANE_COUNT_ENHANCED_FRAME_EN;
         }
@@ -505,7 +486,6 @@ nouveau_dp_link_train(struct drm_encoder *encoder, u32 datarate)
         const u32 *link_bw = bw_list;
         struct dp_state dp;
         u8 *bios, headerlen;
-        u16 script;
 
         auxch = nouveau_i2c_find(dev, nv_encoder->dcb->i2c_index);
         if (!auxch)
@@ -520,7 +500,7 @@ nouveau_dp_link_train(struct drm_encoder *encoder, u32 datarate)
         dp.auxch = auxch->rd;
         dp.or = nv_encoder->or;
         dp.link = !(nv_encoder->dcb->sorconf.link & 1);
-        dp.enh_frame = nv_encoder->dp.enhanced_frame;
+        dp.dpcd = nv_encoder->dp.dpcd;
 
         /* some sinks toggle hotplug in response to some of the actions
          * we take during link training (DP_SET_POWER is one), we need
@@ -528,6 +508,15 @@ nouveau_dp_link_train(struct drm_encoder *encoder, u32 datarate)
          */
         pgpio->irq_enable(dev, nv_connector->dcb->gpio_tag, false);
 
+        /* enable down-spreading, if possible */
+        if (headerlen >= 16) {
+                u16 script = ROM16(bios[14]);
+                if (nv_encoder->dp.dpcd[3] & 1)
+                        script = ROM16(bios[12]);
+
+                nouveau_bios_run_init_table(dev, script, dp.dcb, dp.crtc);
+        }
+
         /* execute pre-train script from vbios */
         nouveau_bios_run_init_table(dev, ROM16(bios[6]), dp.dcb, dp.crtc);
 
@@ -575,17 +564,20 @@ nouveau_dp_detect(struct drm_encoder *encoder)
 {
         struct nouveau_encoder *nv_encoder = nouveau_encoder(encoder);
         struct drm_device *dev = encoder->dev;
-        uint8_t dpcd[4];
+        struct nouveau_i2c_chan *auxch;
+        u8 *dpcd = nv_encoder->dp.dpcd;
         int ret;
 
-        ret = auxch_rd(encoder, 0x0000, dpcd, 4);
+        auxch = nouveau_i2c_find(dev, nv_encoder->dcb->i2c_index);
+        if (!auxch)
+                return false;
+
+        ret = auxch_tx(dev, auxch->rd, 9, DP_DPCD_REV, dpcd, 8);
         if (ret)
                 return false;
 
-        nv_encoder->dp.dpcd_version = dpcd[0];
         nv_encoder->dp.link_bw = 27000 * dpcd[1];
         nv_encoder->dp.link_nr = dpcd[2] & DP_MAX_LANE_COUNT_MASK;
-        nv_encoder->dp.enhanced_frame = dpcd[2] & DP_ENHANCED_FRAME_CAP;
 
         NV_DEBUG_KMS(dev, "display: %dx%d dpcd 0x%02x\n",
                      nv_encoder->dp.link_nr, nv_encoder->dp.link_bw, dpcd[0]);
diff --git a/drivers/gpu/drm/nouveau/nouveau_encoder.h b/drivers/gpu/drm/nouveau/nouveau_encoder.h
index deafe7b1f524..e5d6e3faff3d 100644
--- a/drivers/gpu/drm/nouveau/nouveau_encoder.h
+++ b/drivers/gpu/drm/nouveau/nouveau_encoder.h
@@ -49,10 +49,9 @@ struct nouveau_encoder {
 
         union {
                 struct {
-                        int dpcd_version;
+                        u8  dpcd[8];
                         int link_nr;
                         int link_bw;
-                        bool enhanced_frame;
                         u32 datarate;
                 } dp;
         };