drm/nouveau/disp: add output method to fetch edid

- needed to support TMDS EDID on RM

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Acked-by: Danilo Krummrich <me@dakr.org>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230919220442.202488-9-lyude@redhat.com

drivers/gpu/drm/nouveau/include/nvif/if0012.h

@@ -13,6 +13,7 @@ union nvif_outp_args {
 };
 
 #define NVIF_OUTP_V0_DETECT        0x00
+#define NVIF_OUTP_V0_EDID_GET      0x01
 
 #define NVIF_OUTP_V0_ACQUIRE       0x11
 #define NVIF_OUTP_V0_RELEASE       0x12
@@ -36,6 +37,15 @@ union nvif_outp_detect_args {
 	} v0;
 };
 
+union nvif_outp_edid_get_args {
+	struct nvif_outp_edid_get_v0 {
+		__u8  version;
+		__u8  pad01;
+		__u16 size;
+		__u8  data[2048];
+	} v0;
+};
+
 union nvif_outp_load_detect_args {
 	struct nvif_outp_load_detect_v0 {
 		__u8  version;

drivers/gpu/drm/nouveau/include/nvif/outp.h

@@ -25,6 +25,7 @@ enum nvif_outp_detect_status {
 };
 
 enum nvif_outp_detect_status nvif_outp_detect(struct nvif_outp *);
+int nvif_outp_edid_get(struct nvif_outp *, u8 **pedid);
 
 int nvif_outp_load_detect(struct nvif_outp *, u32 loadval);
 int nvif_outp_acquire_rgb_crt(struct nvif_outp *);

drivers/gpu/drm/nouveau/nouveau_connector.c

@@ -570,7 +570,6 @@ nouveau_connector_detect(struct drm_connector *connector, bool force)
 	struct nouveau_connector *nv_connector = nouveau_connector(connector);
 	struct nouveau_encoder *nv_encoder = NULL;
 	struct nouveau_encoder *nv_partner;
-	struct i2c_adapter *i2c;
 	int type;
 	int ret;
 	enum drm_connector_status conn_status = connector_status_disconnected;
@@ -593,15 +592,20 @@ nouveau_connector_detect(struct drm_connector *connector, bool force)
 	}
 
 	nv_encoder = nouveau_connector_ddc_detect(connector);
-	if (nv_encoder && (i2c = nv_encoder->i2c) != NULL) {
+	if (nv_encoder) {
-		struct edid *new_edid;
+		struct edid *new_edid = NULL;
 
-		if ((vga_switcheroo_handler_flags() &
+		if (nv_encoder->i2c) {
-		     VGA_SWITCHEROO_CAN_SWITCH_DDC) &&
+			if ((vga_switcheroo_handler_flags() & VGA_SWITCHEROO_CAN_SWITCH_DDC) &&
-		    nv_connector->type == DCB_CONNECTOR_LVDS)
+			    nv_connector->type == DCB_CONNECTOR_LVDS)
-			new_edid = drm_get_edid_switcheroo(connector, i2c);
+				new_edid = drm_get_edid_switcheroo(connector, nv_encoder->i2c);
-		else
+			else
-			new_edid = drm_get_edid(connector, i2c);
+				new_edid = drm_get_edid(connector, nv_encoder->i2c);
+		} else {
+			ret = nvif_outp_edid_get(&nv_encoder->outp, (u8 **)&new_edid);
+			if (ret < 0)
+				return connector_status_disconnected;
+		}
 
 		nouveau_connector_set_edid(nv_connector, new_edid);
 		if (!nv_connector->edid) {

drivers/gpu/drm/nouveau/nvif/outp.c

@@ -210,6 +210,36 @@ nvif_outp_load_detect(struct nvif_outp *outp, u32 loadval)
 	return ret < 0 ? ret : args.load;
 }
 
+int
+nvif_outp_edid_get(struct nvif_outp *outp, u8 **pedid)
+{
+	struct nvif_outp_edid_get_v0 *args;
+	int ret;
+
+	args = kmalloc(sizeof(*args), GFP_KERNEL);
+	if (!args)
+		return -ENOMEM;
+
+	args->version = 0;
+
+	ret = nvif_mthd(&outp->object, NVIF_OUTP_V0_EDID_GET, args, sizeof(*args));
+	NVIF_ERRON(ret, &outp->object, "[EDID_GET] size:%d", args->size);
+	if (ret)
+		goto done;
+
+	*pedid = kmalloc(args->size, GFP_KERNEL);
+	if (!*pedid) {
+		ret = -ENOMEM;
+		goto done;
+	}
+
+	memcpy(*pedid, args->data, args->size);
+	ret = args->size;
+done:
+	kfree(args);
+	return ret;
+}
+
 enum nvif_outp_detect_status
 nvif_outp_detect(struct nvif_outp *outp)
 {

drivers/gpu/drm/nouveau/nvkm/engine/disp/outp.h

@@ -87,6 +87,7 @@ struct nvkm_outp_func {
 	void (*fini)(struct nvkm_outp *);
 
 	int (*detect)(struct nvkm_outp *);
+	int (*edid_get)(struct nvkm_outp *, u8 *data, u16 *size);
 
 	int (*acquire)(struct nvkm_outp *);
 	void (*release)(struct nvkm_outp *);

drivers/gpu/drm/nouveau/nvkm/engine/disp/uoutp.c

@@ -275,6 +275,20 @@ nvkm_uoutp_mthd_load_detect(struct nvkm_outp *outp, void *argv, u32 argc)
 	return ret;
 }
 
+static int
+nvkm_uoutp_mthd_edid_get(struct nvkm_outp *outp, void *argv, u32 argc)
+{
+	union nvif_outp_edid_get_args *args = argv;
+
+	if (argc != sizeof(args->v0) || args->v0.version != 0)
+		return -ENOSYS;
+	if (!outp->func->edid_get)
+		return -EINVAL;
+
+	args->v0.size = ARRAY_SIZE(args->v0.data);
+	return outp->func->edid_get(outp, args->v0.data, &args->v0.size);
+}
+
 static int
 nvkm_uoutp_mthd_detect(struct nvkm_outp *outp, void *argv, u32 argc)
 {
@@ -319,6 +333,7 @@ nvkm_uoutp_mthd_noacquire(struct nvkm_outp *outp, u32 mthd, void *argv, u32 argc
 {
 	switch (mthd) {
 	case NVIF_OUTP_V0_DETECT     : return nvkm_uoutp_mthd_detect     (outp, argv, argc);
+	case NVIF_OUTP_V0_EDID_GET   : return nvkm_uoutp_mthd_edid_get   (outp, argv, argc);
 	case NVIF_OUTP_V0_ACQUIRE    : return nvkm_uoutp_mthd_acquire    (outp, argv, argc);
 	case NVIF_OUTP_V0_LOAD_DETECT: return nvkm_uoutp_mthd_load_detect(outp, argv, argc);
 	case NVIF_OUTP_V0_DP_AUX_PWR : return nvkm_uoutp_mthd_dp_aux_pwr (outp, argv, argc);