From 8b0e7e8f08513368767585ec3c9e9ef0a722f36a Mon Sep 17 00:00:00 2001
From: Lyude Paul <lyude@redhat.com>
Date: Fri, 19 Oct 2018 13:24:02 -0400
Subject: [PATCH] wip: drm/dp_mst: Add ->pre_enable/->post_disable() hooks
Some drivers, nouveau in particular, need to perform some hardware setup
before enabling the MST topology. Ideally, we want this setup to always
be done whenever topologies are enabled or disabled, even if it's not
because the driver choose to change the topology state. So, add some
hooks that get called under the main MST topology manager's lock and
implement said hooks in nouveau.
TODO: test this works
---
drivers/gpu/drm/drm_dp_mst_topology.c | 16 +++-
drivers/gpu/drm/nouveau/dispnv50/disp.c | 112 ++++++++++++------------
include/drm/drm_dp_mst_helper.h | 6 +-
3 files changed, 73 insertions(+), 61 deletions(-)
diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c
index 35c848535d097..3d421a60d1378 100644
--- a/drivers/gpu/drm/drm_dp_mst_topology.c
+++ b/drivers/gpu/drm/drm_dp_mst_topology.c
@@ -2233,6 +2233,12 @@ int drm_dp_mst_topology_mgr_set_mst(struct drm_dp_mst_topology_mgr *mgr, bool ms
if (mst_state) {
WARN_ON(mgr->mst_primary);
+ if (mgr->cbs->pre_enable) {
+ ret = mgr->cbs->pre_enable(mgr);
+ if (ret)
+ goto out_unlock;
+ }
+
/* get dpcd info */
ret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, mgr->dpcd, DP_RECEIVER_CAP_SIZE);
if (ret != DP_RECEIVER_CAP_SIZE) {
@@ -2277,13 +2283,16 @@ int drm_dp_mst_topology_mgr_set_mst(struct drm_dp_mst_topology_mgr *mgr, bool ms
mgr->mst_state = true;
ret = 0;
} else {
+ if (mgr->cbs->post_disable)
+ mgr->cbs->post_disable(mgr);
+
/* disable MST on the device */
mstb = mgr->mst_primary;
mgr->mst_primary = NULL;
/* this can fail if the device is gone */
drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL, 0);
- ret = 0;
- memset(mgr->payloads, 0, mgr->max_payloads * sizeof(struct drm_dp_payload));
+ memset(mgr->payloads, 0,
+ mgr->max_payloads * sizeof(struct drm_dp_payload));
mgr->payload_mask = 0;
set_bit(0, &mgr->payload_mask);
mgr->vcpi_mask = 0;
@@ -2291,6 +2300,9 @@ int drm_dp_mst_topology_mgr_set_mst(struct drm_dp_mst_topology_mgr *mgr, bool ms
}
out_unlock:
+ if (ret && mst_state && mgr->cbs->post_disable)
+ mgr->cbs->post_disable(mgr);
+
mutex_unlock(&mgr->lock);
if (mstb)
drm_dp_put_mst_branch_device(mstb);
diff --git a/drivers/gpu/drm/nouveau/dispnv50/disp.c b/drivers/gpu/drm/nouveau/dispnv50/disp.c
index 05a58cb36ceec..35c6efbdd8669 100644
--- a/drivers/gpu/drm/nouveau/dispnv50/disp.c
+++ b/drivers/gpu/drm/nouveau/dispnv50/disp.c
@@ -1128,12 +1128,62 @@ nv50_mstm_add_connector(struct drm_dp_mst_topology_mgr *mgr,
return &mstc->connector;
}
+static int
+nv50_mstm_enable(struct nv50_mstm *mstm, int state)
+{
+ struct nouveau_encoder *outp = mstm->outp;
+ struct {
+ struct nv50_disp_mthd_v1 base;
+ struct nv50_disp_sor_dp_mst_link_v0 mst;
+ } args = {
+ .base.version = 1,
+ .base.method = NV50_DISP_MTHD_V1_SOR_DP_MST_LINK,
+ .base.hasht = outp->dcb->hasht,
+ .base.hashm = outp->dcb->hashm,
+ .mst.state = state,
+ };
+ struct nouveau_drm *drm = nouveau_drm(outp->base.base.dev);
+ struct nvif_object *disp = &drm->display->disp.object;
+ int ret;
+
+ /* Even if we're enabling MST, start with disabling the branching unit
+ * to clear any sink-side MST topology state that wasn't set by us
+ */
+ ret = drm_dp_dpcd_writeb(mstm->mgr.aux, DP_MSTM_CTRL, 0);
+ if (ret < 0)
+ return ret;
+
+ if (state) {
+ /* Now, start initializing */
+ ret = drm_dp_dpcd_writeb(mstm->mgr.aux, DP_MSTM_CTRL,
+ DP_MST_EN);
+ if (ret < 0)
+ return ret;
+ }
+
+ return nvif_mthd(disp, 0, &args, sizeof(args));
+}
+
+static int
+nv50_mstm_pre_enable(struct drm_dp_mst_topology_mgr *mgr)
+{
+ return nv50_mstm_enable(nv50_mstm(mgr), true);
+}
+
+static void
+nv50_mstm_post_disable(struct drm_dp_mst_topology_mgr *mgr)
+{
+ nv50_mstm_enable(nv50_mstm(mgr), false);
+}
+
static const struct drm_dp_mst_topology_cbs
nv50_mstm = {
.add_connector = nv50_mstm_add_connector,
.register_connector = nv50_mstm_register_connector,
.destroy_connector = nv50_mstm_destroy_connector,
.hotplug = nv50_mstm_hotplug,
+ .pre_enable = nv50_mstm_pre_enable,
+ .post_disable = nv50_mstm_post_disable,
};
void
@@ -1169,42 +1219,6 @@ nv50_mstm_remove(struct nv50_mstm *mstm)
drm_dp_mst_topology_mgr_set_mst(&mstm->mgr, false);
}
-static int
-nv50_mstm_enable(struct nv50_mstm *mstm, int state)
-{
- struct nouveau_encoder *outp = mstm->outp;
- struct {
- struct nv50_disp_mthd_v1 base;
- struct nv50_disp_sor_dp_mst_link_v0 mst;
- } args = {
- .base.version = 1,
- .base.method = NV50_DISP_MTHD_V1_SOR_DP_MST_LINK,
- .base.hasht = outp->dcb->hasht,
- .base.hashm = outp->dcb->hashm,
- .mst.state = state,
- };
- struct nouveau_drm *drm = nouveau_drm(outp->base.base.dev);
- struct nvif_object *disp = &drm->display->disp.object;
- int ret;
-
- /* Even if we're enabling MST, start with disabling the branching unit
- * to clear any sink-side MST topology state that wasn't set by us
- */
- ret = drm_dp_dpcd_writeb(mstm->mgr.aux, DP_MSTM_CTRL, 0);
- if (ret < 0)
- return ret;
-
- if (state) {
- /* Now, start initializing */
- ret = drm_dp_dpcd_writeb(mstm->mgr.aux, DP_MSTM_CTRL,
- DP_MST_EN);
- if (ret < 0)
- return ret;
- }
-
- return nvif_mthd(disp, 0, &args, sizeof(args));
-}
-
int
nv50_mstm_detect(struct nv50_mstm *mstm, u8 dpcd[8], int allow)
{
@@ -1216,9 +1230,7 @@ nv50_mstm_detect(struct nv50_mstm *mstm, u8 dpcd[8], int allow)
if (!mstm)
return 0;
- mutex_lock(&mstm->mgr.lock);
-
- old_state = mstm->mgr.mst_state;
+ old_state = READ_ONCE(mstm->mgr.mst_state);
new_state = old_state;
aux = mstm->mgr.aux;
@@ -1232,7 +1244,7 @@ nv50_mstm_detect(struct nv50_mstm *mstm, u8 dpcd[8], int allow)
} else if (dpcd[0] >= 0x12) {
ret = drm_dp_dpcd_readb(aux, DP_MSTM_CAP, &dpcd[1]);
if (ret < 0)
- goto probe_error;
+ return ret;
if (!(dpcd[1] & DP_MST_CAP))
dpcd[0] = 0x11;
@@ -1240,26 +1252,10 @@ nv50_mstm_detect(struct nv50_mstm *mstm, u8 dpcd[8], int allow)
new_state = allow;
}
- if (new_state == old_state) {
- mutex_unlock(&mstm->mgr.lock);
+ if (new_state == old_state)
return new_state;
- }
-
- ret = nv50_mstm_enable(mstm, new_state);
- if (ret)
- goto probe_error;
- mutex_unlock(&mstm->mgr.lock);
-
- ret = drm_dp_mst_topology_mgr_set_mst(&mstm->mgr, new_state);
- if (ret)
- return nv50_mstm_enable(mstm, 0);
-
- return new_state;
-
-probe_error:
- mutex_unlock(&mstm->mgr.lock);
- return ret;
+ return drm_dp_mst_topology_mgr_set_mst(&mstm->mgr, new_state);
}
static void
diff --git a/include/drm/drm_dp_mst_helper.h b/include/drm/drm_dp_mst_helper.h
index c252e42677e5f..46292ed5f50ed 100644
--- a/include/drm/drm_dp_mst_helper.h
+++ b/include/drm/drm_dp_mst_helper.h
@@ -326,11 +326,15 @@ struct drm_dp_sideband_msg_tx {
struct drm_dp_mst_topology_mgr;
struct drm_dp_mst_topology_cbs {
/* create a connector for a port */
- struct drm_connector *(*add_connector)(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port, const char *path);
+ struct drm_connector *(*add_connector)(struct drm_dp_mst_topology_mgr *mgr,
+ struct drm_dp_mst_port *port,
+ const char *path);
void (*register_connector)(struct drm_connector *connector);
void (*destroy_connector)(struct drm_dp_mst_topology_mgr *mgr,
struct drm_connector *connector);
void (*hotplug)(struct drm_dp_mst_topology_mgr *mgr);
+ int (*pre_enable)(struct drm_dp_mst_topology_mgr *mgr);
+ void (*post_disable)(struct drm_dp_mst_topology_mgr *mgr);
};
--
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