Hi,
On 25/10/2019 15:29, Neil Armstrong wrote: > On 23/10/2019 17:44, Boris Brezillon wrote: >> So that each element in the chain can easily access its predecessor. >> This will be needed to support bus format negotiation between elements >> of the bridge chain. >> >> Signed-off-by: Boris Brezillon <[email protected]> >> --- >> Changes in v3: >> * None >> >> Changes in v2: >> * Adjust things to the "dummy encoder bridge" change (patch 2 in this >> series) >> --- >> drivers/gpu/drm/drm_bridge.c | 171 ++++++++++++++++++++++------------ >> drivers/gpu/drm/drm_encoder.c | 16 +--- >> include/drm/drm_bridge.h | 12 ++- >> include/drm/drm_encoder.h | 9 +- >> 4 files changed, 135 insertions(+), 73 deletions(-) >> >> diff --git a/drivers/gpu/drm/drm_bridge.c b/drivers/gpu/drm/drm_bridge.c >> index 54c874493c57..c5cf8a9c4237 100644 >> --- a/drivers/gpu/drm/drm_bridge.c >> +++ b/drivers/gpu/drm/drm_bridge.c [...] >> >> @@ -426,15 +471,23 @@ EXPORT_SYMBOL(drm_atomic_bridge_chain_post_disable); >> void drm_atomic_bridge_chain_pre_enable(struct drm_bridge *bridge, >> struct drm_atomic_state *state) >> { >> + struct drm_encoder *encoder; >> + struct drm_bridge *iter; >> + >> if (!bridge) >> return; >> >> - drm_atomic_bridge_chain_pre_enable(bridge->next, state); >> + encoder = bridge->encoder; >> + list_for_each_entry_reverse(iter, &bridge->encoder->bridge_chain, >> + chain_node) { This should use the encoder local variable in list_for_each_entry_reverse() >> + if (iter->funcs->atomic_pre_enable) >> + iter->funcs->atomic_pre_enable(iter, state); >> + else if (iter->funcs->pre_enable) >> + iter->funcs->pre_enable(iter); >> >> - if (bridge->funcs->atomic_pre_enable) >> - bridge->funcs->atomic_pre_enable(bridge, state); >> - else if (bridge->funcs->pre_enable) >> - bridge->funcs->pre_enable(bridge); >> + if (iter == bridge) >> + break; >> + } >> } >> EXPORT_SYMBOL(drm_atomic_bridge_chain_pre_enable); >> >> @@ -453,15 +506,19 @@ EXPORT_SYMBOL(drm_atomic_bridge_chain_pre_enable); >> void drm_atomic_bridge_chain_enable(struct drm_bridge *bridge, >> struct drm_atomic_state *state) >> { >> + struct drm_encoder *encoder; >> + >> if (!bridge) >> return; >> >> - if (bridge->funcs->atomic_enable) >> - bridge->funcs->atomic_enable(bridge, state); >> - else if (bridge->funcs->enable) >> - bridge->funcs->enable(bridge); >> - >> - drm_atomic_bridge_chain_enable(bridge->next, state); >> + encoder = bridge->encoder; >> + list_for_each_entry_from(bridge, &bridge->encoder->bridge_chain, >> + chain_node) { This should use encoder instead of bridge->encoder otherwise bridge will change and bridge->encoder->bridge_chain won't be valid during the for_each and cause the following : [ 79.082861] WARNING: CPU: 2 PID: 1999 at drivers/gpu/drm/drm_bridge.c:607 drm_atomic_bridge_chain_enable+0xac/0xc0 ... [ 79.210153] drm_atomic_bridge_chain_enable+0xac/0xc0 [ 79.215156] drm_atomic_helper_commit_modeset_enables+0x138/0x248 [ 79.221190] drm_atomic_helper_commit_tail_rpm+0x2c/0x78 [ 79.226452] commit_tail+0x50/0xc0 [ 79.229815] drm_atomic_helper_commit+0xe8/0x168 [ 79.234386] drm_atomic_commit+0x48/0x58 [ 79.238269] drm_client_modeset_commit_atomic.isra.15+0x184/0x220 [ 79.244305] drm_client_modeset_commit_force+0x64/0x1a0 [ 79.249482] drm_fb_helper_restore_fbdev_mode_unlocked+0x70/0xe8 [ 79.255432] drm_fbdev_client_restore+0x14/0x20 [ 79.259920] drm_client_dev_restore+0x80/0xd8 [ 79.264231] drm_lastclose+0x4c/0x58 [ 79.267765] drm_release+0xa8/0x178 >> + if (bridge->funcs->atomic_enable) >> + bridge->funcs->atomic_enable(bridge, state); >> + else if (bridge->funcs->enable) >> + bridge->funcs->enable(bridge); >> + } >> } >> EXPORT_SYMBOL(drm_atomic_bridge_chain_enable); >> >> diff --git a/drivers/gpu/drm/drm_encoder.c b/drivers/gpu/drm/drm_encoder.c >> index 4fe9e723e227..e555281f43d4 100644 >> --- a/drivers/gpu/drm/drm_encoder.c >> +++ b/drivers/gpu/drm/drm_encoder.c >> @@ -140,6 +140,7 @@ int drm_encoder_init(struct drm_device *dev, >> goto out_put; >> } >> >> + INIT_LIST_HEAD(&encoder->bridge_chain); >> list_add_tail(&encoder->head, &dev->mode_config.encoder_list); >> encoder->index = dev->mode_config.num_encoder++; >> >> @@ -160,23 +161,16 @@ EXPORT_SYMBOL(drm_encoder_init); >> void drm_encoder_cleanup(struct drm_encoder *encoder) >> { >> struct drm_device *dev = encoder->dev; >> + struct drm_bridge *bridge, *next; >> >> /* Note that the encoder_list is considered to be static; should we >> * remove the drm_encoder at runtime we would have to decrement all >> * the indices on the drm_encoder after us in the encoder_list. >> */ >> >> - if (encoder->bridge) { >> - struct drm_bridge *bridge; >> - struct drm_bridge *next; >> - >> - bridge = drm_bridge_chain_get_first_bridge(encoder); >> - while (bridge) { >> - next = bridge->next; >> - drm_bridge_detach(bridge); >> - bridge = next; >> - } >> - } >> + list_for_each_entry_safe(bridge, next, &encoder->bridge_chain, >> + chain_node) >> + drm_bridge_detach(bridge); >> >> drm_mode_object_unregister(dev, &encoder->base); >> kfree(encoder->name); >> diff --git a/include/drm/drm_bridge.h b/include/drm/drm_bridge.h >> index 27eef63ce0ff..3ab16c95e59e 100644 >> --- a/include/drm/drm_bridge.h >> +++ b/include/drm/drm_bridge.h >> @@ -384,8 +384,8 @@ struct drm_bridge { >> struct drm_device *dev; >> /** @encoder: encoder to which this bridge is connected */ >> struct drm_encoder *encoder; >> - /** @next: the next bridge in the encoder chain */ >> - struct drm_bridge *next; >> + /** @chain_node: used to form a bridge chain */ >> + struct list_head chain_node; >> #ifdef CONFIG_OF >> /** @of_node: device node pointer to the bridge */ >> struct device_node *of_node; >> @@ -420,7 +420,10 @@ int drm_bridge_attach(struct drm_encoder *encoder, >> struct drm_bridge *bridge, >> static inline struct drm_bridge * >> drm_bridge_chain_get_next_bridge(struct drm_bridge *bridge) >> { >> - return bridge->next; >> + if (list_is_last(&bridge->chain_node, &bridge->encoder->bridge_chain)) >> + return NULL; >> + >> + return list_next_entry(bridge, chain_node); >> } >> >> /** >> @@ -434,7 +437,8 @@ drm_bridge_chain_get_next_bridge(struct drm_bridge >> *bridge) >> static inline struct drm_bridge * >> drm_bridge_chain_get_first_bridge(struct drm_encoder *encoder) >> { >> - return encoder->bridge; >> + return list_first_entry_or_null(&encoder->bridge_chain, >> + struct drm_bridge, chain_node); >> } >> >> bool drm_bridge_chain_mode_fixup(struct drm_bridge *bridge, >> diff --git a/include/drm/drm_encoder.h b/include/drm/drm_encoder.h >> index f06164f44efe..9b3dde177c81 100644 >> --- a/include/drm/drm_encoder.h >> +++ b/include/drm/drm_encoder.h >> @@ -172,7 +172,14 @@ struct drm_encoder { >> * &drm_connector_state.crtc. >> */ >> struct drm_crtc *crtc; >> - struct drm_bridge *bridge; >> + >> + /** >> + * @bridge_chain: Bridges attached to this encoder. The first entry of >> + * this list is always &drm_encoder.bridge. It may be followed by other >> + * bridge entities. >> + */ >> + struct list_head bridge_chain; >> + >> const struct drm_encoder_funcs *funcs; >> const struct drm_encoder_helper_funcs *helper_private; >> }; >> > > Reviewed-by: Neil Armstrong <[email protected]> > With these fixed, you can keep my Reviewed-by Neil _______________________________________________ dri-devel mailing list [email protected] https://lists.freedesktop.org/mailman/listinfo/dri-devel
