-----Original Message----- From: Alex Deucher alexdeucher@gmail.com Sent: 2020/February/25, Tuesday 9:07 AM To: Wentland, Harry Harry.Wentland@amd.com Cc: amd-gfx list amd-gfx@lists.freedesktop.org; Maling list - DRI developers dri-devel@lists.freedesktop.org; Deucher, Alexander Alexander.Deucher@amd.com; Broadworth, Mark Mark.Broadworth@amd.com; Liu, Zhan Zhan.Liu@amd.com Subject: Re: [PATCH 13/15] drm/amdgpu/display: split dp connector registration (v3)
On Mon, Feb 24, 2020 at 4:09 PM Harry Wentland hwentlan@amd.com wrote:
On 2020-02-07 4:17 p.m., Alex Deucher wrote:
Split into init and register functions to avoid a segfault in some configs when the load/unload callbacks are removed.
Looks like MST is completely broken with this change with a NULL pointer dereference in drm_dp_aux_register.
v2:
- add back accidently dropped has_aux setting
- set dev in late_register
v3:
- fix dp cec ordering
Signed-off-by: Alex Deucher alexander.deucher@amd.com
drivers/gpu/drm/amd/amdgpu/amdgpu_connectors.c | 16
++++++++++++++++
drivers/gpu/drm/amd/amdgpu/atombios_dp.c | 10 ++-------- .../amd/display/amdgpu_dm/amdgpu_dm_mst_types.c | 7 ++++++- 3 files changed, 24 insertions(+), 9 deletions(-)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_connectors.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_connectors.c index ec1501e3a63a..f355d9a752d2 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_connectors.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_connectors.c @@ -1461,6 +1461,20 @@ static enum drm_mode_status
amdgpu_connector_dp_mode_valid(struct drm_connector
return MODE_OK;}
+static int +amdgpu_connector_late_register(struct drm_connector *connector) {
struct amdgpu_connector *amdgpu_connector =to_amdgpu_connector(connector);
int r = 0;if (amdgpu_connector->ddc_bus->has_aux) {amdgpu_connector->ddc_bus->aux.dev = amdgpu_connector-base.kdev;
r = drm_dp_aux_register(&amdgpu_connector->ddc_bus->aux);}return r;+}
static const struct drm_connector_helper_funcs
amdgpu_connector_dp_helper_funcs = {
.get_modes = amdgpu_connector_dp_get_modes, .mode_valid = amdgpu_connector_dp_mode_valid, @@ -1475,6+1489,7 @@ static const struct drm_connector_funcs
amdgpu_connector_dp_funcs = {
.early_unregister = amdgpu_connector_unregister, .destroy = amdgpu_connector_destroy, .force = amdgpu_connector_dvi_force,
.late_register = amdgpu_connector_late_register,};
static const struct drm_connector_funcs amdgpu_connector_edp_funcs = { @@ -1485,6 +1500,7 @@ static const struct drm_connector_funcs
amdgpu_connector_edp_funcs = {
.early_unregister = amdgpu_connector_unregister, .destroy = amdgpu_connector_destroy, .force = amdgpu_connector_dvi_force,
.late_register = amdgpu_connector_late_register,};
void diff --git a/drivers/gpu/drm/amd/amdgpu/atombios_dp.c b/drivers/gpu/drm/amd/amdgpu/atombios_dp.c index ea702a64f807..9b74cfdba7b8 100644 --- a/drivers/gpu/drm/amd/amdgpu/atombios_dp.c +++ b/drivers/gpu/drm/amd/amdgpu/atombios_dp.c @@ -186,16 +186,10 @@ amdgpu_atombios_dp_aux_transfer(struct drm_dp_aux *aux, struct drm_dp_aux_msg *m
void amdgpu_atombios_dp_aux_init(struct amdgpu_connector *amdgpu_connector) {
int ret;amdgpu_connector->ddc_bus->rec.hpd = amdgpu_connector-hpd.hpd;
amdgpu_connector->ddc_bus->aux.dev = amdgpu_connector-base.kdev;
amdgpu_connector->ddc_bus->aux.transfer =amdgpu_atombios_dp_aux_transfer;
ret = drm_dp_aux_register(&amdgpu_connector->ddc_bus->aux);if (!ret)amdgpu_connector->ddc_bus->has_aux = true;WARN(ret, "drm_dp_aux_register_i2c_bus() failed with error %d\n",ret);
drm_dp_aux_init(&amdgpu_connector->ddc_bus->aux);amdgpu_connector->ddc_bus->has_aux = true;}
/***** general DP utility functions *****/ diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c index 3959c942c88b..d5b9e72f2649 100644
a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c
+++
b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c
@@ -155,6 +155,11 @@
amdgpu_dm_mst_connector_late_register(struct drm_connector *connector)
struct amdgpu_dm_connector *amdgpu_dm_connector = to_amdgpu_dm_connector(connector); struct drm_dp_mst_port *port = amdgpu_dm_connector->port;
int r;r = drm_dp_aux_register(&amdgpu_dm_connector->dm_dp_aux.aux);This calls drm_dp_aux_register_devnode which is also called later in drm_dp_mst_connector_late_register. Wonder if that's a problem.
Does this patch help? I'm not too familiar with the MST code and I don't have an MST monitor.
I have an MST monitor and I can give it a spin. I'll get back to you later.
Zhan
Alex
Harry
if (r)return r;#if defined(CONFIG_DEBUG_FS) connector_debugfs_init(amdgpu_dm_connector); @@ -484,7 +489,7 @@ void amdgpu_dm_initialize_dp_connector(struct
amdgpu_display_manager *dm,
aconnector->dm_dp_aux.aux.transfer = dm_dp_aux_transfer; aconnector->dm_dp_aux.ddc_service = aconnector->dc_link->ddc;
drm_dp_aux_register(&aconnector->dm_dp_aux.aux);
drm_dp_aux_init(&aconnector->dm_dp_aux.aux); drm_dp_cec_register_connector(&aconnector->dm_dp_aux.aux, &aconnector->base);