On 2025-07-25 20:33, Melissa Wen wrote:
> Reduce direct handling of edid data by resorting to drm helpers that
> deal with this info inside drm_edid infrastructure.
> 
> v3:
> - use dc_edid_sink_edid_free in link_detection
> 
> v5:
> - no need of drm_edid duplication (Mario)
> - fix mem leak on dc_sink->drm_edid
> 
> v6:
> - fix NULL pointer dereference (Alex H)
> 
> Signed-off-by: Melissa Wen <m...@igalia.com>
> ---
>  .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 26 ++++++---------
>  .../amd/display/amdgpu_dm/amdgpu_dm_helpers.c | 31 ++++++------------
>  .../display/amdgpu_dm/amdgpu_dm_mst_types.c   | 21 ++++--------
>  .../gpu/drm/amd/display/amdgpu_dm/dc_edid.c   | 32 +++++++++++--------
>  .../gpu/drm/amd/display/amdgpu_dm/dc_edid.h   |  1 +
>  .../drm/amd/display/dc/link/link_detection.c  |  3 +-
>  6 files changed, 48 insertions(+), 66 deletions(-)
> 
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c 
> b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> index 878269c2092c..1aa0ccf74580 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> @@ -68,6 +68,7 @@
>  #endif
>  #include "amdgpu_dm_psr.h"
>  #include "amdgpu_dm_replay.h"
> +#include "dc_edid.h"
>  
>  #include "ivsrcid/ivsrcid_vislands30.h"
>  
> @@ -3743,6 +3744,8 @@ void amdgpu_dm_update_connector_after_detect(
>        * 2. Send an event and let userspace tell us what to do
>        */
>       if (sink) {
> +             const struct drm_edid *drm_edid = sink->drm_edid;
> +
>               /*
>                * TODO: check if we still need the S3 mode update workaround.
>                * If yes, put it here.
> @@ -3754,16 +3757,15 @@ void amdgpu_dm_update_connector_after_detect(
>  
>               aconnector->dc_sink = sink;
>               dc_sink_retain(aconnector->dc_sink);
> -             if (sink->dc_edid.length == 0) {
> +
> +             if (!drm_edid_valid(drm_edid)) {
>                       aconnector->drm_edid = NULL;
>                       hdmi_cec_unset_edid(aconnector);
>                       if (aconnector->dc_link->aux_mode) {
>                               
> drm_dp_cec_unset_edid(&aconnector->dm_dp_aux.aux);
>                       }
>               } else {
> -                     const struct edid *edid = (const struct edid 
> *)sink->dc_edid.raw_edid;
> -
> -                     aconnector->drm_edid = drm_edid_alloc(edid, 
> sink->dc_edid.length);
> +                     aconnector->drm_edid = drm_edid_dup(sink->drm_edid);
>                       drm_edid_connector_update(connector, 
> aconnector->drm_edid);
>  
>                       hdmi_cec_set_edid(aconnector);
> @@ -7434,12 +7436,8 @@ static void amdgpu_dm_connector_funcs_force(struct 
> drm_connector *connector)
>       aconnector->drm_edid = drm_edid;
>       /* Update emulated (virtual) sink's EDID */
>       if (dc_em_sink && dc_link) {
> -             // FIXME: Get rid of drm_edid_raw()
> -             const struct edid *edid = drm_edid_raw(drm_edid);
> -
>               memset(&dc_em_sink->edid_caps, 0, sizeof(struct dc_edid_caps));
> -             memmove(dc_em_sink->dc_edid.raw_edid, edid,
> -                     (edid->extensions + 1) * EDID_LENGTH);
> +             dc_edid_copy_edid_to_dc(dc_em_sink, drm_edid, 0);
>               dm_helpers_parse_edid_caps(dc_link, dc_em_sink);
>       }
>  }
> @@ -7472,7 +7470,6 @@ static void create_eml_sink(struct amdgpu_dm_connector 
> *aconnector)
>                       .sink_signal = SIGNAL_TYPE_VIRTUAL
>       };
>       const struct drm_edid *drm_edid;
> -     const struct edid *edid;
>       struct i2c_adapter *ddc;
>  
>       if (dc_link && dc_link->aux_mode)
> @@ -7492,12 +7489,9 @@ static void create_eml_sink(struct amdgpu_dm_connector 
> *aconnector)
>  
>       aconnector->drm_edid = drm_edid;
>  
> -     edid = drm_edid_raw(drm_edid); // FIXME: Get rid of drm_edid_raw()
> -     aconnector->dc_em_sink = dc_link_add_remote_sink(
> -             aconnector->dc_link,
> -             (uint8_t *)edid,
> -             (edid->extensions + 1) * EDID_LENGTH,
> -             &init_params);
> +     aconnector->dc_em_sink = dc_link_add_remote_sink(aconnector->dc_link,
> +                                                      drm_edid, 0,
> +                                                      &init_params);
>  
>       if (aconnector->base.force == DRM_FORCE_ON) {
>               aconnector->dc_sink = aconnector->dc_link->local_sink ?
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c 
> b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
> index d4d60d62964c..288e87f92f9e 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
> @@ -48,6 +48,7 @@
>  #include "dm_helpers.h"
>  #include "ddc_service_types.h"
>  #include "clk_mgr.h"
> +#include "dc_edid.h"
>  
>  static void apply_edid_quirks(struct drm_device *dev,
>                             const struct drm_edid *drm_edid,
> @@ -100,20 +101,16 @@ enum dc_edid_status dm_helpers_parse_edid_caps(struct 
> dc_link *link,
>       struct amdgpu_dm_connector *aconnector = link->priv;
>       struct drm_connector *connector = &aconnector->base;
>       struct drm_device *dev = connector->dev;
> -     struct edid *edid_buf;
> -     const struct drm_edid *drm_edid;
> +     const struct drm_edid *drm_edid = sink->drm_edid;
>       struct drm_edid_product_id product_id;
>       struct dc_edid_caps *edid_caps = &sink->edid_caps;
>       int sad_count;
>       int i = 0;
>       enum dc_edid_status result = EDID_OK;
>  
> -     edid_buf = (struct edid *) &sink->dc_edid.raw_edid;
> -     if (!edid_caps || !edid_buf)
> +     if (!edid_caps || !drm_edid)
>               return EDID_BAD_INPUT;
>  
> -     drm_edid = drm_edid_alloc(edid_buf, EDID_LENGTH * (edid_buf->extensions 
> + 1));
> -
>       if (!drm_edid_valid(drm_edid))
>               result = EDID_BAD_CHECKSUM;
>  
> @@ -135,10 +132,8 @@ enum dc_edid_status dm_helpers_parse_edid_caps(struct 
> dc_link *link,
>       apply_edid_quirks(dev, drm_edid, edid_caps);
>  
>       sad_count = drm_eld_sad_count(connector->eld);
> -     if (sad_count <= 0) {
> -             drm_edid_free(drm_edid);
> +     if (sad_count <= 0)
>               return result;
> -     }
>  
>       edid_caps->audio_mode_count = min(sad_count, DC_MAX_AUDIO_DESC_COUNT);
>       for (i = 0; i < edid_caps->audio_mode_count; ++i) {
> @@ -158,8 +153,6 @@ enum dc_edid_status dm_helpers_parse_edid_caps(struct 
> dc_link *link,
>       else
>               edid_caps->speaker_flags = DEFAULT_SPEAKER_LOCATION;
>  
> -     drm_edid_free(drm_edid);
> -
>       return result;
>  }
>  
> @@ -991,7 +984,6 @@ enum dc_edid_status dm_helpers_read_local_edid(
>       int retry = 3;
>       enum dc_edid_status edid_status;
>       const struct drm_edid *drm_edid;
> -     const struct edid *edid;
>  
>       if (link->aux_mode)
>               ddc = &aconnector->dm_dp_aux.aux.ddc;
> @@ -1002,6 +994,8 @@ enum dc_edid_status dm_helpers_read_local_edid(
>        * do check sum and retry to make sure read correct edid.
>        */
>       do {
> +             drm_edid_free(sink->drm_edid);
> +
>               drm_edid = dm_helpers_read_acpi_edid(aconnector);
>               if (drm_edid)
>                       drm_info(connector->dev, "Using ACPI provided EDID for 
> %s\n", connector->name);
> @@ -1021,16 +1015,7 @@ enum dc_edid_status dm_helpers_read_local_edid(
>               if (!drm_edid)
>                       return EDID_NO_RESPONSE;
>  
> -             edid = drm_edid_raw(drm_edid); // FIXME: Get rid of 
> drm_edid_raw()
> -             if (!edid ||
> -                 edid->extensions >= sizeof(sink->dc_edid.raw_edid) / 
> EDID_LENGTH)
> -                     return EDID_BAD_INPUT;
> -
> -             sink->dc_edid.length = EDID_LENGTH * (edid->extensions + 1);
> -             memmove(sink->dc_edid.raw_edid, (uint8_t *)edid, 
> sink->dc_edid.length);
> -
> -             /* We don't need the original edid anymore */
> -             drm_edid_free(drm_edid);
> +             sink->drm_edid = drm_edid;
>  
>               edid_status = dm_helpers_parse_edid_caps(link, sink);
>  
> @@ -1055,6 +1040,8 @@ enum dc_edid_status dm_helpers_read_local_edid(
>  
>               test_response.bits.EDID_CHECKSUM_WRITE = 1;
>  
> +             // TODO: drm_edid doesn't have a helper for dp_write_dpcd yet
> +             dc_edid_copy_edid_to_sink(sink);
>               dm_helpers_dp_write_dpcd(ctx,
>                                       link,
>                                       DP_TEST_EDID_CHECKSUM,
> 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 7187d5aedf0a..5ca3e668c8aa 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
> @@ -359,12 +359,10 @@ static int dm_dp_mst_get_modes(struct drm_connector 
> *connector)
>                                       .link = aconnector->dc_link,
>                                       .sink_signal = 
> SIGNAL_TYPE_DISPLAY_PORT_MST };
>  
> -                             dc_sink = dc_link_add_remote_sink(
> -                                     aconnector->dc_link,
> -                                     NULL,
> -                                     0,
> -                                     &init_params);
> -
> +                             dc_sink = 
> dc_link_add_remote_sink(aconnector->dc_link,
> +                                                               NULL,
> +                                                               0,
> +                                                               &init_params);
>                               if (!dc_sink) {
>                                       DRM_ERROR("Unable to add a remote 
> sink\n");
>                                       return 0;
> @@ -397,15 +395,10 @@ static int dm_dp_mst_get_modes(struct drm_connector 
> *connector)
>               struct dc_sink_init_data init_params = {
>                               .link = aconnector->dc_link,
>                               .sink_signal = SIGNAL_TYPE_DISPLAY_PORT_MST };
> -             const struct edid *edid;
> -
> -             edid = drm_edid_raw(aconnector->drm_edid); // FIXME: Get rid of 
> drm_edid_raw()
> -             dc_sink = dc_link_add_remote_sink(
> -                     aconnector->dc_link,
> -                     (uint8_t *)edid,
> -                     (edid->extensions + 1) * EDID_LENGTH,
> -                     &init_params);
>  
> +             dc_sink = dc_link_add_remote_sink(aconnector->dc_link,
> +                                               aconnector->drm_edid, 0,
> +                                               &init_params);
>               if (!dc_sink) {
>                       DRM_ERROR("Unable to add a remote sink\n");
>                       return 0;
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/dc_edid.c 
> b/drivers/gpu/drm/amd/display/amdgpu_dm/dc_edid.c
> index 493815829aa5..d89a82c349fa 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/dc_edid.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/dc_edid.c
> @@ -6,25 +6,31 @@
>  bool dc_edid_is_same_edid(struct dc_sink *prev_sink,
>                         struct dc_sink *current_sink)
>  {
> -     struct dc_edid *old_edid = &prev_sink->dc_edid;
> -     struct dc_edid *new_edid = &current_sink->dc_edid;
> -
> -       if (old_edid->length != new_edid->length)
> -               return false;
> -
> -       if (new_edid->length == 0)
> -               return false;
> -
> -       return (memcmp(old_edid->raw_edid,
> -                      new_edid->raw_edid, new_edid->length) == 0);
> +     return drm_edid_eq(prev_sink->drm_edid, current_sink->drm_edid);

DC is OS agnostic. There is no drm_ on other OSes.

>  }
>  
>  void dc_edid_copy_edid_to_dc(struct dc_sink *dc_sink,
>                            const void *edid,
>                            int len)
>  {
> -     memmove(dc_sink->dc_edid.raw_edid, edid, len);
> -     dc_sink->dc_edid.length = len;
> +     dc_sink->drm_edid = drm_edid_dup((const struct drm_edid *) edid);

Same here.

> +}
> +
> +void dc_edid_copy_edid_to_sink(struct dc_sink *sink)
> +{
> +     const struct edid *edid;
> +
> +     edid = drm_edid_raw(sink->drm_edid); // FIXME: Get rid of drm_edid_raw()

And here.

Harry

> +     if (!edid ||
> +         edid->extensions >= sizeof(sink->dc_edid.raw_edid) / EDID_LENGTH) {
> +             memset(sink->dc_edid.raw_edid, 0, 
> sizeof(sink->dc_edid.raw_edid));
> +             sink->dc_edid.length = 0;
> +             return;
> +     }
> +
> +     sink->dc_edid.length = EDID_LENGTH * (edid->extensions + 1);
> +     memcpy(sink->dc_edid.raw_edid, (uint8_t *) edid,
> +            sink->dc_edid.length);
>  }
>  
>  void dc_edid_sink_edid_free(struct dc_sink *sink)
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/dc_edid.h 
> b/drivers/gpu/drm/amd/display/amdgpu_dm/dc_edid.h
> index 2c76768be459..a95cc6ccc743 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/dc_edid.h
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/dc_edid.h
> @@ -9,6 +9,7 @@ bool dc_edid_is_same_edid(struct dc_sink *prev_sink,
>                         struct dc_sink *current_sink);
>  void dc_edid_copy_edid_to_dc(struct dc_sink *dc_sink,
>                            const void *edid, int len);
> +void dc_edid_copy_edid_to_sink(struct dc_sink *sink);
>  void dc_edid_sink_edid_free(struct dc_sink *sink);
>  
>  #endif /* __DC_EDID_H__ */
> diff --git a/drivers/gpu/drm/amd/display/dc/link/link_detection.c 
> b/drivers/gpu/drm/amd/display/dc/link/link_detection.c
> index 0fcdf803b7a0..5df87d39903e 100644
> --- a/drivers/gpu/drm/amd/display/dc/link/link_detection.c
> +++ b/drivers/gpu/drm/amd/display/dc/link/link_detection.c
> @@ -1134,6 +1134,7 @@ static bool detect_link_and_local_sink(struct dc_link 
> *link,
>                       dp_trace_init(link);
>  
>               /* Connectivity log: detection */
> +             dc_edid_copy_edid_to_sink(sink);
>               for (i = 0; i < sink->dc_edid.length / DC_EDID_BLOCK_SIZE; i++) 
> {
>                       CONN_DATA_DETECT(link,
>                                        &sink->dc_edid.raw_edid[i * 
> DC_EDID_BLOCK_SIZE],
> @@ -1416,7 +1417,7 @@ struct dc_sink *link_add_remote_sink(
>        * parsing fails
>        */
>       if (edid_status != EDID_OK && edid_status != EDID_PARTIAL_VALID) {
> -             dc_sink->dc_edid.length = 0;
> +             dc_edid_sink_edid_free(dc_sink);
>               dm_error("Bad EDID, status%d!\n", edid_status);
>       }
>  

Reply via email to