To properly test the EDID reading without using the DRM override, add an
option to configure the EDID for a connector.
Signed-off-by: Louis Chauvet <louis.chauvet@bootlin.com>
---
drivers/gpu/drm/vkms/vkms_config.c | 1 +
drivers/gpu/drm/vkms/vkms_config.h | 2 ++
drivers/gpu/drm/vkms/vkms_output.c | 37 ++++++++++++++++++++++++++++++++++---
3 files changed, 37 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/vkms/vkms_config.c b/drivers/gpu/drm/vkms/vkms_config.c
index ac1a9658c5075c118d59da965ca3392355ccb2b2..1a1234d4f10fa8e5ea6bd649139ecc10c991f875 100644
--- a/drivers/gpu/drm/vkms/vkms_config.c
+++ b/drivers/gpu/drm/vkms/vkms_config.c
@@ -199,6 +199,7 @@ struct vkms_config_connector *vkms_config_create_connector(struct vkms_config *v
xa_init_flags(&vkms_config_connector->possible_encoders, XA_FLAGS_ALLOC);
vkms_config_connector->type = DRM_MODE_CONNECTOR_VIRTUAL;
vkms_config_connector->status = connector_status_unknown;
+ vkms_config_connector->edid_blob_len = 0;
return vkms_config_connector;
}
diff --git a/drivers/gpu/drm/vkms/vkms_config.h b/drivers/gpu/drm/vkms/vkms_config.h
index bba56c9d8aeceac97a4339ef42ab663c5dc54e65..1220b16f6c98d1ebb0ae55d662a84fe25e1a6a02 100644
--- a/drivers/gpu/drm/vkms/vkms_config.h
+++ b/drivers/gpu/drm/vkms/vkms_config.h
@@ -112,6 +112,8 @@ struct vkms_config_connector {
struct xarray possible_encoders;
int type;
enum drm_connector_status status;
+ char edid_blob[PAGE_SIZE];
+ int edid_blob_len;
/* Internal usage */
struct drm_connector *connector;
diff --git a/drivers/gpu/drm/vkms/vkms_output.c b/drivers/gpu/drm/vkms/vkms_output.c
index fc6a0cdade0739b94820ed4e0924cf355137fe79..56590afb33d75465971d10a282040690840cdbee 100644
--- a/drivers/gpu/drm/vkms/vkms_output.c
+++ b/drivers/gpu/drm/vkms/vkms_output.c
@@ -31,13 +31,44 @@ static const struct drm_connector_funcs vkms_connector_funcs = {
.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
};
+static int vkms_connector_read_block(void *context, u8 *buf, unsigned int block, size_t len)
+{
+ struct vkms_config_connector *config = context;
+
+ if (block * len + len > config->edid_blob_len)
+ return 1;
+ memcpy(buf, &config->edid_blob[block * len], len);
+ return 0;
+}
+
static int vkms_conn_get_modes(struct drm_connector *connector)
{
+ const struct drm_edid *drm_edid = NULL;
int count;
+ struct vkms_config_connector *connector_cfg;
+ struct vkms_device *vkmsdev = drm_device_to_vkms_device(connector->dev);
+ struct vkms_config_connector *context = NULL;
+
+ list_for_each_entry(connector_cfg, &vkmsdev->config->connectors, link) {
+ if (connector_cfg->connector == connector) {
+ context = connector_cfg;
+ break;
+ }
+ }
+ if (context)
+ drm_edid = drm_edid_read_custom(connector, vkms_connector_read_block, context);
+
+ /*
+ * Unconditionally update the connector. If the EDID was read
+ * successfully, fill in the connector information derived from the
+ * EDID. Otherwise, if the EDID is NULL, clear the connector
+ * information.
+ */
+ drm_edid_connector_update(connector, drm_edid);
+
+ count = drm_edid_connector_add_modes(connector);
- /* Use the default modes list from DRM */
- count = drm_add_modes_noedid(connector, XRES_MAX, YRES_MAX);
- drm_set_preferred_mode(connector, XRES_DEF, YRES_DEF);
+ drm_edid_free(drm_edid);
return count;
}
--
2.47.0On Fri, 22 Nov 2024, Louis Chauvet <louis.chauvet@bootlin.com> wrote:
> To properly test the EDID reading without using the DRM override, add an
> option to configure the EDID for a connector.
>
> Signed-off-by: Louis Chauvet <louis.chauvet@bootlin.com>
> ---
> drivers/gpu/drm/vkms/vkms_config.c | 1 +
> drivers/gpu/drm/vkms/vkms_config.h | 2 ++
> drivers/gpu/drm/vkms/vkms_output.c | 37 ++++++++++++++++++++++++++++++++++---
> 3 files changed, 37 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/gpu/drm/vkms/vkms_config.c b/drivers/gpu/drm/vkms/vkms_config.c
> index ac1a9658c5075c118d59da965ca3392355ccb2b2..1a1234d4f10fa8e5ea6bd649139ecc10c991f875 100644
> --- a/drivers/gpu/drm/vkms/vkms_config.c
> +++ b/drivers/gpu/drm/vkms/vkms_config.c
> @@ -199,6 +199,7 @@ struct vkms_config_connector *vkms_config_create_connector(struct vkms_config *v
> xa_init_flags(&vkms_config_connector->possible_encoders, XA_FLAGS_ALLOC);
> vkms_config_connector->type = DRM_MODE_CONNECTOR_VIRTUAL;
> vkms_config_connector->status = connector_status_unknown;
> + vkms_config_connector->edid_blob_len = 0;
>
> return vkms_config_connector;
> }
> diff --git a/drivers/gpu/drm/vkms/vkms_config.h b/drivers/gpu/drm/vkms/vkms_config.h
> index bba56c9d8aeceac97a4339ef42ab663c5dc54e65..1220b16f6c98d1ebb0ae55d662a84fe25e1a6a02 100644
> --- a/drivers/gpu/drm/vkms/vkms_config.h
> +++ b/drivers/gpu/drm/vkms/vkms_config.h
> @@ -112,6 +112,8 @@ struct vkms_config_connector {
> struct xarray possible_encoders;
> int type;
> enum drm_connector_status status;
> + char edid_blob[PAGE_SIZE];
> + int edid_blob_len;
>
> /* Internal usage */
> struct drm_connector *connector;
> diff --git a/drivers/gpu/drm/vkms/vkms_output.c b/drivers/gpu/drm/vkms/vkms_output.c
> index fc6a0cdade0739b94820ed4e0924cf355137fe79..56590afb33d75465971d10a282040690840cdbee 100644
> --- a/drivers/gpu/drm/vkms/vkms_output.c
> +++ b/drivers/gpu/drm/vkms/vkms_output.c
> @@ -31,13 +31,44 @@ static const struct drm_connector_funcs vkms_connector_funcs = {
> .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
> };
>
> +static int vkms_connector_read_block(void *context, u8 *buf, unsigned int block, size_t len)
> +{
> + struct vkms_config_connector *config = context;
> +
> + if (block * len + len > config->edid_blob_len)
The parameters to the read block function are a bit weird for historical
reasons. The start offset is indicated by block number, length by
len. The start byte offset is thus block * EDID_LENGTH! There's no
smaller granularity for start offset. However len can be < EDID_LENGTH!
So the above should be (block * EDID_LENGTH + len > edid_blob_len)
> + return 1;
> + memcpy(buf, &config->edid_blob[block * len], len);
And this should be &config->edid_blob[block * EDID_LENGTH].
(Your patch would work, but just by coincidence due to the way the read
block function is currently called.)
> + return 0;
> +}
> +
> static int vkms_conn_get_modes(struct drm_connector *connector)
> {
> + const struct drm_edid *drm_edid = NULL;
> int count;
> + struct vkms_config_connector *connector_cfg;
> + struct vkms_device *vkmsdev = drm_device_to_vkms_device(connector->dev);
> + struct vkms_config_connector *context = NULL;
> +
> + list_for_each_entry(connector_cfg, &vkmsdev->config->connectors, link) {
> + if (connector_cfg->connector == connector) {
> + context = connector_cfg;
> + break;
> + }
> + }
> + if (context)
> + drm_edid = drm_edid_read_custom(connector, vkms_connector_read_block, context);
Thanks for using drm_edid_read_custom() for this btw!
> +
> + /*
> + * Unconditionally update the connector. If the EDID was read
> + * successfully, fill in the connector information derived from the
> + * EDID. Otherwise, if the EDID is NULL, clear the connector
> + * information.
> + */
> + drm_edid_connector_update(connector, drm_edid);
> +
> + count = drm_edid_connector_add_modes(connector);
>
> - /* Use the default modes list from DRM */
> - count = drm_add_modes_noedid(connector, XRES_MAX, YRES_MAX);
> - drm_set_preferred_mode(connector, XRES_DEF, YRES_DEF);
I don't really know anything about your use case, but don't you want to
fall back to the above for drm_edid == NULL? *shrug*
BR,
Jani.
> + drm_edid_free(drm_edid);
>
> return count;
> }
--
Jani Nikula, Intel
Le 25 novembre 2024 09:45:04 UTC, Jani Nikula <jani.nikula@linux.intel.com> a écrit :
>On Fri, 22 Nov 2024, Louis Chauvet <louis.chauvet@bootlin.com> wrote:
>> To properly test the EDID reading without using the DRM override, add an
>> option to configure the EDID for a connector.
>>
>> Signed-off-by: Louis Chauvet <louis.chauvet@bootlin.com>
>> ---
>> drivers/gpu/drm/vkms/vkms_config.c | 1 +
>> drivers/gpu/drm/vkms/vkms_config.h | 2 ++
>> drivers/gpu/drm/vkms/vkms_output.c | 37 ++++++++++++++++++++++++++++++++++---
>> 3 files changed, 37 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/vkms/vkms_config.c b/drivers/gpu/drm/vkms/vkms_config.c
>> index ac1a9658c5075c118d59da965ca3392355ccb2b2..1a1234d4f10fa8e5ea6bd649139ecc10c991f875 100644
>> --- a/drivers/gpu/drm/vkms/vkms_config.c
>> +++ b/drivers/gpu/drm/vkms/vkms_config.c
>> @@ -199,6 +199,7 @@ struct vkms_config_connector *vkms_config_create_connector(struct vkms_config *v
>> xa_init_flags(&vkms_config_connector->possible_encoders, XA_FLAGS_ALLOC);
>> vkms_config_connector->type = DRM_MODE_CONNECTOR_VIRTUAL;
>> vkms_config_connector->status = connector_status_unknown;
>> + vkms_config_connector->edid_blob_len = 0;
>>
>> return vkms_config_connector;
>> }
>> diff --git a/drivers/gpu/drm/vkms/vkms_config.h b/drivers/gpu/drm/vkms/vkms_config.h
>> index bba56c9d8aeceac97a4339ef42ab663c5dc54e65..1220b16f6c98d1ebb0ae55d662a84fe25e1a6a02 100644
>> --- a/drivers/gpu/drm/vkms/vkms_config.h
>> +++ b/drivers/gpu/drm/vkms/vkms_config.h
>> @@ -112,6 +112,8 @@ struct vkms_config_connector {
>> struct xarray possible_encoders;
>> int type;
>> enum drm_connector_status status;
>> + char edid_blob[PAGE_SIZE];
>> + int edid_blob_len;
>>
>> /* Internal usage */
>> struct drm_connector *connector;
>> diff --git a/drivers/gpu/drm/vkms/vkms_output.c b/drivers/gpu/drm/vkms/vkms_output.c
>> index fc6a0cdade0739b94820ed4e0924cf355137fe79..56590afb33d75465971d10a282040690840cdbee 100644
>> --- a/drivers/gpu/drm/vkms/vkms_output.c
>> +++ b/drivers/gpu/drm/vkms/vkms_output.c
>> @@ -31,13 +31,44 @@ static const struct drm_connector_funcs vkms_connector_funcs = {
>> .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
>> };
>>
>> +static int vkms_connector_read_block(void *context, u8 *buf, unsigned int block, size_t len)
>> +{
>> + struct vkms_config_connector *config = context;
>> +
>> + if (block * len + len > config->edid_blob_len)
>
>The parameters to the read block function are a bit weird for historical
>reasons. The start offset is indicated by block number, length by
>len. The start byte offset is thus block * EDID_LENGTH! There's no
>smaller granularity for start offset. However len can be < EDID_LENGTH!
>
>So the above should be (block * EDID_LENGTH + len > edid_blob_len)
>
>> + return 1;
>> + memcpy(buf, &config->edid_blob[block * len], len);
>
>And this should be &config->edid_blob[block * EDID_LENGTH].
>
>(Your patch would work, but just by coincidence due to the way the read
>block function is currently called.)
Thanks for those clarifications!
>> + return 0;
>> +}
>> +
>> static int vkms_conn_get_modes(struct drm_connector *connector)
>> {
>> + const struct drm_edid *drm_edid = NULL;
>> int count;
>> + struct vkms_config_connector *connector_cfg;
>> + struct vkms_device *vkmsdev = drm_device_to_vkms_device(connector->dev);
>> + struct vkms_config_connector *context = NULL;
>> +
>> + list_for_each_entry(connector_cfg, &vkmsdev->config->connectors, link) {
>> + if (connector_cfg->connector == connector) {
>> + context = connector_cfg;
>> + break;
>> + }
>> + }
>> + if (context)
>> + drm_edid = drm_edid_read_custom(connector, vkms_connector_read_block, context);
>
>Thanks for using drm_edid_read_custom() for this btw!
>
>> +
>> + /*
>> + * Unconditionally update the connector. If the EDID was read
>> + * successfully, fill in the connector information derived from the
>> + * EDID. Otherwise, if the EDID is NULL, clear the connector
>> + * information.
>> + */
>> + drm_edid_connector_update(connector, drm_edid);
>> +
>> + count = drm_edid_connector_add_modes(connector);
>>
>> - /* Use the default modes list from DRM */
>> - count = drm_add_modes_noedid(connector, XRES_MAX, YRES_MAX);
>> - drm_set_preferred_mode(connector, XRES_DEF, YRES_DEF);
>
>I don't really know anything about your use case, but don't you want to
>fall back to the above for drm_edid == NULL? *shrug*
You are right, I will probably fallback to noedid version, at least for VIRTUAL connectors.
Or maybe I will add something in VKMS configuration to use "empty edid", "default modes_noedid" or "custom_edid".
This way you will be able to test all the scenarios for your userspace.
Thanks for your review,
Louis Chauvet
>BR,
>Jani.
>
>> + drm_edid_free(drm_edid);
>>
>> return count;
>> }
>
I didn't see a `drm_connector_attach_edid_property` call in this series. Did you forget this? Virtual connectors don't have this property by default. Ian,
Le 22 novembre 2024 21:28:00 UTC, Ian Forbes <ian.forbes@broadcom.com> a écrit : >I didn't see a `drm_connector_attach_edid_property` call in this >series. Did you forget this? Virtual connectors don't have this >property by default. Hello Ian, You are right; I did not call this function. As mainly tested with the DP connector type, I never had any issue. I need to check if calling `drm_edid_connector_update` fails if the EDID property does not exist. Thanks, Louis Chauvet >Ian,
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