[PATCH] drm: Fix EDID firmware load on resume
Matthieu CHARETTE
matthieu.charette at gmail.com
Mon Aug 8 15:17:48 UTC 2022
Sorry, What do you mean?
Matthieu
On Tue, Aug 2 2022 at 05:29:12 PM +0300, Jani Nikula
<jani.nikula at linux.intel.com> wrote:
> On Wed, 27 Jul 2022, Matthieu CHARETTE <matthieu.charette at gmail.com>
> wrote:
>> Loading an EDID using drm.edid_firmware parameter makes resume to
>> fail
>> after firmware cache is being cleaned. This is because edid_load()
>> use a
>> temporary device to request the firmware. This cause the EDID
>> firmware
>> not to be cached from suspend. And, requesting the EDID firmware
>> return
>> an error during resume.
>> So the request_firmware() call should use a permanent device for
>> each
>> connector. Also, we should cache the EDID even if no monitor is
>> connected, in case it's plugged while suspended.
>
> AFAICT this breaks changing drm.edid_firmware runtime.
>
> BR,
> Jani.
>
>>
>> Link: https://gitlab.freedesktop.org/drm/amd/-/issues/2061
>> Signed-off-by: Matthieu CHARETTE <matthieu.charette at gmail.com>
>> ---
>> drivers/gpu/drm/drm_connector.c | 9 ++++
>> drivers/gpu/drm/drm_edid_load.c | 81
>> ++++++++++++++++++++++++++++-----
>> include/drm/drm_connector.h | 12 +++++
>> include/drm/drm_edid.h | 3 ++
>> 4 files changed, 94 insertions(+), 11 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/drm_connector.c
>> b/drivers/gpu/drm/drm_connector.c
>> index 1c48d162c77e..e8819ebf1c4b 100644
>> --- a/drivers/gpu/drm/drm_connector.c
>> +++ b/drivers/gpu/drm/drm_connector.c
>> @@ -31,6 +31,7 @@
>> #include <drm/drm_privacy_screen_consumer.h>
>> #include <drm/drm_sysfs.h>
>>
>> +#include <linux/platform_device.h>
>> #include <linux/uaccess.h>
>>
>> #include "drm_crtc_internal.h"
>> @@ -289,6 +290,9 @@ int drm_connector_init(struct drm_device *dev,
>>
>> drm_connector_get_cmdline_mode(connector);
>>
>> + connector->edid_load_pdev = NULL;
>> + drm_cache_edid_firmware(connector);
>> +
>> /* We should add connectors at the end to avoid upsetting the
>> connector
>> * index too much.
>> */
>> @@ -473,6 +477,11 @@ void drm_connector_cleanup(struct
>> drm_connector *connector)
>> connector->tile_group = NULL;
>> }
>>
>> + if (connector->edid_load_pdev) {
>> + platform_device_unregister(connector->edid_load_pdev);
>> + connector->edid_load_pdev = NULL;
>> + }
>> +
>> list_for_each_entry_safe(mode, t, &connector->probed_modes, head)
>> drm_mode_remove(connector, mode);
>>
>> diff --git a/drivers/gpu/drm/drm_edid_load.c
>> b/drivers/gpu/drm/drm_edid_load.c
>> index 37d8ba3ddb46..5a82be9917ec 100644
>> --- a/drivers/gpu/drm/drm_edid_load.c
>> +++ b/drivers/gpu/drm/drm_edid_load.c
>> @@ -167,6 +167,19 @@ static int edid_size(const u8 *edid, int
>> data_size)
>> return (edid[0x7e] + 1) * EDID_LENGTH;
>> }
>>
>> +static struct platform_device *edid_pdev(const char
>> *connector_name)
>> +{
>> + struct platform_device *pdev =
>> platform_device_register_simple(connector_name, -1, NULL, 0);
>> +
>> + if (IS_ERR(pdev)) {
>> + DRM_ERROR("Failed to register EDID firmware platform device "
>> + "for connector \"%s\"\n", connector_name);
>> + return ERR_CAST(pdev);
>> + }
>> +
>> + return pdev;
>> +}
>> +
>> static void *edid_load(struct drm_connector *connector, const char
>> *name,
>> const char *connector_name)
>> {
>> @@ -182,18 +195,17 @@ static void *edid_load(struct drm_connector
>> *connector, const char *name,
>> fwdata = generic_edid[builtin];
>> fwsize = sizeof(generic_edid[builtin]);
>> } else {
>> - struct platform_device *pdev;
>> + struct platform_device *pdev = connector->edid_load_pdev;
>> int err;
>>
>> - pdev = platform_device_register_simple(connector_name, -1, NULL,
>> 0);
>> - if (IS_ERR(pdev)) {
>> - DRM_ERROR("Failed to register EDID firmware platform device "
>> - "for connector \"%s\"\n", connector_name);
>> - return ERR_CAST(pdev);
>> + if (WARN_ON(!pdev)) {
>> + pdev = edid_pdev(connector_name);
>> + if (IS_ERR(pdev))
>> + return ERR_CAST(pdev);
>> + connector->edid_load_pdev = pdev;
>> }
>>
>> err = request_firmware(&fw, name, &pdev->dev);
>> - platform_device_unregister(pdev);
>> if (err) {
>> DRM_ERROR("Requesting EDID firmware \"%s\" failed (err=%d)\n",
>> name, err);
>> @@ -263,11 +275,9 @@ static void *edid_load(struct drm_connector
>> *connector, const char *name,
>> return edid;
>> }
>>
>> -struct edid *drm_load_edid_firmware(struct drm_connector
>> *connector)
>> +static char *edid_name(const char *connector_name)
>> {
>> - const char *connector_name = connector->name;
>> char *edidname, *last, *colon, *fwstr, *edidstr, *fallback = NULL;
>> - struct edid *edid;
>>
>> if (edid_firmware[0] == '\0')
>> return ERR_PTR(-ENOENT);
>> @@ -310,8 +320,57 @@ struct edid *drm_load_edid_firmware(struct
>> drm_connector *connector)
>> if (*last == '\n')
>> *last = '\0';
>>
>> - edid = edid_load(connector, edidname, connector_name);
>> + edidname = kstrdup(edidname, GFP_KERNEL);
>> + if (!edidname) {
>> + kfree(fwstr);
>> + return ERR_PTR(-ENOMEM);
>> + }
>> +
>> kfree(fwstr);
>> + return edidname;
>> +}
>> +
>> +void drm_cache_edid_firmware(struct drm_connector *connector)
>> +{
>> + const char *connector_name = connector->name;
>> + const char *edidname = edid_name(connector_name);
>> + struct platform_device *pdev;
>> + int err;
>> +
>> + if (IS_ERR(edidname))
>> + return;
>> +
>> + if (match_string(generic_edid_name, GENERIC_EDIDS, edidname) >=
>> 0) {
>> + kfree(edidname);
>> + return;
>> + }
>> +
>> + pdev = edid_pdev(connector_name);
>> + if (IS_ERR(pdev)) {
>> + kfree(edidname);
>> + return;
>> + }
>> + connector->edid_load_pdev = pdev;
>> +
>> + err = firmware_request_cache(&pdev->dev, edidname);
>> + if (err)
>> + DRM_ERROR("Requesting EDID firmware cache \"%s\" failed
>> (err=%d)\n",
>> + edidname, err);
>> +
>> + kfree(edidname);
>> +}
>> +
>> +struct edid *drm_load_edid_firmware(struct drm_connector
>> *connector)
>> +{
>> + const char *connector_name = connector->name;
>> + const char *edidname = edid_name(connector_name);
>> + struct edid *edid;
>> +
>> + if (IS_ERR(edidname))
>> + return ERR_CAST(edidname);
>> +
>> + edid = edid_load(connector, edidname, connector_name);
>> + kfree(edidname);
>>
>> return edid;
>> }
>> diff --git a/include/drm/drm_connector.h
>> b/include/drm/drm_connector.h
>> index 3ac4bf87f257..47c84741517e 100644
>> --- a/include/drm/drm_connector.h
>> +++ b/include/drm/drm_connector.h
>> @@ -1573,6 +1573,18 @@ struct drm_connector {
>> */
>> struct i2c_adapter *ddc;
>>
>> + /**
>> + * @edid_load_pdev: Platform device for loading EDID via firmware.
>> + *
>> + * The platform device is registered in drm_connector_init() in
>> case a
>> + * custom EDID firmware is used with `edid_firmware` parameter.
>> Otherwise,
>> + * it is set to NULL.
>> + *
>> + * Platform device is unregistered in drm_connector_cleanup() if
>> it
>> + * is not NULL.
>> + */
>> + struct platform_device *edid_load_pdev;
>> +
>> /**
>> * @null_edid_counter: track sinks that give us all zeros for the
>> EDID.
>> * Needed to workaround some HW bugs where we get all 0s
>> diff --git a/include/drm/drm_edid.h b/include/drm/drm_edid.h
>> index b2756753370b..e907c928a35d 100644
>> --- a/include/drm/drm_edid.h
>> +++ b/include/drm/drm_edid.h
>> @@ -378,10 +378,13 @@ int drm_av_sync_delay(struct drm_connector
>> *connector,
>> const struct drm_display_mode *mode);
>>
>> #ifdef CONFIG_DRM_LOAD_EDID_FIRMWARE
>> +void drm_cache_edid_firmware(struct drm_connector *connector);
>> struct edid *drm_load_edid_firmware(struct drm_connector
>> *connector);
>> int __drm_set_edid_firmware_path(const char *path);
>> int __drm_get_edid_firmware_path(char *buf, size_t bufsize);
>> #else
>> +inline void
>> +drm_cache_edid_firmware(struct drm_connector *connector);
>> static inline struct edid *
>> drm_load_edid_firmware(struct drm_connector *connector)
>> {
>
> --
> Jani Nikula, Intel Open Source Graphics Center
More information about the dri-devel
mailing list