[PATCH] drm: Fix EDID firmware load on resume
Jani Nikula
jani.nikula at linux.intel.com
Mon Aug 8 17:19:01 UTC 2022
On Mon, 08 Aug 2022, Matthieu CHARETTE <matthieu.charette at gmail.com> wrote:
> Sorry, What do you mean?
You cache with one name at connector init time, but the name specified
using drm.edid_firmware may be changed whenever, to cause the next EDID
read to use a different EDID firmware.
BR,
Jani.
>
> 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
>> <mailto: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
>>> <mailto: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
>
--
Jani Nikula, Intel Open Source Graphics Center
More information about the dri-devel
mailing list