On Tue, May 03, 2022 at 09:15:40AM +0200, Javier Martinez Canillas wrote:
Indicate to fbdev subsystem that the registered framebuffer is provided by the system firmware, so that it can handle accordingly. For example, would unregister the FB devices if asked to remove the conflicting framebuffers.
Add a new DRM_FB_FW field to drm_fbdev_generic_setup() options parameter. Drivers can use this to indicate the FB helper initialization that the FB registered is provided by the firmware, so it can be configured as such.
Suggested-by: Thomas Zimmermann tzimmermann@suse.de Signed-off-by: Javier Martinez Canillas javierm@redhat.com Reviewed-by: Thomas Zimmermann tzimmermann@suse.de Reviewed-by: Laurent Pinchart laurent.pinchart@ideasonboard.com
Changes in v3:
- Drop the firmware local variable (Laurent Pinchart).
- Use DRM_FB_OPTION() since DRM_FB_SET_OPTION() got renamed (kernel test robot).
Just for the record what I brought up on irc already:
FBINFO_MISC_FIRMWARE is purely an internal flag with no uapi impact, and it's only to control whether we nuke this from remove_conflicting_framebuffer or not. Since simpledrm only ever binds against sysfb I think it'd be cleaner to only rely on that, and relegate that entire FBINFO_MISC_FIRMWARE misc hack to the fbdev dungeons and let it quietly wither away there.
Also I'm not a huge fan of these midlayer flags in general :-) -Daniel
drivers/gpu/drm/drm_fb_helper.c | 8 ++++++++ drivers/gpu/drm/tiny/simpledrm.c | 2 +- include/drm/drm_fb_helper.h | 10 ++++++++++ 3 files changed, 19 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c index 52042ba1e4cf..28b21858b726 100644 --- a/drivers/gpu/drm/drm_fb_helper.c +++ b/drivers/gpu/drm/drm_fb_helper.c @@ -1891,6 +1891,10 @@ __drm_fb_helper_initial_config_and_unlock(struct drm_fb_helper *fb_helper, /* don't leak any physical addresses to userspace */ info->flags |= FBINFO_HIDE_SMEM_START;
- /* Indicate that the framebuffer is provided by the firmware */
- if (fb_helper->firmware)
info->flags |= FBINFO_MISC_FIRMWARE;- /* Need to drop locks to avoid recursive deadlock in
- register_framebuffer. This is ok because the only thing left to do is
- register the fbdev emulation instance in kernel_fb_helper_list. */
@@ -2512,6 +2516,8 @@ static const struct drm_client_funcs drm_fbdev_client_funcs = {
- DRM_FB_BPP: bits per pixel for the device. If the field is not set,
- @dev->mode_config.preferred_depth is used instead.
- DRM_FB_FW: if the framebuffer for the device is provided by the
- system firmware.
- This function sets up generic fbdev emulation for drivers that supports
- dumb buffers with a virtual address and that can be mmap'ed.
@@ -2569,6 +2575,8 @@ void drm_fbdev_generic_setup(struct drm_device *dev, const unsigned int options) if (!fb_helper->preferred_bpp) fb_helper->preferred_bpp = 32;
- fb_helper->firmware = DRM_FB_GET_OPTION(DRM_FB_FW, options);
- ret = drm_fbdev_client_hotplug(&fb_helper->client); if (ret) drm_dbg_kms(dev, "client hotplug ret=%d\n", ret);
diff --git a/drivers/gpu/drm/tiny/simpledrm.c b/drivers/gpu/drm/tiny/simpledrm.c index f5b8e864a5cd..f6f1c5e108b2 100644 --- a/drivers/gpu/drm/tiny/simpledrm.c +++ b/drivers/gpu/drm/tiny/simpledrm.c @@ -901,7 +901,7 @@ static int simpledrm_probe(struct platform_device *pdev) if (ret) return ret;
- drm_fbdev_generic_setup(dev, 0);
drm_fbdev_generic_setup(dev, DRM_FB_OPTION(DRM_FB_FW, 1));
return 0;
} diff --git a/include/drm/drm_fb_helper.h b/include/drm/drm_fb_helper.h index 5fc41cf0c987..5a17af423944 100644 --- a/include/drm/drm_fb_helper.h +++ b/include/drm/drm_fb_helper.h @@ -44,6 +44,7 @@ enum mode_set_atomic { };
#define DRM_FB_BPP_MASK GENMASK(7, 0) +#define DRM_FB_FW_MASK GENMASK(8, 8)
/* Using the GNU statement expression extension */ #define DRM_FB_OPTION(option, value) \ @@ -197,6 +198,15 @@ struct drm_fb_helper { * See also: @deferred_setup */ int preferred_bpp;
- /**
* @firmware:** Set if the driver indicates to the FB helper initialization that the* framebuffer for the device being registered is provided by firmware,* so that it can pass this on when registering the framebuffer device.*/- bool firmware;
};
static inline struct drm_fb_helper *
2.35.1