Hi Linus.
On Sun, Jun 14, 2020 at 12:30:26AM +0200, Linus Walleij wrote:
The following bug appeared in the MCDE driver/display initialization during the recent merge window.
First the place we call drm_fbdev_generic_setup() in the wrong place: this needs to be called AFTER calling drm_dev_register() else we get this splat:
------------[ cut here ]------------ WARNING: CPU: 0 PID: 1 at ../drivers/gpu/drm/drm_fb_helper.c:2198 drm_fbdev_generic_setup+0x164/0x1a8 mcde a0350000.mcde: Device has not been registered. Modules linked in: Hardware name: ST-Ericsson Ux5x0 platform (Device Tree Support) [<c010e704>] (unwind_backtrace) from [<c010a86c>] (show_stack+0x10/0x14) [<c010a86c>] (show_stack) from [<c0414f38>] (dump_stack+0x9c/0xb0) [<c0414f38>] (dump_stack) from [<c0121c8c>] (__warn+0xb8/0xd0) [<c0121c8c>] (__warn) from [<c0121d18>] (warn_slowpath_fmt+0x74/0xb8) [<c0121d18>] (warn_slowpath_fmt) from [<c04b154c>] (drm_fbdev_generic_setup+0x164/0x1a8) [<c04b154c>] (drm_fbdev_generic_setup) from [<c04ed278>] (mcde_drm_bind+0xc4/0x160) [<c04ed278>] (mcde_drm_bind) from [<c04f06b8>] (try_to_bring_up_master+0x15c/0x1a4) (...)
Signed-off-by: Linus Walleij linus.walleij@linaro.org
Yup, this is the right way to do it.
Reviewed-by: Sam Ravnborg sam@ravnborg.org
One small thing to consider, see below. But for another patch.
drivers/gpu/drm/mcde/mcde_drv.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/mcde/mcde_drv.c b/drivers/gpu/drm/mcde/mcde_drv.c index 84f3e2dbd77b..80082d6dce3a 100644 --- a/drivers/gpu/drm/mcde/mcde_drv.c +++ b/drivers/gpu/drm/mcde/mcde_drv.c @@ -209,7 +209,6 @@ static int mcde_modeset_init(struct drm_device *drm)
drm_mode_config_reset(drm); drm_kms_helper_poll_init(drm);
drm_fbdev_generic_setup(drm, 32);
return 0;
} @@ -264,6 +263,8 @@ static int mcde_drm_bind(struct device *dev) if (ret < 0) goto unbind;
- drm_fbdev_generic_setup(drm, 32);
Consider using mode_config.preferred_depth, then you can pass 0 here.
- return 0;
unbind:
2.26.2
dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel