On 10/02/16 21:52, Fabio Estevam wrote: > Hi Tomi, > > On Fri, Jan 29, 2016 at 10:20 AM, Tomi Valkeinen <tomi.valkeinen@xxxxxx> wrote: >> >> >> On 19/01/16 15:10, Fabio Estevam wrote: >>> From: Fabio Estevam <fabio.estevam@xxxxxxx> >>> >>> Currently when we boot the kernel on a mx25pdk the LCDC controller >>> does not show the Linux logo on boot. >>> >>> This problem is well explained by Sascha Hauer: >>> >>> "Unfortunately this LCD controller does not have an enable bit. The >>> controller starts directly when the clocks are enabled. If the clocks >>> are enabled when the controller is not yet programmed with proper >>> register values then it just goes into some undefined state. What I >>> suspect is that the clocks already were enabled before driver probe, >>> presumably by the bootloader, so the controller is already in undefined >>> state when entering Linux. Now by dis/enabling the ipg clock you >>> effectively reset the controller. Since you have programmed it with >>> valid register values in the mean time it starts working after this >>> reset." >>> >>> So do as suggested and force a reset of the LCDC hardware by >>> enabling and disabling the IPG clock. >>> >>> With this change the Linux logo can be seen on boot on a mx25pdk. >>> >>> Signed-off-by: Fabio Estevam <fabio.estevam@xxxxxxx> >>> --- >>> drivers/video/fbdev/imxfb.c | 15 +++++++++++++++ >>> 1 file changed, 15 insertions(+) >> >> Thanks. Queued for 4.5 fixes. > > Still don't see this one applied in Linus nor linux-next tree yet. I've been a bit preoccupied, but I hope I get to send the pull request today. Tomi
Attachment:
signature.asc
Description: OpenPGP digital signature
