On Mon, Jun 06, 2022 at 12:47:13PM +0100, carsten.haitzler@xxxxxxxxxxxx wrote: > From: Carsten Haitzler <carsten.haitzler@xxxxxxx> > > If something has already set up the DPU before the komeda driver comes > up, it will fail to init because it was just writing to the SRST bit in > the GCU control register and ignoring others. This resulted in TBU > bringup stalling and init failing. By writing completely we also set the > mode back to 0 (inactive) too and thus TBU bringup works. This is a rather large hammer, tbh. I would like to see if there is a better way of handling the handover from EFIFB that this patch is trying to fix, but I lack an usable plaform for that. It will generate a flicker at module load time, but if users of Morello are happy with that, then Acked-by: Liviu Dudau <liviu.dudau@xxxxxxx> Best regards, Liviu > > Signed-off-by: Carsten Haitzler <carsten.haitzler@xxxxxxx> > --- > drivers/gpu/drm/arm/display/komeda/d71/d71_dev.c | 3 +-- > 1 file changed, 1 insertion(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/arm/display/komeda/d71/d71_dev.c b/drivers/gpu/drm/arm/display/komeda/d71/d71_dev.c > index 00fa56c29b3e..39618c1a4c81 100644 > --- a/drivers/gpu/drm/arm/display/komeda/d71/d71_dev.c > +++ b/drivers/gpu/drm/arm/display/komeda/d71/d71_dev.c > @@ -309,8 +309,7 @@ static int d71_reset(struct d71_dev *d71) > u32 __iomem *gcu = d71->gcu_addr; > int ret; > > - malidp_write32_mask(gcu, BLK_CONTROL, > - GCU_CONTROL_SRST, GCU_CONTROL_SRST); > + malidp_write32(gcu, BLK_CONTROL, GCU_CONTROL_SRST); > > ret = dp_wait_cond(!(malidp_read32(gcu, BLK_CONTROL) & GCU_CONTROL_SRST), > 100, 1000, 10000); > -- > 2.32.0 > -- ==================== | I would like to | | fix the world, | | but they're not | | giving me the | \ source code! / --------------- ¯\_(ツ)_/¯