Re: [PATCH v2 2/4] drm/mediatek: Add support for mediatek SOC MT2712

From: Stu Hsieh
Date: Thu May 24 2018 - 03:47:49 EST


Hi CK,

On Thu, 2018-05-24 at 09:26 +0800, CK Hu wrote:
> Hi, Stu:
>
> On Wed, 2018-05-23 at 17:28 +0800, Stu Hsieh wrote:
> > On Wed, 2018-05-23 at 13:23 +0800, CK Hu wrote:
> > > Hi, Stu:
> > >
> > > I've some inline comment.
> > >
> > > On Wed, 2018-05-23 at 10:25 +0800, Stu Hsieh wrote:
> > > > This patch add support for the Mediatek MT2712 DISP subsystem.
> > > > There are two OVL engine and three disp output in MT2712.
> > > >
> > > > Signed-off-by: Stu Hsieh <stu.hsieh@xxxxxxxxxxxx>
> > > > ---
> > > > drivers/gpu/drm/mediatek/mtk_drm_ddp.c | 50 +++++++++++++++++++++++++++--
> > > > drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c | 8 +++--
> > > > drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h | 7 ++--
> > > > drivers/gpu/drm/mediatek/mtk_drm_drv.c | 47 +++++++++++++++++++++++++--
> > > > drivers/gpu/drm/mediatek/mtk_drm_drv.h | 7 ++--
> > > > 5 files changed, 108 insertions(+), 11 deletions(-)
> > > >
> > > > +#define MT2712_MUTEX_MOD_DISP_AAL0 BIT(20)
> > > > +#define MT2712_MUTEX_MOD_DISP_UFOE BIT(22)
> > > > +#define MT2712_MUTEX_MOD_DISP_PWM0 BIT(23)
> > > > +#define MT2712_MUTEX_MOD_DISP_PWM1 BIT(24)
> > > > +#define MT2712_MUTEX_MOD_DISP_PWM2 BIT(10)
> > > > +#define MT2712_MUTEX_MOD_DISP_OD0 BIT(25)
> > > > +/* modules more than 32, add BIT(31) when using DISP_REG_MUTEX_MOD2 bit */
> > > > +#define MT2712_MUTEX_MOD2_DISP_AAL1 (BIT(1) | BIT(31))
> > >
> > > I think a better definition is
> > >
> > > #define MT2712_MUTEX_MOD2_DISP_AAL1 BIT(33)
> > >
> > > when you need to access this register,
> > >
> > > if (ddp->mutex_mod[id] < BIT(32)) {
> > > offset = DISP_REG_MUTEX_MOD(mutex->id);
> > > reg = readl_relaxed(ddp->regs + offset);
> > > reg |= ddp->mutex_mod[id];
> > > writel_relaxed(reg, ddp->regs + offset);
> > > } else {
> > > offset = DISP_REG_MUTEX_MOD2(mutex->id);
> > > reg = readl_relaxed(ddp->regs + offset);
> > > reg |= (ddp->mutex_mod[id] >> 32);
> > > writel_relaxed(reg, ddp->regs + offset);
> > > }
> > >
> > > because DISP_REG_MUTEX_MOD BIT(31) could be used for some module.
> >
> > This modification is workable, but result some build warning like
> > following:
> > 1. #define BIT(nr) (1UL << (nr)) in include/linux/bitops.h
> > 2. [DDP_COMPONENT_AAL1] = MT2712_MUTEX_MOD2_DISP_AAL1,
> > => we need to modify the definition about "static const unsigned int
> > mt2712_mutex_mod"
> >
>
> Currently, mutex_mod is a bitwise definition. I think it could be
> changed to index definition such as
>
>
> #define MT2712_MUTEX_MOD_DISP_PWM2 10
> #define MT2712_MUTEX_MOD_DISP_OD0 25
> #define MT2712_MUTEX_MOD2_DISP_AAL1 33
>
> when you need to access this register,
>
> if (ddp->mutex_mod[id] < 32) {
> offset = DISP_REG_MUTEX_MOD(mutex->id);
> reg = readl_relaxed(ddp->regs + offset);
> reg |= 1 << ddp->mutex_mod[id];
> writel_relaxed(reg, ddp->regs + offset);
> } else {
> offset = DISP_REG_MUTEX_MOD2(mutex->id);
> reg = readl_relaxed(ddp->regs + offset);
> reg |= 1 << (ddp->mutex_mod[id] - 32);
> writel_relaxed(reg, ddp->regs + offset);
> }
>
> Regards,
> CK

This modification has no build warning.
I would also change the definition about 2701 and 8173 from bitwise to
index.

Regards,
Stu

>
> > > > +#define MT2712_MUTEX_MOD2_DISP_OD1 (BIT(2) | BIT(31))
> > > > +
> > > > #define MT2701_MUTEX_MOD_DISP_OVL BIT(3)
> > > > #define MT2701_MUTEX_MOD_DISP_WDMA BIT(6)
> > > > #define MT2701_MUTEX_MOD_DISP_COLOR BIT(7)
> > > > @@ -74,6 +96,7 @@
> > > >
> > > >
> > >
> > >
> >
> >
>
>