Re: [RFC 7/9] drm: rcar-du: group: Enable CMM unit

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

Hi Jacopo,

Thank you for the patch.

On Wed, May 08, 2019 at 07:34:26PM +0200, Jacopo Mondi wrote:
> Enable the CMM units present in the group through the display unit
> extensional function control group register DEFR7.
> 
> Signed-off-by: Jacopo Mondi <jacopo+renesas@jmondi.org>
> ---
>  drivers/gpu/drm/rcar-du/rcar_du_group.c | 8 ++++++++
>  drivers/gpu/drm/rcar-du/rcar_du_regs.h  | 5 +++++
>  2 files changed, 13 insertions(+)
> 
> diff --git a/drivers/gpu/drm/rcar-du/rcar_du_group.c b/drivers/gpu/drm/rcar-du/rcar_du_group.c
> index 9eee47969e77..ce25e41b04bc 100644
> --- a/drivers/gpu/drm/rcar-du/rcar_du_group.c
> +++ b/drivers/gpu/drm/rcar-du/rcar_du_group.c
> @@ -147,6 +147,14 @@ static void rcar_du_group_setup(struct rcar_du_group *rgrp)
>  
>  	rcar_du_group_setup_pins(rgrp);
>  
> +	if (rgrp->cmms_mask) {
> +		u32 defr7 = DEFR7_CODE;
> +		defr7 |= rgrp->cmms_mask & BIT(1) ? DEFR7_CMME1 : 0;
> +		defr7 |= rgrp->cmms_mask & BIT(0) ? DEFR7_CMME0 : 0;
> +
> +		rcar_du_group_write(rgrp, DEFR7, defr7);
> +	}
> +

I would guard this with the CMM feature bit instead of cmms_mask, in
order to write the register with 0 if CMMs are not supported, just in
case it maye have been written to another value by the boot loader (or
before a warm reboot).

Apart from that,

Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

>  	if (rcdu->info->gen >= 2) {
>  		rcar_du_group_setup_defr8(rgrp);
>  		rcar_du_group_setup_didsr(rgrp);
> diff --git a/drivers/gpu/drm/rcar-du/rcar_du_regs.h b/drivers/gpu/drm/rcar-du/rcar_du_regs.h
> index bc87f080b170..fb9964949368 100644
> --- a/drivers/gpu/drm/rcar-du/rcar_du_regs.h
> +++ b/drivers/gpu/drm/rcar-du/rcar_du_regs.h
> @@ -197,6 +197,11 @@
>  #define DEFR6_MLOS1		(1 << 2)
>  #define DEFR6_DEFAULT		(DEFR6_CODE | DEFR6_TCNE1)
>  
> +#define DEFR7			0x000ec
> +#define DEFR7_CODE		(0x7779 << 16)
> +#define DEFR7_CMME1		BIT(6)
> +#define DEFR7_CMME0		BIT(4)
> +
>  /* -----------------------------------------------------------------------------
>   * R8A7790-only Control Registers
>   */

-- 
Regards,

Laurent Pinchart