Re: [PATCH v2 7/8] drm/mediatek: Add programming flow for unsupported subsys ID hardware

[CK Hu (胡俊光)]

On Wed, 2024-12-11 at 11:46 +0800, CK Hu wrote:
> Hi, Jason:
> 
> On Wed, 2024-12-11 at 11:22 +0800, Jason-JH.Lin wrote:
> > To support hardware without subsys IDs on new SoCs, add a programming
> > flow that checks whether the subsys ID is valid. If the subsys ID is
> > invalid, the flow will call 2 alternative CMDQ APIs:
> > cmdq_pkt_assign() and cmdq_pkt_write_s_value() to achieve the same
> > functionality.
> > 
> > Signed-off-by: Jason-JH.Lin <jason-jh.lin@xxxxxxxxxxxx>
> > ---
> >  drivers/gpu/drm/mediatek/mtk_ddp_comp.c | 34 ++++++++++++++++++++-----
> >  1 file changed, 28 insertions(+), 6 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/mediatek/mtk_ddp_comp.c b/drivers/gpu/drm/mediatek/mtk_ddp_comp.c
> > index edc6417639e6..0792c895526f 100644
> > --- a/drivers/gpu/drm/mediatek/mtk_ddp_comp.c
> > +++ b/drivers/gpu/drm/mediatek/mtk_ddp_comp.c
> > @@ -66,14 +66,38 @@ struct mtk_ddp_comp_dev {
> >  	struct cmdq_client_reg cmdq_reg;
> >  };
> >  
> > +#if IS_REACHABLE(CONFIG_MTK_CMDQ)
> > +static void mtk_ddp_write_cmdq_pkt(struct cmdq_pkt *cmdq_pkt, struct cmdq_client_reg *cmdq_reg,
> > +				   unsigned int offset, unsigned int value, unsigned int mask)
> 
> Drop this function.

Sorry, it seems cmdq_subsys_is_valid() is used to check the SoC support new API or not.
But I would try to find out a way not to always check using new API or not.

Regards,
CK

> 
> > +{
> > +	struct cmdq_client *cl = (struct cmdq_client *)cmdq_pkt->cl;
> > +
> > +	offset += cmdq_reg->offset;
> > +
> > +	if (cmdq_subsys_is_valid(cl->chan, cmdq_reg->subsys)) {
> > +		if (mask == GENMASK(31, 0))
> > +			cmdq_pkt_write(cmdq_pkt, cmdq_reg->subsys, offset, value);
> > +		else
> > +			cmdq_pkt_write_mask(cmdq_pkt, cmdq_reg->subsys, offset, value, mask);
> > +	} else {
> > +		/* only MMIO access, no need to check mminfro_offset */
> > +		cmdq_pkt_assign(cmdq_pkt, 0, CMDQ_ADDR_HIGH(cmdq_reg->pa_base));
> > +		if (mask == GENMASK(31, 0))
> > +			cmdq_pkt_write_s_value(cmdq_pkt, 0, CMDQ_ADDR_LOW(offset), value);
> > +		else
> > +			cmdq_pkt_write_s_mask_value(cmdq_pkt, 0, CMDQ_ADDR_LOW(offset),
> > +						    value, mask);
> > +	}
> > +}
> > +#endif
> > +
> >  void mtk_ddp_write(struct cmdq_pkt *cmdq_pkt, unsigned int value,
> >  		   struct cmdq_client_reg *cmdq_reg, void __iomem *regs,
> >  		   unsigned int offset)
> >  {
> >  #if IS_REACHABLE(CONFIG_MTK_CMDQ)
> >  	if (cmdq_pkt)
> > -		cmdq_pkt_write(cmdq_pkt, cmdq_reg->subsys,
> > -			       cmdq_reg->offset + offset, value);
> > +		mtk_ddp_write_cmdq_pkt(cmdq_pkt, cmdq_reg, offset, value, GENMASK(31, 0));
> 
> /* only MMIO access, no need to check mminfro_offset */
> cmdq_pkt_assign(cmdq_pkt, CMDQ_XXXREG_0, CMDQ_ADDR_HIGH(cmdq_reg->pa_base));
> cmdq_pkt_write_s_value(cmdq_pkt, CMDQ_XXXREG_0, CMDQ_ADDR_LOW(offset), value);
> 
> >  	else
> >  #endif
> >  		writel(value, regs + offset);
> > @@ -85,8 +109,7 @@ void mtk_ddp_write_relaxed(struct cmdq_pkt *cmdq_pkt, unsigned int value,
> >  {
> >  #if IS_REACHABLE(CONFIG_MTK_CMDQ)
> >  	if (cmdq_pkt)
> > -		cmdq_pkt_write(cmdq_pkt, cmdq_reg->subsys,
> > -			       cmdq_reg->offset + offset, value);
> > +		mtk_ddp_write_cmdq_pkt(cmdq_pkt, cmdq_reg, offset, value, GENMASK(31, 0));
> 
> /* only MMIO access, no need to check mminfro_offset */
> cmdq_pkt_assign(cmdq_pkt, CMDQ_XXXREG_0, CMDQ_ADDR_HIGH(cmdq_reg->pa_base));
> cmdq_pkt_write_s_value(cmdq_pkt, CMDQ_XXXREG_0, CMDQ_ADDR_LOW(offset), value);
> 
> >  	else
> >  #endif
> >  		writel_relaxed(value, regs + offset);
> > @@ -98,8 +121,7 @@ void mtk_ddp_write_mask(struct cmdq_pkt *cmdq_pkt, unsigned int value,
> >  {
> >  #if IS_REACHABLE(CONFIG_MTK_CMDQ)
> >  	if (cmdq_pkt) {
> > -		cmdq_pkt_write_mask(cmdq_pkt, cmdq_reg->subsys,
> > -				    cmdq_reg->offset + offset, value, mask);
> > +		mtk_ddp_write_cmdq_pkt(cmdq_pkt, cmdq_reg, offset, value, mask);
> 
> /* only MMIO access, no need to check mminfro_offset */
> cmdq_pkt_assign(cmdq_pkt, CMDQ_XXXREG_0, CMDQ_ADDR_HIGH(cmdq_reg->pa_base));
> cmdq_pkt_write_s_mask_value(cmdq_pkt, CMDQ_XXXREG_0, CMDQ_ADDR_LOW(offset),
> 			    value, mask);
> 
> CMDQ_XXXREG_0 is defined in cmdq header file.
> 
> Regards,
> CK
> 
> >  	} else {
> >  #endif
> >  		u32 tmp = readl(regs + offset);
>