Re: [PATCH v1 07/12] soc: mediatek: cmdq: add write_s function

[Dennis-YC Hsieh]

Hi CK,

On Mon, 2019-11-25 at 10:08 +0800, CK Hu wrote:
> Hi, Dennis:
> 
> On Fri, 2019-11-22 at 18:11 +0800, Dennis-YC Hsieh wrote:
> > Hi CK,
> > 
> > On Fri, 2019-11-22 at 16:56 +0800, CK Hu wrote:
> > > Hi, Dennis:
> > > 
> > > On Thu, 2019-11-21 at 17:12 +0800, Dennis YC Hsieh wrote:
> > > > add write_s function in cmdq helper functions which
> > > > support large dma access.
> > > > 
> > > > Signed-off-by: Dennis YC Hsieh <dennis-yc.hsieh@xxxxxxxxxxxx>
> > > > ---
> > > >  drivers/soc/mediatek/mtk-cmdq-helper.c   |   34 ++++++++++++++++++++++++++++++
> > > >  include/linux/mailbox/mtk-cmdq-mailbox.h |    2 ++
> > > >  include/linux/soc/mediatek/mtk-cmdq.h    |   13 ++++++++++++
> > > >  3 files changed, 49 insertions(+)
> > > > 
> > > > diff --git a/drivers/soc/mediatek/mtk-cmdq-helper.c b/drivers/soc/mediatek/mtk-cmdq-helper.c
> > > > index d419e99..1b074a9 100644
> > > > --- a/drivers/soc/mediatek/mtk-cmdq-helper.c
> > > > +++ b/drivers/soc/mediatek/mtk-cmdq-helper.c
> > > > @@ -15,6 +15,9 @@
> > > >  #define CMDQ_EOC_CMD		((u64)((CMDQ_CODE_EOC << CMDQ_OP_CODE_SHIFT)) \
> > > >  				<< 32 | CMDQ_EOC_IRQ_EN)
> > > >  #define CMDQ_REG_TYPE		1
> > > > +#define CMDQ_ADDR_HIGH(addr)	((u32)(((addr) >> 16) & GENMASK(31, 0)))
> > > > +#define CMDQ_ADDR_LOW_BIT	BIT(1)
> > > > +#define CMDQ_ADDR_LOW(addr)	((u16)(addr) | CMDQ_ADDR_LOW_BIT)
> > > >  
> > > >  struct cmdq_instruction {
> > > >  	union {
> > > > @@ -224,6 +227,37 @@ int cmdq_pkt_write_mask(struct cmdq_pkt *pkt, u8 subsys,
> > > >  }
> > > >  EXPORT_SYMBOL(cmdq_pkt_write_mask);
> > > >  
> > > > +int cmdq_pkt_write_s(struct cmdq_pkt *pkt, dma_addr_t addr,
> > > > +		     u32 value, u32 mask)
> > > > +{
> > > > +	struct cmdq_instruction inst = { {0} };
> > > > +	int err;
> > > > +	const u16 dst_reg_idx = CMDQ_SPR_TEMP;
> > > > +
> > > > +	err = cmdq_pkt_assign(pkt, dst_reg_idx, CMDQ_ADDR_HIGH(addr));
> > > > +	if (err < 0)
> > > > +		return err;
> > > > +
> > > > +	if (mask != U32_MAX) {
> > > > +		inst.op = CMDQ_CODE_MASK;
> > > > +		inst.mask = ~mask;
> > > > +		err = cmdq_pkt_append_command(pkt, inst);
> > > > +		if (err < 0)
> > > > +			return err;
> > > > +
> > > > +		inst.op = CMDQ_CODE_WRITE_S_MASK;
> > > > +	} else {
> > > > +		inst.op = CMDQ_CODE_WRITE_S;
> > > > +	}
> > > > +
> > > > +	inst.sop = dst_reg_idx;
> > > > +	inst.offset = CMDQ_ADDR_LOW(addr);
> > > > +	inst.value = value;
> > > > +
> > > > +	return cmdq_pkt_append_command(pkt, inst);
> > > > +}
> > > > +EXPORT_SYMBOL(cmdq_pkt_write_s);
> > > > +
> > > >  int cmdq_pkt_wfe(struct cmdq_pkt *pkt, u16 event)
> > > >  {
> > > >  	struct cmdq_instruction inst = { {0} };
> > > > diff --git a/include/linux/mailbox/mtk-cmdq-mailbox.h b/include/linux/mailbox/mtk-cmdq-mailbox.h
> > > > index 121c3bb..8ef87e1 100644
> > > > --- a/include/linux/mailbox/mtk-cmdq-mailbox.h
> > > > +++ b/include/linux/mailbox/mtk-cmdq-mailbox.h
> > > > @@ -59,6 +59,8 @@ enum cmdq_code {
> > > >  	CMDQ_CODE_JUMP = 0x10,
> > > >  	CMDQ_CODE_WFE = 0x20,
> > > >  	CMDQ_CODE_EOC = 0x40,
> > > > +	CMDQ_CODE_WRITE_S = 0x90,
> > > > +	CMDQ_CODE_WRITE_S_MASK = 0x91,
> > > >  	CMDQ_CODE_LOGIC = 0xa0,
> > > >  };
> > > >  
> > > > diff --git a/include/linux/soc/mediatek/mtk-cmdq.h b/include/linux/soc/mediatek/mtk-cmdq.h
> > > > index 8334021..8dbd046 100644
> > > > --- a/include/linux/soc/mediatek/mtk-cmdq.h
> > > > +++ b/include/linux/soc/mediatek/mtk-cmdq.h
> > > > @@ -12,6 +12,7 @@
> > > >  #include <linux/timer.h>
> > > >  
> > > >  #define CMDQ_NO_TIMEOUT		0xffffffffu
> > > > +#define CMDQ_SPR_TEMP		0
> > > >  
> > > >  struct cmdq_pkt;
> > > >  
> > > > @@ -103,6 +104,18 @@ int cmdq_pkt_write_mask(struct cmdq_pkt *pkt, u8 subsys,
> > > >  			u16 offset, u32 value, u32 mask);
> > > >  
> > > >  /**
> > > > + * cmdq_pkt_write_s() - append write_s command with mask to the CMDQ packet
> > > > + * @pkt:	the CMDQ packet
> > > > + * @addr:	the physical address of register or dma
> > > > + * @value:	the specified target value
> > > > + * @mask:	the specified target mask
> > > > + *
> > > > + * Return: 0 for success; else the error code is returned
> > > > + */
> > > > +int cmdq_pkt_write_s(struct cmdq_pkt *pkt, dma_addr_t addr,
> > > > +		     u32 value, u32 mask);
> > > 
> > > You have an API cmdq_pkt_read_s() which read data into gce internal
> > > register, so I expect that cmdq_pkt_write_s() is an API which write data
> > > from gce internal register, the expected prototype is
> > > 
> > > int cmdq_pkt_write_s(struct cmdq_pkt *pkt, phys_addr_t addr, u16
> > > reg_idx);
> > > 
> > > Your version would confuse the user because you hide the internal
> > > register parameter. If you want to provide this service, I would like
> > > you to change the function name so that user would not be confused and
> > > easily to understand what you want to do in this function.
> > > 
> > > Another choice is: cmdq_pkt_write_s() is implemented in my definition,
> > > and user could call cmdq_pkt_assign() and cmdq_pkt_write_s() to achieve
> > > this function.
> > > 
> > > Regards,
> > > CK
> > > 
> > 
> > Thanks for your comment.
> > 
> > Ok, we have to provide write constant value service to client, so I will
> > change the function name to cmdq_pkt_write_s_value() in this patch.
> > 
> > And since it is better to provide consistent API so I will design
> > another function with interface as your suggestion:
> > int cmdq_pkt_write_s(struct cmdq_pkt *pkt, phys_addr_t addr, u16
> > reg_idx);
> > 
> > In another patch I provide cmdq_pkt_mem_move(). I will move part of
> > implementation to cmdq_pkt_write_s(), so that cmdq_pkt_mem_move() can be
> > combination of cmdq_pkt_read_s() and cmdq_pkt_write_s().
> > 
> > How do you think?
> 
> So cmdq_pkt_read_s()/cmdq_pkt_write_s() are the basic function and
> cmdq_pkt_write_s_value()/cmdq_pkt_mem_move() are combination function. I
> would like to keep the basic function and drop the combination function
> at first. I think what we place in helper is used by two or more
> clients. It's strong believed that basic function could be used by two
> or more client, but it's doubt that combination would be. If only one
> client use this combination, just place the combination in that client.
> If later second client use this combination, we then move the common
> code in helper and both client call the helper function. If you could
> prove that this combination is used by two or more clients now, just
> show me.
> 
> Regards,
> CK
> 

Ok, I'll remove combination function in next version.
Thanks for you comment.


Regards,
Dennis

> > 
> > 
> > Regards,
> > Dennis
> > 
> > > > +
> > > > +/**
> > > >   * cmdq_pkt_wfe() - append wait for event command to the CMDQ packet
> > > >   * @pkt:	the CMDQ packet
> > > >   * @event:	the desired event type to "wait and CLEAR"
> > > 
> > > 
> > 
> > 
> 
>