Subject: RE: [PATCH 09/22] RDMA/irdma: Implement HW Admin Queue OPs

From: "Saleem, Shiraz" <[email-masked]>
Date: Wed, 27 Jan 2021 00:41:59 +0000

> Subject: Re: [PATCH 09/22] RDMA/irdma: Implement HW Admin Queue OPs
> 
> On Fri, Jan 22, 2021 at 05:48:14PM -0600, Shiraz Saleem wrote:
> > +#define LS_64_1(val, bits)	((u64)(uintptr_t)(val) << (bits))
> > +#define RS_64_1(val, bits)	((u64)(uintptr_t)(val) >> (bits))
> > +#define LS_32_1(val, bits)	((u32)((val) << (bits)))
> > +#define RS_32_1(val, bits)	((u32)((val) >> (bits)))
> > +#define LS_64(val, field)	(((u64)(val) << field ## _S) & (field ## _M))
> > +#define RS_64(val, field)	((u64)((val) & field ## _M) >> field ## _S)
> > +#define LS_32(val, field)	(((val) << field ## _S) & (field ## _M))
> > +#define RS_32(val, field)	(((val) & field ## _M) >> field ## _S)
> 
> Yikes, why can't this use the normal GENMASK/FIELD_PREP infrastructure like the
> other new drivers are now doing?
> 
> EFA is not a perfect example, but EFA_GET/EFA_SET are the macros I would
> expect to see, just without the _MASK thing.
> 
> IBA_GET/SET shows how to do that pattern
> 
> > +#define FLD_LS_64(dev, val, field)	\
> > +	(((u64)(val) << (dev)->hw_shifts[field ## _S]) & (dev)->hw_masks[field ##
> _M])
> > +#define FLD_RS_64(dev, val, field)	\
> > +	((u64)((val) & (dev)->hw_masks[field ## _M]) >> (dev)->hw_shifts[field ##
> _S])
> > +#define FLD_LS_32(dev, val, field)	\
> > +	(((val) << (dev)->hw_shifts[field ## _S]) & (dev)->hw_masks[field ## _M])
> > +#define FLD_RS_32(dev, val, field)	\
> > +	((u64)((val) & (dev)->hw_masks[field ## _M]) >>
> > +(dev)->hw_shifts[field ## _S])
> 
> Is it because the register access is programmable? That shouldn't be a significant
> problem.
> 

Yes. How do we solve that?

https://lore.kernel.org/linux-rdma/[email-masked]/