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

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:

quoted

+#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

quoted

+#define FLD_LS_64(dev, val, field)	\
+	(((u64)(val) << (dev)->hw_shifts[field ## _S]) & (dev)->hw_masks[field ##

_M])

quoted

+#define FLD_RS_64(dev, val, field)	\
+	((u64)((val) & (dev)->hw_masks[field ## _M]) >> (dev)->hw_shifts[field ##

_S])

quoted

+#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/20200602232903.GD65026@mellanox.com/ (local)