From: David Laight <david.laight.linux@gmail.com>

Rather than use a define that should be internal to the implementation
of FIELD_PREP(), pass the shifted 'val' to nfp_eth_set_bit_config()
and change the test for 'value unchanged' to match.

This is a simpler change than the one used to avoid calling both
FIELD_GET() and FIELD_PREP() with non-constant mask values.

Signed-off-by: David Laight <david.laight.linux@gmail.com>
---
 .../ethernet/netronome/nfp/nfpcore/nfp_nsp_eth.c | 16 ++++++----------
 1 file changed, 6 insertions(+), 10 deletions(-)

diff --git a/drivers/net/ethernet/netronome/nfp/nfpcore/nfp_nsp_eth.c b/drivers/net/ethernet/netronome/nfp/nfpcore/nfp_nsp_eth.c
index 5cfddc9a5d87..4a71ff47fbef 100644
--- a/drivers/net/ethernet/netronome/nfp/nfpcore/nfp_nsp_eth.c
+++ b/drivers/net/ethernet/netronome/nfp/nfpcore/nfp_nsp_eth.c
@@ -509,8 +509,7 @@ int nfp_eth_set_configured(struct nfp_cpp *cpp, unsigned int idx, bool configed)
 
 static int
 nfp_eth_set_bit_config(struct nfp_nsp *nsp, unsigned int raw_idx,
-		       const u64 mask, const unsigned int shift,
-		       u64 val, const u64 ctrl_bit)
+		       const u64 mask, u64 shifted_val, const u64 ctrl_bit)
 {
 	union eth_table_entry *entries = nfp_nsp_config_entries(nsp);
 	unsigned int idx = nfp_nsp_config_idx(nsp);
@@ -527,11 +526,11 @@ nfp_eth_set_bit_config(struct nfp_nsp *nsp, unsigned int raw_idx,
 
 	/* Check if we are already in requested state */
 	reg = le64_to_cpu(entries[idx].raw[raw_idx]);
-	if (val == (reg & mask) >> shift)
+	if (shifted_val == (reg & mask))
 		return 0;
 
 	reg &= ~mask;
-	reg |= (val << shift) & mask;
+	reg |= shifted_val;
 	entries[idx].raw[raw_idx] = cpu_to_le64(reg);
 
 	entries[idx].control |= cpu_to_le64(ctrl_bit);
@@ -571,12 +570,9 @@ int nfp_eth_set_idmode(struct nfp_cpp *cpp, unsigned int idx, bool state)
 	return nfp_eth_config_commit_end(nsp);
 }
 
-#define NFP_ETH_SET_BIT_CONFIG(nsp, raw_idx, mask, val, ctrl_bit)	\
-	({								\
-		__BF_FIELD_CHECK(mask, 0ULL, val, "NFP_ETH_SET_BIT_CONFIG: "); \
-		nfp_eth_set_bit_config(nsp, raw_idx, mask, __bf_shf(mask), \
-				       val, ctrl_bit);			\
-	})
+#define NFP_ETH_SET_BIT_CONFIG(nsp, raw_idx, mask, val, ctrl_bit)	  \
+	nfp_eth_set_bit_config(nsp, raw_idx, mask, FIELD_PREP(mask, val), \
+			       ctrl_bit)
 
 /**
  * __nfp_eth_set_aneg() - set PHY autonegotiation control bit
-- 
2.39.5

On Tue,  9 Dec 2025 10:03:05 +0000 david.laight.linux@gmail.com wrote:
> Rather than use a define that should be internal to the implementation
> of FIELD_PREP(), pass the shifted 'val' to nfp_eth_set_bit_config()
> and change the test for 'value unchanged' to match.
> 
> This is a simpler change than the one used to avoid calling both
> FIELD_GET() and FIELD_PREP() with non-constant mask values.

I'd like this code to be left out of the subjective churn please.
I like it the way I wrote it. I also liked the bitfield.h the way
I wrote it but I guess that part "belongs" to the community at large.

FWIW - thumbs up for patch 8, no opinion on the rest.

On Wed, 10 Dec 2025 18:29:47 +0900
Jakub Kicinski <kuba@kernel.org> wrote:

> On Tue,  9 Dec 2025 10:03:05 +0000 david.laight.linux@gmail.com wrote:
> > Rather than use a define that should be internal to the implementation
> > of FIELD_PREP(), pass the shifted 'val' to nfp_eth_set_bit_config()
> > and change the test for 'value unchanged' to match.
> > 
> > This is a simpler change than the one used to avoid calling both
> > FIELD_GET() and FIELD_PREP() with non-constant mask values.  
> 
> I'd like this code to be left out of the subjective churn please.
> I like it the way I wrote it.

The 'problem' is that I want to remove __BF_FIELD_CHECK().
It has already been split into two (for 6.19) but it makes sense
to split into three (to avoid code-bloat in the cpp output).

IMHO Using a define that is part of the implementation of FIELD_xxxx()
is wrong anyway.

> I also liked the bitfield.h the way
> I wrote it but I guess that part "belongs" to the community at large.

There are already significant changes there for 6.19-rc1

	David

> 
> FWIW - thumbs up for patch 8, no opinion on the rest.