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[PATCH net-next 12/13] net: dsa: lantiq_gswip: Add and use a GSWIP_TABLE_MAC_BRIDGE_FID macro

Martin Schiller posted 13 patches 1 year, 8 months ago
There is a newer version of this series
[PATCH net-next 12/13] net: dsa: lantiq_gswip: Add and use a GSWIP_TABLE_MAC_BRIDGE_FID macro
Posted by Martin Schiller 1 year, 8 months ago 
From: Martin Blumenstingl <martin.blumenstingl@googlemail.com>

Only bits [5:0] in mac_bridge.key[3] are reserved for the FID. Add a
macro so this becomes obvious when reading the driver code.

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
---
 drivers/net/dsa/lantiq_gswip.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/net/dsa/lantiq_gswip.c b/drivers/net/dsa/lantiq_gswip.c
index f2faee112e33..4bb894e75b81 100644
--- a/drivers/net/dsa/lantiq_gswip.c
+++ b/drivers/net/dsa/lantiq_gswip.c
@@ -238,6 +238,7 @@
 #define GSWIP_TABLE_MAC_BRIDGE		0x0b
 #define  GSWIP_TABLE_MAC_BRIDGE_STATIC	BIT(0)		/* Static not, aging entry */
 #define  GSWIP_TABLE_MAC_BRIDGE_PORT	GENMASK(7, 4)	/* Port on learned entries */
+#define  GSWIP_TABLE_MAC_BRIDGE_FID	GENMASK(5, 0)	/* Filtering identifier */
 
 #define XRX200_GPHY_FW_ALIGN	(16 * 1024)
 
@@ -1385,7 +1386,7 @@ static int gswip_port_fdb(struct dsa_switch *ds, int port,
 	mac_bridge.key[0] = addr[5] | (addr[4] << 8);
 	mac_bridge.key[1] = addr[3] | (addr[2] << 8);
 	mac_bridge.key[2] = addr[1] | (addr[0] << 8);
-	mac_bridge.key[3] = fid;
+	mac_bridge.key[3] = FIELD_PREP(GSWIP_TABLE_MAC_BRIDGE_FID, fid);
 	mac_bridge.val[0] = add ? BIT(port) : 0; /* port map */
 	mac_bridge.val[1] = GSWIP_TABLE_MAC_BRIDGE_STATIC;
 	mac_bridge.valid = add;
-- 
2.39.2
Re: [PATCH net-next 12/13] net: dsa: lantiq_gswip: Add and use a GSWIP_TABLE_MAC_BRIDGE_FID macro
Posted by Vladimir Oltean 1 year, 8 months ago 
On Thu, Jun 06, 2024 at 10:52:33AM +0200, Martin Schiller wrote:
> From: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
> 
> Only bits [5:0] in mac_bridge.key[3] are reserved for the FID. Add a
> macro so this becomes obvious when reading the driver code.
> 
> Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
> ---
>  drivers/net/dsa/lantiq_gswip.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/dsa/lantiq_gswip.c b/drivers/net/dsa/lantiq_gswip.c
> index f2faee112e33..4bb894e75b81 100644
> --- a/drivers/net/dsa/lantiq_gswip.c
> +++ b/drivers/net/dsa/lantiq_gswip.c
> @@ -238,6 +238,7 @@
>  #define GSWIP_TABLE_MAC_BRIDGE		0x0b
>  #define  GSWIP_TABLE_MAC_BRIDGE_STATIC	BIT(0)		/* Static not, aging entry */
>  #define  GSWIP_TABLE_MAC_BRIDGE_PORT	GENMASK(7, 4)	/* Port on learned entries */
> +#define  GSWIP_TABLE_MAC_BRIDGE_FID	GENMASK(5, 0)	/* Filtering identifier */
>  
>  #define XRX200_GPHY_FW_ALIGN	(16 * 1024)
>  
> @@ -1385,7 +1386,7 @@ static int gswip_port_fdb(struct dsa_switch *ds, int port,
>  	mac_bridge.key[0] = addr[5] | (addr[4] << 8);
>  	mac_bridge.key[1] = addr[3] | (addr[2] << 8);
>  	mac_bridge.key[2] = addr[1] | (addr[0] << 8);
> -	mac_bridge.key[3] = fid;
> +	mac_bridge.key[3] = FIELD_PREP(GSWIP_TABLE_MAC_BRIDGE_FID, fid);
>  	mac_bridge.val[0] = add ? BIT(port) : 0; /* port map */
>  	mac_bridge.val[1] = GSWIP_TABLE_MAC_BRIDGE_STATIC;
>  	mac_bridge.valid = add;
> -- 
> 2.39.2

On second thought, I disagree with the naming scheme of the
GSWIP_TABLE_MAC_BRIDGE_* macros. It is completely non obvious that they
are non-overlapping, because they have the same name prefix, but:
_STATIC applies to gswip_pce_table_entry :: val[1]
_PORT applies to gswip_pce_table_entry :: val[0]
_FID applies to gswip_pce_table_entry :: key[3]

I think it's all too easy to use the wrong macro on the wrong register field.
If the macros incorporated names like VAL1, KEY3 etc, it would be much
more obvious. Could you please do that?
Re: [PATCH net-next 12/13] net: dsa: lantiq_gswip: Add and use a GSWIP_TABLE_MAC_BRIDGE_FID macro
Posted by Martin Schiller 1 year, 8 months ago 
On 2024-06-07 13:36, Vladimir Oltean wrote:
> On Thu, Jun 06, 2024 at 10:52:33AM +0200, Martin Schiller wrote:
>> From: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
>> 
>> Only bits [5:0] in mac_bridge.key[3] are reserved for the FID. Add a
>> macro so this becomes obvious when reading the driver code.
>> 
>> Signed-off-by: Martin Blumenstingl 
>> <martin.blumenstingl@googlemail.com>
>> ---
>>  drivers/net/dsa/lantiq_gswip.c | 3 ++-
>>  1 file changed, 2 insertions(+), 1 deletion(-)
>> 
>> diff --git a/drivers/net/dsa/lantiq_gswip.c 
>> b/drivers/net/dsa/lantiq_gswip.c
>> index f2faee112e33..4bb894e75b81 100644
>> --- a/drivers/net/dsa/lantiq_gswip.c
>> +++ b/drivers/net/dsa/lantiq_gswip.c
>> @@ -238,6 +238,7 @@
>>  #define GSWIP_TABLE_MAC_BRIDGE		0x0b
>>  #define  GSWIP_TABLE_MAC_BRIDGE_STATIC	BIT(0)		/* Static not, aging 
>> entry */
>>  #define  GSWIP_TABLE_MAC_BRIDGE_PORT	GENMASK(7, 4)	/* Port on learned 
>> entries */
>> +#define  GSWIP_TABLE_MAC_BRIDGE_FID	GENMASK(5, 0)	/* Filtering 
>> identifier */
>> 
>>  #define XRX200_GPHY_FW_ALIGN	(16 * 1024)
>> 
>> @@ -1385,7 +1386,7 @@ static int gswip_port_fdb(struct dsa_switch *ds, 
>> int port,
>>  	mac_bridge.key[0] = addr[5] | (addr[4] << 8);
>>  	mac_bridge.key[1] = addr[3] | (addr[2] << 8);
>>  	mac_bridge.key[2] = addr[1] | (addr[0] << 8);
>> -	mac_bridge.key[3] = fid;
>> +	mac_bridge.key[3] = FIELD_PREP(GSWIP_TABLE_MAC_BRIDGE_FID, fid);
>>  	mac_bridge.val[0] = add ? BIT(port) : 0; /* port map */
>>  	mac_bridge.val[1] = GSWIP_TABLE_MAC_BRIDGE_STATIC;
>>  	mac_bridge.valid = add;
>> --
>> 2.39.2
> 
> On second thought, I disagree with the naming scheme of the
> GSWIP_TABLE_MAC_BRIDGE_* macros. It is completely non obvious that they
> are non-overlapping, because they have the same name prefix, but:
> _STATIC applies to gswip_pce_table_entry :: val[1]
> _PORT applies to gswip_pce_table_entry :: val[0]
> _FID applies to gswip_pce_table_entry :: key[3]
> 
> I think it's all too easy to use the wrong macro on the wrong register 
> field.
> If the macros incorporated names like VAL1, KEY3 etc, it would be much
> more obvious. Could you please do that?

OK, so I'll change the macro names to

GSWIP_TABLE_MAC_BRIDGE_KEY3_FID
GSWIP_TABLE_MAC_BRIDGE_VAL0_PORT
GSWIP_TABLE_MAC_BRIDGE_VAL1_STATIC

Also the comment of GSWIP_TABLE_MAC_BRIDGE_VAL1_STATIC should be changed 
to
/* Static, not aging entry */

While looking again at this diff above, I noticed that val[0] is set
incorrectly. Shouldn't it be either "port << 4" or (after the previous 
patch)
"FIELD_PREP(GSWIP_TABLE_MAC_BRIDGE_PORT, port);" instead of "BIT(port)"?
Re: [PATCH net-next 12/13] net: dsa: lantiq_gswip: Add and use a GSWIP_TABLE_MAC_BRIDGE_FID macro
Posted by Martin Schiller 1 year, 8 months ago 
On 2024-06-07 16:27, Martin Schiller wrote:
> While looking again at this diff above, I noticed that val[0] is set
> incorrectly. Shouldn't it be either "port << 4" or (after the previous 
> patch)
> "FIELD_PREP(GSWIP_TABLE_MAC_BRIDGE_PORT, port);" instead of 
> "BIT(port)"?

Please ignore this comment. The format of the port specification differs
for static and dynamic (learned) entries.

Patchew 2.1-devel-b67e4c2

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