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[PATCH net-next 6/6] net: macb: Add MACB_CAPS_QBV capability flag for IEEE 802.1Qbv support

Vineeth Karumanchi posted 6 patches 2 months, 2 weeks ago
There is a newer version of this series
[PATCH net-next 6/6] net: macb: Add MACB_CAPS_QBV capability flag for IEEE 802.1Qbv support
Posted by Vineeth Karumanchi 2 months, 2 weeks ago 
The "exclude_qbv" bit in designcfg_debug1 register varies between MACB/GEM
IP revisions, making direct register probing unreliable for
feature detection. A capability-based approach provides consistent
QBV support identification across the IP family

Platform support:
- Enable MACB_CAPS_QBV for Xilinx Versal platform configuration
- Foundation for QBV feature detection in TAPRIO implementation

Signed-off-by: Vineeth Karumanchi <vineeth.karumanchi@amd.com>
---
 drivers/net/ethernet/cadence/macb.h      | 1 +
 drivers/net/ethernet/cadence/macb_main.c | 6 +++++-
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/cadence/macb.h b/drivers/net/ethernet/cadence/macb.h
index ef3995564c5c..4e8d5dcc814e 100644
--- a/drivers/net/ethernet/cadence/macb.h
+++ b/drivers/net/ethernet/cadence/macb.h
@@ -782,6 +782,7 @@
 #define MACB_CAPS_MIIONRGMII			0x00000200
 #define MACB_CAPS_NEED_TSUCLK			0x00000400
 #define MACB_CAPS_QUEUE_DISABLE			0x00000800
+#define MACB_CAPS_QBV				0x00001000
 #define MACB_CAPS_PCS				0x01000000
 #define MACB_CAPS_HIGH_SPEED			0x02000000
 #define MACB_CAPS_CLK_HW_CHG			0x04000000
diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c
index cc33491930e3..98e56697661c 100644
--- a/drivers/net/ethernet/cadence/macb_main.c
+++ b/drivers/net/ethernet/cadence/macb_main.c
@@ -4601,6 +4601,10 @@ static int macb_init(struct platform_device *pdev)
 		dev->hw_features |= NETIF_F_HW_CSUM | NETIF_F_RXCSUM;
 	if (bp->caps & MACB_CAPS_SG_DISABLED)
 		dev->hw_features &= ~NETIF_F_SG;
+	/* Enable HW_TC if hardware supports QBV */
+	if (bp->caps & MACB_CAPS_QBV)
+		dev->hw_features |= NETIF_F_HW_TC;
+
 	dev->features = dev->hw_features;
 
 	/* Check RX Flow Filters support.
@@ -5345,7 +5349,7 @@ static const struct macb_config sama7g5_emac_config = {
 static const struct macb_config versal_config = {
 	.caps = MACB_CAPS_GIGABIT_MODE_AVAILABLE | MACB_CAPS_JUMBO |
 		MACB_CAPS_GEM_HAS_PTP | MACB_CAPS_BD_RD_PREFETCH | MACB_CAPS_NEED_TSUCLK |
-		MACB_CAPS_QUEUE_DISABLE,
+		MACB_CAPS_QUEUE_DISABLE, MACB_CAPS_QBV,
 	.dma_burst_length = 16,
 	.clk_init = macb_clk_init,
 	.init = init_reset_optional,
-- 
2.34.1
Re: [PATCH net-next 6/6] net: macb: Add MACB_CAPS_QBV capability flag for IEEE 802.1Qbv support
Posted by kernel test robot 2 months, 2 weeks ago 
Hi Vineeth,

kernel test robot noticed the following build warnings:

[auto build test WARNING on net-next/main]

url:    https://github.com/intel-lab-lkp/linux/commits/Vineeth-Karumanchi/net-macb-Define-ENST-hardware-registers-for-time-aware-scheduling/20250722-234618
base:   net-next/main
patch link:    https://lore.kernel.org/r/20250722154111.1871292-7-vineeth.karumanchi%40amd.com
patch subject: [PATCH net-next 6/6] net: macb: Add MACB_CAPS_QBV capability flag for IEEE 802.1Qbv support
config: parisc-randconfig-r131-20250724 (https://download.01.org/0day-ci/archive/20250724/202507240825.lVN6sSiB-lkp@intel.com/config)
compiler: hppa-linux-gcc (GCC) 14.3.0
reproduce: (https://download.01.org/0day-ci/archive/20250724/202507240825.lVN6sSiB-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202507240825.lVN6sSiB-lkp@intel.com/

sparse warnings: (new ones prefixed by >>)
   drivers/net/ethernet/cadence/macb_main.c:282:16: sparse: sparse: incorrect type in assignment (different base types) @@     expected unsigned int [usertype] bottom @@     got restricted __le32 [usertype] @@
   drivers/net/ethernet/cadence/macb_main.c:282:16: sparse:     expected unsigned int [usertype] bottom
   drivers/net/ethernet/cadence/macb_main.c:282:16: sparse:     got restricted __le32 [usertype]
   drivers/net/ethernet/cadence/macb_main.c:284:13: sparse: sparse: incorrect type in assignment (different base types) @@     expected unsigned short [usertype] top @@     got restricted __le16 [usertype] @@
   drivers/net/ethernet/cadence/macb_main.c:284:13: sparse:     expected unsigned short [usertype] top
   drivers/net/ethernet/cadence/macb_main.c:284:13: sparse:     got restricted __le16 [usertype]
   drivers/net/ethernet/cadence/macb_main.c:3645:39: sparse: sparse: restricted __be32 degrades to integer
   drivers/net/ethernet/cadence/macb_main.c:3650:39: sparse: sparse: restricted __be32 degrades to integer
   drivers/net/ethernet/cadence/macb_main.c:3655:40: sparse: sparse: restricted __be16 degrades to integer
   drivers/net/ethernet/cadence/macb_main.c:3655:69: sparse: sparse: restricted __be16 degrades to integer
   drivers/net/ethernet/cadence/macb_main.c:3680:20: sparse: sparse: restricted __be32 degrades to integer
   drivers/net/ethernet/cadence/macb_main.c:3684:20: sparse: sparse: incorrect type in assignment (different base types) @@     expected unsigned int [assigned] [usertype] w0 @@     got restricted __be32 [usertype] ip4src @@
   drivers/net/ethernet/cadence/macb_main.c:3684:20: sparse:     expected unsigned int [assigned] [usertype] w0
   drivers/net/ethernet/cadence/macb_main.c:3684:20: sparse:     got restricted __be32 [usertype] ip4src
   drivers/net/ethernet/cadence/macb_main.c:3694:20: sparse: sparse: restricted __be32 degrades to integer
   drivers/net/ethernet/cadence/macb_main.c:3698:20: sparse: sparse: incorrect type in assignment (different base types) @@     expected unsigned int [assigned] [usertype] w0 @@     got restricted __be32 [usertype] ip4dst @@
   drivers/net/ethernet/cadence/macb_main.c:3698:20: sparse:     expected unsigned int [assigned] [usertype] w0
   drivers/net/ethernet/cadence/macb_main.c:3698:20: sparse:     got restricted __be32 [usertype] ip4dst
   drivers/net/ethernet/cadence/macb_main.c:3708:21: sparse: sparse: restricted __be16 degrades to integer
   drivers/net/ethernet/cadence/macb_main.c:3708:50: sparse: sparse: restricted __be16 degrades to integer
   drivers/net/ethernet/cadence/macb_main.c:3714:30: sparse: sparse: restricted __be16 degrades to integer
   drivers/net/ethernet/cadence/macb_main.c:3715:30: sparse: sparse: restricted __be16 degrades to integer
   drivers/net/ethernet/cadence/macb_main.c:3722:36: sparse: sparse: restricted __be16 degrades to integer
   drivers/net/ethernet/cadence/macb_main.c:3723:38: sparse: sparse: restricted __be16 degrades to integer
   drivers/net/ethernet/cadence/macb_main.c:3726:38: sparse: sparse: restricted __be16 degrades to integer
   drivers/net/ethernet/cadence/macb_main.c:3762:9: sparse: sparse: cast from restricted __be32
   drivers/net/ethernet/cadence/macb_main.c:3762:9: sparse: sparse: cast from restricted __be32
   drivers/net/ethernet/cadence/macb_main.c:3816:25: sparse: sparse: cast from restricted __be32
   drivers/net/ethernet/cadence/macb_main.c:3816:25: sparse: sparse: cast from restricted __be32
>> drivers/net/ethernet/cadence/macb_main.c:5352:42: sparse: sparse: Initializer entry defined twice
   drivers/net/ethernet/cadence/macb_main.c:5353:10: sparse:   also defined here

vim +5352 drivers/net/ethernet/cadence/macb_main.c

  5348	
  5349	static const struct macb_config versal_config = {
  5350		.caps = MACB_CAPS_GIGABIT_MODE_AVAILABLE | MACB_CAPS_JUMBO |
  5351			MACB_CAPS_GEM_HAS_PTP | MACB_CAPS_BD_RD_PREFETCH | MACB_CAPS_NEED_TSUCLK |
> 5352			MACB_CAPS_QUEUE_DISABLE, MACB_CAPS_QBV,
  5353		.dma_burst_length = 16,
  5354		.clk_init = macb_clk_init,
  5355		.init = init_reset_optional,
  5356		.jumbo_max_len = 10240,
  5357		.usrio = &macb_default_usrio,
  5358	};
  5359	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
Re: [PATCH net-next 6/6] net: macb: Add MACB_CAPS_QBV capability flag for IEEE 802.1Qbv support
Posted by Simon Horman 2 months, 2 weeks ago 
On Tue, Jul 22, 2025 at 09:11:11PM +0530, Vineeth Karumanchi wrote:
> The "exclude_qbv" bit in designcfg_debug1 register varies between MACB/GEM
> IP revisions, making direct register probing unreliable for
> feature detection. A capability-based approach provides consistent
> QBV support identification across the IP family
> 
> Platform support:
> - Enable MACB_CAPS_QBV for Xilinx Versal platform configuration
> - Foundation for QBV feature detection in TAPRIO implementation
> 
> Signed-off-by: Vineeth Karumanchi <vineeth.karumanchi@amd.com>

...

> diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c
> index cc33491930e3..98e56697661c 100644
> --- a/drivers/net/ethernet/cadence/macb_main.c
> +++ b/drivers/net/ethernet/cadence/macb_main.c
> @@ -4601,6 +4601,10 @@ static int macb_init(struct platform_device *pdev)
>  		dev->hw_features |= NETIF_F_HW_CSUM | NETIF_F_RXCSUM;
>  	if (bp->caps & MACB_CAPS_SG_DISABLED)
>  		dev->hw_features &= ~NETIF_F_SG;
> +	/* Enable HW_TC if hardware supports QBV */
> +	if (bp->caps & MACB_CAPS_QBV)
> +		dev->hw_features |= NETIF_F_HW_TC;
> +
>  	dev->features = dev->hw_features;
>  
>  	/* Check RX Flow Filters support.
> @@ -5345,7 +5349,7 @@ static const struct macb_config sama7g5_emac_config = {
>  static const struct macb_config versal_config = {
>  	.caps = MACB_CAPS_GIGABIT_MODE_AVAILABLE | MACB_CAPS_JUMBO |
>  		MACB_CAPS_GEM_HAS_PTP | MACB_CAPS_BD_RD_PREFETCH | MACB_CAPS_NEED_TSUCLK |
> -		MACB_CAPS_QUEUE_DISABLE,
> +		MACB_CAPS_QUEUE_DISABLE, MACB_CAPS_QBV,

Hi Vineeth,

TL;DR: I think you mean

		MACB_CAPS_QUEUE_DISABLE | MACB_CAPS_QBV,
		                       ^^^

I assume that the intention here is to set the MACB_CAPS_QBV bit of .caps.
However, because there is a comma rather than a pipe between
it and MACB_CAPS_QUEUE_DISABLE the effect is to leave .caps as
it was before, and set .dma_burst_length to MACB_CAPS_QBV.
.dma_burst_length is then overwritten on the following line.

Flagged by W=1 builds with Clang 20.1.8 and 15.1.0.

Please build your patches with W=1 and try to avoid adding warnings
it flags.

Also, while we are here, it would be nice to fix up the line wrapping so
the adjacent code is 80 columns wide or less, as is still preferred in
Networking code.

	.caps = MACB_CAPS_GIGABIT_MODE_AVAILABLE | MACB_CAPS_JUMBO |
		MACB_CAPS_GEM_HAS_PTP | MACB_CAPS_BD_RD_PREFETCH |
		MACB_CAPS_NEED_TSUCLK | MACB_CAPS_QUEUE_DISABLE |
		MACB_CAPS_QBV,

>  	.dma_burst_length = 16,
>  	.clk_init = macb_clk_init,
>  	.init = init_reset_optional,
> -- 
> 2.34.1
> 
>
Re: [PATCH net-next 6/6] net: macb: Add MACB_CAPS_QBV capability flag for IEEE 802.1Qbv support
Posted by Karumanchi, Vineeth 2 months, 1 week ago 
Hi Simon,

On 7/24/2025 12:35 AM, Simon Horman wrote:

<...>

>> @@ -5345,7 +5349,7 @@ static const struct macb_config sama7g5_emac_config = {
>>   static const struct macb_config versal_config = {
>>   	.caps = MACB_CAPS_GIGABIT_MODE_AVAILABLE | MACB_CAPS_JUMBO |
>>   		MACB_CAPS_GEM_HAS_PTP | MACB_CAPS_BD_RD_PREFETCH | MACB_CAPS_NEED_TSUCLK |
>> -		MACB_CAPS_QUEUE_DISABLE,
>> +		MACB_CAPS_QUEUE_DISABLE, MACB_CAPS_QBV,
> Hi Vineeth,
> 
> TL;DR: I think you mean
> 
> 		MACB_CAPS_QUEUE_DISABLE | MACB_CAPS_QBV,
> 		                       ^^^
> 

Yes, since there's no strict validation for the presence of 
NETIF_F_HW_TC, the tc add/replace command succeeded. I've submitted an 
RFC patch to enforce stricter checks for NETIF_F_HW_TC within 
dev->hw_features

> I assume that the intention here is to set the MACB_CAPS_QBV bit of .caps.
> However, because there is a comma rather than a pipe between
> it and MACB_CAPS_QUEUE_DISABLE the effect is to leave .caps as
> it was before, and set .dma_burst_length to MACB_CAPS_QBV.
> .dma_burst_length is then overwritten on the following line.
> 
> Flagged by W=1 builds with Clang 20.1.8 and 15.1.0.
> 
> Please build your patches with W=1 and try to avoid adding warnings
> it flags.
> 
> Also, while we are here, it would be nice to fix up the line wrapping so
> the adjacent code is 80 columns wide or less, as is still preferred in
> Networking code.
> 
> 	.caps = MACB_CAPS_GIGABIT_MODE_AVAILABLE | MACB_CAPS_JUMBO |
> 		MACB_CAPS_GEM_HAS_PTP | MACB_CAPS_BD_RD_PREFETCH |
> 		MACB_CAPS_NEED_TSUCLK | MACB_CAPS_QUEUE_DISABLE |
> 		MACB_CAPS_QBV,
> 

OK.

Thanks,
-- 
🙏 vineeth

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