[PATCH iwl-net] i40e: Fix wrong mask used during DCB config

[PATCH iwl-net] i40e: Fix wrong mask used during DCB config

[Ivan Vecera]

Mask used for clearing PRTDCB_RETSTCC register in function
i40e_dcb_hw_rx_ets_bw_config() is incorrect as there is used
define I40E_PRTDCB_RETSTCC_ETSTC_SHIFT instead of define
I40E_PRTDCB_RETSTCC_ETSTC_MASK.

The PRTDCB_RETSTCC register is used to configure whether ETS
or strict priority is used as TSA in Rx for particular TC.

In practice it means that once the register is set to use ETS
as TSA then it is not possible to switch back to strict priority
without CoreR reset.

Fix the value in the clearing mask.

Fixes: 90bc8e003be2 ("i40e: Add hardware configuration for software based DCB")
Signed-off-by: Ivan Vecera <ivecera@redhat.com>
---
 drivers/net/ethernet/intel/i40e/i40e_dcb.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/intel/i40e/i40e_dcb.c b/drivers/net/ethernet/intel/i40e/i40e_dcb.c
index 68602fc375f6..073ffbfcbe8d 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_dcb.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_dcb.c
@@ -1576,7 +1576,7 @@ void i40e_dcb_hw_rx_ets_bw_config(struct i40e_hw *hw, u8 *bw_share,
 		reg = rd32(hw, I40E_PRTDCB_RETSTCC(i));
 		reg &= ~(I40E_PRTDCB_RETSTCC_BWSHARE_MASK     |
 			 I40E_PRTDCB_RETSTCC_UPINTC_MODE_MASK |
-			 I40E_PRTDCB_RETSTCC_ETSTC_SHIFT);
+			 I40E_PRTDCB_RETSTCC_ETSTC_MASK);
 		reg |= ((u32)bw_share[i] << I40E_PRTDCB_RETSTCC_BWSHARE_SHIFT) &
 			 I40E_PRTDCB_RETSTCC_BWSHARE_MASK;
 		reg |= ((u32)mode[i] << I40E_PRTDCB_RETSTCC_UPINTC_MODE_SHIFT) &
-- 
2.41.0

Re: [Intel-wired-lan] [PATCH iwl-net] i40e: Fix wrong mask used during DCB config

[Przemek Kitszel]

On 11/30/23 20:31, Ivan Vecera wrote:
> Mask used for clearing PRTDCB_RETSTCC register in function
> i40e_dcb_hw_rx_ets_bw_config() is incorrect as there is used
> define I40E_PRTDCB_RETSTCC_ETSTC_SHIFT instead of define
> I40E_PRTDCB_RETSTCC_ETSTC_MASK.
> 
> The PRTDCB_RETSTCC register is used to configure whether ETS
> or strict priority is used as TSA in Rx for particular TC.
> 
> In practice it means that once the register is set to use ETS
> as TSA then it is not possible to switch back to strict priority
> without CoreR reset.
> 
> Fix the value in the clearing mask.
> 
> Fixes: 90bc8e003be2 ("i40e: Add hardware configuration for software based DCB")
> Signed-off-by: Ivan Vecera <ivecera@redhat.com>
> ---
>   drivers/net/ethernet/intel/i40e/i40e_dcb.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/net/ethernet/intel/i40e/i40e_dcb.c b/drivers/net/ethernet/intel/i40e/i40e_dcb.c
> index 68602fc375f6..073ffbfcbe8d 100644
> --- a/drivers/net/ethernet/intel/i40e/i40e_dcb.c
> +++ b/drivers/net/ethernet/intel/i40e/i40e_dcb.c
> @@ -1576,7 +1576,7 @@ void i40e_dcb_hw_rx_ets_bw_config(struct i40e_hw *hw, u8 *bw_share,
>   		reg = rd32(hw, I40E_PRTDCB_RETSTCC(i));
>   		reg &= ~(I40E_PRTDCB_RETSTCC_BWSHARE_MASK     |
>   			 I40E_PRTDCB_RETSTCC_UPINTC_MODE_MASK |
> -			 I40E_PRTDCB_RETSTCC_ETSTC_SHIFT);
> +			 I40E_PRTDCB_RETSTCC_ETSTC_MASK);
>   		reg |= ((u32)bw_share[i] << I40E_PRTDCB_RETSTCC_BWSHARE_SHIFT) &
>   			 I40E_PRTDCB_RETSTCC_BWSHARE_MASK;
>   		reg |= ((u32)mode[i] << I40E_PRTDCB_RETSTCC_UPINTC_MODE_SHIFT) &

Thank you!

Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>

Re: [PATCH iwl-net] i40e: Fix wrong mask used during DCB config

[Simon Horman]

On Thu, Nov 30, 2023 at 08:31:34PM +0100, Ivan Vecera wrote:
> Mask used for clearing PRTDCB_RETSTCC register in function
> i40e_dcb_hw_rx_ets_bw_config() is incorrect as there is used
> define I40E_PRTDCB_RETSTCC_ETSTC_SHIFT instead of define
> I40E_PRTDCB_RETSTCC_ETSTC_MASK.
> 
> The PRTDCB_RETSTCC register is used to configure whether ETS
> or strict priority is used as TSA in Rx for particular TC.
> 
> In practice it means that once the register is set to use ETS
> as TSA then it is not possible to switch back to strict priority
> without CoreR reset.
> 
> Fix the value in the clearing mask.
> 
> Fixes: 90bc8e003be2 ("i40e: Add hardware configuration for software based DCB")
> Signed-off-by: Ivan Vecera <ivecera@redhat.com>

Reviewed-by: Simon Horman <horms@kernel.org>

RE: [Intel-wired-lan] [PATCH iwl-net] i40e: Fix wrong mask used during DCB config

[Pucha, HimasekharX Reddy]

> -----Original Message-----
> From: Intel-wired-lan <intel-wired-lan-bounces@osuosl.org> On Behalf Of Ivan Vecera
> Sent: Friday, December 1, 2023 1:02 AM
> To: netdev@vger.kernel.org
> Cc: moderated list:INTEL ETHERNET DRIVERS <intel-wired-lan@lists.osuosl.org>; Brandeburg, Jesse <jesse.brandeburg@intel.com>; Kubalewski, Arkadiusz <arkadiusz.kubalewski@intel.com>; Loktionov, Aleksandr <aleksandr.loktionov@intel.com>; Eric Dumazet <edumazet@google.com>; Nguyen, Anthony L <anthony.l.nguyen@intel.com>; Jakub Kicinski <kuba@kernel.org>; Paolo Abeni <pabeni@redhat.com>; David S. Miller <davem@davemloft.net>; open list <linux-kernel@vger.kernel.org>
> Subject: [Intel-wired-lan] [PATCH iwl-net] i40e: Fix wrong mask used during DCB config
>
> Mask used for clearing PRTDCB_RETSTCC register in function
> i40e_dcb_hw_rx_ets_bw_config() is incorrect as there is used
> define I40E_PRTDCB_RETSTCC_ETSTC_SHIFT instead of define
> I40E_PRTDCB_RETSTCC_ETSTC_MASK.
>
> The PRTDCB_RETSTCC register is used to configure whether ETS
> or strict priority is used as TSA in Rx for particular TC.
>
> In practice it means that once the register is set to use ETS
> as TSA then it is not possible to switch back to strict priority
> without CoreR reset.
>
> Fix the value in the clearing mask.
>
> Fixes: 90bc8e003be2 ("i40e: Add hardware configuration for software based DCB")
> Signed-off-by: Ivan Vecera <ivecera@redhat.com>
> ---
>  drivers/net/ethernet/intel/i40e/i40e_dcb.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>

Tested-by: Pucha Himasekhar Reddy <himasekharx.reddy.pucha@intel.com> (A Contingent worker at Intel)