[PATCH iwl-net] i40e: Fix max frame size check

From: Ivan Vecera
Date: Wed Nov 08 2023 - 10:11:24 EST


Commit 3a2c6ced90e1 ("i40e: Add a check to see if MFS is set") added
a check for port's MFS (max frame size) value. The value is stored
in PRTGL_SAH register for each physical port. According datasheet this
register is defined as:

PRTGL_SAH[PRT]: (0x001E2140 + 0x4*PRT, PRT=0...3)

where PRT is physical port number.

The existing check does not take port number into account and reads
actually MFS value always for port 0 that is correct for PF 0 but
not for other PFs.

Update PRTGL_SAH register definition so it takes a port number as
an argument and fix the check by passing the port number.
Also fix the warning message that use for a port number a local
variable 'i' that really does not contain such information.

Fixes: 3a2c6ced90e1 ("i40e: Add a check to see if MFS is set")
Cc: Todd Fujinaka <todd.fujinaka@xxxxxxxxx>
Signed-off-by: Ivan Vecera <ivecera@xxxxxxxxxx>
---
drivers/net/ethernet/intel/i40e/i40e_main.c | 4 ++--
drivers/net/ethernet/intel/i40e/i40e_register.h | 2 +-
2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c b/drivers/net/ethernet/intel/i40e/i40e_main.c
index 4f445f6835de..6a2907674583 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_main.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_main.c
@@ -16219,11 +16219,11 @@ static int i40e_probe(struct pci_dev *pdev, const struct pci_device_id *ent)

/* make sure the MFS hasn't been set lower than the default */
#define MAX_FRAME_SIZE_DEFAULT 0x2600
- val = (rd32(&pf->hw, I40E_PRTGL_SAH) &
+ val = (rd32(&pf->hw, I40E_PRTGL_SAH(pf->hw.port)) &
I40E_PRTGL_SAH_MFS_MASK) >> I40E_PRTGL_SAH_MFS_SHIFT;
if (val < MAX_FRAME_SIZE_DEFAULT)
dev_warn(&pdev->dev, "MFS for port %x has been set below the default: %x\n",
- i, val);
+ pf->hw.port, val);

/* Add a filter to drop all Flow control frames from any VSI from being
* transmitted. By doing so we stop a malicious VF from sending out
diff --git a/drivers/net/ethernet/intel/i40e/i40e_register.h b/drivers/net/ethernet/intel/i40e/i40e_register.h
index f408fcf23ce8..75edfe3d43f7 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_register.h
+++ b/drivers/net/ethernet/intel/i40e/i40e_register.h
@@ -498,7 +498,7 @@
#define I40E_VSILAN_QBASE_VSIQTABLE_ENA_SHIFT 11
#define I40E_VSILAN_QBASE_VSIQTABLE_ENA_MASK I40E_MASK(0x1, I40E_VSILAN_QBASE_VSIQTABLE_ENA_SHIFT)
#define I40E_VSILAN_QTABLE(_i, _VSI) (0x00200000 + ((_i) * 2048 + (_VSI) * 4)) /* _i=0...7, _VSI=0...383 */ /* Reset: PFR */
-#define I40E_PRTGL_SAH 0x001E2140 /* Reset: GLOBR */
+#define I40E_PRTGL_SAH(_PRT) (0x001E2140 + ((_PRT) * 4)) /* _PRT=0...3 */ /* Reset: GLOBR */
#define I40E_PRTGL_SAH_FC_SAH_SHIFT 0
#define I40E_PRTGL_SAH_FC_SAH_MASK I40E_MASK(0xFFFF, I40E_PRTGL_SAH_FC_SAH_SHIFT)
#define I40E_PRTGL_SAH_MFS_SHIFT 16
--
2.41.0