The previous 7 KB per queue caused TX unit hangs under heavy
timestamping load. Reducing to 5 KB avoids these hangs and matches
the TSN recommendation in I225/I226 SW User Manual Section 7.5.4.
The 8 KB “freed” by this change is currently unused. This reduction
is not expected to impact throughput, as the i226 is PCIe-limited
for small TSN packets rather than TX-buffer-limited.
Fixes: 0d58cdc902da ("igc: optimize TX packet buffer utilization for TSN mode")
Reported-by: Zdenek Bouska <[email protected]>
Closes:
https://lore.kernel.org/netdev/as1pr10mb5675dbfe7ce5f2a9336abfa4eb...@as1pr10mb5675.eurprd10.prod.outlook.com/
Reviewed-by: Paul Menzel <[email protected]>
Reviewed-by: Simon Horman <[email protected]>
Reviewed-by: Aleksandr Loktionov <[email protected]>
Signed-off-by: Chwee-Lin Choong <[email protected]>
---
v1:
https://patchwork.ozlabs.org/project/intel-wired-lan/patch/[email protected]/
changelog:
v1 -> v2
- Elaborated commit message
---
drivers/net/ethernet/intel/igc/igc_defines.h | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/drivers/net/ethernet/intel/igc/igc_defines.h
b/drivers/net/ethernet/intel/igc/igc_defines.h
index 498ba1522ca4..9482ab11f050 100644
--- a/drivers/net/ethernet/intel/igc/igc_defines.h
+++ b/drivers/net/ethernet/intel/igc/igc_defines.h
@@ -443,9 +443,10 @@
#define IGC_TXPBSIZE_DEFAULT ( \
IGC_TXPB0SIZE(20) | IGC_TXPB1SIZE(0) | IGC_TXPB2SIZE(0) | \
IGC_TXPB3SIZE(0) | IGC_OS2BMCPBSIZE(4))
+/* TSN value following I225/I226 SW User Manual Section 7.5.4 */
#define IGC_TXPBSIZE_TSN ( \
- IGC_TXPB0SIZE(7) | IGC_TXPB1SIZE(7) | IGC_TXPB2SIZE(7) | \
- IGC_TXPB3SIZE(7) | IGC_OS2BMCPBSIZE(4))
+ IGC_TXPB0SIZE(5) | IGC_TXPB1SIZE(5) | IGC_TXPB2SIZE(5) | \
+ IGC_TXPB3SIZE(5) | IGC_OS2BMCPBSIZE(4))
#define IGC_DTXMXPKTSZ_TSN 0x19 /* 1600 bytes of max TX DMA packet size */
#define IGC_DTXMXPKTSZ_DEFAULT 0x98 /* 9728-byte Jumbo frames */
--
2.43.0
