[PATCH 6.12 242/244] net: bcmasp: Restore programming of TX map vector register

Greg Kroah-Hartman
2026-03-31T16:56:34Z

From: Florian Fainelli <florian.fainelli@broadcom.com>

commit 18ff09c1b94fa1584b31d3f4e9eecdca29230ce5 upstream.

On ASP versions v2.x we need to program the TX map vector register to
properly exercise end-to-end flow control, otherwise the TX engine can
either lock-up, or cause the hardware calculated checksum to be
wrong/corrupted when multiple back to back packets are being submitted
for transmission. This register defaults to 0, which means no flow
control being applied.

Fixes: e9f31435ee7d ("net: bcmasp: Add support for asp-v3.0")
Signed-off-by: Florian Fainelli <florian.fainelli@broadcom.com>
Link: https://patch.msgid.link/20250718212242.3447751-1-florian.fainelli@broadcom.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/net/ethernet/broadcom/asp2/bcmasp_intf.c | 3 +++
1 file changed, 3 insertions(+)

--- a/drivers/net/ethernet/broadcom/asp2/bcmasp_intf.c
+++ b/drivers/net/ethernet/broadcom/asp2/bcmasp_intf.c
@@ -815,6 +815,9 @@ static void bcmasp_init_tx(struct bcmasp
/* Tx SPB */
tx_spb_ctrl_wl(intf, ((intf->channel + 8) << TX_SPB_CTRL_XF_BID_SHIFT),
TX_SPB_CTRL_XF_CTRL2);
+
+ if (intf->parent->tx_chan_offset)
+ tx_pause_ctrl_wl(intf, (1 << (intf->channel + 8)), TX_PAUSE_MAP_VECTOR);
tx_spb_top_wl(intf, 0x1e, TX_SPB_TOP_BLKOUT);

tx_spb_dma_wq(intf, intf->tx_spb_dma_addr, TX_SPB_DMA_READ);