git: c637d474045a - main - igb: Stop writing the legacy TADV register

The branch main has been updated by kbowling:

URL: https://cgit.FreeBSD.org/src/commit/?id=c637d474045a41b1763c17a8b4b7763d4159504f

commit c637d474045a41b1763c17a8b4b7763d4159504f
Author:     Kevin Bowling <kbowling@FreeBSD.org>
AuthorDate: 2026-07-29 04:23:30 +0000
Commit:     Kevin Bowling <kbowling@FreeBSD.org>
CommitDate: 2026-07-30 05:05:32 +0000

    igb: Stop writing the legacy TADV register
    
    TADV is an em-class interrupt delay register and is absent from the
    82575 and later register model. The igb attach path does not expose or
    initialize that control, but transmit initialization still wrote its
    zero valued storage into a reserved queue-window offset.
    
    Apply the same igb_mac_min boundary already used for TIDV and the
    absolute-delay sysctls.
    
    MFC after:      1 week
    Sponsored by:   BBOX.io
---
 sys/dev/e1000/if_em.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sys/dev/e1000/if_em.c b/sys/dev/e1000/if_em.c
index 4f4eeee5da50..0f60178ae3c8 100644
--- a/sys/dev/e1000/if_em.c
+++ b/sys/dev/e1000/if_em.c
@@ -4208,7 +4208,7 @@ em_initialize_transmit_unit(if_ctx_t ctx)
 			sc->txd_cmd |= E1000_TXD_CMD_IDE;
 	}
 
-	if (hw->mac.type >= e1000_82540)
+	if (hw->mac.type >= e1000_82540 && hw->mac.type < igb_mac_min)
 		E1000_WRITE_REG(hw, E1000_TADV, sc->tx_abs_int_delay.value);
 
 	if (hw->mac.type == e1000_82571 || hw->mac.type == e1000_82572) {