system/freebsd-src
system/freebsd-src
1
0
Fork 0
mirror of https://github.com/freebsd/freebsd-src synced 2024-07-22 10:48:02 +00:00
Code Issues Actions 2 Packages Projects Releases Wiki Activity

axge: Skip dummy packet headers

Browse source 
Newer versions of the AX88179 interweave dummies alongside valid
packet headers in bulk IN transfer data. This was probably done for
backward compatibility with existing drivers.

However current driver records these dummy headers as dropped frames,
leading to stats misreporting one Ierr per Ipkt.

This skips those dummy headers silently, thereby not generating Ierrs
for them.

Reviewed by:	emaste
Pull Request:	https://github.com/freebsd/freebsd-src/pull/842
This commit is contained in:
Damien Broka 2023-09-13 09:23:47 +01:00 committed by Ed Maste
parent bb56b36d71
commit 70fbcd451b
1 changed files with 18 additions and 1 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

19
sys/dev/usb/net/if_axge.c
View file

@ -959,8 +959,16 @@ axge_rx_frame(struct usb_ether *ue, struct usb_page_cache *pc, int actlen)
hdr_off = pkt_end = (rxhdr >> 16) & 0xFFFF;
/*
* On older firmware:
* <----------------------- actlen ------------------------>
* [frame #0]...[frame #N][pkt_hdr #0]...[pkt_hdr #N][rxhdr]
*
* On newer firmware:
* <----------------------- actlen -----------------
* [frame #0]...[frame #N][pkt_hdr #0][dummy_hdr]...
* -------------------------------->
* ...[pkt_hdr #N][dummy_hdr][rxhdr]
*
* Each RX frame would be aligned on 8 bytes boundary. If
* RCR_IPE bit is set in AXGE_RCR register, there would be 2
* padding bytes and 6 dummy bytes(as the padding also should
@ -968,6 +976,10 @@ axge_rx_frame(struct usb_ether *ue, struct usb_page_cache *pc, int actlen)
* IP header on 32bits boundary. Driver don't set RCR_IPE bit
* of AXGE_RCR register, so there should be no padding bytes
* which simplifies RX logic a lot.
*
* Further, newer firmware interweaves dummy headers that have
* pktlen == 0 and should be skipped without being seen as
* dropped frames.
*/
while (pkt_cnt--) {
/* verify the header offset */
@ -978,6 +990,12 @@ axge_rx_frame(struct usb_ether *ue, struct usb_page_cache *pc, int actlen)
usbd_copy_out(pc, hdr_off, &pkt_hdr, sizeof(pkt_hdr));
pkt_hdr.status = le32toh(pkt_hdr.status);
pktlen = AXGE_RXBYTES(pkt_hdr.status);
hdr_off += sizeof(pkt_hdr);
/* Skip dummy packet header. */
if (pktlen == 0)
continue;
if (pos + pktlen > pkt_end) {
DPRINTF("Data position reached end\n");
break;
@ -989,7 +1007,6 @@ axge_rx_frame(struct usb_ether *ue, struct usb_page_cache *pc, int actlen)
} else
axge_rxeof(ue, pc, pos, pktlen, pkt_hdr.status);
pos += (pktlen + 7) & ~7;
hdr_off += sizeof(pkt_hdr);
}
}