While investigating the capabilities of BCM63XX's integrated switch and
its DMA engine, I noticed a few issues in b53's jumbo frame code.

Mostly a confusion of MTU vs frame length, but also a few missing cases
for 100M switches.

Tested on BCM63XX and BCM53115 with intel 1G and realtek 1G NICs,
which support MTUs of 9000 or slightly above, but significantly less
than the 9716/9720 supported by BCM53115, so I couldn't verify the
actual maximum frame length.

Signed-off-by: Jonas Gorski <jonas.gorski@gmail.com>
---
Jonas Gorski (5):
      net: dsa: b53: fix jumbo frame mtu check
      net: dsa: b53: fix max MTU for 1g switches
      net: dsa: b53: fix max MTU for BCM5325/BCM5365
      net: dsa: b53: allow lower MTUs on BCM5325/5365
      net: dsa: b53: fix jumbo frames on 10/100 ports

 drivers/net/dsa/b53/b53_common.c | 17 +++++++++++++----
 1 file changed, 13 insertions(+), 4 deletions(-)
---
base-commit: 8beee4d8dee76b67c75dc91fd8185d91e845c160
change-id: 20241003-b53_jumbo_fixes-95ff690b1d9e

Best regards,
-- 
Jonas Gorski <jonas.gorski@gmail.com>