6.6-stable review patch. If anyone has any objections, please let me know.
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From: Jonas Gorski jonas.gorski@gmail.com
[ Upstream commit ca8c1f71c10193c270f772d70d34b15ad765d6a8 ]
BCM5325/BCM5365 do not support jumbo frames, so we should not report a jumbo frame mtu for them. But they do support so called "oversized" frames up to 1536 bytes long by default, so report an appropriate MTU.
Fixes: 6ae5834b983a ("net: dsa: b53: add MTU configuration support") Signed-off-by: Jonas Gorski jonas.gorski@gmail.com Reviewed-by: Florian Fainelli florian.fainelli@broadcom.com Signed-off-by: Paolo Abeni pabeni@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/dsa/b53/b53_common.c | 6 ++++++ 1 file changed, 6 insertions(+)
diff --git a/drivers/net/dsa/b53/b53_common.c b/drivers/net/dsa/b53/b53_common.c index 0a1f7f1315721..b43b414b26969 100644 --- a/drivers/net/dsa/b53/b53_common.c +++ b/drivers/net/dsa/b53/b53_common.c @@ -225,6 +225,7 @@ static const struct b53_mib_desc b53_mibs_58xx[] = {
#define B53_MIBS_58XX_SIZE ARRAY_SIZE(b53_mibs_58xx)
+#define B53_MAX_MTU_25 (1536 - ETH_HLEN - VLAN_HLEN - ETH_FCS_LEN) #define B53_MAX_MTU (9720 - ETH_HLEN - VLAN_HLEN - ETH_FCS_LEN)
static int b53_do_vlan_op(struct b53_device *dev, u8 op) @@ -2279,6 +2280,11 @@ static int b53_change_mtu(struct dsa_switch *ds, int port, int mtu)
static int b53_get_max_mtu(struct dsa_switch *ds, int port) { + struct b53_device *dev = ds->priv; + + if (is5325(dev) || is5365(dev)) + return B53_MAX_MTU_25; + return B53_MAX_MTU; }