Re: [RFC PATCH 04/10] net: dsa: b53: fix IP_MULTICAST_CTRL on BCM5325

From: Florian Fainelli
Date: Mon Jun 02 2025 - 14:06:47 EST


On 5/31/25 03:13, Álvaro Fernández Rojas wrote:
BCM5325 doesn't implement B53_UC_FWD_EN, B53_MC_FWD_EN or B53_IPMC_FWD_EN.

Fixes: 53568438e381 ("net: dsa: b53: Add support for port_egress_floods callback")
Signed-off-by: Álvaro Fernández Rojas <noltari@xxxxxxxxx>
---
drivers/net/dsa/b53/b53_common.c | 13 +++++++++----
drivers/net/dsa/b53/b53_regs.h | 1 +
2 files changed, 10 insertions(+), 4 deletions(-)

diff --git a/drivers/net/dsa/b53/b53_common.c b/drivers/net/dsa/b53/b53_common.c
index f314aeb81643..6b2ad82aa95f 100644
--- a/drivers/net/dsa/b53/b53_common.c
+++ b/drivers/net/dsa/b53/b53_common.c
@@ -367,11 +367,16 @@ static void b53_set_forwarding(struct b53_device *dev, int enable)
b53_write8(dev, B53_CTRL_PAGE, B53_SWITCH_CTRL, mgmt);
}
- /* Look at B53_UC_FWD_EN and B53_MC_FWD_EN to decide whether
- * frames should be flooded or not.
- */
b53_read8(dev, B53_CTRL_PAGE, B53_IP_MULTICAST_CTRL, &mgmt);
- mgmt |= B53_UC_FWD_EN | B53_MC_FWD_EN | B53_IPMC_FWD_EN;
+ if (is5325(dev)) {
+ /* Enable IP multicast address scheme. */
+ mgmt |= B53_IP_MCAST_25;
+ } else {
+ /* Look at B53_UC_FWD_EN and B53_MC_FWD_EN to decide whether
+ * frames should be flooded or not.
+ */
+ mgmt |= B53_UC_FWD_EN | B53_MC_FWD_EN | B53_IPMC_FWD_EN;
+ }
b53_write8(dev, B53_CTRL_PAGE, B53_IP_MULTICAST_CTRL, mgmt);

I don't think B53_IPM_MULTICAST_CTRL is a valid register offset within B53_CTRL_PAGE, or elsewhere for that matter, do you have a datasheet that says this exists?
--
Florian