net: bgmac: postpone turning IRQs off to avoid SoC hangs

Turning IRQs off is done by accessing Ethernet controller registers.
That can't be done until device's clock is enabled. It results in a SoC
hang otherwise.

This bug remained unnoticed for years as most bootloaders keep all
Ethernet interfaces turned on. It seems to only affect a niche SoC
family BCM47189. It has two Ethernet controllers but CFE bootloader uses
only the first one.

Fixes: 34322615cbaa ("net: bgmac: Mask interrupts during probe")
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Reviewed-by: Michal Kubiak <michal.kubiak@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/broadcom/bgmac.c b/drivers/net/ethernet/broadcom/bgmac.c
index 1761df8..10c7c23 100644 (file)
--- a/drivers/net/ethernet/broadcom/bgmac.c
+++ b/drivers/net/ethernet/broadcom/bgmac.c
@@ -1492,8 +1492,6 @@ int bgmac_enet_probe(struct bgmac *bgmac)
 
        bgmac->in_init = true;
 
-       bgmac_chip_intrs_off(bgmac);
-
        net_dev->irq = bgmac->irq;
        SET_NETDEV_DEV(net_dev, bgmac->dev);
        dev_set_drvdata(bgmac->dev, bgmac);
@@ -1511,6 +1509,8 @@ int bgmac_enet_probe(struct bgmac *bgmac)
         */
        bgmac_clk_enable(bgmac, 0);
 
+       bgmac_chip_intrs_off(bgmac);
+
        /* This seems to be fixing IRQ by assigning OOB #6 to the core */
        if (!(bgmac->feature_flags & BGMAC_FEAT_IDM_MASK)) {
                if (bgmac->feature_flags & BGMAC_FEAT_IRQ_ID_OOB_6)