[PATCH 3.16 021/306] net: systemport: Fix ordering in intrl2_*_mask_clear macro

From: Ben Hutchings
Date: Wed Feb 15 2017 - 18:58:44 EST


3.16.40-rc1 review patch. If anyone has any objections, please let me know.

------------------

From: Florian Fainelli <f.fainelli@xxxxxxxxx>

commit 9a0a5c4cb1af98b625dcefd72e987ca4929db71d upstream.

Since we keep shadow copies of which interrupt sources are enabled
through the intrl2_*_mask_{set,clear} macros, make sure that the
ordering in which we do these two operations: update the copy, then
unmask the register is correct.

This is not currently a problem because we actually do not use them, but
we will in a subsequent patch optimizing register accesses, so better be
safe here.

Fixes: 80105befdb4b ("net: systemport: add Broadcom SYSTEMPORT Ethernet MAC driver")
Signed-off-by: Florian Fainelli <f.fainelli@xxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
drivers/net/ethernet/broadcom/bcmsysport.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/net/ethernet/broadcom/bcmsysport.c
+++ b/drivers/net/ethernet/broadcom/bcmsysport.c
@@ -58,8 +58,8 @@ BCM_SYSPORT_IO_MACRO(topctrl, SYS_PORT_T
static inline void intrl2_##which##_mask_clear(struct bcm_sysport_priv *priv, \
u32 mask) \
{ \
- intrl2_##which##_writel(priv, mask, INTRL2_CPU_MASK_CLEAR); \
priv->irq##which##_mask &= ~(mask); \
+ intrl2_##which##_writel(priv, mask, INTRL2_CPU_MASK_CLEAR); \
} \
static inline void intrl2_##which##_mask_set(struct bcm_sysport_priv *priv, \
u32 mask) \