net: dsa: bcm_sf2: fix 64-bits register reads
authorFlorian Fainelli <f.fainelli@gmail.com>
Thu, 19 Feb 2015 19:09:27 +0000 (11:09 -0800)
committerDavid S. Miller <davem@davemloft.net>
Fri, 20 Feb 2015 22:52:46 +0000 (17:52 -0500)
Reading 64-bits register was not working because we inverted the steps
between reading the lower 32-bits of the register and reading the upper
32-bits. Swapping these operations is how the HW guarantees that 64-bits
reads are latched correctly. We only have a handful of 64-bits registers
for now, mostly MIB counters, so the imapct is low.

Fixes: 246d7f773c13 ("net: dsa: add Broadcom SF2 switch driver")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
drivers/net/dsa/bcm_sf2.h

index ee9f650d50264bb74771783b65e860b2aabb3d46..7b7053d3c5fad20e07a75eb5ea987743b51484ba 100644 (file)
@@ -105,8 +105,8 @@ static inline u64 name##_readq(struct bcm_sf2_priv *priv, u32 off)  \
 {                                                                      \
        u32 indir, dir;                                                 \
        spin_lock(&priv->indir_lock);                                   \
-       indir = reg_readl(priv, REG_DIR_DATA_READ);                     \
        dir = __raw_readl(priv->name + off);                            \
+       indir = reg_readl(priv, REG_DIR_DATA_READ);                     \
        spin_unlock(&priv->indir_lock);                                 \
        return (u64)indir << 32 | dir;                                  \
 }                                                                      \