iwlwifi: use rmb/wmb to protect indirect mmio operation
This patch protects iwlwifi indirect mmio operations with rmb() and
wmb(). It makes sure CPU reordering won't affect our indirect mmio
access.
Signed-off-by: Zhu Yi <yi.zhu@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/iwlwifi/iwl-io.h b/drivers/net/wireless/iwlwifi/iwl-io.h
index c56dc21..10ca032 100644
--- a/drivers/net/wireless/iwlwifi/iwl-io.h
+++ b/drivers/net/wireless/iwlwifi/iwl-io.h
@@ -299,6 +299,7 @@
static inline u32 _iwl_read_prph(struct iwl_priv *priv, u32 reg)
{
_iwl_write_direct32(priv, HBUS_TARG_PRPH_RADDR, reg | (3 << 24));
+ rmb();
return _iwl_read_direct32(priv, HBUS_TARG_PRPH_RDAT);
}
#ifdef CONFIG_IWLWIFI_DEBUG
@@ -321,6 +322,7 @@
{
_iwl_write_direct32(priv, HBUS_TARG_PRPH_WADDR,
((addr & 0x0000FFFF) | (3 << 24)));
+ wmb();
_iwl_write_direct32(priv, HBUS_TARG_PRPH_WDAT, val);
}
#ifdef CONFIG_IWLWIFI_DEBUG
@@ -383,12 +385,14 @@
static inline u32 iwl_read_targ_mem(struct iwl_priv *priv, u32 addr)
{
iwl_write_direct32(priv, HBUS_TARG_MEM_RADDR, addr);
+ rmb();
return iwl_read_direct32(priv, HBUS_TARG_MEM_RDAT);
}
static inline void iwl_write_targ_mem(struct iwl_priv *priv, u32 addr, u32 val)
{
iwl_write_direct32(priv, HBUS_TARG_MEM_WADDR, addr);
+ wmb();
iwl_write_direct32(priv, HBUS_TARG_MEM_WDAT, val);
}
@@ -396,6 +400,7 @@
u32 len, u32 *values)
{
iwl_write_direct32(priv, HBUS_TARG_MEM_WADDR, addr);
+ wmb();
for (; 0 < len; len -= sizeof(u32), values++)
iwl_write_direct32(priv, HBUS_TARG_MEM_WDAT, *values);
}