[POWERPC] 4xx: PCIe indirect DCR spinlock fix.

Since we have mfdcri() and mtdcri() as macros, we can't use constructions,
such as "mtdcri(base, reg, mfdcri(base, reg) | val)".  In this case the
mfdcri() stuff is not evaluated first.  It's evaluated inside the mtdcri()
macro and we have the dcr_ind_lock spinlock acquired twice.

To avoid this error, I've added __mfdcri()/__mtdcri() inline functions that
take the lock after register name fix-up.

Signed-off-by: Valentine Barshak <vbarshak@ru.mvista.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>

diff --git a/include/asm-powerpc/dcr-native.h b/include/asm-powerpc/dcr-native.h
index af5fb31..be6c879 100644 (file)
--- a/include/asm-powerpc/dcr-native.h
+++ b/include/asm-powerpc/dcr-native.h
@@ -59,25 +59,36 @@ do {                                                                \
 /* R/W of indirect DCRs make use of standard naming conventions for DCRs */
 extern spinlock_t dcr_ind_lock;
 
-#define mfdcri(base, reg)                              \
-({                                                     \
-       unsigned long flags;                            \
-       unsigned int val;                               \
-       spin_lock_irqsave(&dcr_ind_lock, flags);        \
-       mtdcr(DCRN_ ## base ## _CONFIG_ADDR, reg);      \
-       val = mfdcr(DCRN_ ## base ## _CONFIG_DATA);     \
-       spin_unlock_irqrestore(&dcr_ind_lock, flags);   \
-       val;                                            \
-})
+static inline unsigned __mfdcri(int base_addr, int base_data, int reg)
+{
+       unsigned long flags;
+       unsigned int val;
 
-#define mtdcri(base, reg, data)                                \
-do {                                                   \
-       unsigned long flags;                            \
-       spin_lock_irqsave(&dcr_ind_lock, flags);        \
-       mtdcr(DCRN_ ## base ## _CONFIG_ADDR, reg);      \
-       mtdcr(DCRN_ ## base ## _CONFIG_DATA, data);     \
-       spin_unlock_irqrestore(&dcr_ind_lock, flags);   \
-} while (0)
+       spin_lock_irqsave(&dcr_ind_lock, flags);
+       __mtdcr(base_addr, reg);
+       val = __mfdcr(base_data);
+       spin_unlock_irqrestore(&dcr_ind_lock, flags);
+       return val;
+}
+
+static inline void __mtdcri(int base_addr, int base_data, int reg,
+                           unsigned val)
+{
+       unsigned long flags;
+
+       spin_lock_irqsave(&dcr_ind_lock, flags);
+       __mtdcr(base_addr, reg);
+       __mtdcr(base_data, val);
+       spin_unlock_irqrestore(&dcr_ind_lock, flags);
+}
+
+#define mfdcri(base, reg)      __mfdcri(DCRN_ ## base ## _CONFIG_ADDR, \
+                                        DCRN_ ## base ## _CONFIG_DATA, \
+                                        reg)
+
+#define mtdcri(base, reg, data)        __mtdcri(DCRN_ ## base ## _CONFIG_ADDR, \
+                                        DCRN_ ## base ## _CONFIG_DATA, \
+                                        reg, data)
 
 #endif /* __ASSEMBLY__ */
 #endif /* __KERNEL__ */