Commit e8318d98 authored by Valentine Barshak's avatar Valentine Barshak Committed by Josh Boyer
Browse files

[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: default avatarValentine Barshak <vbarshak@ru.mvista.com>
Acked-by: default avatarBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: default avatarJosh Boyer <jwboyer@linux.vnet.ibm.com>
parent 853265e5

include/asm-powerpc/dcr-native.h

+29 −18
Original line number Diff line number Diff line
@@ -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__ */

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