android_kernel_motorola_sm6225/include/asm-powerpc/dcr-native.h
Valentine Barshak e8318d98e9 [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>
2008-02-06 21:02:57 -06:00

95 lines
2.8 KiB
C

/*
* (c) Copyright 2006 Benjamin Herrenschmidt, IBM Corp.
* <benh@kernel.crashing.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
* the GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#ifndef _ASM_POWERPC_DCR_NATIVE_H
#define _ASM_POWERPC_DCR_NATIVE_H
#ifdef __KERNEL__
#ifndef __ASSEMBLY__
#include <linux/spinlock.h>
typedef struct {
unsigned int base;
} dcr_host_t;
#define DCR_MAP_OK(host) (1)
#define dcr_map(dev, dcr_n, dcr_c) ((dcr_host_t){ .base = (dcr_n) })
#define dcr_unmap(host, dcr_c) do {} while (0)
#define dcr_read(host, dcr_n) mfdcr(dcr_n + host.base)
#define dcr_write(host, dcr_n, value) mtdcr(dcr_n + host.base, value)
/* Device Control Registers */
void __mtdcr(int reg, unsigned int val);
unsigned int __mfdcr(int reg);
#define mfdcr(rn) \
({unsigned int rval; \
if (__builtin_constant_p(rn)) \
asm volatile("mfdcr %0," __stringify(rn) \
: "=r" (rval)); \
else \
rval = __mfdcr(rn); \
rval;})
#define mtdcr(rn, v) \
do { \
if (__builtin_constant_p(rn)) \
asm volatile("mtdcr " __stringify(rn) ",%0" \
: : "r" (v)); \
else \
__mtdcr(rn, v); \
} while (0)
/* R/W of indirect DCRs make use of standard naming conventions for DCRs */
extern spinlock_t dcr_ind_lock;
static inline unsigned __mfdcri(int base_addr, int base_data, int reg)
{
unsigned long flags;
unsigned int val;
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__ */
#endif /* _ASM_POWERPC_DCR_NATIVE_H */