From 0e6140a56f2878816ecf9db50f40133d25d987e4 Mon Sep 17 00:00:00 2001 From: Benjamin Herrenschmidt Date: Fri, 21 Dec 2007 15:39:22 +1100 Subject: [POWERPC] 4xx: Improve support for 4xx indirect DCRs Accessing indirect DCRs is done via a pair of address/data DCRs. Such accesses are thus inherently racy, vs. interrupts, preemption and possibly SMP if 4xx SMP cores are ever used. This updates the mfdcri/mtdcri macros in dcr-native.h (which were so far unused) to use a spinlock. In addition, add some common definitions to a new dcr-regs.h file. Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Josh Boyer --- include/asm-powerpc/dcr-native.h | 30 ++++++++++++++++++++---------- 1 file changed, 20 insertions(+), 10 deletions(-) (limited to 'include/asm-powerpc/dcr-native.h') diff --git a/include/asm-powerpc/dcr-native.h b/include/asm-powerpc/dcr-native.h index 8dbb1ab0aa04..af5fb31af559 100644 --- a/include/asm-powerpc/dcr-native.h +++ b/include/asm-powerpc/dcr-native.h @@ -22,6 +22,8 @@ #ifdef __KERNEL__ #ifndef __ASSEMBLY__ +#include + typedef struct { unsigned int base; } dcr_host_t; @@ -55,20 +57,28 @@ do { \ } while (0) /* R/W of indirect DCRs make use of standard naming conventions for DCRs */ -#define mfdcri(base, reg) \ -({ \ - mtdcr(base ## _CFGADDR, base ## _ ## reg); \ - mfdcr(base ## _CFGDATA); \ +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; \ }) -#define mtdcri(base, reg, data) \ -do { \ - mtdcr(base ## _CFGADDR, base ## _ ## reg); \ - mtdcr(base ## _CFGDATA, data); \ +#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) #endif /* __ASSEMBLY__ */ #endif /* __KERNEL__ */ #endif /* _ASM_POWERPC_DCR_NATIVE_H */ - - -- cgit v1.2.1