diff options
Diffstat (limited to 'include/asm-parisc/system.h')
| -rw-r--r-- | include/asm-parisc/system.h | 31 |
1 files changed, 24 insertions, 7 deletions
diff --git a/include/asm-parisc/system.h b/include/asm-parisc/system.h index a25e9dcd2e79..f3928d3a80cb 100644 --- a/include/asm-parisc/system.h +++ b/include/asm-parisc/system.h @@ -138,13 +138,7 @@ static inline void set_eiem(unsigned long val) #define set_wmb(var, value) do { var = value; wmb(); } while (0) -/* LDCW, the only atomic read-write operation PA-RISC has. *sigh*. */ -#define __ldcw(a) ({ \ - unsigned __ret; \ - __asm__ __volatile__("ldcw 0(%1),%0" : "=r" (__ret) : "r" (a)); \ - __ret; \ -}) - +#ifndef CONFIG_PA20 /* Because kmalloc only guarantees 8-byte alignment for kmalloc'd data, and GCC only guarantees 8-byte alignment for stack locals, we can't be assured of 16-byte alignment for atomic lock data even if we @@ -152,12 +146,35 @@ static inline void set_eiem(unsigned long val) we use a struct containing an array of four ints for the atomic lock type and dynamically select the 16-byte aligned int from the array for the semaphore. */ + #define __PA_LDCW_ALIGNMENT 16 #define __ldcw_align(a) ({ \ unsigned long __ret = (unsigned long) &(a)->lock[0]; \ __ret = (__ret + __PA_LDCW_ALIGNMENT - 1) & ~(__PA_LDCW_ALIGNMENT - 1); \ (volatile unsigned int *) __ret; \ }) +#define LDCW "ldcw" + +#else /*CONFIG_PA20*/ +/* From: "Jim Hull" <jim.hull of hp.com> + I've attached a summary of the change, but basically, for PA 2.0, as + long as the ",CO" (coherent operation) completer is specified, then the + 16-byte alignment requirement for ldcw and ldcd is relaxed, and instead + they only require "natural" alignment (4-byte for ldcw, 8-byte for + ldcd). */ + +#define __PA_LDCW_ALIGNMENT 4 +#define __ldcw_align(a) ((volatile unsigned int *)a) +#define LDCW "ldcw,co" + +#endif /*!CONFIG_PA20*/ + +/* LDCW, the only atomic read-write operation PA-RISC has. *sigh*. */ +#define __ldcw(a) ({ \ + unsigned __ret; \ + __asm__ __volatile__(LDCW " 0(%1),%0" : "=r" (__ret) : "r" (a)); \ + __ret; \ +}) #ifdef CONFIG_SMP # define __lock_aligned __attribute__((__section__(".data.lock_aligned"))) |