linux_dsm_epyc7002/arch/powerpc/include/asm/cache.h
Nicholas Piggin f4329f2ecb powerpc/64s: Reduce exception alignment
Exception handlers are aligned to 128 bytes (L1 cache) on 64s, which is
overkill. It can reduce the icache footprint of any individual exception
path. However taken as a whole, the expansion in icache footprint seems
likely to be counter-productive and cause more total misses.

Create IFETCH_ALIGN_SHIFT/BYTES, which should give optimal ifetch
alignment with much more reasonable alignment. This saves 1792 bytes
from head_64.o text with an allmodconfig build.

Other subarchitectures should define appropriate IFETCH_ALIGN_SHIFT
values if this becomes more widely used.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-11-14 11:11:51 +11:00

97 lines
2.3 KiB
C

#ifndef _ASM_POWERPC_CACHE_H
#define _ASM_POWERPC_CACHE_H
#ifdef __KERNEL__
/* bytes per L1 cache line */
#if defined(CONFIG_8xx) || defined(CONFIG_403GCX)
#define L1_CACHE_SHIFT 4
#define MAX_COPY_PREFETCH 1
#elif defined(CONFIG_PPC_E500MC)
#define L1_CACHE_SHIFT 6
#define MAX_COPY_PREFETCH 4
#elif defined(CONFIG_PPC32)
#define MAX_COPY_PREFETCH 4
#if defined(CONFIG_PPC_47x)
#define L1_CACHE_SHIFT 7
#else
#define L1_CACHE_SHIFT 5
#endif
#else /* CONFIG_PPC64 */
#define L1_CACHE_SHIFT 7
#define IFETCH_ALIGN_SHIFT 4 /* POWER8,9 */
#endif
#define L1_CACHE_BYTES (1 << L1_CACHE_SHIFT)
#define SMP_CACHE_BYTES L1_CACHE_BYTES
#define IFETCH_ALIGN_BYTES (1 << IFETCH_ALIGN_SHIFT)
#if defined(__powerpc64__) && !defined(__ASSEMBLY__)
struct ppc64_caches {
u32 dsize; /* L1 d-cache size */
u32 dline_size; /* L1 d-cache line size */
u32 log_dline_size;
u32 dlines_per_page;
u32 isize; /* L1 i-cache size */
u32 iline_size; /* L1 i-cache line size */
u32 log_iline_size;
u32 ilines_per_page;
};
extern struct ppc64_caches ppc64_caches;
#endif /* __powerpc64__ && ! __ASSEMBLY__ */
#if defined(__ASSEMBLY__)
/*
* For a snooping icache, we still need a dummy icbi to purge all the
* prefetched instructions from the ifetch buffers. We also need a sync
* before the icbi to order the the actual stores to memory that might
* have modified instructions with the icbi.
*/
#define PURGE_PREFETCHED_INS \
sync; \
icbi 0,r3; \
sync; \
isync
#else
#define __read_mostly __attribute__((__section__(".data..read_mostly")))
#ifdef CONFIG_6xx
extern long _get_L2CR(void);
extern long _get_L3CR(void);
extern void _set_L2CR(unsigned long);
extern void _set_L3CR(unsigned long);
#else
#define _get_L2CR() 0L
#define _get_L3CR() 0L
#define _set_L2CR(val) do { } while(0)
#define _set_L3CR(val) do { } while(0)
#endif
static inline void dcbz(void *addr)
{
__asm__ __volatile__ ("dcbz 0, %0" : : "r"(addr) : "memory");
}
static inline void dcbi(void *addr)
{
__asm__ __volatile__ ("dcbi 0, %0" : : "r"(addr) : "memory");
}
static inline void dcbf(void *addr)
{
__asm__ __volatile__ ("dcbf 0, %0" : : "r"(addr) : "memory");
}
static inline void dcbst(void *addr)
{
__asm__ __volatile__ ("dcbst 0, %0" : : "r"(addr) : "memory");
}
#endif /* !__ASSEMBLY__ */
#endif /* __KERNEL__ */
#endif /* _ASM_POWERPC_CACHE_H */