1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * include/asm-parisc/prefetch.h 4 * 5 * PA 2.0 defines data prefetch instructions on page 6-11 of the Kane book. 6 * In addition, many implementations do hardware prefetching of both 7 * instructions and data. 8 * 9 * PA7300LC (page 14-4 of the ERS) also implements prefetching by a load 10 * to gr0 but not in a way that Linux can use. If the load would cause an 11 * interruption (eg due to prefetching 0), it is suppressed on PA2.0 12 * processors, but not on 7300LC. 13 * 14 */ 15 16 #ifndef __ASM_PARISC_PREFETCH_H 17 #define __ASM_PARISC_PREFETCH_H 18 19 #ifndef __ASSEMBLY__ 20 #ifdef CONFIG_PREFETCH 21 22 #define ARCH_HAS_PREFETCH 23 static inline void prefetch(const void *addr) 24 { 25 __asm__( 26 #ifndef CONFIG_PA20 27 /* Need to avoid prefetch of NULL on PA7300LC */ 28 " extrw,u,= %0,31,32,%%r0\n" 29 #endif 30 " ldw 0(%0), %%r0" : : "r" (addr)); 31 } 32 33 /* LDD is a PA2.0 addition. */ 34 #ifdef CONFIG_PA20 35 #define ARCH_HAS_PREFETCHW 36 static inline void prefetchw(const void *addr) 37 { 38 __asm__("ldd 0(%0), %%r0" : : "r" (addr)); 39 } 40 #endif /* CONFIG_PA20 */ 41 42 #endif /* CONFIG_PREFETCH */ 43 #endif /* __ASSEMBLY__ */ 44 45 #endif /* __ASM_PARISC_PROCESSOR_H */ 46