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
23static 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
36static 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