pmem.c

 1// SPDX-License-Identifier: GPL-2.0-only
 2/*
 3 * Copyright(c) 2017 IBM Corporation. All rights reserved.
 4 */
 5
 6#include <linux/string.h>
 7#include <linux/export.h>
 8#include <linux/uaccess.h>
 9#include <linux/libnvdimm.h>
10
11#include <asm/cacheflush.h>
12
13static inline void __clean_pmem_range(unsigned long start, unsigned long stop)
14{
15	unsigned long shift = l1_dcache_shift();
16	unsigned long bytes = l1_dcache_bytes();
17	void *addr = (void *)(start & ~(bytes - 1));
18	unsigned long size = stop - (unsigned long)addr + (bytes - 1);
19	unsigned long i;
20
21	for (i = 0; i < size >> shift; i++, addr += bytes)
22		asm volatile(PPC_DCBSTPS(%0, %1): :"i"(0), "r"(addr): "memory");
23}
24
25static inline void __flush_pmem_range(unsigned long start, unsigned long stop)
26{
27	unsigned long shift = l1_dcache_shift();
28	unsigned long bytes = l1_dcache_bytes();
29	void *addr = (void *)(start & ~(bytes - 1));
30	unsigned long size = stop - (unsigned long)addr + (bytes - 1);
31	unsigned long i;
32
33	for (i = 0; i < size >> shift; i++, addr += bytes)
34		asm volatile(PPC_DCBFPS(%0, %1): :"i"(0), "r"(addr): "memory");
35}
36
37static inline void clean_pmem_range(unsigned long start, unsigned long stop)
38{
39	if (cpu_has_feature(CPU_FTR_ARCH_207S))
40		return __clean_pmem_range(start, stop);
41}
42
43static inline void flush_pmem_range(unsigned long start, unsigned long stop)
44{
45	if (cpu_has_feature(CPU_FTR_ARCH_207S))
46		return __flush_pmem_range(start, stop);
47}
48
49/*
50 * CONFIG_ARCH_HAS_PMEM_API symbols
51 */
52void arch_wb_cache_pmem(void *addr, size_t size)
53{
54	unsigned long start = (unsigned long) addr;
55	clean_pmem_range(start, start + size);
56}
57EXPORT_SYMBOL_GPL(arch_wb_cache_pmem);
58
59void arch_invalidate_pmem(void *addr, size_t size)
60{
61	unsigned long start = (unsigned long) addr;
62	flush_pmem_range(start, start + size);
63}
64EXPORT_SYMBOL_GPL(arch_invalidate_pmem);
65
66/*
67 * CONFIG_ARCH_HAS_UACCESS_FLUSHCACHE symbols
68 */
69size_t copy_from_user_flushcache(void *dest, const void __user *src,
70				 size_t size)
71{
72	unsigned long not_copied, start = (unsigned long) dest;
73
74	src = mask_user_address(src);
75	not_copied = __copy_from_user(dest, src, size);
76	clean_pmem_range(start, start + size);
77
78	return not_copied;
79}
80
81void memcpy_flushcache(void *dest, const void *src, size_t size)
82{
83	unsigned long start = (unsigned long) dest;
84
85	memcpy(dest, src, size);
86	clean_pmem_range(start, start + size);
87}
88EXPORT_SYMBOL(memcpy_flushcache);