xref: /openbmc/linux/arch/sh/mm/cache-sh2a.c (revision 3cf3cdea)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * arch/sh/mm/cache-sh2a.c
4  *
5  * Copyright (C) 2008 Yoshinori Sato
6  */
7 
8 #include <linux/init.h>
9 #include <linux/mm.h>
10 
11 #include <asm/cache.h>
12 #include <asm/addrspace.h>
13 #include <asm/processor.h>
14 #include <asm/cacheflush.h>
15 #include <asm/io.h>
16 
17 /*
18  * The maximum number of pages we support up to when doing ranged dcache
19  * flushing. Anything exceeding this will simply flush the dcache in its
20  * entirety.
21  */
22 #define MAX_OCACHE_PAGES	32
23 #define MAX_ICACHE_PAGES	32
24 
25 #ifdef CONFIG_CACHE_WRITEBACK
26 static void sh2a_flush_oc_line(unsigned long v, int way)
27 {
28 	unsigned long addr = (v & 0x000007f0) | (way << 11);
29 	unsigned long data;
30 
31 	data = __raw_readl(CACHE_OC_ADDRESS_ARRAY | addr);
32 	if ((data & CACHE_PHYSADDR_MASK) == (v & CACHE_PHYSADDR_MASK)) {
33 		data &= ~SH_CACHE_UPDATED;
34 		__raw_writel(data, CACHE_OC_ADDRESS_ARRAY | addr);
35 	}
36 }
37 #endif
38 
39 static void sh2a_invalidate_line(unsigned long cache_addr, unsigned long v)
40 {
41 	/* Set associative bit to hit all ways */
42 	unsigned long addr = (v & 0x000007f0) | SH_CACHE_ASSOC;
43 	__raw_writel((addr & CACHE_PHYSADDR_MASK), cache_addr | addr);
44 }
45 
46 /*
47  * Write back the dirty D-caches, but not invalidate them.
48  */
49 static void sh2a__flush_wback_region(void *start, int size)
50 {
51 #ifdef CONFIG_CACHE_WRITEBACK
52 	unsigned long v;
53 	unsigned long begin, end;
54 	unsigned long flags;
55 	int nr_ways;
56 
57 	begin = (unsigned long)start & ~(L1_CACHE_BYTES-1);
58 	end = ((unsigned long)start + size + L1_CACHE_BYTES-1)
59 		& ~(L1_CACHE_BYTES-1);
60 	nr_ways = current_cpu_data.dcache.ways;
61 
62 	local_irq_save(flags);
63 	jump_to_uncached();
64 
65 	/* If there are too many pages then flush the entire cache */
66 	if (((end - begin) >> PAGE_SHIFT) >= MAX_OCACHE_PAGES) {
67 		begin = CACHE_OC_ADDRESS_ARRAY;
68 		end = begin + (nr_ways * current_cpu_data.dcache.way_size);
69 
70 		for (v = begin; v < end; v += L1_CACHE_BYTES) {
71 			unsigned long data = __raw_readl(v);
72 			if (data & SH_CACHE_UPDATED)
73 				__raw_writel(data & ~SH_CACHE_UPDATED, v);
74 		}
75 	} else {
76 		int way;
77 		for (way = 0; way < nr_ways; way++) {
78 			for (v = begin; v < end; v += L1_CACHE_BYTES)
79 				sh2a_flush_oc_line(v, way);
80 		}
81 	}
82 
83 	back_to_cached();
84 	local_irq_restore(flags);
85 #endif
86 }
87 
88 /*
89  * Write back the dirty D-caches and invalidate them.
90  */
91 static void sh2a__flush_purge_region(void *start, int size)
92 {
93 	unsigned long v;
94 	unsigned long begin, end;
95 	unsigned long flags;
96 
97 	begin = (unsigned long)start & ~(L1_CACHE_BYTES-1);
98 	end = ((unsigned long)start + size + L1_CACHE_BYTES-1)
99 		& ~(L1_CACHE_BYTES-1);
100 
101 	local_irq_save(flags);
102 	jump_to_uncached();
103 
104 	for (v = begin; v < end; v+=L1_CACHE_BYTES) {
105 #ifdef CONFIG_CACHE_WRITEBACK
106 		int way;
107 		int nr_ways = current_cpu_data.dcache.ways;
108 		for (way = 0; way < nr_ways; way++)
109 			sh2a_flush_oc_line(v, way);
110 #endif
111 		sh2a_invalidate_line(CACHE_OC_ADDRESS_ARRAY, v);
112 	}
113 
114 	back_to_cached();
115 	local_irq_restore(flags);
116 }
117 
118 /*
119  * Invalidate the D-caches, but no write back please
120  */
121 static void sh2a__flush_invalidate_region(void *start, int size)
122 {
123 	unsigned long v;
124 	unsigned long begin, end;
125 	unsigned long flags;
126 
127 	begin = (unsigned long)start & ~(L1_CACHE_BYTES-1);
128 	end = ((unsigned long)start + size + L1_CACHE_BYTES-1)
129 		& ~(L1_CACHE_BYTES-1);
130 
131 	local_irq_save(flags);
132 	jump_to_uncached();
133 
134 	/* If there are too many pages then just blow the cache */
135 	if (((end - begin) >> PAGE_SHIFT) >= MAX_OCACHE_PAGES) {
136 		__raw_writel(__raw_readl(SH_CCR) | CCR_OCACHE_INVALIDATE,
137 			     SH_CCR);
138 	} else {
139 		for (v = begin; v < end; v += L1_CACHE_BYTES)
140 			sh2a_invalidate_line(CACHE_OC_ADDRESS_ARRAY, v);
141 	}
142 
143 	back_to_cached();
144 	local_irq_restore(flags);
145 }
146 
147 /*
148  * Write back the range of D-cache, and purge the I-cache.
149  */
150 static void sh2a_flush_icache_range(void *args)
151 {
152 	struct flusher_data *data = args;
153 	unsigned long start, end;
154 	unsigned long v;
155 	unsigned long flags;
156 
157 	start = data->addr1 & ~(L1_CACHE_BYTES-1);
158 	end = (data->addr2 + L1_CACHE_BYTES-1) & ~(L1_CACHE_BYTES-1);
159 
160 #ifdef CONFIG_CACHE_WRITEBACK
161 	sh2a__flush_wback_region((void *)start, end-start);
162 #endif
163 
164 	local_irq_save(flags);
165 	jump_to_uncached();
166 
167 	/* I-Cache invalidate */
168 	/* If there are too many pages then just blow the cache */
169 	if (((end - start) >> PAGE_SHIFT) >= MAX_ICACHE_PAGES) {
170 		__raw_writel(__raw_readl(SH_CCR) | CCR_ICACHE_INVALIDATE,
171 			     SH_CCR);
172 	} else {
173 		for (v = start; v < end; v += L1_CACHE_BYTES)
174 			sh2a_invalidate_line(CACHE_IC_ADDRESS_ARRAY, v);
175 	}
176 
177 	back_to_cached();
178 	local_irq_restore(flags);
179 }
180 
181 void __init sh2a_cache_init(void)
182 {
183 	local_flush_icache_range	= sh2a_flush_icache_range;
184 
185 	__flush_wback_region		= sh2a__flush_wback_region;
186 	__flush_purge_region		= sh2a__flush_purge_region;
187 	__flush_invalidate_region	= sh2a__flush_invalidate_region;
188 }
189