xref: /openbmc/linux/arch/arm/mm/cache-xsc3l2.c (revision 827634ad)
1 /*
2  * arch/arm/mm/cache-xsc3l2.c - XScale3 L2 cache controller support
3  *
4  * Copyright (C) 2007 ARM Limited
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program; if not, write to the Free Software
17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18  */
19 #include <linux/init.h>
20 #include <linux/highmem.h>
21 #include <asm/cp15.h>
22 #include <asm/cputype.h>
23 #include <asm/cacheflush.h>
24 
25 #define CR_L2	(1 << 26)
26 
27 #define CACHE_LINE_SIZE		32
28 #define CACHE_LINE_SHIFT	5
29 #define CACHE_WAY_PER_SET	8
30 
31 #define CACHE_WAY_SIZE(l2ctype)	(8192 << (((l2ctype) >> 8) & 0xf))
32 #define CACHE_SET_SIZE(l2ctype)	(CACHE_WAY_SIZE(l2ctype) >> CACHE_LINE_SHIFT)
33 
34 static inline int xsc3_l2_present(void)
35 {
36 	unsigned long l2ctype;
37 
38 	__asm__("mrc p15, 1, %0, c0, c0, 1" : "=r" (l2ctype));
39 
40 	return !!(l2ctype & 0xf8);
41 }
42 
43 static inline void xsc3_l2_clean_mva(unsigned long addr)
44 {
45 	__asm__("mcr p15, 1, %0, c7, c11, 1" : : "r" (addr));
46 }
47 
48 static inline void xsc3_l2_inv_mva(unsigned long addr)
49 {
50 	__asm__("mcr p15, 1, %0, c7, c7, 1" : : "r" (addr));
51 }
52 
53 static inline void xsc3_l2_inv_all(void)
54 {
55 	unsigned long l2ctype, set_way;
56 	int set, way;
57 
58 	__asm__("mrc p15, 1, %0, c0, c0, 1" : "=r" (l2ctype));
59 
60 	for (set = 0; set < CACHE_SET_SIZE(l2ctype); set++) {
61 		for (way = 0; way < CACHE_WAY_PER_SET; way++) {
62 			set_way = (way << 29) | (set << 5);
63 			__asm__("mcr p15, 1, %0, c7, c11, 2" : : "r"(set_way));
64 		}
65 	}
66 
67 	dsb();
68 }
69 
70 static inline void l2_unmap_va(unsigned long va)
71 {
72 #ifdef CONFIG_HIGHMEM
73 	if (va != -1)
74 		kunmap_atomic((void *)va);
75 #endif
76 }
77 
78 static inline unsigned long l2_map_va(unsigned long pa, unsigned long prev_va)
79 {
80 #ifdef CONFIG_HIGHMEM
81 	unsigned long va = prev_va & PAGE_MASK;
82 	unsigned long pa_offset = pa << (32 - PAGE_SHIFT);
83 	if (unlikely(pa_offset < (prev_va << (32 - PAGE_SHIFT)))) {
84 		/*
85 		 * Switching to a new page.  Because cache ops are
86 		 * using virtual addresses only, we must put a mapping
87 		 * in place for it.
88 		 */
89 		l2_unmap_va(prev_va);
90 		va = (unsigned long)kmap_atomic_pfn(pa >> PAGE_SHIFT);
91 	}
92 	return va + (pa_offset >> (32 - PAGE_SHIFT));
93 #else
94 	return __phys_to_virt(pa);
95 #endif
96 }
97 
98 static void xsc3_l2_inv_range(unsigned long start, unsigned long end)
99 {
100 	unsigned long vaddr;
101 
102 	if (start == 0 && end == -1ul) {
103 		xsc3_l2_inv_all();
104 		return;
105 	}
106 
107 	vaddr = -1;  /* to force the first mapping */
108 
109 	/*
110 	 * Clean and invalidate partial first cache line.
111 	 */
112 	if (start & (CACHE_LINE_SIZE - 1)) {
113 		vaddr = l2_map_va(start & ~(CACHE_LINE_SIZE - 1), vaddr);
114 		xsc3_l2_clean_mva(vaddr);
115 		xsc3_l2_inv_mva(vaddr);
116 		start = (start | (CACHE_LINE_SIZE - 1)) + 1;
117 	}
118 
119 	/*
120 	 * Invalidate all full cache lines between 'start' and 'end'.
121 	 */
122 	while (start < (end & ~(CACHE_LINE_SIZE - 1))) {
123 		vaddr = l2_map_va(start, vaddr);
124 		xsc3_l2_inv_mva(vaddr);
125 		start += CACHE_LINE_SIZE;
126 	}
127 
128 	/*
129 	 * Clean and invalidate partial last cache line.
130 	 */
131 	if (start < end) {
132 		vaddr = l2_map_va(start, vaddr);
133 		xsc3_l2_clean_mva(vaddr);
134 		xsc3_l2_inv_mva(vaddr);
135 	}
136 
137 	l2_unmap_va(vaddr);
138 
139 	dsb();
140 }
141 
142 static void xsc3_l2_clean_range(unsigned long start, unsigned long end)
143 {
144 	unsigned long vaddr;
145 
146 	vaddr = -1;  /* to force the first mapping */
147 
148 	start &= ~(CACHE_LINE_SIZE - 1);
149 	while (start < end) {
150 		vaddr = l2_map_va(start, vaddr);
151 		xsc3_l2_clean_mva(vaddr);
152 		start += CACHE_LINE_SIZE;
153 	}
154 
155 	l2_unmap_va(vaddr);
156 
157 	dsb();
158 }
159 
160 /*
161  * optimize L2 flush all operation by set/way format
162  */
163 static inline void xsc3_l2_flush_all(void)
164 {
165 	unsigned long l2ctype, set_way;
166 	int set, way;
167 
168 	__asm__("mrc p15, 1, %0, c0, c0, 1" : "=r" (l2ctype));
169 
170 	for (set = 0; set < CACHE_SET_SIZE(l2ctype); set++) {
171 		for (way = 0; way < CACHE_WAY_PER_SET; way++) {
172 			set_way = (way << 29) | (set << 5);
173 			__asm__("mcr p15, 1, %0, c7, c15, 2" : : "r"(set_way));
174 		}
175 	}
176 
177 	dsb();
178 }
179 
180 static void xsc3_l2_flush_range(unsigned long start, unsigned long end)
181 {
182 	unsigned long vaddr;
183 
184 	if (start == 0 && end == -1ul) {
185 		xsc3_l2_flush_all();
186 		return;
187 	}
188 
189 	vaddr = -1;  /* to force the first mapping */
190 
191 	start &= ~(CACHE_LINE_SIZE - 1);
192 	while (start < end) {
193 		vaddr = l2_map_va(start, vaddr);
194 		xsc3_l2_clean_mva(vaddr);
195 		xsc3_l2_inv_mva(vaddr);
196 		start += CACHE_LINE_SIZE;
197 	}
198 
199 	l2_unmap_va(vaddr);
200 
201 	dsb();
202 }
203 
204 static int __init xsc3_l2_init(void)
205 {
206 	if (!cpu_is_xsc3() || !xsc3_l2_present())
207 		return 0;
208 
209 	if (get_cr() & CR_L2) {
210 		pr_info("XScale3 L2 cache enabled.\n");
211 		xsc3_l2_inv_all();
212 
213 		outer_cache.inv_range = xsc3_l2_inv_range;
214 		outer_cache.clean_range = xsc3_l2_clean_range;
215 		outer_cache.flush_range = xsc3_l2_flush_range;
216 	}
217 
218 	return 0;
219 }
220 core_initcall(xsc3_l2_init);
221