xref: /openbmc/linux/arch/arm/mm/cache-xsc3l2.c (revision 2cf1c348)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * arch/arm/mm/cache-xsc3l2.c - XScale3 L2 cache controller support
4  *
5  * Copyright (C) 2007 ARM Limited
6  */
7 #include <linux/init.h>
8 #include <linux/highmem.h>
9 #include <asm/cp15.h>
10 #include <asm/cputype.h>
11 #include <asm/cacheflush.h>
12 
13 #define CR_L2	(1 << 26)
14 
15 #define CACHE_LINE_SIZE		32
16 #define CACHE_LINE_SHIFT	5
17 #define CACHE_WAY_PER_SET	8
18 
19 #define CACHE_WAY_SIZE(l2ctype)	(8192 << (((l2ctype) >> 8) & 0xf))
20 #define CACHE_SET_SIZE(l2ctype)	(CACHE_WAY_SIZE(l2ctype) >> CACHE_LINE_SHIFT)
21 
22 static inline int xsc3_l2_present(void)
23 {
24 	unsigned long l2ctype;
25 
26 	__asm__("mrc p15, 1, %0, c0, c0, 1" : "=r" (l2ctype));
27 
28 	return !!(l2ctype & 0xf8);
29 }
30 
31 static inline void xsc3_l2_clean_mva(unsigned long addr)
32 {
33 	__asm__("mcr p15, 1, %0, c7, c11, 1" : : "r" (addr));
34 }
35 
36 static inline void xsc3_l2_inv_mva(unsigned long addr)
37 {
38 	__asm__("mcr p15, 1, %0, c7, c7, 1" : : "r" (addr));
39 }
40 
41 static inline void xsc3_l2_inv_all(void)
42 {
43 	unsigned long l2ctype, set_way;
44 	int set, way;
45 
46 	__asm__("mrc p15, 1, %0, c0, c0, 1" : "=r" (l2ctype));
47 
48 	for (set = 0; set < CACHE_SET_SIZE(l2ctype); set++) {
49 		for (way = 0; way < CACHE_WAY_PER_SET; way++) {
50 			set_way = (way << 29) | (set << 5);
51 			__asm__("mcr p15, 1, %0, c7, c11, 2" : : "r"(set_way));
52 		}
53 	}
54 
55 	dsb();
56 }
57 
58 static inline void l2_unmap_va(unsigned long va)
59 {
60 #ifdef CONFIG_HIGHMEM
61 	if (va != -1)
62 		kunmap_atomic((void *)va);
63 #endif
64 }
65 
66 static inline unsigned long l2_map_va(unsigned long pa, unsigned long prev_va)
67 {
68 #ifdef CONFIG_HIGHMEM
69 	unsigned long va = prev_va & PAGE_MASK;
70 	unsigned long pa_offset = pa << (32 - PAGE_SHIFT);
71 	if (unlikely(pa_offset < (prev_va << (32 - PAGE_SHIFT)))) {
72 		/*
73 		 * Switching to a new page.  Because cache ops are
74 		 * using virtual addresses only, we must put a mapping
75 		 * in place for it.
76 		 */
77 		l2_unmap_va(prev_va);
78 		va = (unsigned long)kmap_atomic_pfn(pa >> PAGE_SHIFT);
79 	}
80 	return va + (pa_offset >> (32 - PAGE_SHIFT));
81 #else
82 	return __phys_to_virt(pa);
83 #endif
84 }
85 
86 static void xsc3_l2_inv_range(unsigned long start, unsigned long end)
87 {
88 	unsigned long vaddr;
89 
90 	if (start == 0 && end == -1ul) {
91 		xsc3_l2_inv_all();
92 		return;
93 	}
94 
95 	vaddr = -1;  /* to force the first mapping */
96 
97 	/*
98 	 * Clean and invalidate partial first cache line.
99 	 */
100 	if (start & (CACHE_LINE_SIZE - 1)) {
101 		vaddr = l2_map_va(start & ~(CACHE_LINE_SIZE - 1), vaddr);
102 		xsc3_l2_clean_mva(vaddr);
103 		xsc3_l2_inv_mva(vaddr);
104 		start = (start | (CACHE_LINE_SIZE - 1)) + 1;
105 	}
106 
107 	/*
108 	 * Invalidate all full cache lines between 'start' and 'end'.
109 	 */
110 	while (start < (end & ~(CACHE_LINE_SIZE - 1))) {
111 		vaddr = l2_map_va(start, vaddr);
112 		xsc3_l2_inv_mva(vaddr);
113 		start += CACHE_LINE_SIZE;
114 	}
115 
116 	/*
117 	 * Clean and invalidate partial last cache line.
118 	 */
119 	if (start < end) {
120 		vaddr = l2_map_va(start, vaddr);
121 		xsc3_l2_clean_mva(vaddr);
122 		xsc3_l2_inv_mva(vaddr);
123 	}
124 
125 	l2_unmap_va(vaddr);
126 
127 	dsb();
128 }
129 
130 static void xsc3_l2_clean_range(unsigned long start, unsigned long end)
131 {
132 	unsigned long vaddr;
133 
134 	vaddr = -1;  /* to force the first mapping */
135 
136 	start &= ~(CACHE_LINE_SIZE - 1);
137 	while (start < end) {
138 		vaddr = l2_map_va(start, vaddr);
139 		xsc3_l2_clean_mva(vaddr);
140 		start += CACHE_LINE_SIZE;
141 	}
142 
143 	l2_unmap_va(vaddr);
144 
145 	dsb();
146 }
147 
148 /*
149  * optimize L2 flush all operation by set/way format
150  */
151 static inline void xsc3_l2_flush_all(void)
152 {
153 	unsigned long l2ctype, set_way;
154 	int set, way;
155 
156 	__asm__("mrc p15, 1, %0, c0, c0, 1" : "=r" (l2ctype));
157 
158 	for (set = 0; set < CACHE_SET_SIZE(l2ctype); set++) {
159 		for (way = 0; way < CACHE_WAY_PER_SET; way++) {
160 			set_way = (way << 29) | (set << 5);
161 			__asm__("mcr p15, 1, %0, c7, c15, 2" : : "r"(set_way));
162 		}
163 	}
164 
165 	dsb();
166 }
167 
168 static void xsc3_l2_flush_range(unsigned long start, unsigned long end)
169 {
170 	unsigned long vaddr;
171 
172 	if (start == 0 && end == -1ul) {
173 		xsc3_l2_flush_all();
174 		return;
175 	}
176 
177 	vaddr = -1;  /* to force the first mapping */
178 
179 	start &= ~(CACHE_LINE_SIZE - 1);
180 	while (start < end) {
181 		vaddr = l2_map_va(start, vaddr);
182 		xsc3_l2_clean_mva(vaddr);
183 		xsc3_l2_inv_mva(vaddr);
184 		start += CACHE_LINE_SIZE;
185 	}
186 
187 	l2_unmap_va(vaddr);
188 
189 	dsb();
190 }
191 
192 static int __init xsc3_l2_init(void)
193 {
194 	if (!cpu_is_xsc3() || !xsc3_l2_present())
195 		return 0;
196 
197 	if (get_cr() & CR_L2) {
198 		pr_info("XScale3 L2 cache enabled.\n");
199 		xsc3_l2_inv_all();
200 
201 		outer_cache.inv_range = xsc3_l2_inv_range;
202 		outer_cache.clean_range = xsc3_l2_clean_range;
203 		outer_cache.flush_range = xsc3_l2_flush_range;
204 	}
205 
206 	return 0;
207 }
208 core_initcall(xsc3_l2_init);
209