xref: /openbmc/linux/arch/arm/mm/cache-xsc3l2.c (revision b627b4ed)
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 <asm/system.h>
21 #include <asm/cputype.h>
22 #include <asm/cacheflush.h>
23 #include <asm/kmap_types.h>
24 #include <asm/fixmap.h>
25 #include <asm/pgtable.h>
26 #include <asm/tlbflush.h>
27 #include "mm.h"
28 
29 #define CR_L2	(1 << 26)
30 
31 #define CACHE_LINE_SIZE		32
32 #define CACHE_LINE_SHIFT	5
33 #define CACHE_WAY_PER_SET	8
34 
35 #define CACHE_WAY_SIZE(l2ctype)	(8192 << (((l2ctype) >> 8) & 0xf))
36 #define CACHE_SET_SIZE(l2ctype)	(CACHE_WAY_SIZE(l2ctype) >> CACHE_LINE_SHIFT)
37 
38 static inline int xsc3_l2_present(void)
39 {
40 	unsigned long l2ctype;
41 
42 	__asm__("mrc p15, 1, %0, c0, c0, 1" : "=r" (l2ctype));
43 
44 	return !!(l2ctype & 0xf8);
45 }
46 
47 static inline void xsc3_l2_clean_mva(unsigned long addr)
48 {
49 	__asm__("mcr p15, 1, %0, c7, c11, 1" : : "r" (addr));
50 }
51 
52 static inline void xsc3_l2_inv_mva(unsigned long addr)
53 {
54 	__asm__("mcr p15, 1, %0, c7, c7, 1" : : "r" (addr));
55 }
56 
57 static inline void xsc3_l2_inv_all(void)
58 {
59 	unsigned long l2ctype, set_way;
60 	int set, way;
61 
62 	__asm__("mrc p15, 1, %0, c0, c0, 1" : "=r" (l2ctype));
63 
64 	for (set = 0; set < CACHE_SET_SIZE(l2ctype); set++) {
65 		for (way = 0; way < CACHE_WAY_PER_SET; way++) {
66 			set_way = (way << 29) | (set << 5);
67 			__asm__("mcr p15, 1, %0, c7, c11, 2" : : "r"(set_way));
68 		}
69 	}
70 
71 	dsb();
72 }
73 
74 #ifdef CONFIG_HIGHMEM
75 #define l2_map_save_flags(x)		raw_local_save_flags(x)
76 #define l2_map_restore_flags(x)		raw_local_irq_restore(x)
77 #else
78 #define l2_map_save_flags(x)		((x) = 0)
79 #define l2_map_restore_flags(x)		((void)(x))
80 #endif
81 
82 static inline unsigned long l2_map_va(unsigned long pa, unsigned long prev_va,
83 				      unsigned long flags)
84 {
85 #ifdef CONFIG_HIGHMEM
86 	unsigned long va = prev_va & PAGE_MASK;
87 	unsigned long pa_offset = pa << (32 - PAGE_SHIFT);
88 	if (unlikely(pa_offset < (prev_va << (32 - PAGE_SHIFT)))) {
89 		/*
90 		 * Switching to a new page.  Because cache ops are
91 		 * using virtual addresses only, we must put a mapping
92 		 * in place for it.  We also enable interrupts for a
93 		 * short while and disable them again to protect this
94 		 * mapping.
95 		 */
96 		unsigned long idx;
97 		raw_local_irq_restore(flags);
98 		idx = KM_L2_CACHE + KM_TYPE_NR * smp_processor_id();
99 		va = __fix_to_virt(FIX_KMAP_BEGIN + idx);
100 		raw_local_irq_restore(flags | PSR_I_BIT);
101 		set_pte_ext(TOP_PTE(va), pfn_pte(pa >> PAGE_SHIFT, PAGE_KERNEL), 0);
102 		local_flush_tlb_kernel_page(va);
103 	}
104 	return va + (pa_offset >> (32 - PAGE_SHIFT));
105 #else
106 	return __phys_to_virt(pa);
107 #endif
108 }
109 
110 static void xsc3_l2_inv_range(unsigned long start, unsigned long end)
111 {
112 	unsigned long vaddr, flags;
113 
114 	if (start == 0 && end == -1ul) {
115 		xsc3_l2_inv_all();
116 		return;
117 	}
118 
119 	vaddr = -1;  /* to force the first mapping */
120 	l2_map_save_flags(flags);
121 
122 	/*
123 	 * Clean and invalidate partial first cache line.
124 	 */
125 	if (start & (CACHE_LINE_SIZE - 1)) {
126 		vaddr = l2_map_va(start & ~(CACHE_LINE_SIZE - 1), vaddr, flags);
127 		xsc3_l2_clean_mva(vaddr);
128 		xsc3_l2_inv_mva(vaddr);
129 		start = (start | (CACHE_LINE_SIZE - 1)) + 1;
130 	}
131 
132 	/*
133 	 * Invalidate all full cache lines between 'start' and 'end'.
134 	 */
135 	while (start < (end & ~(CACHE_LINE_SIZE - 1))) {
136 		vaddr = l2_map_va(start, vaddr, flags);
137 		xsc3_l2_inv_mva(vaddr);
138 		start += CACHE_LINE_SIZE;
139 	}
140 
141 	/*
142 	 * Clean and invalidate partial last cache line.
143 	 */
144 	if (start < end) {
145 		vaddr = l2_map_va(start, vaddr, flags);
146 		xsc3_l2_clean_mva(vaddr);
147 		xsc3_l2_inv_mva(vaddr);
148 	}
149 
150 	l2_map_restore_flags(flags);
151 
152 	dsb();
153 }
154 
155 static void xsc3_l2_clean_range(unsigned long start, unsigned long end)
156 {
157 	unsigned long vaddr, flags;
158 
159 	vaddr = -1;  /* to force the first mapping */
160 	l2_map_save_flags(flags);
161 
162 	start &= ~(CACHE_LINE_SIZE - 1);
163 	while (start < end) {
164 		vaddr = l2_map_va(start, vaddr, flags);
165 		xsc3_l2_clean_mva(vaddr);
166 		start += CACHE_LINE_SIZE;
167 	}
168 
169 	l2_map_restore_flags(flags);
170 
171 	dsb();
172 }
173 
174 /*
175  * optimize L2 flush all operation by set/way format
176  */
177 static inline void xsc3_l2_flush_all(void)
178 {
179 	unsigned long l2ctype, set_way;
180 	int set, way;
181 
182 	__asm__("mrc p15, 1, %0, c0, c0, 1" : "=r" (l2ctype));
183 
184 	for (set = 0; set < CACHE_SET_SIZE(l2ctype); set++) {
185 		for (way = 0; way < CACHE_WAY_PER_SET; way++) {
186 			set_way = (way << 29) | (set << 5);
187 			__asm__("mcr p15, 1, %0, c7, c15, 2" : : "r"(set_way));
188 		}
189 	}
190 
191 	dsb();
192 }
193 
194 static void xsc3_l2_flush_range(unsigned long start, unsigned long end)
195 {
196 	unsigned long vaddr, flags;
197 
198 	if (start == 0 && end == -1ul) {
199 		xsc3_l2_flush_all();
200 		return;
201 	}
202 
203 	vaddr = -1;  /* to force the first mapping */
204 	l2_map_save_flags(flags);
205 
206 	start &= ~(CACHE_LINE_SIZE - 1);
207 	while (start < end) {
208 		vaddr = l2_map_va(start, vaddr, flags);
209 		xsc3_l2_clean_mva(vaddr);
210 		xsc3_l2_inv_mva(vaddr);
211 		start += CACHE_LINE_SIZE;
212 	}
213 
214 	l2_map_restore_flags(flags);
215 
216 	dsb();
217 }
218 
219 static int __init xsc3_l2_init(void)
220 {
221 	if (!cpu_is_xsc3() || !xsc3_l2_present())
222 		return 0;
223 
224 	if (!(get_cr() & CR_L2)) {
225 		pr_info("XScale3 L2 cache enabled.\n");
226 		adjust_cr(CR_L2, CR_L2);
227 		xsc3_l2_inv_all();
228 	}
229 
230 	outer_cache.inv_range = xsc3_l2_inv_range;
231 	outer_cache.clean_range = xsc3_l2_clean_range;
232 	outer_cache.flush_range = xsc3_l2_flush_range;
233 
234 	return 0;
235 }
236 core_initcall(xsc3_l2_init);
237