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1/*
2 * arch/arm/mm/cache-tauros2.c - Tauros2 L2 cache controller support
3 *
4 * Copyright (C) 2008 Marvell Semiconductor
5 *
6 * This file is licensed under the terms of the GNU General Public
7 * License version 2. This program is licensed "as is" without any
8 * warranty of any kind, whether express or implied.
9 *
10 * References:
11 * - PJ1 CPU Core Datasheet,
12 * Document ID MV-S104837-01, Rev 0.7, January 24 2008.
13 * - PJ4 CPU Core Datasheet,
14 * Document ID MV-S105190-00, Rev 0.7, March 14 2008.
15 */
16
17#include <linux/init.h>
18#include <asm/cacheflush.h>
19#include <asm/hardware/cache-tauros2.h>
20
21
22/*
23 * When Tauros2 is used on a CPU that supports the v7 hierarchical
24 * cache operations, the cache handling code in proc-v7.S takes care
25 * of everything, including handling DMA coherency.
26 *
27 * So, we only need to register outer cache operations here if we're
28 * being used on a pre-v7 CPU, and we only need to build support for
29 * outer cache operations into the kernel image if the kernel has been
30 * configured to support a pre-v7 CPU.
31 */
32#if __LINUX_ARM_ARCH__ < 7
33/*
34 * Low-level cache maintenance operations.
35 */
36static inline void tauros2_clean_pa(unsigned long addr)
37{
38 __asm__("mcr p15, 1, %0, c7, c11, 3" : : "r" (addr));
39}
40
41static inline void tauros2_clean_inv_pa(unsigned long addr)
42{
43 __asm__("mcr p15, 1, %0, c7, c15, 3" : : "r" (addr));
44}
45
46static inline void tauros2_inv_pa(unsigned long addr)
47{
48 __asm__("mcr p15, 1, %0, c7, c7, 3" : : "r" (addr));
49}
50
51
52/*
53 * Linux primitives.
54 *
55 * Note that the end addresses passed to Linux primitives are
56 * noninclusive.
57 */
58#define CACHE_LINE_SIZE 32
59
60static void tauros2_inv_range(unsigned long start, unsigned long end)
61{
62 /*
63 * Clean and invalidate partial first cache line.
64 */
65 if (start & (CACHE_LINE_SIZE - 1)) {
66 tauros2_clean_inv_pa(start & ~(CACHE_LINE_SIZE - 1));
67 start = (start | (CACHE_LINE_SIZE - 1)) + 1;
68 }
69
70 /*
71 * Clean and invalidate partial last cache line.
72 */
73 if (end & (CACHE_LINE_SIZE - 1)) {
74 tauros2_clean_inv_pa(end & ~(CACHE_LINE_SIZE - 1));
75 end &= ~(CACHE_LINE_SIZE - 1);
76 }
77
78 /*
79 * Invalidate all full cache lines between 'start' and 'end'.
80 */
81 while (start < end) {
82 tauros2_inv_pa(start);
83 start += CACHE_LINE_SIZE;
84 }
85
86 dsb();
87}
88
89static void tauros2_clean_range(unsigned long start, unsigned long end)
90{
91 start &= ~(CACHE_LINE_SIZE - 1);
92 while (start < end) {
93 tauros2_clean_pa(start);
94 start += CACHE_LINE_SIZE;
95 }
96
97 dsb();
98}
99
100static void tauros2_flush_range(unsigned long start, unsigned long end)
101{
102 start &= ~(CACHE_LINE_SIZE - 1);
103 while (start < end) {
104 tauros2_clean_inv_pa(start);
105 start += CACHE_LINE_SIZE;
106 }
107
108 dsb();
109}
110#endif
111
112static inline u32 __init read_extra_features(void)
113{
114 u32 u;
115
116 __asm__("mrc p15, 1, %0, c15, c1, 0" : "=r" (u));
117
118 return u;
119}
120
121static inline void __init write_extra_features(u32 u)
122{
123 __asm__("mcr p15, 1, %0, c15, c1, 0" : : "r" (u));
124}
125
126static void __init disable_l2_prefetch(void)
127{
128 u32 u;
129
130 /*
131 * Read the CPU Extra Features register and verify that the
132 * Disable L2 Prefetch bit is set.
133 */
134 u = read_extra_features();
135 if (!(u & 0x01000000)) {
136 printk(KERN_INFO "Tauros2: Disabling L2 prefetch.\n");
137 write_extra_features(u | 0x01000000);
138 }
139}
140
141static inline int __init cpuid_scheme(void)
142{
143 extern int processor_id;
144
145 return !!((processor_id & 0x000f0000) == 0x000f0000);
146}
147
148static inline u32 __init read_mmfr3(void)
149{
150 u32 mmfr3;
151
152 __asm__("mrc p15, 0, %0, c0, c1, 7\n" : "=r" (mmfr3));
153
154 return mmfr3;
155}
156
157static inline u32 __init read_actlr(void)
158{
159 u32 actlr;
160
161 __asm__("mrc p15, 0, %0, c1, c0, 1\n" : "=r" (actlr));
162
163 return actlr;
164}
165
166static inline void __init write_actlr(u32 actlr)
167{
168 __asm__("mcr p15, 0, %0, c1, c0, 1\n" : : "r" (actlr));
169}
170
171void __init tauros2_init(void)
172{
173 extern int processor_id;
174 char *mode;
175
176 disable_l2_prefetch();
177
178#ifdef CONFIG_CPU_32v5
179 if ((processor_id & 0xff0f0000) == 0x56050000) {
180 u32 feat;
181
182 /*
183 * v5 CPUs with Tauros2 have the L2 cache enable bit
184 * located in the CPU Extra Features register.
185 */
186 feat = read_extra_features();
187 if (!(feat & 0x00400000)) {
188 printk(KERN_INFO "Tauros2: Enabling L2 cache.\n");
189 write_extra_features(feat | 0x00400000);
190 }
191
192 mode = "ARMv5";
193 outer_cache.inv_range = tauros2_inv_range;
194 outer_cache.clean_range = tauros2_clean_range;
195 outer_cache.flush_range = tauros2_flush_range;
196 }
197#endif
198
199#ifdef CONFIG_CPU_32v6
200 /*
201 * Check whether this CPU lacks support for the v7 hierarchical
202 * cache ops. (PJ4 is in its v6 personality mode if the MMFR3
203 * register indicates no support for the v7 hierarchical cache
204 * ops.)
205 */
206 if (cpuid_scheme() && (read_mmfr3() & 0xf) == 0) {
207 /*
208 * When Tauros2 is used in an ARMv6 system, the L2
209 * enable bit is in the ARMv6 ARM-mandated position
210 * (bit [26] of the System Control Register).
211 */
212 if (!(get_cr() & 0x04000000)) {
213 printk(KERN_INFO "Tauros2: Enabling L2 cache.\n");
214 adjust_cr(0x04000000, 0x04000000);
215 }
216
217 mode = "ARMv6";
218 outer_cache.inv_range = tauros2_inv_range;
219 outer_cache.clean_range = tauros2_clean_range;
220 outer_cache.flush_range = tauros2_flush_range;
221 }
222#endif
223
224#ifdef CONFIG_CPU_32v7
225 /*
226 * Check whether this CPU has support for the v7 hierarchical
227 * cache ops. (PJ4 is in its v7 personality mode if the MMFR3
228 * register indicates support for the v7 hierarchical cache
229 * ops.)
230 *
231 * (Although strictly speaking there may exist CPUs that
232 * implement the v7 cache ops but are only ARMv6 CPUs (due to
233 * not complying with all of the other ARMv7 requirements),
234 * there are no real-life examples of Tauros2 being used on
235 * such CPUs as of yet.)
236 */
237 if (cpuid_scheme() && (read_mmfr3() & 0xf) == 1) {
238 u32 actlr;
239
240 /*
241 * When Tauros2 is used in an ARMv7 system, the L2
242 * enable bit is located in the Auxiliary System Control
243 * Register (which is the only register allowed by the
244 * ARMv7 spec to contain fine-grained cache control bits).
245 */
246 actlr = read_actlr();
247 if (!(actlr & 0x00000002)) {
248 printk(KERN_INFO "Tauros2: Enabling L2 cache.\n");
249 write_actlr(actlr | 0x00000002);
250 }
251
252 mode = "ARMv7";
253 }
254#endif
255
256 if (mode == NULL) {
257 printk(KERN_CRIT "Tauros2: Unable to detect CPU mode.\n");
258 return;
259 }
260
261 printk(KERN_INFO "Tauros2: L2 cache support initialised "
262 "in %s mode.\n", mode);
263}
1/*
2 * arch/arm/mm/cache-tauros2.c - Tauros2 L2 cache controller support
3 *
4 * Copyright (C) 2008 Marvell Semiconductor
5 *
6 * This file is licensed under the terms of the GNU General Public
7 * License version 2. This program is licensed "as is" without any
8 * warranty of any kind, whether express or implied.
9 *
10 * References:
11 * - PJ1 CPU Core Datasheet,
12 * Document ID MV-S104837-01, Rev 0.7, January 24 2008.
13 * - PJ4 CPU Core Datasheet,
14 * Document ID MV-S105190-00, Rev 0.7, March 14 2008.
15 */
16
17#include <linux/init.h>
18#include <linux/of.h>
19#include <linux/of_address.h>
20#include <asm/cacheflush.h>
21#include <asm/cp15.h>
22#include <asm/cputype.h>
23#include <asm/hardware/cache-tauros2.h>
24
25/* CP15 PJ4 Control configuration register */
26#define CCR_L2C_PREFETCH_DISABLE BIT(24)
27#define CCR_L2C_ECC_ENABLE BIT(23)
28#define CCR_L2C_WAY7_4_DISABLE BIT(21)
29#define CCR_L2C_BURST8_ENABLE BIT(20)
30
31/*
32 * When Tauros2 is used on a CPU that supports the v7 hierarchical
33 * cache operations, the cache handling code in proc-v7.S takes care
34 * of everything, including handling DMA coherency.
35 *
36 * So, we only need to register outer cache operations here if we're
37 * being used on a pre-v7 CPU, and we only need to build support for
38 * outer cache operations into the kernel image if the kernel has been
39 * configured to support a pre-v7 CPU.
40 */
41#ifdef CONFIG_CPU_32v5
42/*
43 * Low-level cache maintenance operations.
44 */
45static inline void tauros2_clean_pa(unsigned long addr)
46{
47 __asm__("mcr p15, 1, %0, c7, c11, 3" : : "r" (addr));
48}
49
50static inline void tauros2_clean_inv_pa(unsigned long addr)
51{
52 __asm__("mcr p15, 1, %0, c7, c15, 3" : : "r" (addr));
53}
54
55static inline void tauros2_inv_pa(unsigned long addr)
56{
57 __asm__("mcr p15, 1, %0, c7, c7, 3" : : "r" (addr));
58}
59
60
61/*
62 * Linux primitives.
63 *
64 * Note that the end addresses passed to Linux primitives are
65 * noninclusive.
66 */
67#define CACHE_LINE_SIZE 32
68
69static void tauros2_inv_range(unsigned long start, unsigned long end)
70{
71 /*
72 * Clean and invalidate partial first cache line.
73 */
74 if (start & (CACHE_LINE_SIZE - 1)) {
75 tauros2_clean_inv_pa(start & ~(CACHE_LINE_SIZE - 1));
76 start = (start | (CACHE_LINE_SIZE - 1)) + 1;
77 }
78
79 /*
80 * Clean and invalidate partial last cache line.
81 */
82 if (end & (CACHE_LINE_SIZE - 1)) {
83 tauros2_clean_inv_pa(end & ~(CACHE_LINE_SIZE - 1));
84 end &= ~(CACHE_LINE_SIZE - 1);
85 }
86
87 /*
88 * Invalidate all full cache lines between 'start' and 'end'.
89 */
90 while (start < end) {
91 tauros2_inv_pa(start);
92 start += CACHE_LINE_SIZE;
93 }
94
95 dsb();
96}
97
98static void tauros2_clean_range(unsigned long start, unsigned long end)
99{
100 start &= ~(CACHE_LINE_SIZE - 1);
101 while (start < end) {
102 tauros2_clean_pa(start);
103 start += CACHE_LINE_SIZE;
104 }
105
106 dsb();
107}
108
109static void tauros2_flush_range(unsigned long start, unsigned long end)
110{
111 start &= ~(CACHE_LINE_SIZE - 1);
112 while (start < end) {
113 tauros2_clean_inv_pa(start);
114 start += CACHE_LINE_SIZE;
115 }
116
117 dsb();
118}
119
120static void tauros2_disable(void)
121{
122 __asm__ __volatile__ (
123 "mcr p15, 1, %0, c7, c11, 0 @L2 Cache Clean All\n\t"
124 "mrc p15, 0, %0, c1, c0, 0\n\t"
125 "bic %0, %0, #(1 << 26)\n\t"
126 "mcr p15, 0, %0, c1, c0, 0 @Disable L2 Cache\n\t"
127 : : "r" (0x0));
128}
129
130static void tauros2_resume(void)
131{
132 __asm__ __volatile__ (
133 "mcr p15, 1, %0, c7, c7, 0 @L2 Cache Invalidate All\n\t"
134 "mrc p15, 0, %0, c1, c0, 0\n\t"
135 "orr %0, %0, #(1 << 26)\n\t"
136 "mcr p15, 0, %0, c1, c0, 0 @Enable L2 Cache\n\t"
137 : : "r" (0x0));
138}
139#endif
140
141static inline u32 __init read_extra_features(void)
142{
143 u32 u;
144
145 __asm__("mrc p15, 1, %0, c15, c1, 0" : "=r" (u));
146
147 return u;
148}
149
150static inline void __init write_extra_features(u32 u)
151{
152 __asm__("mcr p15, 1, %0, c15, c1, 0" : : "r" (u));
153}
154
155static inline int __init cpuid_scheme(void)
156{
157 return !!((processor_id & 0x000f0000) == 0x000f0000);
158}
159
160static inline u32 __init read_mmfr3(void)
161{
162 u32 mmfr3;
163
164 __asm__("mrc p15, 0, %0, c0, c1, 7\n" : "=r" (mmfr3));
165
166 return mmfr3;
167}
168
169static inline u32 __init read_actlr(void)
170{
171 u32 actlr;
172
173 __asm__("mrc p15, 0, %0, c1, c0, 1\n" : "=r" (actlr));
174
175 return actlr;
176}
177
178static inline void __init write_actlr(u32 actlr)
179{
180 __asm__("mcr p15, 0, %0, c1, c0, 1\n" : : "r" (actlr));
181}
182
183static void enable_extra_feature(unsigned int features)
184{
185 u32 u;
186
187 u = read_extra_features();
188
189 if (features & CACHE_TAUROS2_PREFETCH_ON)
190 u &= ~CCR_L2C_PREFETCH_DISABLE;
191 else
192 u |= CCR_L2C_PREFETCH_DISABLE;
193 pr_info("Tauros2: %s L2 prefetch.\n",
194 (features & CACHE_TAUROS2_PREFETCH_ON)
195 ? "Enabling" : "Disabling");
196
197 if (features & CACHE_TAUROS2_LINEFILL_BURST8)
198 u |= CCR_L2C_BURST8_ENABLE;
199 else
200 u &= ~CCR_L2C_BURST8_ENABLE;
201 pr_info("Tauros2: %s burst8 line fill.\n",
202 (features & CACHE_TAUROS2_LINEFILL_BURST8)
203 ? "Enabling" : "Disabling");
204
205 write_extra_features(u);
206}
207
208static void __init tauros2_internal_init(unsigned int features)
209{
210 char *mode = NULL;
211
212 enable_extra_feature(features);
213
214#ifdef CONFIG_CPU_32v5
215 if ((processor_id & 0xff0f0000) == 0x56050000) {
216 u32 feat;
217
218 /*
219 * v5 CPUs with Tauros2 have the L2 cache enable bit
220 * located in the CPU Extra Features register.
221 */
222 feat = read_extra_features();
223 if (!(feat & 0x00400000)) {
224 pr_info("Tauros2: Enabling L2 cache.\n");
225 write_extra_features(feat | 0x00400000);
226 }
227
228 mode = "ARMv5";
229 outer_cache.inv_range = tauros2_inv_range;
230 outer_cache.clean_range = tauros2_clean_range;
231 outer_cache.flush_range = tauros2_flush_range;
232 outer_cache.disable = tauros2_disable;
233 outer_cache.resume = tauros2_resume;
234 }
235#endif
236
237#ifdef CONFIG_CPU_32v7
238 /*
239 * Check whether this CPU has support for the v7 hierarchical
240 * cache ops. (PJ4 is in its v7 personality mode if the MMFR3
241 * register indicates support for the v7 hierarchical cache
242 * ops.)
243 *
244 * (Although strictly speaking there may exist CPUs that
245 * implement the v7 cache ops but are only ARMv6 CPUs (due to
246 * not complying with all of the other ARMv7 requirements),
247 * there are no real-life examples of Tauros2 being used on
248 * such CPUs as of yet.)
249 */
250 if (cpuid_scheme() && (read_mmfr3() & 0xf) == 1) {
251 u32 actlr;
252
253 /*
254 * When Tauros2 is used in an ARMv7 system, the L2
255 * enable bit is located in the Auxiliary System Control
256 * Register (which is the only register allowed by the
257 * ARMv7 spec to contain fine-grained cache control bits).
258 */
259 actlr = read_actlr();
260 if (!(actlr & 0x00000002)) {
261 pr_info("Tauros2: Enabling L2 cache.\n");
262 write_actlr(actlr | 0x00000002);
263 }
264
265 mode = "ARMv7";
266 }
267#endif
268
269 if (mode == NULL) {
270 pr_crit("Tauros2: Unable to detect CPU mode.\n");
271 return;
272 }
273
274 pr_info("Tauros2: L2 cache support initialised "
275 "in %s mode.\n", mode);
276}
277
278#ifdef CONFIG_OF
279static const struct of_device_id tauros2_ids[] __initconst = {
280 { .compatible = "marvell,tauros2-cache"},
281 {}
282};
283#endif
284
285void __init tauros2_init(unsigned int features)
286{
287#ifdef CONFIG_OF
288 struct device_node *node;
289 int ret;
290 unsigned int f;
291
292 node = of_find_matching_node(NULL, tauros2_ids);
293 if (!node) {
294 pr_info("Not found marvell,tauros2-cache, disable it\n");
295 } else {
296 ret = of_property_read_u32(node, "marvell,tauros2-cache-features", &f);
297 if (ret) {
298 pr_info("Not found marvell,tauros-cache-features property, "
299 "disable extra features\n");
300 features = 0;
301 } else
302 features = f;
303 }
304#endif
305 tauros2_internal_init(features);
306}