1 /*
2 * Based on linux/arch/arm/pmsa-v7.c
3 *
4 * ARM PMSAv8 supporting functions.
5 */
6
7 #include <linux/memblock.h>
8 #include <linux/range.h>
9
10 #include <asm/cp15.h>
11 #include <asm/cputype.h>
12 #include <asm/mpu.h>
13
14 #include <asm/memory.h>
15 #include <asm/sections.h>
16
17 #include "mm.h"
18
19 #ifndef CONFIG_CPU_V7M
20
21 #define PRSEL __ACCESS_CP15(c6, 0, c2, 1)
22 #define PRBAR __ACCESS_CP15(c6, 0, c3, 0)
23 #define PRLAR __ACCESS_CP15(c6, 0, c3, 1)
24
prlar_read(void)25 static inline u32 prlar_read(void)
26 {
27 return read_sysreg(PRLAR);
28 }
29
prbar_read(void)30 static inline u32 prbar_read(void)
31 {
32 return read_sysreg(PRBAR);
33 }
34
prsel_write(u32 v)35 static inline void prsel_write(u32 v)
36 {
37 write_sysreg(v, PRSEL);
38 }
39
prbar_write(u32 v)40 static inline void prbar_write(u32 v)
41 {
42 write_sysreg(v, PRBAR);
43 }
44
prlar_write(u32 v)45 static inline void prlar_write(u32 v)
46 {
47 write_sysreg(v, PRLAR);
48 }
49 #else
50
prlar_read(void)51 static inline u32 prlar_read(void)
52 {
53 return readl_relaxed(BASEADDR_V7M_SCB + PMSAv8_RLAR);
54 }
55
prbar_read(void)56 static inline u32 prbar_read(void)
57 {
58 return readl_relaxed(BASEADDR_V7M_SCB + PMSAv8_RBAR);
59 }
60
prsel_write(u32 v)61 static inline void prsel_write(u32 v)
62 {
63 writel_relaxed(v, BASEADDR_V7M_SCB + PMSAv8_RNR);
64 }
65
prbar_write(u32 v)66 static inline void prbar_write(u32 v)
67 {
68 writel_relaxed(v, BASEADDR_V7M_SCB + PMSAv8_RBAR);
69 }
70
prlar_write(u32 v)71 static inline void prlar_write(u32 v)
72 {
73 writel_relaxed(v, BASEADDR_V7M_SCB + PMSAv8_RLAR);
74 }
75
76 #endif
77
78 static struct range __initdata io[MPU_MAX_REGIONS];
79 static struct range __initdata mem[MPU_MAX_REGIONS];
80
81 static unsigned int __initdata mpu_max_regions;
82
is_region_fixed(int number)83 static __init bool is_region_fixed(int number)
84 {
85 switch (number) {
86 case PMSAv8_XIP_REGION:
87 case PMSAv8_KERNEL_REGION:
88 return true;
89 default:
90 return false;
91 }
92 }
93
pmsav8_adjust_lowmem_bounds(void)94 void __init pmsav8_adjust_lowmem_bounds(void)
95 {
96 phys_addr_t mem_end;
97 struct memblock_region *reg;
98 bool first = true;
99
100 for_each_memblock(memory, reg) {
101 if (first) {
102 phys_addr_t phys_offset = PHYS_OFFSET;
103
104 /*
105 * Initially only use memory continuous from
106 * PHYS_OFFSET */
107 if (reg->base != phys_offset)
108 panic("First memory bank must be contiguous from PHYS_OFFSET");
109 mem_end = reg->base + reg->size;
110 first = false;
111 } else {
112 /*
113 * memblock auto merges contiguous blocks, remove
114 * all blocks afterwards in one go (we can't remove
115 * blocks separately while iterating)
116 */
117 pr_notice("Ignoring RAM after %pa, memory at %pa ignored\n",
118 &mem_end, ®->base);
119 memblock_remove(reg->base, 0 - reg->base);
120 break;
121 }
122 }
123 }
124
__mpu_max_regions(void)125 static int __init __mpu_max_regions(void)
126 {
127 static int max_regions;
128 u32 mpuir;
129
130 if (max_regions)
131 return max_regions;
132
133 mpuir = read_cpuid_mputype();
134
135 max_regions = (mpuir & MPUIR_DREGION_SZMASK) >> MPUIR_DREGION;
136
137 return max_regions;
138 }
139
__pmsav8_setup_region(unsigned int number,u32 bar,u32 lar)140 static int __init __pmsav8_setup_region(unsigned int number, u32 bar, u32 lar)
141 {
142 if (number > mpu_max_regions
143 || number >= MPU_MAX_REGIONS)
144 return -ENOENT;
145
146 dsb();
147 prsel_write(number);
148 isb();
149 prbar_write(bar);
150 prlar_write(lar);
151
152 mpu_rgn_info.rgns[number].prbar = bar;
153 mpu_rgn_info.rgns[number].prlar = lar;
154
155 mpu_rgn_info.used++;
156
157 return 0;
158 }
159
pmsav8_setup_ram(unsigned int number,phys_addr_t start,phys_addr_t end)160 static int __init pmsav8_setup_ram(unsigned int number, phys_addr_t start,phys_addr_t end)
161 {
162 u32 bar, lar;
163
164 if (is_region_fixed(number))
165 return -EINVAL;
166
167 bar = start;
168 lar = (end - 1) & ~(PMSAv8_MINALIGN - 1);;
169
170 bar |= PMSAv8_AP_PL1RW_PL0RW | PMSAv8_RGN_SHARED;
171 lar |= PMSAv8_LAR_IDX(PMSAv8_RGN_NORMAL) | PMSAv8_LAR_EN;
172
173 return __pmsav8_setup_region(number, bar, lar);
174 }
175
pmsav8_setup_io(unsigned int number,phys_addr_t start,phys_addr_t end)176 static int __init pmsav8_setup_io(unsigned int number, phys_addr_t start,phys_addr_t end)
177 {
178 u32 bar, lar;
179
180 if (is_region_fixed(number))
181 return -EINVAL;
182
183 bar = start;
184 lar = (end - 1) & ~(PMSAv8_MINALIGN - 1);;
185
186 bar |= PMSAv8_AP_PL1RW_PL0RW | PMSAv8_RGN_SHARED | PMSAv8_BAR_XN;
187 lar |= PMSAv8_LAR_IDX(PMSAv8_RGN_DEVICE_nGnRnE) | PMSAv8_LAR_EN;
188
189 return __pmsav8_setup_region(number, bar, lar);
190 }
191
pmsav8_setup_fixed(unsigned int number,phys_addr_t start,phys_addr_t end)192 static int __init pmsav8_setup_fixed(unsigned int number, phys_addr_t start,phys_addr_t end)
193 {
194 u32 bar, lar;
195
196 if (!is_region_fixed(number))
197 return -EINVAL;
198
199 bar = start;
200 lar = (end - 1) & ~(PMSAv8_MINALIGN - 1);
201
202 bar |= PMSAv8_AP_PL1RW_PL0NA | PMSAv8_RGN_SHARED;
203 lar |= PMSAv8_LAR_IDX(PMSAv8_RGN_NORMAL) | PMSAv8_LAR_EN;
204
205 prsel_write(number);
206 isb();
207
208 if (prbar_read() != bar || prlar_read() != lar)
209 return -EINVAL;
210
211 /* Reserved region was set up early, we just need a record for secondaries */
212 mpu_rgn_info.rgns[number].prbar = bar;
213 mpu_rgn_info.rgns[number].prlar = lar;
214
215 mpu_rgn_info.used++;
216
217 return 0;
218 }
219
220 #ifndef CONFIG_CPU_V7M
pmsav8_setup_vector(unsigned int number,phys_addr_t start,phys_addr_t end)221 static int __init pmsav8_setup_vector(unsigned int number, phys_addr_t start,phys_addr_t end)
222 {
223 u32 bar, lar;
224
225 if (number == PMSAv8_KERNEL_REGION)
226 return -EINVAL;
227
228 bar = start;
229 lar = (end - 1) & ~(PMSAv8_MINALIGN - 1);
230
231 bar |= PMSAv8_AP_PL1RW_PL0NA | PMSAv8_RGN_SHARED;
232 lar |= PMSAv8_LAR_IDX(PMSAv8_RGN_NORMAL) | PMSAv8_LAR_EN;
233
234 return __pmsav8_setup_region(number, bar, lar);
235 }
236 #endif
237
pmsav8_setup(void)238 void __init pmsav8_setup(void)
239 {
240 int i, err = 0;
241 int region = PMSAv8_KERNEL_REGION;
242
243 /* How many regions are supported ? */
244 mpu_max_regions = __mpu_max_regions();
245
246 /* RAM: single chunk of memory */
247 add_range(mem, ARRAY_SIZE(mem), 0, memblock.memory.regions[0].base,
248 memblock.memory.regions[0].base + memblock.memory.regions[0].size);
249
250 /* IO: cover full 4G range */
251 add_range(io, ARRAY_SIZE(io), 0, 0, 0xffffffff);
252
253 /* RAM and IO: exclude kernel */
254 subtract_range(mem, ARRAY_SIZE(mem), __pa(KERNEL_START), __pa(KERNEL_END));
255 subtract_range(io, ARRAY_SIZE(io), __pa(KERNEL_START), __pa(KERNEL_END));
256
257 #ifdef CONFIG_XIP_KERNEL
258 /* RAM and IO: exclude xip */
259 subtract_range(mem, ARRAY_SIZE(mem), CONFIG_XIP_PHYS_ADDR, __pa(_exiprom));
260 subtract_range(io, ARRAY_SIZE(io), CONFIG_XIP_PHYS_ADDR, __pa(_exiprom));
261 #endif
262
263 #ifndef CONFIG_CPU_V7M
264 /* RAM and IO: exclude vectors */
265 subtract_range(mem, ARRAY_SIZE(mem), vectors_base, vectors_base + 2 * PAGE_SIZE);
266 subtract_range(io, ARRAY_SIZE(io), vectors_base, vectors_base + 2 * PAGE_SIZE);
267 #endif
268 /* IO: exclude RAM */
269 for (i = 0; i < ARRAY_SIZE(mem); i++)
270 subtract_range(io, ARRAY_SIZE(io), mem[i].start, mem[i].end);
271
272 /* Now program MPU */
273
274 #ifdef CONFIG_XIP_KERNEL
275 /* ROM */
276 err |= pmsav8_setup_fixed(PMSAv8_XIP_REGION, CONFIG_XIP_PHYS_ADDR, __pa(_exiprom));
277 #endif
278 /* Kernel */
279 err |= pmsav8_setup_fixed(region++, __pa(KERNEL_START), __pa(KERNEL_END));
280
281
282 /* IO */
283 for (i = 0; i < ARRAY_SIZE(io); i++) {
284 if (!io[i].end)
285 continue;
286
287 err |= pmsav8_setup_io(region++, io[i].start, io[i].end);
288 }
289
290 /* RAM */
291 for (i = 0; i < ARRAY_SIZE(mem); i++) {
292 if (!mem[i].end)
293 continue;
294
295 err |= pmsav8_setup_ram(region++, mem[i].start, mem[i].end);
296 }
297
298 /* Vectors */
299 #ifndef CONFIG_CPU_V7M
300 err |= pmsav8_setup_vector(region++, vectors_base, vectors_base + 2 * PAGE_SIZE);
301 #endif
302 if (err)
303 pr_warn("MPU region initialization failure! %d", err);
304 else
305 pr_info("Using ARM PMSAv8 Compliant MPU. Used %d of %d regions\n",
306 mpu_rgn_info.used, mpu_max_regions);
307 }
308