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 phys_addr_t reg_start, reg_end;
98 bool first = true;
99 u64 i;
100
101 for_each_mem_range(i, ®_start, ®_end) {
102 if (first) {
103 phys_addr_t phys_offset = PHYS_OFFSET;
104
105 /*
106 * Initially only use memory continuous from
107 * PHYS_OFFSET */
108 if (reg_start != phys_offset)
109 panic("First memory bank must be contiguous from PHYS_OFFSET");
110 mem_end = reg_end;
111 first = false;
112 } else {
113 /*
114 * memblock auto merges contiguous blocks, remove
115 * all blocks afterwards in one go (we can't remove
116 * blocks separately while iterating)
117 */
118 pr_notice("Ignoring RAM after %pa, memory at %pa ignored\n",
119 &mem_end, ®_start);
120 memblock_remove(reg_start, 0 - reg_start);
121 break;
122 }
123 }
124 }
125
__mpu_max_regions(void)126 static int __init __mpu_max_regions(void)
127 {
128 static int max_regions;
129 u32 mpuir;
130
131 if (max_regions)
132 return max_regions;
133
134 mpuir = read_cpuid_mputype();
135
136 max_regions = (mpuir & MPUIR_DREGION_SZMASK) >> MPUIR_DREGION;
137
138 return max_regions;
139 }
140
__pmsav8_setup_region(unsigned int number,u32 bar,u32 lar)141 static int __init __pmsav8_setup_region(unsigned int number, u32 bar, u32 lar)
142 {
143 if (number > mpu_max_regions
144 || number >= MPU_MAX_REGIONS)
145 return -ENOENT;
146
147 dsb();
148 prsel_write(number);
149 isb();
150 prbar_write(bar);
151 prlar_write(lar);
152
153 mpu_rgn_info.rgns[number].prbar = bar;
154 mpu_rgn_info.rgns[number].prlar = lar;
155
156 mpu_rgn_info.used++;
157
158 return 0;
159 }
160
pmsav8_setup_ram(unsigned int number,phys_addr_t start,phys_addr_t end)161 static int __init pmsav8_setup_ram(unsigned int number, phys_addr_t start,phys_addr_t end)
162 {
163 u32 bar, lar;
164
165 if (is_region_fixed(number))
166 return -EINVAL;
167
168 bar = start;
169 lar = (end - 1) & ~(PMSAv8_MINALIGN - 1);
170
171 bar |= PMSAv8_AP_PL1RW_PL0RW | PMSAv8_RGN_SHARED;
172 lar |= PMSAv8_LAR_IDX(PMSAv8_RGN_NORMAL) | PMSAv8_LAR_EN;
173
174 return __pmsav8_setup_region(number, bar, lar);
175 }
176
pmsav8_setup_io(unsigned int number,phys_addr_t start,phys_addr_t end)177 static int __init pmsav8_setup_io(unsigned int number, phys_addr_t start,phys_addr_t end)
178 {
179 u32 bar, lar;
180
181 if (is_region_fixed(number))
182 return -EINVAL;
183
184 bar = start;
185 lar = (end - 1) & ~(PMSAv8_MINALIGN - 1);
186
187 bar |= PMSAv8_AP_PL1RW_PL0RW | PMSAv8_RGN_SHARED | PMSAv8_BAR_XN;
188 lar |= PMSAv8_LAR_IDX(PMSAv8_RGN_DEVICE_nGnRnE) | PMSAv8_LAR_EN;
189
190 return __pmsav8_setup_region(number, bar, lar);
191 }
192
pmsav8_setup_fixed(unsigned int number,phys_addr_t start,phys_addr_t end)193 static int __init pmsav8_setup_fixed(unsigned int number, phys_addr_t start,phys_addr_t end)
194 {
195 u32 bar, lar;
196
197 if (!is_region_fixed(number))
198 return -EINVAL;
199
200 bar = start;
201 lar = (end - 1) & ~(PMSAv8_MINALIGN - 1);
202
203 bar |= PMSAv8_AP_PL1RW_PL0NA | PMSAv8_RGN_SHARED;
204 lar |= PMSAv8_LAR_IDX(PMSAv8_RGN_NORMAL) | PMSAv8_LAR_EN;
205
206 prsel_write(number);
207 isb();
208
209 if (prbar_read() != bar || prlar_read() != lar)
210 return -EINVAL;
211
212 /* Reserved region was set up early, we just need a record for secondaries */
213 mpu_rgn_info.rgns[number].prbar = bar;
214 mpu_rgn_info.rgns[number].prlar = lar;
215
216 mpu_rgn_info.used++;
217
218 return 0;
219 }
220
221 #ifndef CONFIG_CPU_V7M
pmsav8_setup_vector(unsigned int number,phys_addr_t start,phys_addr_t end)222 static int __init pmsav8_setup_vector(unsigned int number, phys_addr_t start,phys_addr_t end)
223 {
224 u32 bar, lar;
225
226 if (number == PMSAv8_KERNEL_REGION)
227 return -EINVAL;
228
229 bar = start;
230 lar = (end - 1) & ~(PMSAv8_MINALIGN - 1);
231
232 bar |= PMSAv8_AP_PL1RW_PL0NA | PMSAv8_RGN_SHARED;
233 lar |= PMSAv8_LAR_IDX(PMSAv8_RGN_NORMAL) | PMSAv8_LAR_EN;
234
235 return __pmsav8_setup_region(number, bar, lar);
236 }
237 #endif
238
pmsav8_setup(void)239 void __init pmsav8_setup(void)
240 {
241 int i, err = 0;
242 int region = PMSAv8_KERNEL_REGION;
243
244 /* How many regions are supported ? */
245 mpu_max_regions = __mpu_max_regions();
246
247 /* RAM: single chunk of memory */
248 add_range(mem, ARRAY_SIZE(mem), 0, memblock.memory.regions[0].base,
249 memblock.memory.regions[0].base + memblock.memory.regions[0].size);
250
251 /* IO: cover full 4G range */
252 add_range(io, ARRAY_SIZE(io), 0, 0, 0xffffffff);
253
254 /* RAM and IO: exclude kernel */
255 subtract_range(mem, ARRAY_SIZE(mem), __pa(KERNEL_START), __pa(KERNEL_END));
256 subtract_range(io, ARRAY_SIZE(io), __pa(KERNEL_START), __pa(KERNEL_END));
257
258 #ifdef CONFIG_XIP_KERNEL
259 /* RAM and IO: exclude xip */
260 subtract_range(mem, ARRAY_SIZE(mem), CONFIG_XIP_PHYS_ADDR, __pa(_exiprom));
261 subtract_range(io, ARRAY_SIZE(io), CONFIG_XIP_PHYS_ADDR, __pa(_exiprom));
262 #endif
263
264 #ifndef CONFIG_CPU_V7M
265 /* RAM and IO: exclude vectors */
266 subtract_range(mem, ARRAY_SIZE(mem), vectors_base, vectors_base + 2 * PAGE_SIZE);
267 subtract_range(io, ARRAY_SIZE(io), vectors_base, vectors_base + 2 * PAGE_SIZE);
268 #endif
269 /* IO: exclude RAM */
270 for (i = 0; i < ARRAY_SIZE(mem); i++)
271 subtract_range(io, ARRAY_SIZE(io), mem[i].start, mem[i].end);
272
273 /* Now program MPU */
274
275 #ifdef CONFIG_XIP_KERNEL
276 /* ROM */
277 err |= pmsav8_setup_fixed(PMSAv8_XIP_REGION, CONFIG_XIP_PHYS_ADDR, __pa(_exiprom));
278 #endif
279 /* Kernel */
280 err |= pmsav8_setup_fixed(region++, __pa(KERNEL_START), __pa(KERNEL_END));
281
282
283 /* IO */
284 for (i = 0; i < ARRAY_SIZE(io); i++) {
285 if (!io[i].end)
286 continue;
287
288 err |= pmsav8_setup_io(region++, io[i].start, io[i].end);
289 }
290
291 /* RAM */
292 for (i = 0; i < ARRAY_SIZE(mem); i++) {
293 if (!mem[i].end)
294 continue;
295
296 err |= pmsav8_setup_ram(region++, mem[i].start, mem[i].end);
297 }
298
299 /* Vectors */
300 #ifndef CONFIG_CPU_V7M
301 err |= pmsav8_setup_vector(region++, vectors_base, vectors_base + 2 * PAGE_SIZE);
302 #endif
303 if (err)
304 pr_warn("MPU region initialization failure! %d", err);
305 else
306 pr_info("Using ARM PMSAv8 Compliant MPU. Used %d of %d regions\n",
307 mpu_rgn_info.used, mpu_max_regions);
308 }
309
