1 #ifndef __ASM_ARM_SYSTEM_H
2 #define __ASM_ARM_SYSTEM_H
3
4 #include <common.h>
5 #include <linux/compiler.h>
6 #include <asm/barriers.h>
7
8 #ifdef CONFIG_ARM64
9
10 /*
11 * SCTLR_EL1/SCTLR_EL2/SCTLR_EL3 bits definitions
12 */
13 #define CR_M (1 << 0) /* MMU enable */
14 #define CR_A (1 << 1) /* Alignment abort enable */
15 #define CR_C (1 << 2) /* Dcache enable */
16 #define CR_SA (1 << 3) /* Stack Alignment Check Enable */
17 #define CR_I (1 << 12) /* Icache enable */
18 #define CR_WXN (1 << 19) /* Write Permision Imply XN */
19 #define CR_EE (1 << 25) /* Exception (Big) Endian */
20
21 #define ES_TO_AARCH64 1
22 #define ES_TO_AARCH32 0
23
24 /*
25 * SCR_EL3 bits definitions
26 */
27 #define SCR_EL3_RW_AARCH64 (1 << 10) /* Next lower level is AArch64 */
28 #define SCR_EL3_RW_AARCH32 (0 << 10) /* Lower lowers level are AArch32 */
29 #define SCR_EL3_HCE_EN (1 << 8) /* Hypervisor Call enable */
30 #define SCR_EL3_SMD_DIS (1 << 7) /* Secure Monitor Call disable */
31 #define SCR_EL3_RES1 (3 << 4) /* Reserved, RES1 */
32 #define SCR_EL3_EA_EN (1 << 3) /* External aborts taken to EL3 */
33 #define SCR_EL3_NS_EN (1 << 0) /* EL0 and EL1 in Non-scure state */
34
35 /*
36 * SPSR_EL3/SPSR_EL2 bits definitions
37 */
38 #define SPSR_EL_END_LE (0 << 9) /* Exception Little-endian */
39 #define SPSR_EL_DEBUG_MASK (1 << 9) /* Debug exception masked */
40 #define SPSR_EL_ASYN_MASK (1 << 8) /* Asynchronous data abort masked */
41 #define SPSR_EL_SERR_MASK (1 << 8) /* System Error exception masked */
42 #define SPSR_EL_IRQ_MASK (1 << 7) /* IRQ exception masked */
43 #define SPSR_EL_FIQ_MASK (1 << 6) /* FIQ exception masked */
44 #define SPSR_EL_T_A32 (0 << 5) /* AArch32 instruction set A32 */
45 #define SPSR_EL_M_AARCH64 (0 << 4) /* Exception taken from AArch64 */
46 #define SPSR_EL_M_AARCH32 (1 << 4) /* Exception taken from AArch32 */
47 #define SPSR_EL_M_SVC (0x3) /* Exception taken from SVC mode */
48 #define SPSR_EL_M_HYP (0xa) /* Exception taken from HYP mode */
49 #define SPSR_EL_M_EL1H (5) /* Exception taken from EL1h mode */
50 #define SPSR_EL_M_EL2H (9) /* Exception taken from EL2h mode */
51
52 /*
53 * CPTR_EL2 bits definitions
54 */
55 #define CPTR_EL2_RES1 (3 << 12 | 0x3ff) /* Reserved, RES1 */
56
57 /*
58 * SCTLR_EL2 bits definitions
59 */
60 #define SCTLR_EL2_RES1 (3 << 28 | 3 << 22 | 1 << 18 | 1 << 16 |\
61 1 << 11 | 3 << 4) /* Reserved, RES1 */
62 #define SCTLR_EL2_EE_LE (0 << 25) /* Exception Little-endian */
63 #define SCTLR_EL2_WXN_DIS (0 << 19) /* Write permission is not XN */
64 #define SCTLR_EL2_ICACHE_DIS (0 << 12) /* Instruction cache disabled */
65 #define SCTLR_EL2_SA_DIS (0 << 3) /* Stack Alignment Check disabled */
66 #define SCTLR_EL2_DCACHE_DIS (0 << 2) /* Data cache disabled */
67 #define SCTLR_EL2_ALIGN_DIS (0 << 1) /* Alignment check disabled */
68 #define SCTLR_EL2_MMU_DIS (0) /* MMU disabled */
69
70 /*
71 * CNTHCTL_EL2 bits definitions
72 */
73 #define CNTHCTL_EL2_EL1PCEN_EN (1 << 1) /* Physical timer regs accessible */
74 #define CNTHCTL_EL2_EL1PCTEN_EN (1 << 0) /* Physical counter accessible */
75
76 /*
77 * HCR_EL2 bits definitions
78 */
79 #define HCR_EL2_RW_AARCH64 (1 << 31) /* EL1 is AArch64 */
80 #define HCR_EL2_RW_AARCH32 (0 << 31) /* Lower levels are AArch32 */
81 #define HCR_EL2_HCD_DIS (1 << 29) /* Hypervisor Call disabled */
82
83 /*
84 * CPACR_EL1 bits definitions
85 */
86 #define CPACR_EL1_FPEN_EN (3 << 20) /* SIMD and FP instruction enabled */
87
88 /*
89 * SCTLR_EL1 bits definitions
90 */
91 #define SCTLR_EL1_RES1 (3 << 28 | 3 << 22 | 1 << 20 |\
92 1 << 11) /* Reserved, RES1 */
93 #define SCTLR_EL1_UCI_DIS (0 << 26) /* Cache instruction disabled */
94 #define SCTLR_EL1_EE_LE (0 << 25) /* Exception Little-endian */
95 #define SCTLR_EL1_WXN_DIS (0 << 19) /* Write permission is not XN */
96 #define SCTLR_EL1_NTWE_DIS (0 << 18) /* WFE instruction disabled */
97 #define SCTLR_EL1_NTWI_DIS (0 << 16) /* WFI instruction disabled */
98 #define SCTLR_EL1_UCT_DIS (0 << 15) /* CTR_EL0 access disabled */
99 #define SCTLR_EL1_DZE_DIS (0 << 14) /* DC ZVA instruction disabled */
100 #define SCTLR_EL1_ICACHE_DIS (0 << 12) /* Instruction cache disabled */
101 #define SCTLR_EL1_UMA_DIS (0 << 9) /* User Mask Access disabled */
102 #define SCTLR_EL1_SED_EN (0 << 8) /* SETEND instruction enabled */
103 #define SCTLR_EL1_ITD_EN (0 << 7) /* IT instruction enabled */
104 #define SCTLR_EL1_CP15BEN_DIS (0 << 5) /* CP15 barrier operation disabled */
105 #define SCTLR_EL1_SA0_DIS (0 << 4) /* Stack Alignment EL0 disabled */
106 #define SCTLR_EL1_SA_DIS (0 << 3) /* Stack Alignment EL1 disabled */
107 #define SCTLR_EL1_DCACHE_DIS (0 << 2) /* Data cache disabled */
108 #define SCTLR_EL1_ALIGN_DIS (0 << 1) /* Alignment check disabled */
109 #define SCTLR_EL1_MMU_DIS (0) /* MMU disabled */
110
111 #ifndef __ASSEMBLY__
112
113 u64 get_page_table_size(void);
114 #define PGTABLE_SIZE get_page_table_size()
115
116 /* 2MB granularity */
117 #define MMU_SECTION_SHIFT 21
118 #define MMU_SECTION_SIZE (1 << MMU_SECTION_SHIFT)
119
120 /* These constants need to be synced to the MT_ types in asm/armv8/mmu.h */
121 enum dcache_option {
122 DCACHE_OFF = 0 << 2,
123 DCACHE_WRITETHROUGH = 3 << 2,
124 DCACHE_WRITEBACK = 4 << 2,
125 DCACHE_WRITEALLOC = 4 << 2,
126 };
127
128 #define wfi() \
129 ({asm volatile( \
130 "wfi" : : : "memory"); \
131 })
132
current_el(void)133 static inline unsigned int current_el(void)
134 {
135 unsigned int el;
136 asm volatile("mrs %0, CurrentEL" : "=r" (el) : : "cc");
137 return el >> 2;
138 }
139
get_sctlr(void)140 static inline unsigned int get_sctlr(void)
141 {
142 unsigned int el, val;
143
144 el = current_el();
145 if (el == 1)
146 asm volatile("mrs %0, sctlr_el1" : "=r" (val) : : "cc");
147 else if (el == 2)
148 asm volatile("mrs %0, sctlr_el2" : "=r" (val) : : "cc");
149 else
150 asm volatile("mrs %0, sctlr_el3" : "=r" (val) : : "cc");
151
152 return val;
153 }
154
set_sctlr(unsigned int val)155 static inline void set_sctlr(unsigned int val)
156 {
157 unsigned int el;
158
159 el = current_el();
160 if (el == 1)
161 asm volatile("msr sctlr_el1, %0" : : "r" (val) : "cc");
162 else if (el == 2)
163 asm volatile("msr sctlr_el2, %0" : : "r" (val) : "cc");
164 else
165 asm volatile("msr sctlr_el3, %0" : : "r" (val) : "cc");
166
167 asm volatile("isb");
168 }
169
read_mpidr(void)170 static inline unsigned long read_mpidr(void)
171 {
172 unsigned long val;
173
174 asm volatile("mrs %0, mpidr_el1" : "=r" (val));
175
176 return val;
177 }
178
179 #define BSP_COREID 0
180
181 void __asm_flush_dcache_all(void);
182 void __asm_invalidate_dcache_all(void);
183 void __asm_flush_dcache_range(u64 start, u64 end);
184
185 /**
186 * __asm_invalidate_dcache_range() - Invalidate a range of virtual addresses
187 *
188 * This performance an invalidate from @start to @end - 1. Both addresses
189 * should be cache-aligned, otherwise this function will align the start
190 * address and may continue past the end address.
191 *
192 * Data in the address range is evicted from the cache and is not written back
193 * to memory.
194 *
195 * @start: Start address to invalidate
196 * @end: End address to invalidate up to (exclusive)
197 */
198 void __asm_invalidate_dcache_range(u64 start, u64 end);
199 void __asm_invalidate_tlb_all(void);
200 void __asm_invalidate_icache_all(void);
201 int __asm_invalidate_l3_dcache(void);
202 int __asm_flush_l3_dcache(void);
203 int __asm_invalidate_l3_icache(void);
204 void __asm_switch_ttbr(u64 new_ttbr);
205
206 /*
207 * Switch from EL3 to EL2 for ARMv8
208 *
209 * @args: For loading 64-bit OS, fdt address.
210 * For loading 32-bit OS, zero.
211 * @mach_nr: For loading 64-bit OS, zero.
212 * For loading 32-bit OS, machine nr
213 * @fdt_addr: For loading 64-bit OS, zero.
214 * For loading 32-bit OS, fdt address.
215 * @arg4: Input argument.
216 * @entry_point: kernel entry point
217 * @es_flag: execution state flag, ES_TO_AARCH64 or ES_TO_AARCH32
218 */
219 void __noreturn armv8_switch_to_el2(u64 args, u64 mach_nr, u64 fdt_addr,
220 u64 arg4, u64 entry_point, u64 es_flag);
221 /*
222 * Switch from EL2 to EL1 for ARMv8
223 *
224 * @args: For loading 64-bit OS, fdt address.
225 * For loading 32-bit OS, zero.
226 * @mach_nr: For loading 64-bit OS, zero.
227 * For loading 32-bit OS, machine nr
228 * @fdt_addr: For loading 64-bit OS, zero.
229 * For loading 32-bit OS, fdt address.
230 * @arg4: Input argument.
231 * @entry_point: kernel entry point
232 * @es_flag: execution state flag, ES_TO_AARCH64 or ES_TO_AARCH32
233 */
234 void armv8_switch_to_el1(u64 args, u64 mach_nr, u64 fdt_addr,
235 u64 arg4, u64 entry_point, u64 es_flag);
236 void armv8_el2_to_aarch32(u64 args, u64 mach_nr, u64 fdt_addr,
237 u64 arg4, u64 entry_point);
238 void gic_init(void);
239 void gic_send_sgi(unsigned long sgino);
240 void wait_for_wakeup(void);
241 void protect_secure_region(void);
242 void smp_kick_all_cpus(void);
243
244 void flush_l3_cache(void);
245 void mmu_change_region_attr(phys_addr_t start, size_t size, u64 attrs);
246
247 /*
248 *Issue a secure monitor call in accordance with ARM "SMC Calling convention",
249 * DEN0028A
250 *
251 * @args: input and output arguments
252 *
253 */
254 void smc_call(struct pt_regs *args);
255
256 void __noreturn psci_system_reset(void);
257 void __noreturn psci_system_off(void);
258
259 #ifdef CONFIG_ARMV8_PSCI
260 extern char __secure_start[];
261 extern char __secure_end[];
262 extern char __secure_stack_start[];
263 extern char __secure_stack_end[];
264
265 void armv8_setup_psci(void);
266 void psci_setup_vectors(void);
267 void psci_arch_init(void);
268 #endif
269
270 #endif /* __ASSEMBLY__ */
271
272 #else /* CONFIG_ARM64 */
273
274 #ifdef __KERNEL__
275
276 #define CPU_ARCH_UNKNOWN 0
277 #define CPU_ARCH_ARMv3 1
278 #define CPU_ARCH_ARMv4 2
279 #define CPU_ARCH_ARMv4T 3
280 #define CPU_ARCH_ARMv5 4
281 #define CPU_ARCH_ARMv5T 5
282 #define CPU_ARCH_ARMv5TE 6
283 #define CPU_ARCH_ARMv5TEJ 7
284 #define CPU_ARCH_ARMv6 8
285 #define CPU_ARCH_ARMv7 9
286
287 /*
288 * CR1 bits (CP#15 CR1)
289 */
290 #define CR_M (1 << 0) /* MMU enable */
291 #define CR_A (1 << 1) /* Alignment abort enable */
292 #define CR_C (1 << 2) /* Dcache enable */
293 #define CR_W (1 << 3) /* Write buffer enable */
294 #define CR_P (1 << 4) /* 32-bit exception handler */
295 #define CR_D (1 << 5) /* 32-bit data address range */
296 #define CR_L (1 << 6) /* Implementation defined */
297 #define CR_B (1 << 7) /* Big endian */
298 #define CR_S (1 << 8) /* System MMU protection */
299 #define CR_R (1 << 9) /* ROM MMU protection */
300 #define CR_F (1 << 10) /* Implementation defined */
301 #define CR_Z (1 << 11) /* Implementation defined */
302 #define CR_I (1 << 12) /* Icache enable */
303 #define CR_V (1 << 13) /* Vectors relocated to 0xffff0000 */
304 #define CR_RR (1 << 14) /* Round Robin cache replacement */
305 #define CR_L4 (1 << 15) /* LDR pc can set T bit */
306 #define CR_DT (1 << 16)
307 #define CR_IT (1 << 18)
308 #define CR_ST (1 << 19)
309 #define CR_FI (1 << 21) /* Fast interrupt (lower latency mode) */
310 #define CR_U (1 << 22) /* Unaligned access operation */
311 #define CR_XP (1 << 23) /* Extended page tables */
312 #define CR_VE (1 << 24) /* Vectored interrupts */
313 #define CR_EE (1 << 25) /* Exception (Big) Endian */
314 #define CR_TRE (1 << 28) /* TEX remap enable */
315 #define CR_AFE (1 << 29) /* Access flag enable */
316 #define CR_TE (1 << 30) /* Thumb exception enable */
317
318 #if defined(CONFIG_ARMV7_LPAE) && !defined(PGTABLE_SIZE)
319 #define PGTABLE_SIZE (4096 * 5)
320 #elif !defined(PGTABLE_SIZE)
321 #define PGTABLE_SIZE (4096 * 4)
322 #endif
323
324 /*
325 * This is used to ensure the compiler did actually allocate the register we
326 * asked it for some inline assembly sequences. Apparently we can't trust
327 * the compiler from one version to another so a bit of paranoia won't hurt.
328 * This string is meant to be concatenated with the inline asm string and
329 * will cause compilation to stop on mismatch.
330 * (for details, see gcc PR 15089)
331 */
332 #define __asmeq(x, y) ".ifnc " x "," y " ; .err ; .endif\n\t"
333
334 #ifndef __ASSEMBLY__
335
336 #ifdef CONFIG_ARMV7_LPAE
337 void switch_to_hypervisor_ret(void);
338 #endif
339
340 #define nop() __asm__ __volatile__("mov\tr0,r0\t@ nop\n\t");
341
342 #ifdef __ARM_ARCH_7A__
343 #define wfi() __asm__ __volatile__ ("wfi" : : : "memory")
344 #else
345 #define wfi()
346 #endif
347
get_cpsr(void)348 static inline unsigned long get_cpsr(void)
349 {
350 unsigned long cpsr;
351
352 asm volatile("mrs %0, cpsr" : "=r"(cpsr): );
353 return cpsr;
354 }
355
is_hyp(void)356 static inline int is_hyp(void)
357 {
358 #ifdef CONFIG_ARMV7_LPAE
359 /* HYP mode requires LPAE ... */
360 return ((get_cpsr() & 0x1f) == 0x1a);
361 #else
362 /* ... so without LPAE support we can optimize all hyp code away */
363 return 0;
364 #endif
365 }
366
get_cr(void)367 static inline unsigned int get_cr(void)
368 {
369 unsigned int val;
370
371 if (is_hyp())
372 asm volatile("mrc p15, 4, %0, c1, c0, 0 @ get CR" : "=r" (val)
373 :
374 : "cc");
375 else
376 asm volatile("mrc p15, 0, %0, c1, c0, 0 @ get CR" : "=r" (val)
377 :
378 : "cc");
379 return val;
380 }
381
set_cr(unsigned int val)382 static inline void set_cr(unsigned int val)
383 {
384 if (is_hyp())
385 asm volatile("mcr p15, 4, %0, c1, c0, 0 @ set CR" :
386 : "r" (val)
387 : "cc");
388 else
389 asm volatile("mcr p15, 0, %0, c1, c0, 0 @ set CR" :
390 : "r" (val)
391 : "cc");
392 isb();
393 }
394
get_dacr(void)395 static inline unsigned int get_dacr(void)
396 {
397 unsigned int val;
398 asm("mrc p15, 0, %0, c3, c0, 0 @ get DACR" : "=r" (val) : : "cc");
399 return val;
400 }
401
set_dacr(unsigned int val)402 static inline void set_dacr(unsigned int val)
403 {
404 asm volatile("mcr p15, 0, %0, c3, c0, 0 @ set DACR"
405 : : "r" (val) : "cc");
406 isb();
407 }
408
409 #ifdef CONFIG_ARMV7_LPAE
410 /* Long-Descriptor Translation Table Level 1/2 Bits */
411 #define TTB_SECT_XN_MASK (1ULL << 54)
412 #define TTB_SECT_NG_MASK (1 << 11)
413 #define TTB_SECT_AF (1 << 10)
414 #define TTB_SECT_SH_MASK (3 << 8)
415 #define TTB_SECT_NS_MASK (1 << 5)
416 #define TTB_SECT_AP (1 << 6)
417 /* Note: TTB AP bits are set elsewhere */
418 #define TTB_SECT_MAIR(x) ((x & 0x7) << 2) /* Index into MAIR */
419 #define TTB_SECT (1 << 0)
420 #define TTB_PAGETABLE (3 << 0)
421
422 /* TTBCR flags */
423 #define TTBCR_EAE (1 << 31)
424 #define TTBCR_T0SZ(x) ((x) << 0)
425 #define TTBCR_T1SZ(x) ((x) << 16)
426 #define TTBCR_USING_TTBR0 (TTBCR_T0SZ(0) | TTBCR_T1SZ(0))
427 #define TTBCR_IRGN0_NC (0 << 8)
428 #define TTBCR_IRGN0_WBWA (1 << 8)
429 #define TTBCR_IRGN0_WT (2 << 8)
430 #define TTBCR_IRGN0_WBNWA (3 << 8)
431 #define TTBCR_IRGN0_MASK (3 << 8)
432 #define TTBCR_ORGN0_NC (0 << 10)
433 #define TTBCR_ORGN0_WBWA (1 << 10)
434 #define TTBCR_ORGN0_WT (2 << 10)
435 #define TTBCR_ORGN0_WBNWA (3 << 10)
436 #define TTBCR_ORGN0_MASK (3 << 10)
437 #define TTBCR_SHARED_NON (0 << 12)
438 #define TTBCR_SHARED_OUTER (2 << 12)
439 #define TTBCR_SHARED_INNER (3 << 12)
440 #define TTBCR_EPD0 (0 << 7)
441
442 /*
443 * Memory types
444 */
445 #define MEMORY_ATTRIBUTES ((0x00 << (0 * 8)) | (0x88 << (1 * 8)) | \
446 (0xcc << (2 * 8)) | (0xff << (3 * 8)))
447
448 /* options available for data cache on each page */
449 enum dcache_option {
450 DCACHE_OFF = TTB_SECT | TTB_SECT_MAIR(0) | TTB_SECT_XN_MASK,
451 DCACHE_WRITETHROUGH = TTB_SECT | TTB_SECT_MAIR(1),
452 DCACHE_WRITEBACK = TTB_SECT | TTB_SECT_MAIR(2),
453 DCACHE_WRITEALLOC = TTB_SECT | TTB_SECT_MAIR(3),
454 };
455 #elif defined(CONFIG_CPU_V7A)
456 /* Short-Descriptor Translation Table Level 1 Bits */
457 #define TTB_SECT_NS_MASK (1 << 19)
458 #define TTB_SECT_NG_MASK (1 << 17)
459 #define TTB_SECT_S_MASK (1 << 16)
460 /* Note: TTB AP bits are set elsewhere */
461 #define TTB_SECT_AP (3 << 10)
462 #define TTB_SECT_TEX(x) ((x & 0x7) << 12)
463 #define TTB_SECT_DOMAIN(x) ((x & 0xf) << 5)
464 #define TTB_SECT_XN_MASK (1 << 4)
465 #define TTB_SECT_C_MASK (1 << 3)
466 #define TTB_SECT_B_MASK (1 << 2)
467 #define TTB_SECT (2 << 0)
468
469 /* options available for data cache on each page */
470 enum dcache_option {
471 DCACHE_OFF = TTB_SECT_DOMAIN(0) | TTB_SECT_XN_MASK | TTB_SECT,
472 DCACHE_WRITETHROUGH = DCACHE_OFF | TTB_SECT_C_MASK,
473 DCACHE_WRITEBACK = DCACHE_WRITETHROUGH | TTB_SECT_B_MASK,
474 DCACHE_WRITEALLOC = DCACHE_WRITEBACK | TTB_SECT_TEX(1),
475 };
476 #else
477 #define TTB_SECT_AP (3 << 10)
478 /* options available for data cache on each page */
479 enum dcache_option {
480 DCACHE_OFF = 0x12,
481 DCACHE_WRITETHROUGH = 0x1a,
482 DCACHE_WRITEBACK = 0x1e,
483 DCACHE_WRITEALLOC = 0x16,
484 };
485 #endif
486
487 /* Size of an MMU section */
488 enum {
489 #ifdef CONFIG_ARMV7_LPAE
490 MMU_SECTION_SHIFT = 21, /* 2MB */
491 #else
492 MMU_SECTION_SHIFT = 20, /* 1MB */
493 #endif
494 MMU_SECTION_SIZE = 1 << MMU_SECTION_SHIFT,
495 };
496
497 #ifdef CONFIG_CPU_V7A
498 /* TTBR0 bits */
499 #define TTBR0_BASE_ADDR_MASK 0xFFFFC000
500 #define TTBR0_RGN_NC (0 << 3)
501 #define TTBR0_RGN_WBWA (1 << 3)
502 #define TTBR0_RGN_WT (2 << 3)
503 #define TTBR0_RGN_WB (3 << 3)
504 /* TTBR0[6] is IRGN[0] and TTBR[0] is IRGN[1] */
505 #define TTBR0_IRGN_NC (0 << 0 | 0 << 6)
506 #define TTBR0_IRGN_WBWA (0 << 0 | 1 << 6)
507 #define TTBR0_IRGN_WT (1 << 0 | 0 << 6)
508 #define TTBR0_IRGN_WB (1 << 0 | 1 << 6)
509 #endif
510
511 /**
512 * Register an update to the page tables, and flush the TLB
513 *
514 * \param start start address of update in page table
515 * \param stop stop address of update in page table
516 */
517 void mmu_page_table_flush(unsigned long start, unsigned long stop);
518
519 #endif /* __ASSEMBLY__ */
520
521 #define arch_align_stack(x) (x)
522
523 #endif /* __KERNEL__ */
524
525 #endif /* CONFIG_ARM64 */
526
527 #ifndef __ASSEMBLY__
528 /**
529 * save_boot_params() - Save boot parameters before starting reset sequence
530 *
531 * If you provide this function it will be called immediately U-Boot starts,
532 * both for SPL and U-Boot proper.
533 *
534 * All registers are unchanged from U-Boot entry. No registers need be
535 * preserved.
536 *
537 * This is not a normal C function. There is no stack. Return by branching to
538 * save_boot_params_ret.
539 *
540 * void save_boot_params(u32 r0, u32 r1, u32 r2, u32 r3);
541 */
542
543 /**
544 * save_boot_params_ret() - Return from save_boot_params()
545 *
546 * If you provide save_boot_params(), then you should jump back to this
547 * function when done. Try to preserve all registers.
548 *
549 * If your implementation of save_boot_params() is in C then it is acceptable
550 * to simply call save_boot_params_ret() at the end of your function. Since
551 * there is no link register set up, you cannot just exit the function. U-Boot
552 * will return to the (initialised) value of lr, and likely crash/hang.
553 *
554 * If your implementation of save_boot_params() is in assembler then you
555 * should use 'b' or 'bx' to return to save_boot_params_ret.
556 */
557 void save_boot_params_ret(void);
558
559 /**
560 * Change the cache settings for a region.
561 *
562 * \param start start address of memory region to change
563 * \param size size of memory region to change
564 * \param option dcache option to select
565 */
566 void mmu_set_region_dcache_behaviour(phys_addr_t start, size_t size,
567 enum dcache_option option);
568
569 #ifdef CONFIG_SYS_NONCACHED_MEMORY
570 void noncached_init(void);
571 phys_addr_t noncached_alloc(size_t size, size_t align);
572 #endif /* CONFIG_SYS_NONCACHED_MEMORY */
573
574 #endif /* __ASSEMBLY__ */
575
576 #endif
577