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83d290c5 1/* SPDX-License-Identifier: GPL-2.0+ */
507bbe3e 2/*
cfc67116 3 * (C) Copyright 2007 Michal Simek
507bbe3e
WD
4 * (C) Copyright 2004 Atmark Techno, Inc.
5 *
cfc67116 6 * Michal SIMEK <monstr@monstr.eu>
507bbe3e 7 * Yasushi SHOJI <yashi@atmark-techno.com>
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WD
8 */
9
25ddd1fb 10#include <asm-offsets.h>
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11#include <config.h>
12
d58c0074
MS
13#define SYM_ADDR(reg, reg_add, symbol) \
14 mfs r20, rpc; \
15 addik r20, r20, _GLOBAL_OFFSET_TABLE_ + 8; \
16 lwi reg, r20, symbol@GOT; \
17 addk reg, reg reg_add;
07c052be 18
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WD
19 .text
20 .global _start
21_start:
cfc67116 22 mts rmsr, r0 /* disable cache */
b6fe10af
MS
23 mfs r20, rpc
24 addi r20, r20, -4
9d242745 25
16a18471 26 mts rslr, r0
b6fe10af 27 mts rshr, r20
f5d8b1a1 28
9d242745 29#if defined(CONFIG_SPL_BUILD)
f113d7d3 30 addi r1, r0, CONFIG_SPL_STACK
9d242745 31#else
b6fe10af 32 add r1, r0, r20
d58c0074
MS
33 bri 1f
34
35 /* Force alignment for easier ASM code below */
36#define ALIGNMENT_ADDR 0x20
37 .align 4
38uboot_dyn_start:
39 .word __rel_dyn_start
40
41uboot_dyn_end:
42 .word __rel_dyn_end
43
44uboot_sym_start:
45 .word __dyn_sym_start
461:
47
48 addi r5, r20, 0
49 add r6, r0, r0
50
51 lwi r7, r20, ALIGNMENT_ADDR
98463903 52 addi r7, r7, -CONFIG_TEXT_BASE
d58c0074
MS
53 add r7, r7, r5
54 lwi r8, r20, ALIGNMENT_ADDR + 0x4
98463903 55 addi r8, r8, -CONFIG_TEXT_BASE
d58c0074
MS
56 add r8, r8, r5
57 lwi r9, r20, ALIGNMENT_ADDR + 0x8
98463903 58 addi r9, r9, -CONFIG_TEXT_BASE
d58c0074 59 add r9, r9, r5
98463903 60 addi r10, r0, CONFIG_TEXT_BASE
d58c0074
MS
61
62 brlid r15, mb_fix_rela
63 nop
405e651d 64#endif
f5d8b1a1 65
17980495 66 addi r1, r1, -4 /* Decrement SP to top of memory */
b98cba09 67
f5d8b1a1
OP
68 /* Call board_init_f_alloc_reserve with the current stack pointer as
69 * parameter. */
70 add r5, r0, r1
7cf236cf 71 brlid r15, board_init_f_alloc_reserve
f5d8b1a1
OP
72 nop
73
74 /* board_init_f_alloc_reserve returns a pointer to the allocated area
75 * in r3. Set the new stack pointer below this area. */
76 add r1, r0, r3
77 mts rshr, r1
78 addi r1, r1, -4
79
80 /* Call board_init_f_init_reserve with the address returned by
81 * board_init_f_alloc_reserve as parameter. */
82 add r5, r0, r3
7cf236cf 83 brlid r15, board_init_f_init_reserve
f5d8b1a1
OP
84 nop
85
86#if !defined(CONFIG_SPL_BUILD)
627085ea
OP
87 /* Setup vectors with pre-relocation symbols */
88 or r5, r0, r0
7cf236cf 89 brlid r15, __setup_exceptions
627085ea 90 nop
f5d8b1a1 91#endif
627085ea 92
95b7a8fd
OP
93 /*
94 * Initialize global data cpuinfo with default values (cache
95 * size, cache line size, etc).
96 */
97 brlid r15, microblaze_early_cpuinfo_init
98 nop
99
627085ea 100 /* Flush cache before enable cache */
b1951349 101 brlid r15, flush_cache_all
627085ea
OP
102 nop
103
104 /* enable instruction and data cache */
105 mfs r12, rmsr
106 ori r12, r12, 0x1a0
107 mts rmsr, r12
108
627085ea
OP
109clear_bss:
110 /* clear BSS segments */
07c052be
MS
111 SYM_ADDR(r5, r0, __bss_start)
112 SYM_ADDR(r4, r0, __bss_end)
627085ea
OP
113 cmp r6, r5, r4
114 beqi r6, 3f
1152:
116 swi r0, r5, 0 /* write zero to loc */
117 addi r5, r5, 4 /* increment to next loc */
118 cmp r6, r5, r4 /* check if we have reach the end */
119 bnei r6, 2b
1203: /* jumping to board_init */
121#ifdef CONFIG_DEBUG_UART
7cf236cf 122 brlid r15, debug_uart_init
627085ea
OP
123 nop
124#endif
125#ifndef CONFIG_SPL_BUILD
126 or r5, r0, r0 /* flags - empty */
7cf236cf 127 bri board_init_f
627085ea 128#else
7cf236cf 129 bri board_init_r
627085ea
OP
130#endif
1311: bri 1b
132
627085ea
OP
133#ifndef CONFIG_SPL_BUILD
134 .text
135 .ent __setup_exceptions
136 .align 2
137/*
138 * Set up reset, interrupt, user exception and hardware exception vectors.
139 *
140 * Parameters:
141 * r5 - relocation offset (zero when setting up vectors before
142 * relocation, and gd->reloc_off when setting up vectors after
143 * relocation)
144 * - the relocation offset is added to the _exception_handler,
145 * _interrupt_handler and _hw_exception_handler symbols to reflect the
146 * post-relocation memory addresses
147 *
148 * Reserve registers:
149 * r10: Stores little/big endian offset for vectors
150 * r2: Stores imm opcode
151 * r3: Stores brai opcode
f149ee4c 152 * r4: Stores the vector base address
627085ea
OP
153 */
154__setup_exceptions:
f149ee4c 155 addik r1, r1, -32
627085ea
OP
156 swi r2, r1, 4
157 swi r3, r1, 8
f149ee4c
OP
158 swi r4, r1, 12
159 swi r6, r1, 16
160 swi r7, r1, 20
161 swi r8, r1, 24
162 swi r10, r1, 28
627085ea 163
b98cba09
MS
164 /* Find-out if u-boot is running on BIG/LITTLE endian platform
165 * There are some steps which is necessary to keep in mind:
166 * 1. Setup offset value to r6
167 * 2. Store word offset value to address 0x0
168 * 3. Load just byte from address 0x0
169 * 4a) LITTLE endian - r10 contains 0x2 because it is the smallest
170 * value that's why is on address 0x0
171 * 4b) BIG endian - r10 contains 0x0 because 0x2 offset is on addr 0x3
172 */
173 addik r6, r0, 0x2 /* BIG/LITTLE endian offset */
48039c33
OP
174 sw r6, r1, r0
175 lbu r10, r1, r0
b98cba09 176
86c1b2a8
MS
177 /* add opcode instruction for 32bit jump - 2 instruction imm & brai */
178 addi r2, r0, 0xb0000000 /* hex b000 opcode imm */
179 addi r3, r0, 0xb8080000 /* hew b808 opcode brai */
507bbe3e 180
f149ee4c
OP
181 /* Store the vector base address in r4 */
182 addi r4, r0, CONFIG_XILINX_MICROBLAZE0_VECTOR_BASE_ADDR
183
cfc67116 184 /* reset address */
f149ee4c
OP
185 swi r2, r4, 0x0 /* reset address - imm opcode */
186 swi r3, r4, 0x4 /* reset address - brai opcode */
86c1b2a8 187
07c052be 188 SYM_ADDR(r6, r0, _start)
81169ae6 189 /* Intentionally keep reset vector back to origin u-boot location */
cfc67116 190 sw r6, r1, r0
5562bcc2
MS
191 lhu r7, r1, r10
192 rsubi r8, r10, 0x2
f149ee4c 193 sh r7, r4, r8
5562bcc2 194 rsubi r8, r10, 0x6
f149ee4c 195 sh r6, r4, r8
cfc67116 196
83b175be 197#if CONFIG_IS_ENABLED(XILINX_MICROBLAZE0_USR_EXCEP)
cfc67116 198 /* user_vector_exception */
f149ee4c
OP
199 swi r2, r4, 0x8 /* user vector exception - imm opcode */
200 swi r3, r4, 0xC /* user vector exception - brai opcode */
86c1b2a8 201
07c052be 202 SYM_ADDR(r6, r5, _exception_handler)
cfc67116 203 sw r6, r1, r0
b98cba09
MS
204 /*
205 * BIG ENDIAN memory map for user exception
206 * 0x8: 0xB000XXXX
207 * 0xC: 0xB808XXXX
208 *
209 * then it is necessary to count address for storing the most significant
071bc923 210 * 16bits from _exception_handler address and copy it to
b98cba09
MS
211 * 0xa address. Big endian use offset in r10=0 that's why is it just
212 * 0xa address. The same is done for the least significant 16 bits
213 * for 0xe address.
214 *
215 * LITTLE ENDIAN memory map for user exception
216 * 0x8: 0xXXXX00B0
217 * 0xC: 0xXXXX08B8
218 *
219 * Offset is for little endian setup to 0x2. rsubi instruction decrease
220 * address value to ensure that points to proper place which is
221 * 0x8 for the most significant 16 bits and
222 * 0xC for the least significant 16 bits
223 */
224 lhu r7, r1, r10
225 rsubi r8, r10, 0xa
f149ee4c 226 sh r7, r4, r8
b98cba09 227 rsubi r8, r10, 0xe
f149ee4c 228 sh r6, r4, r8
cfc67116
MS
229#endif
230
cfc67116 231 /* interrupt_handler */
f149ee4c
OP
232 swi r2, r4, 0x10 /* interrupt - imm opcode */
233 swi r3, r4, 0x14 /* interrupt - brai opcode */
86c1b2a8 234
07c052be 235 SYM_ADDR(r6, r5, _interrupt_handler)
cfc67116 236 sw r6, r1, r0
b98cba09
MS
237 lhu r7, r1, r10
238 rsubi r8, r10, 0x12
f149ee4c 239 sh r7, r4, r8
b98cba09 240 rsubi r8, r10, 0x16
f149ee4c 241 sh r6, r4, r8
507bbe3e 242
cfc67116 243 /* hardware exception */
f149ee4c
OP
244 swi r2, r4, 0x20 /* hardware exception - imm opcode */
245 swi r3, r4, 0x24 /* hardware exception - brai opcode */
86c1b2a8 246
07c052be 247 SYM_ADDR(r6, r5, _hw_exception_handler)
cfc67116 248 sw r6, r1, r0
b98cba09
MS
249 lhu r7, r1, r10
250 rsubi r8, r10, 0x22
f149ee4c 251 sh r7, r4, r8
b98cba09 252 rsubi r8, r10, 0x26
f149ee4c 253 sh r6, r4, r8
cfc67116 254
f149ee4c
OP
255 lwi r10, r1, 28
256 lwi r8, r1, 24
257 lwi r7, r1, 20
258 lwi r6, r1, 16
259 lwi r4, r1, 12
627085ea
OP
260 lwi r3, r1, 8
261 lwi r2, r1, 4
f149ee4c 262 addik r1, r1, 32
0643631a 263
627085ea
OP
264 rtsd r15, 8
265 or r0, r0, r0
266 .end __setup_exceptions
0510b14b 267
e945f6dc
MS
268/*
269 * Relocate u-boot
270 */
271 .text
272 .global relocate_code
273 .ent relocate_code
274 .align 2
275relocate_code:
276 /*
277 * r5 - start_addr_sp
278 * r6 - new_gd
279 * r7 - reloc_addr
280 */
281 addi r1, r5, 0 /* Start to use new SP */
532ad5f8 282 mts rshr, r1
e945f6dc
MS
283 addi r31, r6, 0 /* Start to use new GD */
284
e945f6dc 285 /* Relocate text and data - r12 temp value */
07c052be
MS
286 SYM_ADDR(r21, r0, _start)
287 SYM_ADDR(r22, r0, _end) /* Include BSS too */
1918c416 288 addi r22, r22, -4
7c4dd542
MS
289
290 rsub r6, r21, r22
291 or r5, r0, r0
2921: lw r12, r21, r5 /* Load u-boot data */
3041b512 293 sw r12, r7, r5 /* Write zero to loc */
7c4dd542 294 cmp r12, r5, r6 /* Check if we have reach the end */
e945f6dc 295 bneid r12, 1b
7c4dd542 296 addi r5, r5, 4 /* Increment to next loc - relocate code */
e945f6dc 297
3ad95ed6 298 /* R23 points to the base address. */
3041b512 299 rsub r23, r21, r7 /* keep - this is already here gd->reloc_off */
e945f6dc 300
627085ea
OP
301 /* Setup vectors with post-relocation symbols */
302 add r5, r0, r23 /* load gd->reloc_off to r5 */
7cf236cf 303 brlid r15, __setup_exceptions
627085ea 304 nop
e945f6dc 305
d58c0074
MS
306 /* reloc_offset is current location */
307 SYM_ADDR(r10, r0, _start)
308
309 /* r5 new address where I should copy code */
310 add r5, r0, r7 /* Move reloc addr to r5 */
311
312 /* Verbose message */
313 addi r6, r0, 0
314
315 SYM_ADDR(r7, r0, __rel_dyn_start)
316 rsub r7, r10, r7
317 add r7, r7, r5
318 SYM_ADDR(r8, r0, __rel_dyn_end)
319 rsub r8, r10, r8
320 add r8, r8, r5
321 SYM_ADDR(r9, r0, __dyn_sym_start)
322 rsub r9, r10, r9
323 add r9, r9, r5
324 brlid r15, mb_fix_rela
627085ea 325 nop
d58c0074 326 /* end of code which does relocation */
e945f6dc
MS
327
328 /* Flush caches to ensure consistency */
b1951349 329 brlid r15, flush_cache_all
e945f6dc
MS
330 nop
331
3322: addi r5, r31, 0 /* gd is initialized in board_r.c */
07c052be
MS
333 SYM_ADDR(r6, r0, _start)
334 SYM_ADDR(r12, r23, board_init_r)
e945f6dc
MS
335 bra r12 /* Jump to relocated code */
336
337 .end relocate_code
9d242745 338#endif