Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * linux/arch/arm/boot/compressed/head.S |
| 3 | * |
| 4 | * Copyright (C) 1996-2002 Russell King |
Hyok S. Choi | 10c2df6 | 2006-03-27 10:21:34 +0100 | [diff] [blame] | 5 | * Copyright (C) 2004 Hyok S. Choi (MPU support) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 6 | * |
| 7 | * This program is free software; you can redistribute it and/or modify |
| 8 | * it under the terms of the GNU General Public License version 2 as |
| 9 | * published by the Free Software Foundation. |
| 10 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 11 | #include <linux/linkage.h> |
| 12 | |
| 13 | /* |
| 14 | * Debugging stuff |
| 15 | * |
| 16 | * Note that these macros must not contain any code which is not |
| 17 | * 100% relocatable. Any attempt to do so will result in a crash. |
| 18 | * Please select one of the following when turning on debugging. |
| 19 | */ |
| 20 | #ifdef DEBUG |
Russell King | 5cd0c34 | 2005-05-03 12:18:46 +0100 | [diff] [blame] | 21 | |
Russell King | 5cd0c34 | 2005-05-03 12:18:46 +0100 | [diff] [blame] | 22 | #if defined(CONFIG_DEBUG_ICEDCC) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 23 | .macro loadsp, rb |
| 24 | .endm |
Russell King | 224b5be | 2005-11-16 14:59:51 +0000 | [diff] [blame] | 25 | .macro writeb, ch, rb |
Russell King | 5cd0c34 | 2005-05-03 12:18:46 +0100 | [diff] [blame] | 26 | mcr p14, 0, \ch, c0, c1, 0 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 27 | .endm |
Russell King | 5cd0c34 | 2005-05-03 12:18:46 +0100 | [diff] [blame] | 28 | #else |
Russell King | 224b5be | 2005-11-16 14:59:51 +0000 | [diff] [blame] | 29 | |
| 30 | #include <asm/arch/debug-macro.S> |
| 31 | |
Russell King | 5cd0c34 | 2005-05-03 12:18:46 +0100 | [diff] [blame] | 32 | .macro writeb, ch, rb |
| 33 | senduart \ch, \rb |
| 34 | .endm |
| 35 | |
Russell King | 224b5be | 2005-11-16 14:59:51 +0000 | [diff] [blame] | 36 | #if defined(CONFIG_ARCH_SA1100) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 37 | .macro loadsp, rb |
| 38 | mov \rb, #0x80000000 @ physical base address |
Russell King | 224b5be | 2005-11-16 14:59:51 +0000 | [diff] [blame] | 39 | #ifdef CONFIG_DEBUG_LL_SER3 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 40 | add \rb, \rb, #0x00050000 @ Ser3 |
Russell King | 224b5be | 2005-11-16 14:59:51 +0000 | [diff] [blame] | 41 | #else |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 42 | add \rb, \rb, #0x00010000 @ Ser1 |
Russell King | 224b5be | 2005-11-16 14:59:51 +0000 | [diff] [blame] | 43 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 44 | .endm |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 45 | #elif defined(CONFIG_ARCH_IOP331) |
| 46 | .macro loadsp, rb |
| 47 | mov \rb, #0xff000000 |
| 48 | orr \rb, \rb, #0x00ff0000 |
| 49 | orr \rb, \rb, #0x0000f700 @ location of the UART |
| 50 | .endm |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 51 | #elif defined(CONFIG_ARCH_S3C2410) |
Russell King | 5cd0c34 | 2005-05-03 12:18:46 +0100 | [diff] [blame] | 52 | .macro loadsp, rb |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 53 | mov \rb, #0x50000000 |
| 54 | add \rb, \rb, #0x4000 * CONFIG_S3C2410_LOWLEVEL_UART_PORT |
| 55 | .endm |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 56 | #else |
Russell King | 224b5be | 2005-11-16 14:59:51 +0000 | [diff] [blame] | 57 | .macro loadsp, rb |
| 58 | addruart \rb |
| 59 | .endm |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 60 | #endif |
| 61 | #endif |
Russell King | 5cd0c34 | 2005-05-03 12:18:46 +0100 | [diff] [blame] | 62 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 63 | |
| 64 | .macro kputc,val |
| 65 | mov r0, \val |
| 66 | bl putc |
| 67 | .endm |
| 68 | |
| 69 | .macro kphex,val,len |
| 70 | mov r0, \val |
| 71 | mov r1, #\len |
| 72 | bl phex |
| 73 | .endm |
| 74 | |
| 75 | .macro debug_reloc_start |
| 76 | #ifdef DEBUG |
| 77 | kputc #'\n' |
| 78 | kphex r6, 8 /* processor id */ |
| 79 | kputc #':' |
| 80 | kphex r7, 8 /* architecture id */ |
| 81 | kputc #':' |
| 82 | mrc p15, 0, r0, c1, c0 |
| 83 | kphex r0, 8 /* control reg */ |
| 84 | kputc #'\n' |
| 85 | kphex r5, 8 /* decompressed kernel start */ |
| 86 | kputc #'-' |
Russell King | f461902 | 2006-01-12 17:17:57 +0000 | [diff] [blame] | 87 | kphex r9, 8 /* decompressed kernel end */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 88 | kputc #'>' |
| 89 | kphex r4, 8 /* kernel execution address */ |
| 90 | kputc #'\n' |
| 91 | #endif |
| 92 | .endm |
| 93 | |
| 94 | .macro debug_reloc_end |
| 95 | #ifdef DEBUG |
| 96 | kphex r5, 8 /* end of kernel */ |
| 97 | kputc #'\n' |
| 98 | mov r0, r4 |
| 99 | bl memdump /* dump 256 bytes at start of kernel */ |
| 100 | #endif |
| 101 | .endm |
| 102 | |
| 103 | .section ".start", #alloc, #execinstr |
| 104 | /* |
| 105 | * sort out different calling conventions |
| 106 | */ |
| 107 | .align |
| 108 | start: |
| 109 | .type start,#function |
| 110 | .rept 8 |
| 111 | mov r0, r0 |
| 112 | .endr |
| 113 | |
| 114 | b 1f |
| 115 | .word 0x016f2818 @ Magic numbers to help the loader |
| 116 | .word start @ absolute load/run zImage address |
| 117 | .word _edata @ zImage end address |
| 118 | 1: mov r7, r1 @ save architecture ID |
Russell King | f461902 | 2006-01-12 17:17:57 +0000 | [diff] [blame] | 119 | mov r8, r2 @ save atags pointer |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 120 | |
| 121 | #ifndef __ARM_ARCH_2__ |
| 122 | /* |
| 123 | * Booting from Angel - need to enter SVC mode and disable |
| 124 | * FIQs/IRQs (numeric definitions from angel arm.h source). |
| 125 | * We only do this if we were in user mode on entry. |
| 126 | */ |
| 127 | mrs r2, cpsr @ get current mode |
| 128 | tst r2, #3 @ not user? |
| 129 | bne not_angel |
| 130 | mov r0, #0x17 @ angel_SWIreason_EnterSVC |
| 131 | swi 0x123456 @ angel_SWI_ARM |
| 132 | not_angel: |
| 133 | mrs r2, cpsr @ turn off interrupts to |
| 134 | orr r2, r2, #0xc0 @ prevent angel from running |
| 135 | msr cpsr_c, r2 |
| 136 | #else |
| 137 | teqp pc, #0x0c000003 @ turn off interrupts |
| 138 | #endif |
| 139 | |
| 140 | /* |
| 141 | * Note that some cache flushing and other stuff may |
| 142 | * be needed here - is there an Angel SWI call for this? |
| 143 | */ |
| 144 | |
| 145 | /* |
| 146 | * some architecture specific code can be inserted |
Russell King | f461902 | 2006-01-12 17:17:57 +0000 | [diff] [blame] | 147 | * by the linker here, but it should preserve r7, r8, and r9. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 148 | */ |
| 149 | |
| 150 | .text |
| 151 | adr r0, LC0 |
| 152 | ldmia r0, {r1, r2, r3, r4, r5, r6, ip, sp} |
| 153 | subs r0, r0, r1 @ calculate the delta offset |
| 154 | |
| 155 | @ if delta is zero, we are |
| 156 | beq not_relocated @ running at the address we |
| 157 | @ were linked at. |
| 158 | |
| 159 | /* |
| 160 | * We're running at a different address. We need to fix |
| 161 | * up various pointers: |
| 162 | * r5 - zImage base address |
| 163 | * r6 - GOT start |
| 164 | * ip - GOT end |
| 165 | */ |
| 166 | add r5, r5, r0 |
| 167 | add r6, r6, r0 |
| 168 | add ip, ip, r0 |
| 169 | |
| 170 | #ifndef CONFIG_ZBOOT_ROM |
| 171 | /* |
| 172 | * If we're running fully PIC === CONFIG_ZBOOT_ROM = n, |
| 173 | * we need to fix up pointers into the BSS region. |
| 174 | * r2 - BSS start |
| 175 | * r3 - BSS end |
| 176 | * sp - stack pointer |
| 177 | */ |
| 178 | add r2, r2, r0 |
| 179 | add r3, r3, r0 |
| 180 | add sp, sp, r0 |
| 181 | |
| 182 | /* |
| 183 | * Relocate all entries in the GOT table. |
| 184 | */ |
| 185 | 1: ldr r1, [r6, #0] @ relocate entries in the GOT |
| 186 | add r1, r1, r0 @ table. This fixes up the |
| 187 | str r1, [r6], #4 @ C references. |
| 188 | cmp r6, ip |
| 189 | blo 1b |
| 190 | #else |
| 191 | |
| 192 | /* |
| 193 | * Relocate entries in the GOT table. We only relocate |
| 194 | * the entries that are outside the (relocated) BSS region. |
| 195 | */ |
| 196 | 1: ldr r1, [r6, #0] @ relocate entries in the GOT |
| 197 | cmp r1, r2 @ entry < bss_start || |
| 198 | cmphs r3, r1 @ _end < entry |
| 199 | addlo r1, r1, r0 @ table. This fixes up the |
| 200 | str r1, [r6], #4 @ C references. |
| 201 | cmp r6, ip |
| 202 | blo 1b |
| 203 | #endif |
| 204 | |
| 205 | not_relocated: mov r0, #0 |
| 206 | 1: str r0, [r2], #4 @ clear bss |
| 207 | str r0, [r2], #4 |
| 208 | str r0, [r2], #4 |
| 209 | str r0, [r2], #4 |
| 210 | cmp r2, r3 |
| 211 | blo 1b |
| 212 | |
| 213 | /* |
| 214 | * The C runtime environment should now be setup |
| 215 | * sufficiently. Turn the cache on, set up some |
| 216 | * pointers, and start decompressing. |
| 217 | */ |
| 218 | bl cache_on |
| 219 | |
| 220 | mov r1, sp @ malloc space above stack |
| 221 | add r2, sp, #0x10000 @ 64k max |
| 222 | |
| 223 | /* |
| 224 | * Check to see if we will overwrite ourselves. |
| 225 | * r4 = final kernel address |
| 226 | * r5 = start of this image |
| 227 | * r2 = end of malloc space (and therefore this image) |
| 228 | * We basically want: |
| 229 | * r4 >= r2 -> OK |
| 230 | * r4 + image length <= r5 -> OK |
| 231 | */ |
| 232 | cmp r4, r2 |
| 233 | bhs wont_overwrite |
| 234 | add r0, r4, #4096*1024 @ 4MB largest kernel size |
| 235 | cmp r0, r5 |
| 236 | bls wont_overwrite |
| 237 | |
| 238 | mov r5, r2 @ decompress after malloc space |
| 239 | mov r0, r5 |
| 240 | mov r3, r7 |
| 241 | bl decompress_kernel |
| 242 | |
| 243 | add r0, r0, #127 |
| 244 | bic r0, r0, #127 @ align the kernel length |
| 245 | /* |
| 246 | * r0 = decompressed kernel length |
| 247 | * r1-r3 = unused |
| 248 | * r4 = kernel execution address |
| 249 | * r5 = decompressed kernel start |
| 250 | * r6 = processor ID |
| 251 | * r7 = architecture ID |
Russell King | f461902 | 2006-01-12 17:17:57 +0000 | [diff] [blame] | 252 | * r8 = atags pointer |
| 253 | * r9-r14 = corrupted |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 254 | */ |
| 255 | add r1, r5, r0 @ end of decompressed kernel |
| 256 | adr r2, reloc_start |
| 257 | ldr r3, LC1 |
| 258 | add r3, r2, r3 |
Russell King | f461902 | 2006-01-12 17:17:57 +0000 | [diff] [blame] | 259 | 1: ldmia r2!, {r9 - r14} @ copy relocation code |
| 260 | stmia r1!, {r9 - r14} |
| 261 | ldmia r2!, {r9 - r14} |
| 262 | stmia r1!, {r9 - r14} |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 263 | cmp r2, r3 |
| 264 | blo 1b |
| 265 | |
| 266 | bl cache_clean_flush |
| 267 | add pc, r5, r0 @ call relocation code |
| 268 | |
| 269 | /* |
| 270 | * We're not in danger of overwriting ourselves. Do this the simple way. |
| 271 | * |
| 272 | * r4 = kernel execution address |
| 273 | * r7 = architecture ID |
| 274 | */ |
| 275 | wont_overwrite: mov r0, r4 |
| 276 | mov r3, r7 |
| 277 | bl decompress_kernel |
| 278 | b call_kernel |
| 279 | |
| 280 | .type LC0, #object |
| 281 | LC0: .word LC0 @ r1 |
| 282 | .word __bss_start @ r2 |
| 283 | .word _end @ r3 |
| 284 | .word zreladdr @ r4 |
| 285 | .word _start @ r5 |
| 286 | .word _got_start @ r6 |
| 287 | .word _got_end @ ip |
| 288 | .word user_stack+4096 @ sp |
| 289 | LC1: .word reloc_end - reloc_start |
| 290 | .size LC0, . - LC0 |
| 291 | |
| 292 | #ifdef CONFIG_ARCH_RPC |
| 293 | .globl params |
| 294 | params: ldr r0, =params_phys |
| 295 | mov pc, lr |
| 296 | .ltorg |
| 297 | .align |
| 298 | #endif |
| 299 | |
| 300 | /* |
| 301 | * Turn on the cache. We need to setup some page tables so that we |
| 302 | * can have both the I and D caches on. |
| 303 | * |
| 304 | * We place the page tables 16k down from the kernel execution address, |
| 305 | * and we hope that nothing else is using it. If we're using it, we |
| 306 | * will go pop! |
| 307 | * |
| 308 | * On entry, |
| 309 | * r4 = kernel execution address |
| 310 | * r6 = processor ID |
| 311 | * r7 = architecture number |
Russell King | f461902 | 2006-01-12 17:17:57 +0000 | [diff] [blame] | 312 | * r8 = atags pointer |
| 313 | * r9 = run-time address of "start" (???) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 314 | * On exit, |
Russell King | f461902 | 2006-01-12 17:17:57 +0000 | [diff] [blame] | 315 | * r1, r2, r3, r9, r10, r12 corrupted |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 316 | * This routine must preserve: |
Russell King | f461902 | 2006-01-12 17:17:57 +0000 | [diff] [blame] | 317 | * r4, r5, r6, r7, r8 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 318 | */ |
| 319 | .align 5 |
| 320 | cache_on: mov r3, #8 @ cache_on function |
| 321 | b call_cache_fn |
| 322 | |
Hyok S. Choi | 10c2df6 | 2006-03-27 10:21:34 +0100 | [diff] [blame] | 323 | /* |
| 324 | * Initialize the highest priority protection region, PR7 |
| 325 | * to cover all 32bit address and cacheable and bufferable. |
| 326 | */ |
| 327 | __armv4_mpu_cache_on: |
| 328 | mov r0, #0x3f @ 4G, the whole |
| 329 | mcr p15, 0, r0, c6, c7, 0 @ PR7 Area Setting |
| 330 | mcr p15, 0, r0, c6, c7, 1 |
| 331 | |
| 332 | mov r0, #0x80 @ PR7 |
| 333 | mcr p15, 0, r0, c2, c0, 0 @ D-cache on |
| 334 | mcr p15, 0, r0, c2, c0, 1 @ I-cache on |
| 335 | mcr p15, 0, r0, c3, c0, 0 @ write-buffer on |
| 336 | |
| 337 | mov r0, #0xc000 |
| 338 | mcr p15, 0, r0, c5, c0, 1 @ I-access permission |
| 339 | mcr p15, 0, r0, c5, c0, 0 @ D-access permission |
| 340 | |
| 341 | mov r0, #0 |
| 342 | mcr p15, 0, r0, c7, c10, 4 @ drain write buffer |
| 343 | mcr p15, 0, r0, c7, c5, 0 @ flush(inval) I-Cache |
| 344 | mcr p15, 0, r0, c7, c6, 0 @ flush(inval) D-Cache |
| 345 | mrc p15, 0, r0, c1, c0, 0 @ read control reg |
| 346 | @ ...I .... ..D. WC.M |
| 347 | orr r0, r0, #0x002d @ .... .... ..1. 11.1 |
| 348 | orr r0, r0, #0x1000 @ ...1 .... .... .... |
| 349 | |
| 350 | mcr p15, 0, r0, c1, c0, 0 @ write control reg |
| 351 | |
| 352 | mov r0, #0 |
| 353 | mcr p15, 0, r0, c7, c5, 0 @ flush(inval) I-Cache |
| 354 | mcr p15, 0, r0, c7, c6, 0 @ flush(inval) D-Cache |
| 355 | mov pc, lr |
| 356 | |
| 357 | __armv3_mpu_cache_on: |
| 358 | mov r0, #0x3f @ 4G, the whole |
| 359 | mcr p15, 0, r0, c6, c7, 0 @ PR7 Area Setting |
| 360 | |
| 361 | mov r0, #0x80 @ PR7 |
| 362 | mcr p15, 0, r0, c2, c0, 0 @ cache on |
| 363 | mcr p15, 0, r0, c3, c0, 0 @ write-buffer on |
| 364 | |
| 365 | mov r0, #0xc000 |
| 366 | mcr p15, 0, r0, c5, c0, 0 @ access permission |
| 367 | |
| 368 | mov r0, #0 |
| 369 | mcr p15, 0, r0, c7, c0, 0 @ invalidate whole cache v3 |
| 370 | mrc p15, 0, r0, c1, c0, 0 @ read control reg |
| 371 | @ .... .... .... WC.M |
| 372 | orr r0, r0, #0x000d @ .... .... .... 11.1 |
| 373 | mov r0, #0 |
| 374 | mcr p15, 0, r0, c1, c0, 0 @ write control reg |
| 375 | |
| 376 | mcr p15, 0, r0, c7, c0, 0 @ invalidate whole cache v3 |
| 377 | mov pc, lr |
| 378 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 379 | __setup_mmu: sub r3, r4, #16384 @ Page directory size |
| 380 | bic r3, r3, #0xff @ Align the pointer |
| 381 | bic r3, r3, #0x3f00 |
| 382 | /* |
| 383 | * Initialise the page tables, turning on the cacheable and bufferable |
| 384 | * bits for the RAM area only. |
| 385 | */ |
| 386 | mov r0, r3 |
Russell King | f461902 | 2006-01-12 17:17:57 +0000 | [diff] [blame] | 387 | mov r9, r0, lsr #18 |
| 388 | mov r9, r9, lsl #18 @ start of RAM |
| 389 | add r10, r9, #0x10000000 @ a reasonable RAM size |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 390 | mov r1, #0x12 |
| 391 | orr r1, r1, #3 << 10 |
| 392 | add r2, r3, #16384 |
Nicolas Pitre | 265d5e4 | 2006-01-18 22:38:51 +0000 | [diff] [blame] | 393 | 1: cmp r1, r9 @ if virt > start of RAM |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 394 | orrhs r1, r1, #0x0c @ set cacheable, bufferable |
Russell King | f461902 | 2006-01-12 17:17:57 +0000 | [diff] [blame] | 395 | cmp r1, r10 @ if virt > end of RAM |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 396 | bichs r1, r1, #0x0c @ clear cacheable, bufferable |
| 397 | str r1, [r0], #4 @ 1:1 mapping |
| 398 | add r1, r1, #1048576 |
| 399 | teq r0, r2 |
| 400 | bne 1b |
| 401 | /* |
| 402 | * If ever we are running from Flash, then we surely want the cache |
| 403 | * to be enabled also for our execution instance... We map 2MB of it |
| 404 | * so there is no map overlap problem for up to 1 MB compressed kernel. |
| 405 | * If the execution is in RAM then we would only be duplicating the above. |
| 406 | */ |
| 407 | mov r1, #0x1e |
| 408 | orr r1, r1, #3 << 10 |
| 409 | mov r2, pc, lsr #20 |
| 410 | orr r1, r1, r2, lsl #20 |
| 411 | add r0, r3, r2, lsl #2 |
| 412 | str r1, [r0], #4 |
| 413 | add r1, r1, #1048576 |
| 414 | str r1, [r0] |
| 415 | mov pc, lr |
| 416 | |
Hyok S. Choi | c76b6b4 | 2006-03-24 09:53:18 +0000 | [diff] [blame] | 417 | __armv4_mmu_cache_on: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 418 | mov r12, lr |
| 419 | bl __setup_mmu |
| 420 | mov r0, #0 |
| 421 | mcr p15, 0, r0, c7, c10, 4 @ drain write buffer |
| 422 | mcr p15, 0, r0, c8, c7, 0 @ flush I,D TLBs |
| 423 | mrc p15, 0, r0, c1, c0, 0 @ read control reg |
| 424 | orr r0, r0, #0x5000 @ I-cache enable, RR cache replacement |
| 425 | orr r0, r0, #0x0030 |
Hyok S. Choi | c76b6b4 | 2006-03-24 09:53:18 +0000 | [diff] [blame] | 426 | bl __common_mmu_cache_on |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 427 | mov r0, #0 |
| 428 | mcr p15, 0, r0, c8, c7, 0 @ flush I,D TLBs |
| 429 | mov pc, r12 |
| 430 | |
Hyok S. Choi | c76b6b4 | 2006-03-24 09:53:18 +0000 | [diff] [blame] | 431 | __arm6_mmu_cache_on: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 432 | mov r12, lr |
| 433 | bl __setup_mmu |
| 434 | mov r0, #0 |
| 435 | mcr p15, 0, r0, c7, c0, 0 @ invalidate whole cache v3 |
| 436 | mcr p15, 0, r0, c5, c0, 0 @ invalidate whole TLB v3 |
| 437 | mov r0, #0x30 |
Hyok S. Choi | c76b6b4 | 2006-03-24 09:53:18 +0000 | [diff] [blame] | 438 | bl __common_mmu_cache_on |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 439 | mov r0, #0 |
| 440 | mcr p15, 0, r0, c5, c0, 0 @ invalidate whole TLB v3 |
| 441 | mov pc, r12 |
| 442 | |
Hyok S. Choi | c76b6b4 | 2006-03-24 09:53:18 +0000 | [diff] [blame] | 443 | __common_mmu_cache_on: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 444 | #ifndef DEBUG |
| 445 | orr r0, r0, #0x000d @ Write buffer, mmu |
| 446 | #endif |
| 447 | mov r1, #-1 |
| 448 | mcr p15, 0, r3, c2, c0, 0 @ load page table pointer |
| 449 | mcr p15, 0, r1, c3, c0, 0 @ load domain access control |
| 450 | mcr p15, 0, r0, c1, c0, 0 @ load control register |
| 451 | mov pc, lr |
| 452 | |
| 453 | /* |
| 454 | * All code following this line is relocatable. It is relocated by |
| 455 | * the above code to the end of the decompressed kernel image and |
| 456 | * executed there. During this time, we have no stacks. |
| 457 | * |
| 458 | * r0 = decompressed kernel length |
| 459 | * r1-r3 = unused |
| 460 | * r4 = kernel execution address |
| 461 | * r5 = decompressed kernel start |
| 462 | * r6 = processor ID |
| 463 | * r7 = architecture ID |
Russell King | f461902 | 2006-01-12 17:17:57 +0000 | [diff] [blame] | 464 | * r8 = atags pointer |
| 465 | * r9-r14 = corrupted |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 466 | */ |
| 467 | .align 5 |
Russell King | f461902 | 2006-01-12 17:17:57 +0000 | [diff] [blame] | 468 | reloc_start: add r9, r5, r0 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 469 | debug_reloc_start |
| 470 | mov r1, r4 |
| 471 | 1: |
| 472 | .rept 4 |
Russell King | f461902 | 2006-01-12 17:17:57 +0000 | [diff] [blame] | 473 | ldmia r5!, {r0, r2, r3, r10 - r14} @ relocate kernel |
| 474 | stmia r1!, {r0, r2, r3, r10 - r14} |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 475 | .endr |
| 476 | |
Russell King | f461902 | 2006-01-12 17:17:57 +0000 | [diff] [blame] | 477 | cmp r5, r9 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 478 | blo 1b |
| 479 | debug_reloc_end |
| 480 | |
| 481 | call_kernel: bl cache_clean_flush |
| 482 | bl cache_off |
Russell King | f461902 | 2006-01-12 17:17:57 +0000 | [diff] [blame] | 483 | mov r0, #0 @ must be zero |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 484 | mov r1, r7 @ restore architecture number |
Russell King | f461902 | 2006-01-12 17:17:57 +0000 | [diff] [blame] | 485 | mov r2, r8 @ restore atags pointer |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 486 | mov pc, r4 @ call kernel |
| 487 | |
| 488 | /* |
| 489 | * Here follow the relocatable cache support functions for the |
| 490 | * various processors. This is a generic hook for locating an |
| 491 | * entry and jumping to an instruction at the specified offset |
| 492 | * from the start of the block. Please note this is all position |
| 493 | * independent code. |
| 494 | * |
| 495 | * r1 = corrupted |
| 496 | * r2 = corrupted |
| 497 | * r3 = block offset |
| 498 | * r6 = corrupted |
| 499 | * r12 = corrupted |
| 500 | */ |
| 501 | |
| 502 | call_cache_fn: adr r12, proc_types |
| 503 | mrc p15, 0, r6, c0, c0 @ get processor ID |
| 504 | 1: ldr r1, [r12, #0] @ get value |
| 505 | ldr r2, [r12, #4] @ get mask |
| 506 | eor r1, r1, r6 @ (real ^ match) |
| 507 | tst r1, r2 @ & mask |
| 508 | addeq pc, r12, r3 @ call cache function |
| 509 | add r12, r12, #4*5 |
| 510 | b 1b |
| 511 | |
| 512 | /* |
| 513 | * Table for cache operations. This is basically: |
| 514 | * - CPU ID match |
| 515 | * - CPU ID mask |
| 516 | * - 'cache on' method instruction |
| 517 | * - 'cache off' method instruction |
| 518 | * - 'cache flush' method instruction |
| 519 | * |
| 520 | * We match an entry using: ((real_id ^ match) & mask) == 0 |
| 521 | * |
| 522 | * Writethrough caches generally only need 'on' and 'off' |
| 523 | * methods. Writeback caches _must_ have the flush method |
| 524 | * defined. |
| 525 | */ |
| 526 | .type proc_types,#object |
| 527 | proc_types: |
| 528 | .word 0x41560600 @ ARM6/610 |
| 529 | .word 0xffffffe0 |
Hyok S. Choi | c76b6b4 | 2006-03-24 09:53:18 +0000 | [diff] [blame] | 530 | b __arm6_mmu_cache_off @ works, but slow |
| 531 | b __arm6_mmu_cache_off |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 532 | mov pc, lr |
Hyok S. Choi | c76b6b4 | 2006-03-24 09:53:18 +0000 | [diff] [blame] | 533 | @ b __arm6_mmu_cache_on @ untested |
| 534 | @ b __arm6_mmu_cache_off |
| 535 | @ b __armv3_mmu_cache_flush |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 536 | |
| 537 | .word 0x00000000 @ old ARM ID |
| 538 | .word 0x0000f000 |
| 539 | mov pc, lr |
| 540 | mov pc, lr |
| 541 | mov pc, lr |
| 542 | |
| 543 | .word 0x41007000 @ ARM7/710 |
| 544 | .word 0xfff8fe00 |
Hyok S. Choi | c76b6b4 | 2006-03-24 09:53:18 +0000 | [diff] [blame] | 545 | b __arm7_mmu_cache_off |
| 546 | b __arm7_mmu_cache_off |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 547 | mov pc, lr |
| 548 | |
| 549 | .word 0x41807200 @ ARM720T (writethrough) |
| 550 | .word 0xffffff00 |
Hyok S. Choi | c76b6b4 | 2006-03-24 09:53:18 +0000 | [diff] [blame] | 551 | b __armv4_mmu_cache_on |
| 552 | b __armv4_mmu_cache_off |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 553 | mov pc, lr |
| 554 | |
Hyok S. Choi | 10c2df6 | 2006-03-27 10:21:34 +0100 | [diff] [blame] | 555 | .word 0x41007400 @ ARM74x |
| 556 | .word 0xff00ff00 |
| 557 | b __armv3_mpu_cache_on |
| 558 | b __armv3_mpu_cache_off |
| 559 | b __armv3_mpu_cache_flush |
| 560 | |
| 561 | .word 0x41009400 @ ARM94x |
| 562 | .word 0xff00ff00 |
| 563 | b __armv4_mpu_cache_on |
| 564 | b __armv4_mpu_cache_off |
| 565 | b __armv4_mpu_cache_flush |
| 566 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 567 | .word 0x00007000 @ ARM7 IDs |
| 568 | .word 0x0000f000 |
| 569 | mov pc, lr |
| 570 | mov pc, lr |
| 571 | mov pc, lr |
| 572 | |
| 573 | @ Everything from here on will be the new ID system. |
| 574 | |
| 575 | .word 0x4401a100 @ sa110 / sa1100 |
| 576 | .word 0xffffffe0 |
Hyok S. Choi | c76b6b4 | 2006-03-24 09:53:18 +0000 | [diff] [blame] | 577 | b __armv4_mmu_cache_on |
| 578 | b __armv4_mmu_cache_off |
| 579 | b __armv4_mmu_cache_flush |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 580 | |
| 581 | .word 0x6901b110 @ sa1110 |
| 582 | .word 0xfffffff0 |
Hyok S. Choi | c76b6b4 | 2006-03-24 09:53:18 +0000 | [diff] [blame] | 583 | b __armv4_mmu_cache_on |
| 584 | b __armv4_mmu_cache_off |
| 585 | b __armv4_mmu_cache_flush |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 586 | |
| 587 | @ These match on the architecture ID |
| 588 | |
| 589 | .word 0x00020000 @ ARMv4T |
| 590 | .word 0x000f0000 |
Hyok S. Choi | c76b6b4 | 2006-03-24 09:53:18 +0000 | [diff] [blame] | 591 | b __armv4_mmu_cache_on |
| 592 | b __armv4_mmu_cache_off |
| 593 | b __armv4_mmu_cache_flush |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 594 | |
| 595 | .word 0x00050000 @ ARMv5TE |
| 596 | .word 0x000f0000 |
Hyok S. Choi | c76b6b4 | 2006-03-24 09:53:18 +0000 | [diff] [blame] | 597 | b __armv4_mmu_cache_on |
| 598 | b __armv4_mmu_cache_off |
| 599 | b __armv4_mmu_cache_flush |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 600 | |
| 601 | .word 0x00060000 @ ARMv5TEJ |
| 602 | .word 0x000f0000 |
Hyok S. Choi | c76b6b4 | 2006-03-24 09:53:18 +0000 | [diff] [blame] | 603 | b __armv4_mmu_cache_on |
| 604 | b __armv4_mmu_cache_off |
| 605 | b __armv4_mmu_cache_flush |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 606 | |
Catalin Marinas | 45a7b9c | 2006-06-18 16:21:50 +0100 | [diff] [blame] | 607 | .word 0x0007b000 @ ARMv6 |
| 608 | .word 0x0007f000 |
Hyok S. Choi | c76b6b4 | 2006-03-24 09:53:18 +0000 | [diff] [blame] | 609 | b __armv4_mmu_cache_on |
| 610 | b __armv4_mmu_cache_off |
| 611 | b __armv6_mmu_cache_flush |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 612 | |
| 613 | .word 0 @ unrecognised type |
| 614 | .word 0 |
| 615 | mov pc, lr |
| 616 | mov pc, lr |
| 617 | mov pc, lr |
| 618 | |
| 619 | .size proc_types, . - proc_types |
| 620 | |
| 621 | /* |
| 622 | * Turn off the Cache and MMU. ARMv3 does not support |
| 623 | * reading the control register, but ARMv4 does. |
| 624 | * |
| 625 | * On entry, r6 = processor ID |
| 626 | * On exit, r0, r1, r2, r3, r12 corrupted |
| 627 | * This routine must preserve: r4, r6, r7 |
| 628 | */ |
| 629 | .align 5 |
| 630 | cache_off: mov r3, #12 @ cache_off function |
| 631 | b call_cache_fn |
| 632 | |
Hyok S. Choi | 10c2df6 | 2006-03-27 10:21:34 +0100 | [diff] [blame] | 633 | __armv4_mpu_cache_off: |
| 634 | mrc p15, 0, r0, c1, c0 |
| 635 | bic r0, r0, #0x000d |
| 636 | mcr p15, 0, r0, c1, c0 @ turn MPU and cache off |
| 637 | mov r0, #0 |
| 638 | mcr p15, 0, r0, c7, c10, 4 @ drain write buffer |
| 639 | mcr p15, 0, r0, c7, c6, 0 @ flush D-Cache |
| 640 | mcr p15, 0, r0, c7, c5, 0 @ flush I-Cache |
| 641 | mov pc, lr |
| 642 | |
| 643 | __armv3_mpu_cache_off: |
| 644 | mrc p15, 0, r0, c1, c0 |
| 645 | bic r0, r0, #0x000d |
| 646 | mcr p15, 0, r0, c1, c0, 0 @ turn MPU and cache off |
| 647 | mov r0, #0 |
| 648 | mcr p15, 0, r0, c7, c0, 0 @ invalidate whole cache v3 |
| 649 | mov pc, lr |
| 650 | |
Hyok S. Choi | c76b6b4 | 2006-03-24 09:53:18 +0000 | [diff] [blame] | 651 | __armv4_mmu_cache_off: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 652 | mrc p15, 0, r0, c1, c0 |
| 653 | bic r0, r0, #0x000d |
| 654 | mcr p15, 0, r0, c1, c0 @ turn MMU and cache off |
| 655 | mov r0, #0 |
| 656 | mcr p15, 0, r0, c7, c7 @ invalidate whole cache v4 |
| 657 | mcr p15, 0, r0, c8, c7 @ invalidate whole TLB v4 |
| 658 | mov pc, lr |
| 659 | |
Hyok S. Choi | c76b6b4 | 2006-03-24 09:53:18 +0000 | [diff] [blame] | 660 | __arm6_mmu_cache_off: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 661 | mov r0, #0x00000030 @ ARM6 control reg. |
Hyok S. Choi | c76b6b4 | 2006-03-24 09:53:18 +0000 | [diff] [blame] | 662 | b __armv3_mmu_cache_off |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 663 | |
Hyok S. Choi | c76b6b4 | 2006-03-24 09:53:18 +0000 | [diff] [blame] | 664 | __arm7_mmu_cache_off: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 665 | mov r0, #0x00000070 @ ARM7 control reg. |
Hyok S. Choi | c76b6b4 | 2006-03-24 09:53:18 +0000 | [diff] [blame] | 666 | b __armv3_mmu_cache_off |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 667 | |
Hyok S. Choi | c76b6b4 | 2006-03-24 09:53:18 +0000 | [diff] [blame] | 668 | __armv3_mmu_cache_off: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 669 | mcr p15, 0, r0, c1, c0, 0 @ turn MMU and cache off |
| 670 | mov r0, #0 |
| 671 | mcr p15, 0, r0, c7, c0, 0 @ invalidate whole cache v3 |
| 672 | mcr p15, 0, r0, c5, c0, 0 @ invalidate whole TLB v3 |
| 673 | mov pc, lr |
| 674 | |
| 675 | /* |
| 676 | * Clean and flush the cache to maintain consistency. |
| 677 | * |
| 678 | * On entry, |
| 679 | * r6 = processor ID |
| 680 | * On exit, |
| 681 | * r1, r2, r3, r11, r12 corrupted |
| 682 | * This routine must preserve: |
| 683 | * r0, r4, r5, r6, r7 |
| 684 | */ |
| 685 | .align 5 |
| 686 | cache_clean_flush: |
| 687 | mov r3, #16 |
| 688 | b call_cache_fn |
| 689 | |
Hyok S. Choi | 10c2df6 | 2006-03-27 10:21:34 +0100 | [diff] [blame] | 690 | __armv4_mpu_cache_flush: |
| 691 | mov r2, #1 |
| 692 | mov r3, #0 |
| 693 | mcr p15, 0, ip, c7, c6, 0 @ invalidate D cache |
| 694 | mov r1, #7 << 5 @ 8 segments |
| 695 | 1: orr r3, r1, #63 << 26 @ 64 entries |
| 696 | 2: mcr p15, 0, r3, c7, c14, 2 @ clean & invalidate D index |
| 697 | subs r3, r3, #1 << 26 |
| 698 | bcs 2b @ entries 63 to 0 |
| 699 | subs r1, r1, #1 << 5 |
| 700 | bcs 1b @ segments 7 to 0 |
| 701 | |
| 702 | teq r2, #0 |
| 703 | mcrne p15, 0, ip, c7, c5, 0 @ invalidate I cache |
| 704 | mcr p15, 0, ip, c7, c10, 4 @ drain WB |
| 705 | mov pc, lr |
| 706 | |
| 707 | |
Hyok S. Choi | c76b6b4 | 2006-03-24 09:53:18 +0000 | [diff] [blame] | 708 | __armv6_mmu_cache_flush: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 709 | mov r1, #0 |
| 710 | mcr p15, 0, r1, c7, c14, 0 @ clean+invalidate D |
| 711 | mcr p15, 0, r1, c7, c5, 0 @ invalidate I+BTB |
| 712 | mcr p15, 0, r1, c7, c15, 0 @ clean+invalidate unified |
| 713 | mcr p15, 0, r1, c7, c10, 4 @ drain WB |
| 714 | mov pc, lr |
| 715 | |
Hyok S. Choi | c76b6b4 | 2006-03-24 09:53:18 +0000 | [diff] [blame] | 716 | __armv4_mmu_cache_flush: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 717 | mov r2, #64*1024 @ default: 32K dcache size (*2) |
| 718 | mov r11, #32 @ default: 32 byte line size |
| 719 | mrc p15, 0, r3, c0, c0, 1 @ read cache type |
| 720 | teq r3, r6 @ cache ID register present? |
| 721 | beq no_cache_id |
| 722 | mov r1, r3, lsr #18 |
| 723 | and r1, r1, #7 |
| 724 | mov r2, #1024 |
| 725 | mov r2, r2, lsl r1 @ base dcache size *2 |
| 726 | tst r3, #1 << 14 @ test M bit |
| 727 | addne r2, r2, r2, lsr #1 @ +1/2 size if M == 1 |
| 728 | mov r3, r3, lsr #12 |
| 729 | and r3, r3, #3 |
| 730 | mov r11, #8 |
| 731 | mov r11, r11, lsl r3 @ cache line size in bytes |
| 732 | no_cache_id: |
| 733 | bic r1, pc, #63 @ align to longest cache line |
| 734 | add r2, r1, r2 |
| 735 | 1: ldr r3, [r1], r11 @ s/w flush D cache |
| 736 | teq r1, r2 |
| 737 | bne 1b |
| 738 | |
| 739 | mcr p15, 0, r1, c7, c5, 0 @ flush I cache |
| 740 | mcr p15, 0, r1, c7, c6, 0 @ flush D cache |
| 741 | mcr p15, 0, r1, c7, c10, 4 @ drain WB |
| 742 | mov pc, lr |
| 743 | |
Hyok S. Choi | c76b6b4 | 2006-03-24 09:53:18 +0000 | [diff] [blame] | 744 | __armv3_mmu_cache_flush: |
Hyok S. Choi | 10c2df6 | 2006-03-27 10:21:34 +0100 | [diff] [blame] | 745 | __armv3_mpu_cache_flush: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 746 | mov r1, #0 |
| 747 | mcr p15, 0, r0, c7, c0, 0 @ invalidate whole cache v3 |
| 748 | mov pc, lr |
| 749 | |
| 750 | /* |
| 751 | * Various debugging routines for printing hex characters and |
| 752 | * memory, which again must be relocatable. |
| 753 | */ |
| 754 | #ifdef DEBUG |
| 755 | .type phexbuf,#object |
| 756 | phexbuf: .space 12 |
| 757 | .size phexbuf, . - phexbuf |
| 758 | |
| 759 | phex: adr r3, phexbuf |
| 760 | mov r2, #0 |
| 761 | strb r2, [r3, r1] |
| 762 | 1: subs r1, r1, #1 |
| 763 | movmi r0, r3 |
| 764 | bmi puts |
| 765 | and r2, r0, #15 |
| 766 | mov r0, r0, lsr #4 |
| 767 | cmp r2, #10 |
| 768 | addge r2, r2, #7 |
| 769 | add r2, r2, #'0' |
| 770 | strb r2, [r3, r1] |
| 771 | b 1b |
| 772 | |
| 773 | puts: loadsp r3 |
| 774 | 1: ldrb r2, [r0], #1 |
| 775 | teq r2, #0 |
| 776 | moveq pc, lr |
Russell King | 5cd0c34 | 2005-05-03 12:18:46 +0100 | [diff] [blame] | 777 | 2: writeb r2, r3 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 778 | mov r1, #0x00020000 |
| 779 | 3: subs r1, r1, #1 |
| 780 | bne 3b |
| 781 | teq r2, #'\n' |
| 782 | moveq r2, #'\r' |
| 783 | beq 2b |
| 784 | teq r0, #0 |
| 785 | bne 1b |
| 786 | mov pc, lr |
| 787 | putc: |
| 788 | mov r2, r0 |
| 789 | mov r0, #0 |
| 790 | loadsp r3 |
| 791 | b 2b |
| 792 | |
| 793 | memdump: mov r12, r0 |
| 794 | mov r10, lr |
| 795 | mov r11, #0 |
| 796 | 2: mov r0, r11, lsl #2 |
| 797 | add r0, r0, r12 |
| 798 | mov r1, #8 |
| 799 | bl phex |
| 800 | mov r0, #':' |
| 801 | bl putc |
| 802 | 1: mov r0, #' ' |
| 803 | bl putc |
| 804 | ldr r0, [r12, r11, lsl #2] |
| 805 | mov r1, #8 |
| 806 | bl phex |
| 807 | and r0, r11, #7 |
| 808 | teq r0, #3 |
| 809 | moveq r0, #' ' |
| 810 | bleq putc |
| 811 | and r0, r11, #7 |
| 812 | add r11, r11, #1 |
| 813 | teq r0, #7 |
| 814 | bne 1b |
| 815 | mov r0, #'\n' |
| 816 | bl putc |
| 817 | cmp r11, #64 |
| 818 | blt 2b |
| 819 | mov pc, r10 |
| 820 | #endif |
| 821 | |
| 822 | reloc_end: |
| 823 | |
| 824 | .align |
| 825 | .section ".stack", "w" |
| 826 | user_stack: .space 4096 |