2 * Copyright (C) 1998 Dan Malek <dmalek@jlc.net>
3 * Copyright (C) 1999 Magnus Damm <kieraypc01.p.y.kie.era.ericsson.se>
4 * Copyright (C) 2000,2001,2002 Wolfgang Denk <wd@denx.de>
6 * See file CREDITS for list of people who contributed to this
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License as
11 * published by the Free Software Foundation; either version 2 of
12 * the License, or (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
25 /* U-Boot - Startup Code for PowerPC based Embedded Boards
28 * The processor starts at 0x00000100 and the code is executed
29 * from flash. The code is organized to be at an other address
30 * in memory, but as long we don't jump around before relocating.
31 * board_init lies at a quite high address and when the cpu has
32 * jumped there, everything is ok.
33 * This works because the cpu gives the FLASH (CS0) the whole
34 * address space at startup, and board_init lies as a echo of
35 * the flash somewhere up there in the memorymap.
37 * board_init will change CS0 to be positioned at the correct
38 * address and (s)dram will be positioned at address 0
42 #include <timestamp.h>
45 #define _LINUX_CONFIG_H 1 /* avoid reading Linux autoconf.h file */
47 #include <ppc_asm.tmpl>
50 #include <asm/cache.h>
53 #ifndef CONFIG_IDENT_STRING
54 #define CONFIG_IDENT_STRING ""
57 /* We don't want the MMU yet.
60 /* FP, Machine Check and Recoverable Interr. */
61 #define MSR_KERNEL ( MSR_FP | MSR_ME | MSR_RI )
64 * Set up GOT: Global Offset Table
66 * Use r14 to access the GOT
69 GOT_ENTRY(_GOT2_TABLE_)
70 GOT_ENTRY(_FIXUP_TABLE_)
73 GOT_ENTRY(_start_of_vectors)
74 GOT_ENTRY(_end_of_vectors)
75 GOT_ENTRY(transfer_to_handler)
79 GOT_ENTRY(__bss_start)
80 #if defined(CONFIG_FADS)
81 GOT_ENTRY(environment)
86 * r3 - 1st arg to board_init(): IMMP pointer
87 * r4 - 2nd arg to board_init(): boot flag
90 .long 0x27051956 /* U-Boot Magic Number */
94 .ascii " (", U_BOOT_DATE, " - ", U_BOOT_TIME, ")"
95 .ascii CONFIG_IDENT_STRING, "\0"
100 li r21, BOOTFLAG_COLD /* Normal Power-On: Boot from FLASH */
103 . = EXC_OFF_SYS_RESET + 0x10
107 li r21, BOOTFLAG_WARM /* Software reboot */
113 /* Initialize machine status; enable machine check interrupt */
114 /*----------------------------------------------------------------------*/
115 li r3, MSR_KERNEL /* Set FP, ME, RI flags */
117 mtspr SRR1, r3 /* Make SRR1 match MSR */
119 addis r0,0,0x0000 /* lets make sure that r0 is really 0 */
120 mtspr HID0, r0 /* disable I and D caches */
122 mfspr r3, ICR /* clear Interrupt Cause Register */
124 mfmsr r3 /* turn off address translation */
130 sync /* the MMU should be off... */
134 #if defined(CONFIG_BMW)
135 bl early_init_f /* Must be ASM: no stack yet! */
138 * Setup BATs - cannot be done in C since we don't have a stack yet
145 ori r3, r3, (MSR_IR | MSR_DR)
147 #if !defined(CONFIG_BMW)
148 /* Enable and invalidate data cache.
152 ori r3, r3, HID0_DCE | HID0_DCI
159 /* Allocate Initial RAM in data cache.
161 lis r3, CONFIG_SYS_INIT_RAM_ADDR@h
162 ori r3, r3, CONFIG_SYS_INIT_RAM_ADDR@l
170 /* Lock way0 in data cache.
179 #endif /* !CONFIG_BMW */
181 * Thisk the stack pointer *somewhere* sensible. Doesnt
182 * matter much where as we'll move it when we relocate
184 lis r1, (CONFIG_SYS_INIT_RAM_ADDR + CONFIG_SYS_GBL_DATA_OFFSET)@h
185 ori r1, r1, (CONFIG_SYS_INIT_RAM_ADDR + CONFIG_SYS_GBL_DATA_OFFSET)@l
187 li r0, 0 /* Make room for stack frame header and */
188 stwu r0, -4(r1) /* clear final stack frame so that */
189 stwu r0, -4(r1) /* stack backtraces terminate cleanly */
191 /* let the C-code set up the rest */
193 /* Be careful to keep code relocatable ! */
194 /*----------------------------------------------------------------------*/
196 GET_GOT /* initialize GOT access */
199 bl cpu_init_f /* run low-level CPU init code (from Flash) */
203 bl board_init_f /* run 1st part of board init code (from Flash) */
206 .globl _start_of_vectors
210 STD_EXCEPTION(EXC_OFF_MACH_CHCK, MachineCheck, MachineCheckException)
212 /* Data Storage exception. "Never" generated on the 860. */
213 STD_EXCEPTION(EXC_OFF_DATA_STOR, DataStorage, UnknownException)
215 /* Instruction Storage exception. "Never" generated on the 860. */
216 STD_EXCEPTION(EXC_OFF_INS_STOR, InstStorage, UnknownException)
218 /* External Interrupt exception. */
219 STD_EXCEPTION(EXC_OFF_EXTERNAL, ExtInterrupt, external_interrupt)
221 /* Alignment exception. */
224 EXCEPTION_PROLOG(SRR0, SRR1)
229 addi r3,r1,STACK_FRAME_OVERHEAD
231 rlwimi r20,r23,0,16,16 /* copy EE bit from saved MSR */
232 lwz r6,GOT(transfer_to_handler)
236 .long AlignmentException - _start + EXC_OFF_SYS_RESET
237 .long int_return - _start + EXC_OFF_SYS_RESET
239 /* Program check exception */
242 EXCEPTION_PROLOG(SRR0, SRR1)
243 addi r3,r1,STACK_FRAME_OVERHEAD
245 rlwimi r20,r23,0,16,16 /* copy EE bit from saved MSR */
246 lwz r6,GOT(transfer_to_handler)
250 .long ProgramCheckException - _start + EXC_OFF_SYS_RESET
251 .long int_return - _start + EXC_OFF_SYS_RESET
253 /* No FPU on MPC8xx. This exception is not supposed to happen.
255 STD_EXCEPTION(EXC_OFF_FPUNAVAIL, FPUnavailable, UnknownException)
257 /* I guess we could implement decrementer, and may have
258 * to someday for timekeeping.
260 STD_EXCEPTION(EXC_OFF_DECR, Decrementer, timer_interrupt)
261 STD_EXCEPTION(0xa00, Trap_0a, UnknownException)
262 STD_EXCEPTION(0xb00, Trap_0b, UnknownException)
263 STD_EXCEPTION(0xc00, SystemCall, UnknownException)
265 STD_EXCEPTION(EXC_OFF_TRACE, SingleStep, UnknownException)
267 STD_EXCEPTION(EXC_OFF_FPUNASSIST, Trap_0e, UnknownException)
268 STD_EXCEPTION(EXC_OFF_PMI, Trap_0f, UnknownException)
270 STD_EXCEPTION(EXC_OFF_ITME, InstructionTransMiss, UnknownException)
271 STD_EXCEPTION(EXC_OFF_DLTME, DataLoadTransMiss, UnknownException)
272 STD_EXCEPTION(EXC_OFF_DSTME, DataStoreTransMiss, UnknownException)
273 STD_EXCEPTION(EXC_OFF_IABE, InstructionBreakpoint, DebugException)
274 STD_EXCEPTION(EXC_OFF_SMIE, SysManageInt, UnknownException)
275 STD_EXCEPTION(0x1500, Reserved5, UnknownException)
276 STD_EXCEPTION(0x1600, Reserved6, UnknownException)
277 STD_EXCEPTION(0x1700, Reserved7, UnknownException)
278 STD_EXCEPTION(0x1800, Reserved8, UnknownException)
279 STD_EXCEPTION(0x1900, Reserved9, UnknownException)
280 STD_EXCEPTION(0x1a00, ReservedA, UnknownException)
281 STD_EXCEPTION(0x1b00, ReservedB, UnknownException)
282 STD_EXCEPTION(0x1c00, ReservedC, UnknownException)
283 STD_EXCEPTION(0x1d00, ReservedD, UnknownException)
284 STD_EXCEPTION(0x1e00, ReservedE, UnknownException)
285 STD_EXCEPTION(0x1f00, ReservedF, UnknownException)
287 STD_EXCEPTION(EXC_OFF_RMTE, RunModeTrace, UnknownException)
289 .globl _end_of_vectors
296 * This code finishes saving the registers to the exception frame
297 * and jumps to the appropriate handler for the exception.
298 * Register r21 is pointer into trap frame, r1 has new stack pointer.
300 .globl transfer_to_handler
312 mfspr r23,SPRG3 /* if from user, fix up tss.regs */
314 addi r24,r1,STACK_FRAME_OVERHEAD
316 2: addi r2,r23,-TSS /* set r2 to current */
320 andi. r24,r23,0x3f00 /* get vector offset */
324 mtspr SPRG2,r22 /* r1 is now kernel sp */
326 addi r24,r2,TASK_STRUCT_SIZE /* check for kernel stack overflow */
330 bgt stack_ovf /* if r2 < r1 < r2+TASK_STRUCT_SIZE */
332 lwz r24,0(r23) /* virtual address of handler */
333 lwz r23,4(r23) /* where to go when done */
335 ori r20,r20,0x30 /* enable IR, DR */
339 rfi /* jump to handler, enable MMU */
342 mfmsr r28 /* Disable interrupts */
346 SYNC /* Some chip revs need this... */
361 lwz r2,_NIP(r1) /* Restore environment */
375 mfspr r5,HID0 /* turn on the I cache. */
376 ori r5,r5,0x8800 /* Instruction cache only! */
379 and r6,r5,r6 /* clear the invalidate bit */
387 .globl icache_disable
402 srwi r3, r3, 15 /* >>15 & 1=> select bit 16 */
408 mfspr r5,HID0 /* turn on the D cache. */
409 ori r5,r5,0x4400 /* Data cache only! */
410 mfspr r4, PVR /* read PVR */
411 srawi r3, r4, 16 /* shift off the least 16 bits */
412 cmpi 0, 0, r3, 0xC /* Check for Max pvr */
414 ori r5,r5,0x0040 /* setting the DCFA bit, for Max rev 1 errata */
418 and r6,r5,r6 /* clear the invalidate bit */
426 .globl dcache_disable
441 srwi r3, r3, 14 /* >>14 & 1=> select bit 17 */
447 /*TODO : who uses this, what should it do?
458 /*------------------------------------------------------------------------------*/
461 * void relocate_code (addr_sp, gd, addr_moni)
463 * This "function" does not return, instead it continues in RAM
464 * after relocating the monitor code.
468 * r5 = length in bytes
474 mr r1, r3 /* Set new stack pointer */
475 mr r9, r4 /* Save copy of Global Data pointer */
476 mr r10, r5 /* Save copy of Destination Address */
478 mr r3, r5 /* Destination Address */
479 #ifdef CONFIG_SYS_RAMBOOT
480 lis r4, CONFIG_SYS_SDRAM_BASE@h /* Source Address */
481 ori r4, r4, CONFIG_SYS_SDRAM_BASE@l
483 lis r4, CONFIG_SYS_MONITOR_BASE@h /* Source Address */
484 ori r4, r4, CONFIG_SYS_MONITOR_BASE@l
486 lwz r5, GOT(__init_end)
488 li r6, CONFIG_SYS_CACHELINE_SIZE /* Cache Line Size */
493 * New GOT-PTR = (old GOT-PTR - CONFIG_SYS_MONITOR_BASE) + Destination Address
499 /* First our own GOT */
501 /* the the one used by the C code */
511 beq cr1,4f /* In place copy is not necessary */
512 beq 7f /* Protect against 0 count */
531 #if !defined(CONFIG_BMW)
532 /* Unlock the data cache and invalidate locked area */
535 lis r4, CONFIG_SYS_INIT_RAM_ADDR@h
536 ori r4, r4, CONFIG_SYS_INIT_RAM_ADDR@l
546 * Now flush the cache: note that we must start from a cache aligned
547 * address. Otherwise we might miss one cache line.
551 beq 7f /* Always flush prefetch queue in any case */
559 sync /* Wait for all dcbst to complete on bus */
565 7: sync /* Wait for all icbi to complete on bus */
569 * We are done. Do not return, instead branch to second part of board
570 * initialization, now running from RAM.
573 addi r0, r10, in_ram - _start + EXC_OFF_SYS_RESET
580 * Relocation Function, r14 point to got2+0x8000
582 * Adjust got2 pointers, no need to check for 0, this code
583 * already puts a few entries in the table.
585 li r0,__got2_entries@sectoff@l
586 la r3,GOT(_GOT2_TABLE_)
587 lwz r11,GOT(_GOT2_TABLE_)
597 * Now adjust the fixups and the pointers to the fixups
598 * in case we need to move ourselves again.
600 2: li r0,__fixup_entries@sectoff@l
601 lwz r3,GOT(_FIXUP_TABLE_)
615 * Now clear BSS segment
617 lwz r3,GOT(__bss_start)
631 mr r3, r9 /* Global Data pointer */
632 mr r4, r10 /* Destination Address */
636 * Copy exception vector code to low memory
639 * r7: source address, r8: end address, r9: target address
644 lwz r8, GOT(_end_of_vectors)
646 li r9, 0x100 /* reset vector always at 0x100 */
649 bgelr /* return if r7>=r8 - just in case */
651 mflr r4 /* save link register */
661 * relocate `hdlr' and `int_return' entries
663 li r7, .L_MachineCheck - _start + EXC_OFF_SYS_RESET
664 li r8, Alignment - _start + EXC_OFF_SYS_RESET
667 addi r7, r7, 0x100 /* next exception vector */
671 li r7, .L_Alignment - _start + EXC_OFF_SYS_RESET
674 li r7, .L_ProgramCheck - _start + EXC_OFF_SYS_RESET
677 li r7, .L_FPUnavailable - _start + EXC_OFF_SYS_RESET
678 li r8, SystemCall - _start + EXC_OFF_SYS_RESET
681 addi r7, r7, 0x100 /* next exception vector */
685 li r7, .L_SingleStep - _start + EXC_OFF_SYS_RESET
686 li r8, _end_of_vectors - _start + EXC_OFF_SYS_RESET
689 addi r7, r7, 0x100 /* next exception vector */
693 mtlr r4 /* restore link register */
697 * Function: relocate entries for one exception vector
700 lwz r0, 0(r7) /* hdlr ... */
701 add r0, r0, r3 /* ... += dest_addr */
704 lwz r0, 4(r7) /* int_return ... */
705 add r0, r0, r3 /* ... += dest_addr */
710 /* Setup the BAT registers.
713 lis r4, CONFIG_SYS_IBAT0L@h
714 ori r4, r4, CONFIG_SYS_IBAT0L@l
715 lis r3, CONFIG_SYS_IBAT0U@h
716 ori r3, r3, CONFIG_SYS_IBAT0U@l
721 lis r4, CONFIG_SYS_DBAT0L@h
722 ori r4, r4, CONFIG_SYS_DBAT0L@l
723 lis r3, CONFIG_SYS_DBAT0U@h
724 ori r3, r3, CONFIG_SYS_DBAT0U@l
729 lis r4, CONFIG_SYS_IBAT1L@h
730 ori r4, r4, CONFIG_SYS_IBAT1L@l
731 lis r3, CONFIG_SYS_IBAT1U@h
732 ori r3, r3, CONFIG_SYS_IBAT1U@l
737 lis r4, CONFIG_SYS_DBAT1L@h
738 ori r4, r4, CONFIG_SYS_DBAT1L@l
739 lis r3, CONFIG_SYS_DBAT1U@h
740 ori r3, r3, CONFIG_SYS_DBAT1U@l
745 lis r4, CONFIG_SYS_IBAT2L@h
746 ori r4, r4, CONFIG_SYS_IBAT2L@l
747 lis r3, CONFIG_SYS_IBAT2U@h
748 ori r3, r3, CONFIG_SYS_IBAT2U@l
753 lis r4, CONFIG_SYS_DBAT2L@h
754 ori r4, r4, CONFIG_SYS_DBAT2L@l
755 lis r3, CONFIG_SYS_DBAT2U@h
756 ori r3, r3, CONFIG_SYS_DBAT2U@l
761 lis r4, CONFIG_SYS_IBAT3L@h
762 ori r4, r4, CONFIG_SYS_IBAT3L@l
763 lis r3, CONFIG_SYS_IBAT3U@h
764 ori r3, r3, CONFIG_SYS_IBAT3U@l
769 lis r4, CONFIG_SYS_DBAT3L@h
770 ori r4, r4, CONFIG_SYS_DBAT3L@l
771 lis r3, CONFIG_SYS_DBAT3U@h
772 ori r3, r3, CONFIG_SYS_DBAT3U@l
778 * -> for (val = 0; val < 0x20000; val+=0x1000)