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 r12 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 /* Initialize machine status; enable machine check interrupt */
101 /*----------------------------------------------------------------------*/
102 li r3, MSR_KERNEL /* Set FP, ME, RI flags */
104 mtspr SRR1, r3 /* Make SRR1 match MSR */
106 addis r0,0,0x0000 /* lets make sure that r0 is really 0 */
107 mtspr HID0, r0 /* disable I and D caches */
109 mfspr r3, ICR /* clear Interrupt Cause Register */
111 mfmsr r3 /* turn off address translation */
117 sync /* the MMU should be off... */
121 #if defined(CONFIG_BMW)
122 bl early_init_f /* Must be ASM: no stack yet! */
125 * Setup BATs - cannot be done in C since we don't have a stack yet
132 ori r3, r3, (MSR_IR | MSR_DR)
134 #if !defined(CONFIG_BMW)
135 /* Enable and invalidate data cache.
139 ori r3, r3, HID0_DCE | HID0_DCI
146 /* Allocate Initial RAM in data cache.
148 lis r3, CONFIG_SYS_INIT_RAM_ADDR@h
149 ori r3, r3, CONFIG_SYS_INIT_RAM_ADDR@l
157 /* Lock way0 in data cache.
166 #endif /* !CONFIG_BMW */
168 * Thisk the stack pointer *somewhere* sensible. Doesnt
169 * matter much where as we'll move it when we relocate
171 lis r1, (CONFIG_SYS_INIT_RAM_ADDR + CONFIG_SYS_GBL_DATA_OFFSET)@h
172 ori r1, r1, (CONFIG_SYS_INIT_RAM_ADDR + CONFIG_SYS_GBL_DATA_OFFSET)@l
174 li r0, 0 /* Make room for stack frame header and */
175 stwu r0, -4(r1) /* clear final stack frame so that */
176 stwu r0, -4(r1) /* stack backtraces terminate cleanly */
178 /* let the C-code set up the rest */
180 /* Be careful to keep code relocatable ! */
181 /*----------------------------------------------------------------------*/
183 GET_GOT /* initialize GOT access */
186 bl cpu_init_f /* run low-level CPU init code (from Flash) */
188 bl board_init_f /* run 1st part of board init code (from Flash) */
190 /* NOTREACHED - board_init_f() does not return */
193 .globl _start_of_vectors
197 STD_EXCEPTION(EXC_OFF_MACH_CHCK, MachineCheck, MachineCheckException)
199 /* Data Storage exception. "Never" generated on the 860. */
200 STD_EXCEPTION(EXC_OFF_DATA_STOR, DataStorage, UnknownException)
202 /* Instruction Storage exception. "Never" generated on the 860. */
203 STD_EXCEPTION(EXC_OFF_INS_STOR, InstStorage, UnknownException)
205 /* External Interrupt exception. */
206 STD_EXCEPTION(EXC_OFF_EXTERNAL, ExtInterrupt, external_interrupt)
208 /* Alignment exception. */
211 EXCEPTION_PROLOG(SRR0, SRR1)
216 addi r3,r1,STACK_FRAME_OVERHEAD
217 EXC_XFER_TEMPLATE(Alignment, AlignmentException, MSR_KERNEL, COPY_EE)
219 /* Program check exception */
222 EXCEPTION_PROLOG(SRR0, SRR1)
223 addi r3,r1,STACK_FRAME_OVERHEAD
224 EXC_XFER_TEMPLATE(ProgramCheck, ProgramCheckException,
227 /* No FPU on MPC8xx. This exception is not supposed to happen.
229 STD_EXCEPTION(EXC_OFF_FPUNAVAIL, FPUnavailable, UnknownException)
231 /* I guess we could implement decrementer, and may have
232 * to someday for timekeeping.
234 STD_EXCEPTION(EXC_OFF_DECR, Decrementer, timer_interrupt)
235 STD_EXCEPTION(0xa00, Trap_0a, UnknownException)
236 STD_EXCEPTION(0xb00, Trap_0b, UnknownException)
237 STD_EXCEPTION(0xc00, SystemCall, UnknownException)
239 STD_EXCEPTION(EXC_OFF_TRACE, SingleStep, UnknownException)
241 STD_EXCEPTION(EXC_OFF_FPUNASSIST, Trap_0e, UnknownException)
242 STD_EXCEPTION(EXC_OFF_PMI, Trap_0f, UnknownException)
244 STD_EXCEPTION(EXC_OFF_ITME, InstructionTransMiss, UnknownException)
245 STD_EXCEPTION(EXC_OFF_DLTME, DataLoadTransMiss, UnknownException)
246 STD_EXCEPTION(EXC_OFF_DSTME, DataStoreTransMiss, UnknownException)
247 STD_EXCEPTION(EXC_OFF_IABE, InstructionBreakpoint, DebugException)
248 STD_EXCEPTION(EXC_OFF_SMIE, SysManageInt, UnknownException)
249 STD_EXCEPTION(0x1500, Reserved5, UnknownException)
250 STD_EXCEPTION(0x1600, Reserved6, UnknownException)
251 STD_EXCEPTION(0x1700, Reserved7, UnknownException)
252 STD_EXCEPTION(0x1800, Reserved8, UnknownException)
253 STD_EXCEPTION(0x1900, Reserved9, UnknownException)
254 STD_EXCEPTION(0x1a00, ReservedA, UnknownException)
255 STD_EXCEPTION(0x1b00, ReservedB, UnknownException)
256 STD_EXCEPTION(0x1c00, ReservedC, UnknownException)
257 STD_EXCEPTION(0x1d00, ReservedD, UnknownException)
258 STD_EXCEPTION(0x1e00, ReservedE, UnknownException)
259 STD_EXCEPTION(0x1f00, ReservedF, UnknownException)
261 STD_EXCEPTION(EXC_OFF_RMTE, RunModeTrace, UnknownException)
263 .globl _end_of_vectors
270 * This code finishes saving the registers to the exception frame
271 * and jumps to the appropriate handler for the exception.
272 * Register r21 is pointer into trap frame, r1 has new stack pointer.
274 .globl transfer_to_handler
286 mfspr r23,SPRG3 /* if from user, fix up tss.regs */
288 addi r24,r1,STACK_FRAME_OVERHEAD
290 2: addi r2,r23,-TSS /* set r2 to current */
294 andi. r24,r23,0x3f00 /* get vector offset */
298 mtspr SPRG2,r22 /* r1 is now kernel sp */
300 addi r24,r2,TASK_STRUCT_SIZE /* check for kernel stack overflow */
304 bgt stack_ovf /* if r2 < r1 < r2+TASK_STRUCT_SIZE */
306 lwz r24,0(r23) /* virtual address of handler */
307 lwz r23,4(r23) /* where to go when done */
309 ori r20,r20,0x30 /* enable IR, DR */
313 rfi /* jump to handler, enable MMU */
316 mfmsr r28 /* Disable interrupts */
320 SYNC /* Some chip revs need this... */
335 lwz r2,_NIP(r1) /* Restore environment */
349 mfspr r5,HID0 /* turn on the I cache. */
350 ori r5,r5,0x8800 /* Instruction cache only! */
353 and r6,r5,r6 /* clear the invalidate bit */
361 .globl icache_disable
376 srwi r3, r3, 15 /* >>15 & 1=> select bit 16 */
382 mfspr r5,HID0 /* turn on the D cache. */
383 ori r5,r5,0x4400 /* Data cache only! */
384 mfspr r4, PVR /* read PVR */
385 srawi r3, r4, 16 /* shift off the least 16 bits */
386 cmpi 0, 0, r3, 0xC /* Check for Max pvr */
388 ori r5,r5,0x0040 /* setting the DCFA bit, for Max rev 1 errata */
392 and r6,r5,r6 /* clear the invalidate bit */
400 .globl dcache_disable
415 srwi r3, r3, 14 /* >>14 & 1=> select bit 17 */
421 /*TODO : who uses this, what should it do?
432 /*------------------------------------------------------------------------------*/
435 * void relocate_code (addr_sp, gd, addr_moni)
437 * This "function" does not return, instead it continues in RAM
438 * after relocating the monitor code.
442 * r5 = length in bytes
448 mr r1, r3 /* Set new stack pointer */
449 mr r9, r4 /* Save copy of Global Data pointer */
450 mr r10, r5 /* Save copy of Destination Address */
453 mr r3, r5 /* Destination Address */
454 #ifdef CONFIG_SYS_RAMBOOT
455 lis r4, CONFIG_SYS_SDRAM_BASE@h /* Source Address */
456 ori r4, r4, CONFIG_SYS_SDRAM_BASE@l
458 lis r4, CONFIG_SYS_MONITOR_BASE@h /* Source Address */
459 ori r4, r4, CONFIG_SYS_MONITOR_BASE@l
461 lwz r5, GOT(__init_end)
463 li r6, CONFIG_SYS_CACHELINE_SIZE /* Cache Line Size */
468 * New GOT-PTR = (old GOT-PTR - CONFIG_SYS_MONITOR_BASE) + Destination Address
474 /* First our own GOT */
476 /* the the one used by the C code */
486 beq cr1,4f /* In place copy is not necessary */
487 beq 7f /* Protect against 0 count */
506 #if !defined(CONFIG_BMW)
507 /* Unlock the data cache and invalidate locked area */
510 lis r4, CONFIG_SYS_INIT_RAM_ADDR@h
511 ori r4, r4, CONFIG_SYS_INIT_RAM_ADDR@l
521 * Now flush the cache: note that we must start from a cache aligned
522 * address. Otherwise we might miss one cache line.
526 beq 7f /* Always flush prefetch queue in any case */
534 sync /* Wait for all dcbst to complete on bus */
540 7: sync /* Wait for all icbi to complete on bus */
544 * We are done. Do not return, instead branch to second part of board
545 * initialization, now running from RAM.
548 addi r0, r10, in_ram - _start + EXC_OFF_SYS_RESET
555 * Relocation Function, r12 point to got2+0x8000
557 * Adjust got2 pointers, no need to check for 0, this code
558 * already puts a few entries in the table.
560 li r0,__got2_entries@sectoff@l
561 la r3,GOT(_GOT2_TABLE_)
562 lwz r11,GOT(_GOT2_TABLE_)
574 * Now adjust the fixups and the pointers to the fixups
575 * in case we need to move ourselves again.
577 li r0,__fixup_entries@sectoff@l
578 lwz r3,GOT(_FIXUP_TABLE_)
592 * Now clear BSS segment
594 lwz r3,GOT(__bss_start)
608 mr r3, r9 /* Global Data pointer */
609 mr r4, r10 /* Destination Address */
613 * Copy exception vector code to low memory
616 * r7: source address, r8: end address, r9: target address
620 mflr r4 /* save link register */
623 lwz r8, GOT(_end_of_vectors)
625 li r9, 0x100 /* reset vector always at 0x100 */
628 bgelr /* return if r7>=r8 - just in case */
638 * relocate `hdlr' and `int_return' entries
640 li r7, .L_MachineCheck - _start + EXC_OFF_SYS_RESET
641 li r8, Alignment - _start + EXC_OFF_SYS_RESET
644 addi r7, r7, 0x100 /* next exception vector */
648 li r7, .L_Alignment - _start + EXC_OFF_SYS_RESET
651 li r7, .L_ProgramCheck - _start + EXC_OFF_SYS_RESET
654 li r7, .L_FPUnavailable - _start + EXC_OFF_SYS_RESET
655 li r8, SystemCall - _start + EXC_OFF_SYS_RESET
658 addi r7, r7, 0x100 /* next exception vector */
662 li r7, .L_SingleStep - _start + EXC_OFF_SYS_RESET
663 li r8, _end_of_vectors - _start + EXC_OFF_SYS_RESET
666 addi r7, r7, 0x100 /* next exception vector */
670 mtlr r4 /* restore link register */
673 /* Setup the BAT registers.
676 lis r4, CONFIG_SYS_IBAT0L@h
677 ori r4, r4, CONFIG_SYS_IBAT0L@l
678 lis r3, CONFIG_SYS_IBAT0U@h
679 ori r3, r3, CONFIG_SYS_IBAT0U@l
684 lis r4, CONFIG_SYS_DBAT0L@h
685 ori r4, r4, CONFIG_SYS_DBAT0L@l
686 lis r3, CONFIG_SYS_DBAT0U@h
687 ori r3, r3, CONFIG_SYS_DBAT0U@l
692 lis r4, CONFIG_SYS_IBAT1L@h
693 ori r4, r4, CONFIG_SYS_IBAT1L@l
694 lis r3, CONFIG_SYS_IBAT1U@h
695 ori r3, r3, CONFIG_SYS_IBAT1U@l
700 lis r4, CONFIG_SYS_DBAT1L@h
701 ori r4, r4, CONFIG_SYS_DBAT1L@l
702 lis r3, CONFIG_SYS_DBAT1U@h
703 ori r3, r3, CONFIG_SYS_DBAT1U@l
708 lis r4, CONFIG_SYS_IBAT2L@h
709 ori r4, r4, CONFIG_SYS_IBAT2L@l
710 lis r3, CONFIG_SYS_IBAT2U@h
711 ori r3, r3, CONFIG_SYS_IBAT2U@l
716 lis r4, CONFIG_SYS_DBAT2L@h
717 ori r4, r4, CONFIG_SYS_DBAT2L@l
718 lis r3, CONFIG_SYS_DBAT2U@h
719 ori r3, r3, CONFIG_SYS_DBAT2U@l
724 lis r4, CONFIG_SYS_IBAT3L@h
725 ori r4, r4, CONFIG_SYS_IBAT3L@l
726 lis r3, CONFIG_SYS_IBAT3U@h
727 ori r3, r3, CONFIG_SYS_IBAT3U@l
732 lis r4, CONFIG_SYS_DBAT3L@h
733 ori r4, r4, CONFIG_SYS_DBAT3L@l
734 lis r3, CONFIG_SYS_DBAT3U@h
735 ori r3, r3, CONFIG_SYS_DBAT3U@l
741 * -> for (val = 0; val < 0x20000; val+=0x1000)