[coreboot] Patch set updated for coreboot: a287e0f armv7: begin splitting old start.S apart
David Hendricks (dhendrix@chromium.org)
gerrit at coreboot.org
Fri Dec 28 02:22:47 CET 2012
David Hendricks (dhendrix at chromium.org) just uploaded a new patch set to gerrit, which you can find at http://review.coreboot.org/2083
-gerrit
commit a287e0fc53028c4826c086e1148ed7e09c3d1d82
Author: David Hendricks <dhendrix at chromium.org>
Date: Thu Dec 27 15:23:57 2012 -0800
armv7: begin splitting old start.S apart
The old start.S file did a lot of work and had a few ugly #ifndef's.
This init.S file will eventually contain only bare minimum, generic
ARM code. Processor-specific stuff and things that take place later
in the boot process should go elsewhere.
Change-Id: I7db0a77ee4bbad1ddecb193ea125d8941a50532b
Signed-off-by: David Hendricks <dhendrix at chromium.org>
---
src/arch/armv7/Makefile.inc | 4 +-
src/arch/armv7/init/init.S | 561 ++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 562 insertions(+), 3 deletions(-)
diff --git a/src/arch/armv7/Makefile.inc b/src/arch/armv7/Makefile.inc
index b413d3e..1a1271f 100644
--- a/src/arch/armv7/Makefile.inc
+++ b/src/arch/armv7/Makefile.inc
@@ -142,9 +142,7 @@ endif
CFLAGS += -D__KERNEL__
CFLAGS += -D__LINUX_ARM_ARCH__=7
-# FIXME(dhendrix): trying to split start.S apart...
-crt0s = $(src)/arch/armv7/start.S
-#crt0s = $(src)/arch/armv7/romstage.S
+crt0s = $(src)/arch/armv7/init/init.S
ldscripts =
ldscripts += $(src)/arch/armv7/romstage.ld
diff --git a/src/arch/armv7/init/init.S b/src/arch/armv7/init/init.S
new file mode 100644
index 0000000..72adfdc
--- /dev/null
+++ b/src/arch/armv7/init/init.S
@@ -0,0 +1,561 @@
+/*
+ * armboot - Startup Code for OMAP3530/ARM Cortex CPU-core
+ *
+ * Copyright (c) 2004 Texas Instruments <r-woodruff2 at ti.com>
+ *
+ * Copyright (c) 2001 Marius Gröger <mag at sysgo.de>
+ * Copyright (c) 2002 Alex Züpke <azu at sysgo.de>
+ * Copyright (c) 2002 Gary Jennejohn <garyj at denx.de>
+ * Copyright (c) 2003 Richard Woodruff <r-woodruff2 at ti.com>
+ * Copyright (c) 2003 Kshitij <kshitij at ti.com>
+ * Copyright (c) 2006-2008 Syed Mohammed Khasim <x0khasim at ti.com>
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#define __ASSEMBLY__
+#include <system.h>
+
+.globl _start
+_start: b reset
+ ldr pc, _undefined_instruction
+ ldr pc, _software_interrupt
+ ldr pc, _prefetch_abort
+ ldr pc, _data_abort
+ ldr pc, _not_used
+ ldr pc, _irq
+ ldr pc, _fiq
+_undefined_instruction: .word _undefined_instruction
+_software_interrupt: .word _software_interrupt
+_prefetch_abort: .word _prefetch_abort
+_data_abort: .word _data_abort
+_not_used: .word _not_used
+_irq: .word _irq
+_fiq: .word _fiq
+_pad: .word 0x12345678 /* now 16*4=64 */
+
+.global _end_vect
+_end_vect:
+
+ .balignl 16,0xdeadbeef
+/*************************************************************************
+ *
+ * Startup Code (reset vector)
+ *
+ * do important init only if we don't start from memory!
+ * setup Memory and board specific bits prior to relocation.
+ * relocate armboot to ram
+ * setup stack
+ *
+ *************************************************************************/
+
+.globl _TEXT_BASE
+_TEXT_BASE:
+ .word CONFIG_SYS_TEXT_BASE
+
+/*
+ * These are defined in the board-specific linker script.
+ */
+.globl _bss_start_ofs
+_bss_start_ofs:
+ .word _bss - _start
+
+.global _image_copy_end_ofs
+_image_copy_end_ofs:
+ .word __image_copy_end - _start
+
+.globl _bss_end_ofs
+_bss_end_ofs:
+ .word _ebss - _start
+# .word __bss_end__ - _start
+
+.globl _end_ofs
+_end_ofs:
+ .word _end - _start
+
+#ifdef CONFIG_USE_IRQ
+/* IRQ stack memory (calculated at run-time) */
+.globl IRQ_STACK_START
+IRQ_STACK_START:
+ .word 0x0badc0de
+
+/* IRQ stack memory (calculated at run-time) */
+.globl FIQ_STACK_START
+FIQ_STACK_START:
+ .word 0x0badc0de
+#endif
+
+/* IRQ stack memory (calculated at run-time) + 8 bytes */
+.globl IRQ_STACK_START_IN
+IRQ_STACK_START_IN:
+ .word 0x0badc0de
+
+/*
+ * the actual reset code
+ */
+
+reset:
+ /*
+ * set the cpu to SVC32 mode
+ */
+ mrs r0, cpsr
+ bic r0, r0, #0x1f
+ orr r0, r0, #0xd3
+ msr cpsr,r0
+
+ /*
+ * From Cortex-A Series Programmer's Guide:
+ * Only CPU 0 performs initialization. Other CPUs go into WFI
+ * to do this, first work out which CPU this is
+ * this code typically is run before any other initialization step
+ */
+ mrc p15, 0, r1, c0, c0, 5 @ Read Multiprocessor Affinity Register
+ and r1, r1, #0x3 @ Extract CPU ID bits
+ cmp r1, #0
+ /* FIXME(dhendrix): this should be WFI or something */
+ bne infinite_loop @ Loop if not core0
+
+ /* Set V=0 in CP15 SCTRL register - for VBAR to point to vector */
+ mrc p15, 0, r0, c1, c0, 0 @ Read CP15 SCTRL Register
+ bic r0, #CR_V @ V = 0
+ mcr p15, 0, r0, c1, c0, 0 @ Write CP15 SCTRL Register
+
+ /* Set vector address in CP15 VBAR register */
+ ldr r0, =_start
+ mcr p15, 0, r0, c12, c0, 0 @Set VBAR
+
+ /* the mask ROM code should have PLL and others stable */
+ /*
+ * FIXME(dhendrix): Do we need to explicitly disable icache/dcache
+ * first? See example 15-3 in Cortex-A programmers guide...
+ */
+#if 0
+ bl cpu_init_cp15
+ /* FIXME(dhendrix): this function essentially sets the stack
+ * pointer again, so let's skip it and only set SP in
+ * call_board_init_f below.
+ */
+ bl cpu_init_crit
+#endif
+
+/* Set stackpointer in internal RAM to call board_init_f */
+call_board_init_f:
+ /*
+ * FIXME(dhendrix): The ldr instruction below made some really weird
+ * looking assembly... Ron and I replaced it with the mov{w,t} to
+ * setup the stack pointer and things look better.
+ *
+ * (hungte) I think "movw/movt/mov" makes it even weird, and may put
+ * extra assumption to system architecture? My vote for ldr :)
+ */
+/* ldr sp, =(CONFIG_SYS_INIT_SP_ADDR) */
+ movw r0, #0xF800
+ movt r0, 0x0204
+ mov sp, r0
+ bic sp, sp, #7 /* 8-byte alignment for ABI compliance */
+ ldr r0,=0x00000000
+ bl board_init_f
+
+set_ps_hold:
+ movw r3, #13068
+ movt r3, 4100
+ movw r2, #13068
+ movt r2, 4100
+ ldr r2, [r2, #0]
+ orr r2, r2, #256
+ str r2, [r3, #0]
+ mov pc, lr @ back to my caller
+
+infinite_loop:
+ b infinite_loop
+
+
+/*------------------------------------------------------------------------------*/
+
+/*
+ * void relocate_code (addr_sp, gd, addr_moni)
+ *
+ * This "function" does not return, instead it continues in RAM
+ * after relocating the monitor code.
+ *
+ */
+ .globl relocate_code
+relocate_code:
+ mov r4, r0 /* save addr_sp */
+ mov r5, r1 /* save addr of gd */
+ mov r6, r2 /* save addr of destination */
+
+ /* Set up the stack */
+stack_setup:
+ mov sp, r4
+
+ adr r0, _start
+ subs r9, r6, r0 /* r9 <- relocation offset */
+ beq clear_bss /* skip relocation */
+ mov r1, r6 /* r1 <- scratch for copy_loop */
+ ldr r3, _image_copy_end_ofs
+ add r2, r0, r3 /* r2 <- source end address */
+
+copy_loop:
+ ldmia r0!, {r9-r10} /* copy from source address [r0] */
+ stmia r1!, {r9-r10} /* copy to target address [r1] */
+ cmp r0, r2 /* until source end address [r2] */
+ blo copy_loop
+
+#ifndef CONFIG_SPL_BUILD
+ /*
+ * fix .rel.dyn relocations
+ */
+ ldr r0, _TEXT_BASE /* r0 <- Text base */
+ sub r9, r6, r0 /* r9 <- relocation offset */
+ ldr r10, _dynsym_start_ofs /* r10 <- sym table ofs */
+ add r10, r10, r0 /* r10 <- sym table in FLASH */
+ ldr r2, _rel_dyn_start_ofs /* r2 <- rel dyn start ofs */
+ add r2, r2, r0 /* r2 <- rel dyn start in FLASH */
+ ldr r3, _rel_dyn_end_ofs /* r3 <- rel dyn end ofs */
+ add r3, r3, r0 /* r3 <- rel dyn end in FLASH */
+fixloop:
+ ldr r0, [r2] /* r0 <- location to fix up, IN FLASH! */
+ add r0, r0, r9 /* r0 <- location to fix up in RAM */
+ ldr r1, [r2, #4]
+ and r7, r1, #0xff
+ cmp r7, #23 /* relative fixup? */
+ beq fixrel
+ cmp r7, #2 /* absolute fixup? */
+ beq fixabs
+ /* ignore unknown type of fixup */
+ b fixnext
+fixabs:
+ /* absolute fix: set location to (offset) symbol value */
+ mov r1, r1, LSR #4 /* r1 <- symbol index in .dynsym */
+ add r1, r10, r1 /* r1 <- address of symbol in table */
+ ldr r1, [r1, #4] /* r1 <- symbol value */
+ add r1, r1, r9 /* r1 <- relocated sym addr */
+ b fixnext
+fixrel:
+ /* relative fix: increase location by offset */
+ ldr r1, [r0]
+ add r1, r1, r9
+fixnext:
+ str r1, [r0]
+ add r2, r2, #8 /* each rel.dyn entry is 8 bytes */
+ cmp r2, r3
+ blo fixloop
+ b clear_bss
+_rel_dyn_start_ofs:
+ .word __rel_dyn_start - _start
+_rel_dyn_end_ofs:
+ .word __rel_dyn_end - _start
+_dynsym_start_ofs:
+ .word __dynsym_start - _start
+
+#endif /* #ifndef CONFIG_SPL_BUILD */
+
+clear_bss:
+#ifdef CONFIG_SPL_BUILD
+ /* No relocation for SPL */
+ ldr r0, =_bss
+ ldr r1, =_ebss
+#else
+ ldr r0, _bss_start_ofs
+ ldr r1, _bss_end_ofs
+ mov r4, r6 /* reloc addr */
+ add r0, r0, r4
+ add r1, r1, r4
+#endif
+ mov r2, #0x00000000 /* clear */
+
+clbss_l:str r2, [r0] /* clear loop... */
+ add r0, r0, #4
+ cmp r0, r1
+ bne clbss_l
+
+/*
+ * We are done. Do not return, instead branch to second part of board
+ * initialization, now running from RAM.
+ */
+jump_2_ram:
+/*
+ * If I-cache is enabled invalidate it
+ */
+#ifndef CONFIG_SYS_ICACHE_OFF
+ mcr p15, 0, r0, c7, c5, 0 @ invalidate icache
+ mcr p15, 0, r0, c7, c10, 4 @ DSB
+ mcr p15, 0, r0, c7, c5, 4 @ ISB
+#endif
+ ldr r0, _board_init_r_ofs
+ adr r1, _start
+ add lr, r0, r1
+ add lr, lr, r9
+ /* setup parameters for board_init_r */
+ mov r0, r5 /* gd_t */
+ mov r1, r6 /* dest_addr */
+ /* jump to it ... */
+ mov pc, lr
+
+_board_init_r_ofs:
+ .word board_init_r - _start
+
+/*************************************************************************
+ *
+ * cpu_init_cp15
+ *
+ * Setup CP15 registers (cache, MMU, TLBs). The I-cache is turned on unless
+ * CONFIG_SYS_ICACHE_OFF is defined.
+ *
+ *************************************************************************/
+.globl cpu_init_cp15
+cpu_init_cp15:
+ /*
+ * Invalidate L1 I/D
+ */
+ mov r0, #0 @ set up for MCR
+ mcr p15, 0, r0, c8, c7, 0 @ invalidate TLBs
+ mcr p15, 0, r0, c7, c5, 0 @ invalidate icache
+ mcr p15, 0, r0, c7, c5, 6 @ invalidate BP array
+ mcr p15, 0, r0, c7, c10, 4 @ DSB
+ mcr p15, 0, r0, c7, c5, 4 @ ISB
+
+ /*
+ * disable MMU stuff and caches
+ */
+ mrc p15, 0, r0, c1, c0, 0
+ bic r0, r0, #0x00002000 @ clear bits 13 (--V-)
+ bic r0, r0, #0x00000007 @ clear bits 2:0 (-CAM)
+ orr r0, r0, #0x00000002 @ set bit 1 (--A-) Align
+ orr r0, r0, #0x00000800 @ set bit 11 (Z---) BTB
+#ifdef CONFIG_SYS_ICACHE_OFF
+ bic r0, r0, #0x00001000 @ clear bit 12 (I) I-cache
+#else
+ orr r0, r0, #0x00001000 @ set bit 12 (I) I-cache
+#endif
+ mcr p15, 0, r0, c1, c0, 0
+ mov pc, lr @ back to my caller
+
+
+/*************************************************************************
+ *
+ * CPU_init_critical registers
+ *
+ * setup important registers
+ * setup memory timing
+ *
+ *************************************************************************/
+cpu_init_crit:
+ /*
+ * Jump to board specific initialization...
+ * The Mask ROM will have already initialized
+ * basic memory. Go here to bump up clock rate and handle
+ * wake up conditions.
+ */
+ mov ip, lr @ persevere link reg across call
+ bl lowlevel_init @ go setup pll,mux,memory
+ mov lr, ip @ restore link
+ mov pc, lr @ back to my caller
+
+#ifndef CONFIG_SPL_BUILD
+/*
+ *************************************************************************
+ *
+ * Interrupt handling
+ *
+ *************************************************************************
+ */
+@
+@ IRQ stack frame.
+@
+#define S_FRAME_SIZE 72
+
+#define S_OLD_R0 68
+#define S_PSR 64
+#define S_PC 60
+#define S_LR 56
+#define S_SP 52
+
+#define S_IP 48
+#define S_FP 44
+#define S_R10 40
+#define S_R9 36
+#define S_R8 32
+#define S_R7 28
+#define S_R6 24
+#define S_R5 20
+#define S_R4 16
+#define S_R3 12
+#define S_R2 8
+#define S_R1 4
+#define S_R0 0
+
+#define MODE_SVC 0x13
+#define I_BIT 0x80
+
+/*
+ * use bad_save_user_regs for abort/prefetch/undef/swi ...
+ * use irq_save_user_regs / irq_restore_user_regs for IRQ/FIQ handling
+ */
+
+ .macro bad_save_user_regs
+ sub sp, sp, #S_FRAME_SIZE @ carve out a frame on current
+ @ user stack
+ stmia sp, {r0 - r12} @ Save user registers (now in
+ @ svc mode) r0-r12
+ ldr r2, IRQ_STACK_START_IN @ set base 2 words into abort
+ @ stack
+ ldmia r2, {r2 - r3} @ get values for "aborted" pc
+ @ and cpsr (into parm regs)
+ add r0, sp, #S_FRAME_SIZE @ grab pointer to old stack
+
+ add r5, sp, #S_SP
+ mov r1, lr
+ stmia r5, {r0 - r3} @ save sp_SVC, lr_SVC, pc, cpsr
+ mov r0, sp @ save current stack into r0
+ @ (param register)
+ .endm
+
+ .macro irq_save_user_regs
+ sub sp, sp, #S_FRAME_SIZE
+ stmia sp, {r0 - r12} @ Calling r0-r12
+ add r8, sp, #S_PC @ !! R8 NEEDS to be saved !!
+ @ a reserved stack spot would
+ @ be good.
+ stmdb r8, {sp, lr}^ @ Calling SP, LR
+ str lr, [r8, #0] @ Save calling PC
+ mrs r6, spsr
+ str r6, [r8, #4] @ Save CPSR
+ str r0, [r8, #8] @ Save OLD_R0
+ mov r0, sp
+ .endm
+
+ .macro irq_restore_user_regs
+ ldmia sp, {r0 - lr}^ @ Calling r0 - lr
+ mov r0, r0
+ ldr lr, [sp, #S_PC] @ Get PC
+ add sp, sp, #S_FRAME_SIZE
+ subs pc, lr, #4 @ return & move spsr_svc into
+ @ cpsr
+ .endm
+
+ .macro get_bad_stack
+ ldr r13, IRQ_STACK_START_IN @ setup our mode stack (enter
+ @ in banked mode)
+
+ str lr, [r13] @ save caller lr in position 0
+ @ of saved stack
+ mrs lr, spsr @ get the spsr
+ str lr, [r13, #4] @ save spsr in position 1 of
+ @ saved stack
+
+ mov r13, #MODE_SVC @ prepare SVC-Mode
+ @ msr spsr_c, r13
+ msr spsr, r13 @ switch modes, make sure
+ @ moves will execute
+ mov lr, pc @ capture return pc
+ movs pc, lr @ jump to next instruction &
+ @ switch modes.
+ .endm
+
+ .macro get_bad_stack_swi
+ sub r13, r13, #4 @ space on current stack for
+ @ scratch reg.
+ str r0, [r13] @ save R0's value.
+ ldr r0, IRQ_STACK_START_IN @ get data regions start
+ @ spots for abort stack
+ str lr, [r0] @ save caller lr in position 0
+ @ of saved stack
+ mrs r0, spsr @ get the spsr
+ str lr, [r0, #4] @ save spsr in position 1 of
+ @ saved stack
+ ldr r0, [r13] @ restore r0
+ add r13, r13, #4 @ pop stack entry
+ .endm
+
+ .macro get_irq_stack @ setup IRQ stack
+ ldr sp, IRQ_STACK_START
+ .endm
+
+ .macro get_fiq_stack @ setup FIQ stack
+ ldr sp, FIQ_STACK_START
+ .endm
+
+/*
+ * exception handlers
+ */
+ .align 5
+undefined_instruction:
+ get_bad_stack
+ bad_save_user_regs
+ bl do_undefined_instruction
+
+ .align 5
+software_interrupt:
+ get_bad_stack_swi
+ bad_save_user_regs
+ bl do_software_interrupt
+
+ .align 5
+prefetch_abort:
+ get_bad_stack
+ bad_save_user_regs
+ bl do_prefetch_abort
+
+ .align 5
+data_abort:
+ get_bad_stack
+ bad_save_user_regs
+ bl do_data_abort
+
+ .align 5
+not_used:
+ get_bad_stack
+ bad_save_user_regs
+ bl do_not_used
+
+#ifdef CONFIG_USE_IRQ
+
+ .align 5
+irq:
+ get_irq_stack
+ irq_save_user_regs
+ bl do_irq
+ irq_restore_user_regs
+
+ .align 5
+fiq:
+ get_fiq_stack
+ /* someone ought to write a more effective fiq_save_user_regs */
+ irq_save_user_regs
+ bl do_fiq
+ irq_restore_user_regs
+
+#else
+
+ .align 5
+irq:
+ get_bad_stack
+ bad_save_user_regs
+ bl do_irq
+
+ .align 5
+fiq:
+ get_bad_stack
+ bad_save_user_regs
+ bl do_fiq
+
+#endif /* CONFIG_USE_IRQ */
+#endif /* CONFIG_SPL_BUILD */
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