[U-Boot] [PATCH 26/26 v2][NEXT] ARM: implement relocation for arm1176
Heiko Schocher
hs at denx.de
Fri Sep 17 13:10:53 CEST 2010
Change the implementation for arm1176 to relocate the code to
an arbitrary address in RAM.
Portions of this work were supported by funding from
the CE Linux Forum.
Signed-off-by: Heiko Schocher <hs at denx.de>
---
arch/arm/cpu/arm1176/start.S | 286 +++++++++++++++++++++++++++++++++++++++
arch/arm/cpu/arm1176/u-boot.lds | 14 ++-
2 files changed, 299 insertions(+), 1 deletions(-)
diff --git a/arch/arm/cpu/arm1176/start.S b/arch/arm/cpu/arm1176/start.S
index f98a7aa..e5e7913 100644
--- a/arch/arm/cpu/arm1176/start.S
+++ b/arch/arm/cpu/arm1176/start.S
@@ -95,6 +95,7 @@ _end_vect:
*************************************************************************
*/
+.globl _TEXT_BASE
_TEXT_BASE:
.word TEXT_BASE
@@ -106,9 +107,11 @@ _TEXT_BASE:
_TEXT_PHY_BASE:
.word CONFIG_SYS_PHY_UBOOT_BASE
+#if defined(CONFIG_SYS_ARM_WITHOUT_RELOC)
.globl _armboot_start
_armboot_start:
.word _start
+#endif
/*
* These are defined in the board-specific linker script.
@@ -121,6 +124,275 @@ _bss_start:
_bss_end:
.word _end
+#if !defined(CONFIG_SYS_ARM_WITHOUT_RELOC)
+/* IRQ stack memory (calculated at run-time) + 8 bytes */
+.globl IRQ_STACK_START_IN
+IRQ_STACK_START_IN:
+ .word 0x0badc0de
+
+.globl _datarel_start
+_datarel_start:
+ .word __datarel_start
+
+.globl _datarelrolocal_start
+_datarelrolocal_start:
+ .word __datarelrolocal_start
+
+.globl _datarellocal_start
+_datarellocal_start:
+ .word __datarellocal_start
+
+.globl _datarelro_start
+_datarelro_start:
+ .word __datarelro_start
+
+.globl _got_start
+_got_start:
+ .word __got_start
+
+.globl _got_end
+_got_end:
+ .word __got_end
+
+/*
+ * the actual reset code
+ */
+
+reset:
+ /*
+ * set the cpu to SVC32 mode
+ */
+ mrs r0, cpsr
+ bic r0, r0, #0x3f
+ orr r0, r0, #0xd3
+ msr cpsr, r0
+
+/*
+ *************************************************************************
+ *
+ * CPU_init_critical registers
+ *
+ * setup important registers
+ * setup memory timing
+ *
+ *************************************************************************
+ */
+ /*
+ * we do sys-critical inits only at reboot,
+ * not when booting from ram!
+ */
+cpu_init_crit:
+ /*
+ * When booting from NAND - it has definitely been a reset, so, no need
+ * to flush caches and disable the MMU
+ */
+#ifndef CONFIG_NAND_SPL
+ /*
+ * flush v4 I/D caches
+ */
+ mov r0, #0
+ mcr p15, 0, r0, c7, c7, 0 /* flush v3/v4 cache */
+ mcr p15, 0, r0, c8, c7, 0 /* flush v4 TLB */
+
+ /*
+ * disable MMU stuff and caches
+ */
+ mrc p15, 0, r0, c1, c0, 0
+ bic r0, r0, #0x00002300 @ clear bits 13, 9:8 (--V- --RS)
+ bic r0, r0, #0x00000087 @ clear bits 7, 2:0 (B--- -CAM)
+ orr r0, r0, #0x00000002 @ set bit 2 (A) Align
+ orr r0, r0, #0x00001000 @ set bit 12 (I) I-Cache
+
+ /* Prepare to disable the MMU */
+ adr r2, mmu_disable_phys
+ sub r2, r2, #(CONFIG_SYS_PHY_UBOOT_BASE - TEXT_BASE)
+ b mmu_disable
+
+ .align 5
+ /* Run in a single cache-line */
+mmu_disable:
+ mcr p15, 0, r0, c1, c0, 0
+ nop
+ nop
+ mov pc, r2
+mmu_disable_phys:
+
+#ifdef CONFIG_DISABLE_TCM
+ /*
+ * Disable the TCMs
+ */
+ mrc p15, 0, r0, c0, c0, 2 /* Return TCM details */
+ cmp r0, #0
+ beq skip_tcmdisable
+ mov r1, #0
+ mov r2, #1
+ tst r0, r2
+ mcrne p15, 0, r1, c9, c1, 1 /* Disable Instruction TCM if present*/
+ tst r0, r2, LSL #16
+ mcrne p15, 0, r1, c9, c1, 0 /* Disable Data TCM if present*/
+skip_tcmdisable:
+#endif
+#endif
+
+#ifdef CONFIG_PERIPORT_REMAP
+ /* Peri port setup */
+ ldr r0, =CONFIG_PERIPORT_BASE
+ orr r0, r0, #CONFIG_PERIPORT_SIZE
+ mcr p15,0,r0,c15,c2,4
+#endif
+
+ /*
+ * Go setup Memory and board specific bits prior to relocation.
+ */
+ bl lowlevel_init /* go setup pll,mux,memory */
+
+/* Set stackpointer in internal RAM to call board_init_f */
+call_board_init_f:
+ ldr sp, =(CONFIG_SYS_INIT_SP_ADDR)
+ ldr r0,=0x00000000
+ bl board_init_f
+
+/*------------------------------------------------------------------------------*/
+
+/*
+ * 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 */
+ mov r7, r2 /* save addr of destination */
+
+ /* Set up the stack */
+stack_setup:
+ mov sp, r4
+
+ adr r0, _start
+ ldr r2, _TEXT_BASE
+ ldr r3, _bss_start
+ sub r2, r3, r2 /* r2 <- size of armboot */
+ add r2, r0, r2 /* r2 <- source end address */
+ cmp r0, r6
+ beq clear_bss
+
+#ifndef CONFIG_SKIP_RELOCATE_UBOOT
+copy_loop:
+ ldmia r0!, {r9-r10} /* copy from source address [r0] */
+ stmia r6!, {r9-r10} /* copy to target address [r1] */
+ cmp r0, r2 /* until source end addreee [r2] */
+ ble copy_loop
+
+#ifndef CONFIG_PRELOADER
+ /* fix got entries */
+ ldr r1, _TEXT_BASE /* Text base */
+ mov r0, r7 /* reloc addr */
+ ldr r2, _got_start /* addr in Flash */
+ ldr r3, _got_end /* addr in Flash */
+ sub r3, r3, r1
+ add r3, r3, r0
+ sub r2, r2, r1
+ add r2, r2, r0
+
+fixloop:
+ ldr r4, [r2]
+ sub r4, r4, r1
+ add r4, r4, r0
+ str r4, [r2]
+ add r2, r2, #4
+ cmp r2, r3
+ bne fixloop
+#endif
+#endif /* #ifndef CONFIG_SKIP_RELOCATE_UBOOT */
+
+#ifdef CONFIG_ENABLE_MMU
+enable_mmu:
+ /* enable domain access */
+ ldr r5, =0x0000ffff
+ mcr p15, 0, r5, c3, c0, 0 /* load domain access register */
+
+ /* Set the TTB register */
+ ldr r0, _mmu_table_base
+ ldr r1, =CONFIG_SYS_PHY_UBOOT_BASE
+ ldr r2, =0xfff00000
+ bic r0, r0, r2
+ orr r1, r0, r1
+ mcr p15, 0, r1, c2, c0, 0
+
+ /* Enable the MMU */
+ mrc p15, 0, r0, c1, c0, 0
+ orr r0, r0, #1 /* Set CR_M to enable MMU */
+
+ /* Prepare to enable the MMU */
+ adr r1, skip_hw_init
+ and r1, r1, #0x3fc
+ ldr r2, _TEXT_BASE
+ ldr r3, =0xfff00000
+ and r2, r2, r3
+ orr r2, r2, r1
+ b mmu_enable
+
+ .align 5
+ /* Run in a single cache-line */
+mmu_enable:
+
+ mcr p15, 0, r0, c1, c0, 0
+ nop
+ nop
+ mov pc, r2
+skip_hw_init:
+#endif
+
+clear_bss:
+#ifndef CONFIG_PRELOADER
+ ldr r0, _bss_start
+ ldr r1, _bss_end
+ ldr r3, _TEXT_BASE /* Text base */
+ mov r4, r7 /* reloc addr */
+ sub r0, r0, r3
+ add r0, r0, r4
+ sub r1, r1, r3
+ add r1, r1, r4
+ mov r2, #0x00000000 /* clear */
+
+clbss_l:str r2, [r0] /* clear loop... */
+ add r0, r0, #4
+ cmp r0, r1
+ bne clbss_l
+
+ bl coloured_LED_init
+ bl red_LED_on
+#endif
+
+/*
+ * We are done. Do not return, instead branch to second part of board
+ * initialization, now running from RAM.
+ */
+#ifdef CONFIG_NAND_SPL
+ ldr pc, _nand_boot
+
+_nand_boot: .word nand_boot
+#else
+ ldr r0, _TEXT_BASE
+ ldr r2, _board_init_r
+ sub r2, r2, r0
+ add r2, r2, r7 /* position from board_init_r in RAM */
+ /* setup parameters for board_init_r */
+ mov r0, r5 /* gd_t */
+ mov r1, r7 /* dest_addr */
+ /* jump to it ... */
+ mov lr, r2
+ mov pc, lr
+
+_board_init_r: .word board_init_r
+#endif
+
+#else /* #if !defined(CONFIG_SYS_ARM_WITHOUT_RELOC) */
+
/*
* the actual reset code
*/
@@ -299,6 +571,8 @@ _start_armboot:
/* .word nand_boot*/
#endif
+#endif /* #if !defined(CONFIG_SYS_ARM_WITHOUT_RELOC) */
+
#ifdef CONFIG_ENABLE_MMU
_mmu_table_base:
.word mmu_table
@@ -385,10 +659,14 @@ phy_last_jump:
/* Save user registers (now in svc mode) r0-r12 */
stmia sp, {r0 - r12}
+#if defined(CONFIG_SYS_ARM_WITHOUT_RELOC)
ldr r2, _armboot_start
sub r2, r2, #(CONFIG_SYS_MALLOC_LEN)
/* set base 2 words into abort stack */
sub r2, r2, #(CONFIG_SYS_GBL_DATA_SIZE+8)
+#else
+ ldr r2, IRQ_STACK_START_IN
+#endif
/* get values for "aborted" pc and cpsr (into parm regs) */
ldmia r2, {r2 - r3}
/* grab pointer to old stack */
@@ -403,12 +681,16 @@ phy_last_jump:
.endm
.macro get_bad_stack
+#if defined(CONFIG_SYS_ARM_WITHOUT_RELOC)
/* setup our mode stack (enter in banked mode) */
ldr r13, _armboot_start
/* move past malloc pool */
sub r13, r13, #(CONFIG_SYS_MALLOC_LEN)
/* move to reserved a couple spots for abort stack */
sub r13, r13, #(CONFIG_SYS_GBL_DATA_SIZE + 8)
+#else
+ ldr r13, IRQ_STACK_START_IN @ setup our mode stack
+#endif
/* save caller lr in position 0 of saved stack */
str lr, [r13]
@@ -433,12 +715,16 @@ phy_last_jump:
sub r13, r13, #4
/* save R0's value. */
str r0, [r13]
+#if defined(CONFIG_SYS_ARM_WITHOUT_RELOC)
/* get data regions start */
ldr r0, _armboot_start
/* move past malloc pool */
sub r0, r0, #(CONFIG_SYS_MALLOC_LEN)
/* move past gbl and a couple spots for abort stack */
sub r0, r0, #(CONFIG_SYS_GBL_DATA_SIZE + 8)
+#else
+ ldr r13, IRQ_STACK_START_IN @ setup our mode stack
+#endif
/* save caller lr in position 0 of saved stack */
str lr, [r0]
/* get the spsr */
diff --git a/arch/arm/cpu/arm1176/u-boot.lds b/arch/arm/cpu/arm1176/u-boot.lds
index 8969587..fa640ee 100644
--- a/arch/arm/cpu/arm1176/u-boot.lds
+++ b/arch/arm/cpu/arm1176/u-boot.lds
@@ -39,11 +39,23 @@ SECTIONS
.rodata : { *(SORT_BY_ALIGNMENT(SORT_BY_NAME(.rodata*))) }
. = ALIGN(4);
- .data : { *(.data) }
+ .data : {
+ *(.data)
+ __datarel_start = .;
+ *(.data.rel)
+ __datarelrolocal_start = .;
+ *(.data.rel.ro.local)
+ __datarellocal_start = .;
+ *(.data.rel.local)
+ __datarelro_start = .;
+ *(.data.rel.ro)
+ }
+ __got_start = .;
. = ALIGN(4);
.got : { *(.got) }
+ __got_end = .;
. = .;
__u_boot_cmd_start = .;
.u_boot_cmd : { *(.u_boot_cmd) }
--
1.6.2.5
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