linux/arch/arm/boot/compressed/head.S
Srinivas Ramana 117e5e9c4c ARM: 8618/1: decompressor: reset ttbcr fields to use TTBR0 on ARMv7
If the bootloader uses the long descriptor format and jumps to
kernel decompressor code, TTBCR may not be in a right state.
Before enabling the MMU, it is required to clear the TTBCR.PD0
field to use TTBR0 for translation table walks.

The commit dbece45894 ("ARM: 7501/1: decompressor:
reset ttbcr for VMSA ARMv7 cores") does the reset of TTBCR.N, but
doesn't consider all the bits for the size of TTBCR.N.

Clear TTBCR.PD0 field and reset all the three bits of TTBCR.N to
indicate the use of TTBR0 and the correct base address width.

Fixes: dbece45894 ("ARM: 7501/1: decompressor: reset ttbcr for VMSA ARMv7 cores")
Acked-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Srinivas Ramana <sramana@codeaurora.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2016-10-02 20:05:14 +01:00

1410 lines
35 KiB
ArmAsm

/*
* linux/arch/arm/boot/compressed/head.S
*
* Copyright (C) 1996-2002 Russell King
* Copyright (C) 2004 Hyok S. Choi (MPU support)
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/linkage.h>
#include <asm/assembler.h>
#include <asm/v7m.h>
#include "efi-header.S"
AR_CLASS( .arch armv7-a )
M_CLASS( .arch armv7-m )
/*
* Debugging stuff
*
* Note that these macros must not contain any code which is not
* 100% relocatable. Any attempt to do so will result in a crash.
* Please select one of the following when turning on debugging.
*/
#ifdef DEBUG
#if defined(CONFIG_DEBUG_ICEDCC)
#if defined(CONFIG_CPU_V6) || defined(CONFIG_CPU_V6K) || defined(CONFIG_CPU_V7)
.macro loadsp, rb, tmp
.endm
.macro writeb, ch, rb
mcr p14, 0, \ch, c0, c5, 0
.endm
#elif defined(CONFIG_CPU_XSCALE)
.macro loadsp, rb, tmp
.endm
.macro writeb, ch, rb
mcr p14, 0, \ch, c8, c0, 0
.endm
#else
.macro loadsp, rb, tmp
.endm
.macro writeb, ch, rb
mcr p14, 0, \ch, c1, c0, 0
.endm
#endif
#else
#include CONFIG_DEBUG_LL_INCLUDE
.macro writeb, ch, rb
senduart \ch, \rb
.endm
#if defined(CONFIG_ARCH_SA1100)
.macro loadsp, rb, tmp
mov \rb, #0x80000000 @ physical base address
#ifdef CONFIG_DEBUG_LL_SER3
add \rb, \rb, #0x00050000 @ Ser3
#else
add \rb, \rb, #0x00010000 @ Ser1
#endif
.endm
#else
.macro loadsp, rb, tmp
addruart \rb, \tmp
.endm
#endif
#endif
#endif
.macro kputc,val
mov r0, \val
bl putc
.endm
.macro kphex,val,len
mov r0, \val
mov r1, #\len
bl phex
.endm
.macro debug_reloc_start
#ifdef DEBUG
kputc #'\n'
kphex r6, 8 /* processor id */
kputc #':'
kphex r7, 8 /* architecture id */
#ifdef CONFIG_CPU_CP15
kputc #':'
mrc p15, 0, r0, c1, c0
kphex r0, 8 /* control reg */
#endif
kputc #'\n'
kphex r5, 8 /* decompressed kernel start */
kputc #'-'
kphex r9, 8 /* decompressed kernel end */
kputc #'>'
kphex r4, 8 /* kernel execution address */
kputc #'\n'
#endif
.endm
.macro debug_reloc_end
#ifdef DEBUG
kphex r5, 8 /* end of kernel */
kputc #'\n'
mov r0, r4
bl memdump /* dump 256 bytes at start of kernel */
#endif
.endm
.section ".start", #alloc, #execinstr
/*
* sort out different calling conventions
*/
.align
/*
* Always enter in ARM state for CPUs that support the ARM ISA.
* As of today (2014) that's exactly the members of the A and R
* classes.
*/
AR_CLASS( .arm )
start:
.type start,#function
.rept 7
__nop
.endr
ARM( mov r0, r0 )
ARM( b 1f )
THUMB( badr r12, 1f )
THUMB( bx r12 )
.word _magic_sig @ Magic numbers to help the loader
.word _magic_start @ absolute load/run zImage address
.word _magic_end @ zImage end address
.word 0x04030201 @ endianness flag
THUMB( .thumb )
1: __EFI_HEADER
ARM_BE8( setend be ) @ go BE8 if compiled for BE8
AR_CLASS( mrs r9, cpsr )
#ifdef CONFIG_ARM_VIRT_EXT
bl __hyp_stub_install @ get into SVC mode, reversibly
#endif
mov r7, r1 @ save architecture ID
mov r8, r2 @ save atags pointer
#ifndef CONFIG_CPU_V7M
/*
* Booting from Angel - need to enter SVC mode and disable
* FIQs/IRQs (numeric definitions from angel arm.h source).
* We only do this if we were in user mode on entry.
*/
mrs r2, cpsr @ get current mode
tst r2, #3 @ not user?
bne not_angel
mov r0, #0x17 @ angel_SWIreason_EnterSVC
ARM( swi 0x123456 ) @ angel_SWI_ARM
THUMB( svc 0xab ) @ angel_SWI_THUMB
not_angel:
safe_svcmode_maskall r0
msr spsr_cxsf, r9 @ Save the CPU boot mode in
@ SPSR
#endif
/*
* Note that some cache flushing and other stuff may
* be needed here - is there an Angel SWI call for this?
*/
/*
* some architecture specific code can be inserted
* by the linker here, but it should preserve r7, r8, and r9.
*/
.text
#ifdef CONFIG_AUTO_ZRELADDR
/*
* Find the start of physical memory. As we are executing
* without the MMU on, we are in the physical address space.
* We just need to get rid of any offset by aligning the
* address.
*
* This alignment is a balance between the requirements of
* different platforms - we have chosen 128MB to allow
* platforms which align the start of their physical memory
* to 128MB to use this feature, while allowing the zImage
* to be placed within the first 128MB of memory on other
* platforms. Increasing the alignment means we place
* stricter alignment requirements on the start of physical
* memory, but relaxing it means that we break people who
* are already placing their zImage in (eg) the top 64MB
* of this range.
*/
mov r4, pc
and r4, r4, #0xf8000000
/* Determine final kernel image address. */
add r4, r4, #TEXT_OFFSET
#else
ldr r4, =zreladdr
#endif
/*
* Set up a page table only if it won't overwrite ourself.
* That means r4 < pc || r4 - 16k page directory > &_end.
* Given that r4 > &_end is most unfrequent, we add a rough
* additional 1MB of room for a possible appended DTB.
*/
mov r0, pc
cmp r0, r4
ldrcc r0, LC0+32
addcc r0, r0, pc
cmpcc r4, r0
orrcc r4, r4, #1 @ remember we skipped cache_on
blcs cache_on
restart: adr r0, LC0
ldmia r0, {r1, r2, r3, r6, r10, r11, r12}
ldr sp, [r0, #28]
/*
* We might be running at a different address. We need
* to fix up various pointers.
*/
sub r0, r0, r1 @ calculate the delta offset
add r6, r6, r0 @ _edata
add r10, r10, r0 @ inflated kernel size location
/*
* The kernel build system appends the size of the
* decompressed kernel at the end of the compressed data
* in little-endian form.
*/
ldrb r9, [r10, #0]
ldrb lr, [r10, #1]
orr r9, r9, lr, lsl #8
ldrb lr, [r10, #2]
ldrb r10, [r10, #3]
orr r9, r9, lr, lsl #16
orr r9, r9, r10, lsl #24
#ifndef CONFIG_ZBOOT_ROM
/* malloc space is above the relocated stack (64k max) */
add sp, sp, r0
add r10, sp, #0x10000
#else
/*
* With ZBOOT_ROM the bss/stack is non relocatable,
* but someone could still run this code from RAM,
* in which case our reference is _edata.
*/
mov r10, r6
#endif
mov r5, #0 @ init dtb size to 0
#ifdef CONFIG_ARM_APPENDED_DTB
/*
* r0 = delta
* r2 = BSS start
* r3 = BSS end
* r4 = final kernel address (possibly with LSB set)
* r5 = appended dtb size (still unknown)
* r6 = _edata
* r7 = architecture ID
* r8 = atags/device tree pointer
* r9 = size of decompressed image
* r10 = end of this image, including bss/stack/malloc space if non XIP
* r11 = GOT start
* r12 = GOT end
* sp = stack pointer
*
* if there are device trees (dtb) appended to zImage, advance r10 so that the
* dtb data will get relocated along with the kernel if necessary.
*/
ldr lr, [r6, #0]
#ifndef __ARMEB__
ldr r1, =0xedfe0dd0 @ sig is 0xd00dfeed big endian
#else
ldr r1, =0xd00dfeed
#endif
cmp lr, r1
bne dtb_check_done @ not found
#ifdef CONFIG_ARM_ATAG_DTB_COMPAT
/*
* OK... Let's do some funky business here.
* If we do have a DTB appended to zImage, and we do have
* an ATAG list around, we want the later to be translated
* and folded into the former here. No GOT fixup has occurred
* yet, but none of the code we're about to call uses any
* global variable.
*/
/* Get the initial DTB size */
ldr r5, [r6, #4]
#ifndef __ARMEB__
/* convert to little endian */
eor r1, r5, r5, ror #16
bic r1, r1, #0x00ff0000
mov r5, r5, ror #8
eor r5, r5, r1, lsr #8
#endif
/* 50% DTB growth should be good enough */
add r5, r5, r5, lsr #1
/* preserve 64-bit alignment */
add r5, r5, #7
bic r5, r5, #7
/* clamp to 32KB min and 1MB max */
cmp r5, #(1 << 15)
movlo r5, #(1 << 15)
cmp r5, #(1 << 20)
movhi r5, #(1 << 20)
/* temporarily relocate the stack past the DTB work space */
add sp, sp, r5
stmfd sp!, {r0-r3, ip, lr}
mov r0, r8
mov r1, r6
mov r2, r5
bl atags_to_fdt
/*
* If returned value is 1, there is no ATAG at the location
* pointed by r8. Try the typical 0x100 offset from start
* of RAM and hope for the best.
*/
cmp r0, #1
sub r0, r4, #TEXT_OFFSET
bic r0, r0, #1
add r0, r0, #0x100
mov r1, r6
mov r2, r5
bleq atags_to_fdt
ldmfd sp!, {r0-r3, ip, lr}
sub sp, sp, r5
#endif
mov r8, r6 @ use the appended device tree
/*
* Make sure that the DTB doesn't end up in the final
* kernel's .bss area. To do so, we adjust the decompressed
* kernel size to compensate if that .bss size is larger
* than the relocated code.
*/
ldr r5, =_kernel_bss_size
adr r1, wont_overwrite
sub r1, r6, r1
subs r1, r5, r1
addhi r9, r9, r1
/* Get the current DTB size */
ldr r5, [r6, #4]
#ifndef __ARMEB__
/* convert r5 (dtb size) to little endian */
eor r1, r5, r5, ror #16
bic r1, r1, #0x00ff0000
mov r5, r5, ror #8
eor r5, r5, r1, lsr #8
#endif
/* preserve 64-bit alignment */
add r5, r5, #7
bic r5, r5, #7
/* relocate some pointers past the appended dtb */
add r6, r6, r5
add r10, r10, r5
add sp, sp, r5
dtb_check_done:
#endif
/*
* Check to see if we will overwrite ourselves.
* r4 = final kernel address (possibly with LSB set)
* r9 = size of decompressed image
* r10 = end of this image, including bss/stack/malloc space if non XIP
* We basically want:
* r4 - 16k page directory >= r10 -> OK
* r4 + image length <= address of wont_overwrite -> OK
* Note: the possible LSB in r4 is harmless here.
*/
add r10, r10, #16384
cmp r4, r10
bhs wont_overwrite
add r10, r4, r9
adr r9, wont_overwrite
cmp r10, r9
bls wont_overwrite
/*
* Relocate ourselves past the end of the decompressed kernel.
* r6 = _edata
* r10 = end of the decompressed kernel
* Because we always copy ahead, we need to do it from the end and go
* backward in case the source and destination overlap.
*/
/*
* Bump to the next 256-byte boundary with the size of
* the relocation code added. This avoids overwriting
* ourself when the offset is small.
*/
add r10, r10, #((reloc_code_end - restart + 256) & ~255)
bic r10, r10, #255
/* Get start of code we want to copy and align it down. */
adr r5, restart
bic r5, r5, #31
/* Relocate the hyp vector base if necessary */
#ifdef CONFIG_ARM_VIRT_EXT
mrs r0, spsr
and r0, r0, #MODE_MASK
cmp r0, #HYP_MODE
bne 1f
bl __hyp_get_vectors
sub r0, r0, r5
add r0, r0, r10
bl __hyp_set_vectors
1:
#endif
sub r9, r6, r5 @ size to copy
add r9, r9, #31 @ rounded up to a multiple
bic r9, r9, #31 @ ... of 32 bytes
add r6, r9, r5
add r9, r9, r10
1: ldmdb r6!, {r0 - r3, r10 - r12, lr}
cmp r6, r5
stmdb r9!, {r0 - r3, r10 - r12, lr}
bhi 1b
/* Preserve offset to relocated code. */
sub r6, r9, r6
#ifndef CONFIG_ZBOOT_ROM
/* cache_clean_flush may use the stack, so relocate it */
add sp, sp, r6
#endif
bl cache_clean_flush
badr r0, restart
add r0, r0, r6
mov pc, r0
wont_overwrite:
/*
* If delta is zero, we are running at the address we were linked at.
* r0 = delta
* r2 = BSS start
* r3 = BSS end
* r4 = kernel execution address (possibly with LSB set)
* r5 = appended dtb size (0 if not present)
* r7 = architecture ID
* r8 = atags pointer
* r11 = GOT start
* r12 = GOT end
* sp = stack pointer
*/
orrs r1, r0, r5
beq not_relocated
add r11, r11, r0
add r12, r12, r0
#ifndef CONFIG_ZBOOT_ROM
/*
* If we're running fully PIC === CONFIG_ZBOOT_ROM = n,
* we need to fix up pointers into the BSS region.
* Note that the stack pointer has already been fixed up.
*/
add r2, r2, r0
add r3, r3, r0
/*
* Relocate all entries in the GOT table.
* Bump bss entries to _edata + dtb size
*/
1: ldr r1, [r11, #0] @ relocate entries in the GOT
add r1, r1, r0 @ This fixes up C references
cmp r1, r2 @ if entry >= bss_start &&
cmphs r3, r1 @ bss_end > entry
addhi r1, r1, r5 @ entry += dtb size
str r1, [r11], #4 @ next entry
cmp r11, r12
blo 1b
/* bump our bss pointers too */
add r2, r2, r5
add r3, r3, r5
#else
/*
* Relocate entries in the GOT table. We only relocate
* the entries that are outside the (relocated) BSS region.
*/
1: ldr r1, [r11, #0] @ relocate entries in the GOT
cmp r1, r2 @ entry < bss_start ||
cmphs r3, r1 @ _end < entry
addlo r1, r1, r0 @ table. This fixes up the
str r1, [r11], #4 @ C references.
cmp r11, r12
blo 1b
#endif
not_relocated: mov r0, #0
1: str r0, [r2], #4 @ clear bss
str r0, [r2], #4
str r0, [r2], #4
str r0, [r2], #4
cmp r2, r3
blo 1b
/*
* Did we skip the cache setup earlier?
* That is indicated by the LSB in r4.
* Do it now if so.
*/
tst r4, #1
bic r4, r4, #1
blne cache_on
/*
* The C runtime environment should now be setup sufficiently.
* Set up some pointers, and start decompressing.
* r4 = kernel execution address
* r7 = architecture ID
* r8 = atags pointer
*/
mov r0, r4
mov r1, sp @ malloc space above stack
add r2, sp, #0x10000 @ 64k max
mov r3, r7
bl decompress_kernel
bl cache_clean_flush
bl cache_off
mov r1, r7 @ restore architecture number
mov r2, r8 @ restore atags pointer
#ifdef CONFIG_ARM_VIRT_EXT
mrs r0, spsr @ Get saved CPU boot mode
and r0, r0, #MODE_MASK
cmp r0, #HYP_MODE @ if not booted in HYP mode...
bne __enter_kernel @ boot kernel directly
adr r12, .L__hyp_reentry_vectors_offset
ldr r0, [r12]
add r0, r0, r12
bl __hyp_set_vectors
__HVC(0) @ otherwise bounce to hyp mode
b . @ should never be reached
.align 2
.L__hyp_reentry_vectors_offset: .long __hyp_reentry_vectors - .
#else
b __enter_kernel
#endif
.align 2
.type LC0, #object
LC0: .word LC0 @ r1
.word __bss_start @ r2
.word _end @ r3
.word _edata @ r6
.word input_data_end - 4 @ r10 (inflated size location)
.word _got_start @ r11
.word _got_end @ ip
.word .L_user_stack_end @ sp
.word _end - restart + 16384 + 1024*1024
.size LC0, . - LC0
#ifdef CONFIG_ARCH_RPC
.globl params
params: ldr r0, =0x10000100 @ params_phys for RPC
mov pc, lr
.ltorg
.align
#endif
/*
* Turn on the cache. We need to setup some page tables so that we
* can have both the I and D caches on.
*
* We place the page tables 16k down from the kernel execution address,
* and we hope that nothing else is using it. If we're using it, we
* will go pop!
*
* On entry,
* r4 = kernel execution address
* r7 = architecture number
* r8 = atags pointer
* On exit,
* r0, r1, r2, r3, r9, r10, r12 corrupted
* This routine must preserve:
* r4, r7, r8
*/
.align 5
cache_on: mov r3, #8 @ cache_on function
b call_cache_fn
/*
* Initialize the highest priority protection region, PR7
* to cover all 32bit address and cacheable and bufferable.
*/
__armv4_mpu_cache_on:
mov r0, #0x3f @ 4G, the whole
mcr p15, 0, r0, c6, c7, 0 @ PR7 Area Setting
mcr p15, 0, r0, c6, c7, 1
mov r0, #0x80 @ PR7
mcr p15, 0, r0, c2, c0, 0 @ D-cache on
mcr p15, 0, r0, c2, c0, 1 @ I-cache on
mcr p15, 0, r0, c3, c0, 0 @ write-buffer on
mov r0, #0xc000
mcr p15, 0, r0, c5, c0, 1 @ I-access permission
mcr p15, 0, r0, c5, c0, 0 @ D-access permission
mov r0, #0
mcr p15, 0, r0, c7, c10, 4 @ drain write buffer
mcr p15, 0, r0, c7, c5, 0 @ flush(inval) I-Cache
mcr p15, 0, r0, c7, c6, 0 @ flush(inval) D-Cache
mrc p15, 0, r0, c1, c0, 0 @ read control reg
@ ...I .... ..D. WC.M
orr r0, r0, #0x002d @ .... .... ..1. 11.1
orr r0, r0, #0x1000 @ ...1 .... .... ....
mcr p15, 0, r0, c1, c0, 0 @ write control reg
mov r0, #0
mcr p15, 0, r0, c7, c5, 0 @ flush(inval) I-Cache
mcr p15, 0, r0, c7, c6, 0 @ flush(inval) D-Cache
mov pc, lr
__armv3_mpu_cache_on:
mov r0, #0x3f @ 4G, the whole
mcr p15, 0, r0, c6, c7, 0 @ PR7 Area Setting
mov r0, #0x80 @ PR7
mcr p15, 0, r0, c2, c0, 0 @ cache on
mcr p15, 0, r0, c3, c0, 0 @ write-buffer on
mov r0, #0xc000
mcr p15, 0, r0, c5, c0, 0 @ access permission
mov r0, #0
mcr p15, 0, r0, c7, c0, 0 @ invalidate whole cache v3
/*
* ?? ARMv3 MMU does not allow reading the control register,
* does this really work on ARMv3 MPU?
*/
mrc p15, 0, r0, c1, c0, 0 @ read control reg
@ .... .... .... WC.M
orr r0, r0, #0x000d @ .... .... .... 11.1
/* ?? this overwrites the value constructed above? */
mov r0, #0
mcr p15, 0, r0, c1, c0, 0 @ write control reg
/* ?? invalidate for the second time? */
mcr p15, 0, r0, c7, c0, 0 @ invalidate whole cache v3
mov pc, lr
#ifdef CONFIG_CPU_DCACHE_WRITETHROUGH
#define CB_BITS 0x08
#else
#define CB_BITS 0x0c
#endif
__setup_mmu: sub r3, r4, #16384 @ Page directory size
bic r3, r3, #0xff @ Align the pointer
bic r3, r3, #0x3f00
/*
* Initialise the page tables, turning on the cacheable and bufferable
* bits for the RAM area only.
*/
mov r0, r3
mov r9, r0, lsr #18
mov r9, r9, lsl #18 @ start of RAM
add r10, r9, #0x10000000 @ a reasonable RAM size
mov r1, #0x12 @ XN|U + section mapping
orr r1, r1, #3 << 10 @ AP=11
add r2, r3, #16384
1: cmp r1, r9 @ if virt > start of RAM
cmphs r10, r1 @ && end of RAM > virt
bic r1, r1, #0x1c @ clear XN|U + C + B
orrlo r1, r1, #0x10 @ Set XN|U for non-RAM
orrhs r1, r1, r6 @ set RAM section settings
str r1, [r0], #4 @ 1:1 mapping
add r1, r1, #1048576
teq r0, r2
bne 1b
/*
* If ever we are running from Flash, then we surely want the cache
* to be enabled also for our execution instance... We map 2MB of it
* so there is no map overlap problem for up to 1 MB compressed kernel.
* If the execution is in RAM then we would only be duplicating the above.
*/
orr r1, r6, #0x04 @ ensure B is set for this
orr r1, r1, #3 << 10
mov r2, pc
mov r2, r2, lsr #20
orr r1, r1, r2, lsl #20
add r0, r3, r2, lsl #2
str r1, [r0], #4
add r1, r1, #1048576
str r1, [r0]
mov pc, lr
ENDPROC(__setup_mmu)
@ Enable unaligned access on v6, to allow better code generation
@ for the decompressor C code:
__armv6_mmu_cache_on:
mrc p15, 0, r0, c1, c0, 0 @ read SCTLR
bic r0, r0, #2 @ A (no unaligned access fault)
orr r0, r0, #1 << 22 @ U (v6 unaligned access model)
mcr p15, 0, r0, c1, c0, 0 @ write SCTLR
b __armv4_mmu_cache_on
__arm926ejs_mmu_cache_on:
#ifdef CONFIG_CPU_DCACHE_WRITETHROUGH
mov r0, #4 @ put dcache in WT mode
mcr p15, 7, r0, c15, c0, 0
#endif
__armv4_mmu_cache_on:
mov r12, lr
#ifdef CONFIG_MMU
mov r6, #CB_BITS | 0x12 @ U
bl __setup_mmu
mov r0, #0
mcr p15, 0, r0, c7, c10, 4 @ drain write buffer
mcr p15, 0, r0, c8, c7, 0 @ flush I,D TLBs
mrc p15, 0, r0, c1, c0, 0 @ read control reg
orr r0, r0, #0x5000 @ I-cache enable, RR cache replacement
orr r0, r0, #0x0030
ARM_BE8( orr r0, r0, #1 << 25 ) @ big-endian page tables
bl __common_mmu_cache_on
mov r0, #0
mcr p15, 0, r0, c8, c7, 0 @ flush I,D TLBs
#endif
mov pc, r12
__armv7_mmu_cache_on:
mov r12, lr
#ifdef CONFIG_MMU
mrc p15, 0, r11, c0, c1, 4 @ read ID_MMFR0
tst r11, #0xf @ VMSA
movne r6, #CB_BITS | 0x02 @ !XN
blne __setup_mmu
mov r0, #0
mcr p15, 0, r0, c7, c10, 4 @ drain write buffer
tst r11, #0xf @ VMSA
mcrne p15, 0, r0, c8, c7, 0 @ flush I,D TLBs
#endif
mrc p15, 0, r0, c1, c0, 0 @ read control reg
bic r0, r0, #1 << 28 @ clear SCTLR.TRE
orr r0, r0, #0x5000 @ I-cache enable, RR cache replacement
orr r0, r0, #0x003c @ write buffer
bic r0, r0, #2 @ A (no unaligned access fault)
orr r0, r0, #1 << 22 @ U (v6 unaligned access model)
@ (needed for ARM1176)
#ifdef CONFIG_MMU
ARM_BE8( orr r0, r0, #1 << 25 ) @ big-endian page tables
mrcne p15, 0, r6, c2, c0, 2 @ read ttb control reg
orrne r0, r0, #1 @ MMU enabled
movne r1, #0xfffffffd @ domain 0 = client
bic r6, r6, #1 << 31 @ 32-bit translation system
bic r6, r6, #(7 << 0) | (1 << 4) @ use only ttbr0
mcrne p15, 0, r3, c2, c0, 0 @ load page table pointer
mcrne p15, 0, r1, c3, c0, 0 @ load domain access control
mcrne p15, 0, r6, c2, c0, 2 @ load ttb control
#endif
mcr p15, 0, r0, c7, c5, 4 @ ISB
mcr p15, 0, r0, c1, c0, 0 @ load control register
mrc p15, 0, r0, c1, c0, 0 @ and read it back
mov r0, #0
mcr p15, 0, r0, c7, c5, 4 @ ISB
mov pc, r12
__fa526_cache_on:
mov r12, lr
mov r6, #CB_BITS | 0x12 @ U
bl __setup_mmu
mov r0, #0
mcr p15, 0, r0, c7, c7, 0 @ Invalidate whole cache
mcr p15, 0, r0, c7, c10, 4 @ drain write buffer
mcr p15, 0, r0, c8, c7, 0 @ flush UTLB
mrc p15, 0, r0, c1, c0, 0 @ read control reg
orr r0, r0, #0x1000 @ I-cache enable
bl __common_mmu_cache_on
mov r0, #0
mcr p15, 0, r0, c8, c7, 0 @ flush UTLB
mov pc, r12
__common_mmu_cache_on:
#ifndef CONFIG_THUMB2_KERNEL
#ifndef DEBUG
orr r0, r0, #0x000d @ Write buffer, mmu
#endif
mov r1, #-1
mcr p15, 0, r3, c2, c0, 0 @ load page table pointer
mcr p15, 0, r1, c3, c0, 0 @ load domain access control
b 1f
.align 5 @ cache line aligned
1: mcr p15, 0, r0, c1, c0, 0 @ load control register
mrc p15, 0, r0, c1, c0, 0 @ and read it back to
sub pc, lr, r0, lsr #32 @ properly flush pipeline
#endif
#define PROC_ENTRY_SIZE (4*5)
/*
* Here follow the relocatable cache support functions for the
* various processors. This is a generic hook for locating an
* entry and jumping to an instruction at the specified offset
* from the start of the block. Please note this is all position
* independent code.
*
* r1 = corrupted
* r2 = corrupted
* r3 = block offset
* r9 = corrupted
* r12 = corrupted
*/
call_cache_fn: adr r12, proc_types
#ifdef CONFIG_CPU_CP15
mrc p15, 0, r9, c0, c0 @ get processor ID
#elif defined(CONFIG_CPU_V7M)
/*
* On v7-M the processor id is located in the V7M_SCB_CPUID
* register, but as cache handling is IMPLEMENTATION DEFINED on
* v7-M (if existant at all) we just return early here.
* If V7M_SCB_CPUID were used the cpu ID functions (i.e.
* __armv7_mmu_cache_{on,off,flush}) would be selected which
* use cp15 registers that are not implemented on v7-M.
*/
bx lr
#else
ldr r9, =CONFIG_PROCESSOR_ID
#endif
1: ldr r1, [r12, #0] @ get value
ldr r2, [r12, #4] @ get mask
eor r1, r1, r9 @ (real ^ match)
tst r1, r2 @ & mask
ARM( addeq pc, r12, r3 ) @ call cache function
THUMB( addeq r12, r3 )
THUMB( moveq pc, r12 ) @ call cache function
add r12, r12, #PROC_ENTRY_SIZE
b 1b
/*
* Table for cache operations. This is basically:
* - CPU ID match
* - CPU ID mask
* - 'cache on' method instruction
* - 'cache off' method instruction
* - 'cache flush' method instruction
*
* We match an entry using: ((real_id ^ match) & mask) == 0
*
* Writethrough caches generally only need 'on' and 'off'
* methods. Writeback caches _must_ have the flush method
* defined.
*/
.align 2
.type proc_types,#object
proc_types:
.word 0x41000000 @ old ARM ID
.word 0xff00f000
mov pc, lr
THUMB( nop )
mov pc, lr
THUMB( nop )
mov pc, lr
THUMB( nop )
.word 0x41007000 @ ARM7/710
.word 0xfff8fe00
mov pc, lr
THUMB( nop )
mov pc, lr
THUMB( nop )
mov pc, lr
THUMB( nop )
.word 0x41807200 @ ARM720T (writethrough)
.word 0xffffff00
W(b) __armv4_mmu_cache_on
W(b) __armv4_mmu_cache_off
mov pc, lr
THUMB( nop )
.word 0x41007400 @ ARM74x
.word 0xff00ff00
W(b) __armv3_mpu_cache_on
W(b) __armv3_mpu_cache_off
W(b) __armv3_mpu_cache_flush
.word 0x41009400 @ ARM94x
.word 0xff00ff00
W(b) __armv4_mpu_cache_on
W(b) __armv4_mpu_cache_off
W(b) __armv4_mpu_cache_flush
.word 0x41069260 @ ARM926EJ-S (v5TEJ)
.word 0xff0ffff0
W(b) __arm926ejs_mmu_cache_on
W(b) __armv4_mmu_cache_off
W(b) __armv5tej_mmu_cache_flush
.word 0x00007000 @ ARM7 IDs
.word 0x0000f000
mov pc, lr
THUMB( nop )
mov pc, lr
THUMB( nop )
mov pc, lr
THUMB( nop )
@ Everything from here on will be the new ID system.
.word 0x4401a100 @ sa110 / sa1100
.word 0xffffffe0
W(b) __armv4_mmu_cache_on
W(b) __armv4_mmu_cache_off
W(b) __armv4_mmu_cache_flush
.word 0x6901b110 @ sa1110
.word 0xfffffff0
W(b) __armv4_mmu_cache_on
W(b) __armv4_mmu_cache_off
W(b) __armv4_mmu_cache_flush
.word 0x56056900
.word 0xffffff00 @ PXA9xx
W(b) __armv4_mmu_cache_on
W(b) __armv4_mmu_cache_off
W(b) __armv4_mmu_cache_flush
.word 0x56158000 @ PXA168
.word 0xfffff000
W(b) __armv4_mmu_cache_on
W(b) __armv4_mmu_cache_off
W(b) __armv5tej_mmu_cache_flush
.word 0x56050000 @ Feroceon
.word 0xff0f0000
W(b) __armv4_mmu_cache_on
W(b) __armv4_mmu_cache_off
W(b) __armv5tej_mmu_cache_flush
#ifdef CONFIG_CPU_FEROCEON_OLD_ID
/* this conflicts with the standard ARMv5TE entry */
.long 0x41009260 @ Old Feroceon
.long 0xff00fff0
b __armv4_mmu_cache_on
b __armv4_mmu_cache_off
b __armv5tej_mmu_cache_flush
#endif
.word 0x66015261 @ FA526
.word 0xff01fff1
W(b) __fa526_cache_on
W(b) __armv4_mmu_cache_off
W(b) __fa526_cache_flush
@ These match on the architecture ID
.word 0x00020000 @ ARMv4T
.word 0x000f0000
W(b) __armv4_mmu_cache_on
W(b) __armv4_mmu_cache_off
W(b) __armv4_mmu_cache_flush
.word 0x00050000 @ ARMv5TE
.word 0x000f0000
W(b) __armv4_mmu_cache_on
W(b) __armv4_mmu_cache_off
W(b) __armv4_mmu_cache_flush
.word 0x00060000 @ ARMv5TEJ
.word 0x000f0000
W(b) __armv4_mmu_cache_on
W(b) __armv4_mmu_cache_off
W(b) __armv5tej_mmu_cache_flush
.word 0x0007b000 @ ARMv6
.word 0x000ff000
W(b) __armv6_mmu_cache_on
W(b) __armv4_mmu_cache_off
W(b) __armv6_mmu_cache_flush
.word 0x000f0000 @ new CPU Id
.word 0x000f0000
W(b) __armv7_mmu_cache_on
W(b) __armv7_mmu_cache_off
W(b) __armv7_mmu_cache_flush
.word 0 @ unrecognised type
.word 0
mov pc, lr
THUMB( nop )
mov pc, lr
THUMB( nop )
mov pc, lr
THUMB( nop )
.size proc_types, . - proc_types
/*
* If you get a "non-constant expression in ".if" statement"
* error from the assembler on this line, check that you have
* not accidentally written a "b" instruction where you should
* have written W(b).
*/
.if (. - proc_types) % PROC_ENTRY_SIZE != 0
.error "The size of one or more proc_types entries is wrong."
.endif
/*
* Turn off the Cache and MMU. ARMv3 does not support
* reading the control register, but ARMv4 does.
*
* On exit,
* r0, r1, r2, r3, r9, r12 corrupted
* This routine must preserve:
* r4, r7, r8
*/
.align 5
cache_off: mov r3, #12 @ cache_off function
b call_cache_fn
__armv4_mpu_cache_off:
mrc p15, 0, r0, c1, c0
bic r0, r0, #0x000d
mcr p15, 0, r0, c1, c0 @ turn MPU and cache off
mov r0, #0
mcr p15, 0, r0, c7, c10, 4 @ drain write buffer
mcr p15, 0, r0, c7, c6, 0 @ flush D-Cache
mcr p15, 0, r0, c7, c5, 0 @ flush I-Cache
mov pc, lr
__armv3_mpu_cache_off:
mrc p15, 0, r0, c1, c0
bic r0, r0, #0x000d
mcr p15, 0, r0, c1, c0, 0 @ turn MPU and cache off
mov r0, #0
mcr p15, 0, r0, c7, c0, 0 @ invalidate whole cache v3
mov pc, lr
__armv4_mmu_cache_off:
#ifdef CONFIG_MMU
mrc p15, 0, r0, c1, c0
bic r0, r0, #0x000d
mcr p15, 0, r0, c1, c0 @ turn MMU and cache off
mov r0, #0
mcr p15, 0, r0, c7, c7 @ invalidate whole cache v4
mcr p15, 0, r0, c8, c7 @ invalidate whole TLB v4
#endif
mov pc, lr
__armv7_mmu_cache_off:
mrc p15, 0, r0, c1, c0
#ifdef CONFIG_MMU
bic r0, r0, #0x000d
#else
bic r0, r0, #0x000c
#endif
mcr p15, 0, r0, c1, c0 @ turn MMU and cache off
mov r12, lr
bl __armv7_mmu_cache_flush
mov r0, #0
#ifdef CONFIG_MMU
mcr p15, 0, r0, c8, c7, 0 @ invalidate whole TLB
#endif
mcr p15, 0, r0, c7, c5, 6 @ invalidate BTC
mcr p15, 0, r0, c7, c10, 4 @ DSB
mcr p15, 0, r0, c7, c5, 4 @ ISB
mov pc, r12
/*
* Clean and flush the cache to maintain consistency.
*
* On exit,
* r1, r2, r3, r9, r10, r11, r12 corrupted
* This routine must preserve:
* r4, r6, r7, r8
*/
.align 5
cache_clean_flush:
mov r3, #16
b call_cache_fn
__armv4_mpu_cache_flush:
tst r4, #1
movne pc, lr
mov r2, #1
mov r3, #0
mcr p15, 0, ip, c7, c6, 0 @ invalidate D cache
mov r1, #7 << 5 @ 8 segments
1: orr r3, r1, #63 << 26 @ 64 entries
2: mcr p15, 0, r3, c7, c14, 2 @ clean & invalidate D index
subs r3, r3, #1 << 26
bcs 2b @ entries 63 to 0
subs r1, r1, #1 << 5
bcs 1b @ segments 7 to 0
teq r2, #0
mcrne p15, 0, ip, c7, c5, 0 @ invalidate I cache
mcr p15, 0, ip, c7, c10, 4 @ drain WB
mov pc, lr
__fa526_cache_flush:
tst r4, #1
movne pc, lr
mov r1, #0
mcr p15, 0, r1, c7, c14, 0 @ clean and invalidate D cache
mcr p15, 0, r1, c7, c5, 0 @ flush I cache
mcr p15, 0, r1, c7, c10, 4 @ drain WB
mov pc, lr
__armv6_mmu_cache_flush:
mov r1, #0
tst r4, #1
mcreq p15, 0, r1, c7, c14, 0 @ clean+invalidate D
mcr p15, 0, r1, c7, c5, 0 @ invalidate I+BTB
mcreq p15, 0, r1, c7, c15, 0 @ clean+invalidate unified
mcr p15, 0, r1, c7, c10, 4 @ drain WB
mov pc, lr
__armv7_mmu_cache_flush:
tst r4, #1
bne iflush
mrc p15, 0, r10, c0, c1, 5 @ read ID_MMFR1
tst r10, #0xf << 16 @ hierarchical cache (ARMv7)
mov r10, #0
beq hierarchical
mcr p15, 0, r10, c7, c14, 0 @ clean+invalidate D
b iflush
hierarchical:
mcr p15, 0, r10, c7, c10, 5 @ DMB
stmfd sp!, {r0-r7, r9-r11}
mrc p15, 1, r0, c0, c0, 1 @ read clidr
ands r3, r0, #0x7000000 @ extract loc from clidr
mov r3, r3, lsr #23 @ left align loc bit field
beq finished @ if loc is 0, then no need to clean
mov r10, #0 @ start clean at cache level 0
loop1:
add r2, r10, r10, lsr #1 @ work out 3x current cache level
mov r1, r0, lsr r2 @ extract cache type bits from clidr
and r1, r1, #7 @ mask of the bits for current cache only
cmp r1, #2 @ see what cache we have at this level
blt skip @ skip if no cache, or just i-cache
mcr p15, 2, r10, c0, c0, 0 @ select current cache level in cssr
mcr p15, 0, r10, c7, c5, 4 @ isb to sych the new cssr&csidr
mrc p15, 1, r1, c0, c0, 0 @ read the new csidr
and r2, r1, #7 @ extract the length of the cache lines
add r2, r2, #4 @ add 4 (line length offset)
ldr r4, =0x3ff
ands r4, r4, r1, lsr #3 @ find maximum number on the way size
clz r5, r4 @ find bit position of way size increment
ldr r7, =0x7fff
ands r7, r7, r1, lsr #13 @ extract max number of the index size
loop2:
mov r9, r4 @ create working copy of max way size
loop3:
ARM( orr r11, r10, r9, lsl r5 ) @ factor way and cache number into r11
ARM( orr r11, r11, r7, lsl r2 ) @ factor index number into r11
THUMB( lsl r6, r9, r5 )
THUMB( orr r11, r10, r6 ) @ factor way and cache number into r11
THUMB( lsl r6, r7, r2 )
THUMB( orr r11, r11, r6 ) @ factor index number into r11
mcr p15, 0, r11, c7, c14, 2 @ clean & invalidate by set/way
subs r9, r9, #1 @ decrement the way
bge loop3
subs r7, r7, #1 @ decrement the index
bge loop2
skip:
add r10, r10, #2 @ increment cache number
cmp r3, r10
bgt loop1
finished:
ldmfd sp!, {r0-r7, r9-r11}
mov r10, #0 @ swith back to cache level 0
mcr p15, 2, r10, c0, c0, 0 @ select current cache level in cssr
iflush:
mcr p15, 0, r10, c7, c10, 4 @ DSB
mcr p15, 0, r10, c7, c5, 0 @ invalidate I+BTB
mcr p15, 0, r10, c7, c10, 4 @ DSB
mcr p15, 0, r10, c7, c5, 4 @ ISB
mov pc, lr
__armv5tej_mmu_cache_flush:
tst r4, #1
movne pc, lr
1: mrc p15, 0, r15, c7, c14, 3 @ test,clean,invalidate D cache
bne 1b
mcr p15, 0, r0, c7, c5, 0 @ flush I cache
mcr p15, 0, r0, c7, c10, 4 @ drain WB
mov pc, lr
__armv4_mmu_cache_flush:
tst r4, #1
movne pc, lr
mov r2, #64*1024 @ default: 32K dcache size (*2)
mov r11, #32 @ default: 32 byte line size
mrc p15, 0, r3, c0, c0, 1 @ read cache type
teq r3, r9 @ cache ID register present?
beq no_cache_id
mov r1, r3, lsr #18
and r1, r1, #7
mov r2, #1024
mov r2, r2, lsl r1 @ base dcache size *2
tst r3, #1 << 14 @ test M bit
addne r2, r2, r2, lsr #1 @ +1/2 size if M == 1
mov r3, r3, lsr #12
and r3, r3, #3
mov r11, #8
mov r11, r11, lsl r3 @ cache line size in bytes
no_cache_id:
mov r1, pc
bic r1, r1, #63 @ align to longest cache line
add r2, r1, r2
1:
ARM( ldr r3, [r1], r11 ) @ s/w flush D cache
THUMB( ldr r3, [r1] ) @ s/w flush D cache
THUMB( add r1, r1, r11 )
teq r1, r2
bne 1b
mcr p15, 0, r1, c7, c5, 0 @ flush I cache
mcr p15, 0, r1, c7, c6, 0 @ flush D cache
mcr p15, 0, r1, c7, c10, 4 @ drain WB
mov pc, lr
__armv3_mmu_cache_flush:
__armv3_mpu_cache_flush:
tst r4, #1
movne pc, lr
mov r1, #0
mcr p15, 0, r1, c7, c0, 0 @ invalidate whole cache v3
mov pc, lr
/*
* Various debugging routines for printing hex characters and
* memory, which again must be relocatable.
*/
#ifdef DEBUG
.align 2
.type phexbuf,#object
phexbuf: .space 12
.size phexbuf, . - phexbuf
@ phex corrupts {r0, r1, r2, r3}
phex: adr r3, phexbuf
mov r2, #0
strb r2, [r3, r1]
1: subs r1, r1, #1
movmi r0, r3
bmi puts
and r2, r0, #15
mov r0, r0, lsr #4
cmp r2, #10
addge r2, r2, #7
add r2, r2, #'0'
strb r2, [r3, r1]
b 1b
@ puts corrupts {r0, r1, r2, r3}
puts: loadsp r3, r1
1: ldrb r2, [r0], #1
teq r2, #0
moveq pc, lr
2: writeb r2, r3
mov r1, #0x00020000
3: subs r1, r1, #1
bne 3b
teq r2, #'\n'
moveq r2, #'\r'
beq 2b
teq r0, #0
bne 1b
mov pc, lr
@ putc corrupts {r0, r1, r2, r3}
putc:
mov r2, r0
mov r0, #0
loadsp r3, r1
b 2b
@ memdump corrupts {r0, r1, r2, r3, r10, r11, r12, lr}
memdump: mov r12, r0
mov r10, lr
mov r11, #0
2: mov r0, r11, lsl #2
add r0, r0, r12
mov r1, #8
bl phex
mov r0, #':'
bl putc
1: mov r0, #' '
bl putc
ldr r0, [r12, r11, lsl #2]
mov r1, #8
bl phex
and r0, r11, #7
teq r0, #3
moveq r0, #' '
bleq putc
and r0, r11, #7
add r11, r11, #1
teq r0, #7
bne 1b
mov r0, #'\n'
bl putc
cmp r11, #64
blt 2b
mov pc, r10
#endif
.ltorg
#ifdef CONFIG_ARM_VIRT_EXT
.align 5
__hyp_reentry_vectors:
W(b) . @ reset
W(b) . @ undef
W(b) . @ svc
W(b) . @ pabort
W(b) . @ dabort
W(b) __enter_kernel @ hyp
W(b) . @ irq
W(b) . @ fiq
#endif /* CONFIG_ARM_VIRT_EXT */
__enter_kernel:
mov r0, #0 @ must be 0
ARM( mov pc, r4 ) @ call kernel
M_CLASS( add r4, r4, #1 ) @ enter in Thumb mode for M class
THUMB( bx r4 ) @ entry point is always ARM for A/R classes
reloc_code_end:
#ifdef CONFIG_EFI_STUB
.align 2
_start: .long start - .
ENTRY(efi_stub_entry)
@ allocate space on stack for passing current zImage address
@ and for the EFI stub to return of new entry point of
@ zImage, as EFI stub may copy the kernel. Pointer address
@ is passed in r2. r0 and r1 are passed through from the
@ EFI firmware to efi_entry
adr ip, _start
ldr r3, [ip]
add r3, r3, ip
stmfd sp!, {r3, lr}
mov r2, sp @ pass zImage address in r2
bl efi_entry
@ Check for error return from EFI stub. r0 has FDT address
@ or error code.
cmn r0, #1
beq efi_load_fail
@ Preserve return value of efi_entry() in r4
mov r4, r0
bl cache_clean_flush
bl cache_off
@ Set parameters for booting zImage according to boot protocol
@ put FDT address in r2, it was returned by efi_entry()
@ r1 is the machine type, and r0 needs to be 0
mov r0, #0
mov r1, #0xFFFFFFFF
mov r2, r4
@ Branch to (possibly) relocated zImage that is in [sp]
ldr lr, [sp]
ldr ip, =start_offset
add lr, lr, ip
mov pc, lr @ no mode switch
efi_load_fail:
@ Return EFI_LOAD_ERROR to EFI firmware on error.
ldr r0, =0x80000001
ldmfd sp!, {ip, pc}
ENDPROC(efi_stub_entry)
#endif
.align
.section ".stack", "aw", %nobits
.L_user_stack: .space 4096
.L_user_stack_end: