proc-v6.S
/*
* linux/arch/arm/mm/proc-v6.S
*
* Copyright (C) 2001 Deep Blue Solutions Ltd.
*
* 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.
*
* This is the "shell" of the ARMv6 processor support.
*/
#include <linux/linkage.h>
#include <asm/assembler.h>
#include <asm/constants.h>
#include <asm/procinfo.h>
#include <asm/pgtable.h>
#include "proc-macros.S"
#define D_CACHE_LINE_SIZE 32
.macro cpsie, flags
.ifc \flags, f
.long 0xf1080040
.exitm
.endif
.ifc \flags, i
.long 0xf1080080
.exitm
.endif
.ifc \flags, if
.long 0xf10800c0
.exitm
.endif
.err
.endm
.macro cpsid, flags
.ifc \flags, f
.long 0xf10c0040
.exitm
.endif
.ifc \flags, i
.long 0xf10c0080
.exitm
.endif
.ifc \flags, if
.long 0xf10c00c0
.exitm
.endif
.err
.endm
ENTRY(cpu_v6_proc_init)
mov pc, lr
ENTRY(cpu_v6_proc_fin)
mov pc, lr
/*
* cpu_v6_reset(loc)
*
* Perform a soft reset of the system. Put the CPU into the
* same state as it would be if it had been reset, and branch
* to what would be the reset vector.
*
* - loc - location to jump to for soft reset
*
* It is assumed that:
*/
.align 5
ENTRY(cpu_v6_reset)
mov pc, r0
/*
* cpu_v6_do_idle()
*
* Idle the processor (eg, wait for interrupt).
*
* IRQs are already disabled.
*/
ENTRY(cpu_v6_do_idle)
mcr p15, 0, r1, c7, c0, 4 @ wait for interrupt
mov pc, lr
ENTRY(cpu_v6_dcache_clean_area)
#ifndef TLB_CAN_READ_FROM_L1_CACHE
1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
add r0, r0, #D_CACHE_LINE_SIZE
subs r1, r1, #D_CACHE_LINE_SIZE
bhi 1b
#endif
mov pc, lr
/*
* cpu_arm926_switch_mm(pgd_phys, tsk)
*
* Set the translation table base pointer to be pgd_phys
*
* - pgd_phys - physical address of new TTB
*
* It is assumed that:
* - we are not using split page tables
*/
ENTRY(cpu_v6_switch_mm)
mov r2, #0
ldr r1, [r1, #MM_CONTEXT_ID] @ get mm->context.id
mcr p15, 0, r2, c7, c5, 6 @ flush BTAC/BTB
mcr p15, 0, r2, c7, c10, 4 @ drain write buffer
mcr p15, 0, r0, c2, c0, 0 @ set TTB 0
mcr p15, 0, r1, c13, c0, 1 @ set context ID
mov pc, lr
#define nG (1 << 11)
#define APX (1 << 9)
#define AP1 (1 << 5)
#define AP0 (1 << 4)
#define XN (1 << 0)
/*
* cpu_v6_set_pte(ptep, pte)
*
* Set a level 2 translation table entry.
*
* - ptep - pointer to level 2 translation table entry
* (hardware version is stored at -1024 bytes)
* - pte - PTE value to store
*
* Permissions:
* YUWD APX AP1 AP0 SVC User
* 0xxx 0 0 0 no acc no acc
* 100x 1 0 1 r/o no acc
* 10x0 1 0 1 r/o no acc
* 1011 0 0 1 r/w no acc
* 110x 0 1 0 r/w r/o
* 11x0 0 1 0 r/w r/o
* 1111 0 1 1 r/w r/w
*/
ENTRY(cpu_v6_set_pte)
str r1, [r0], #-2048 @ linux version
bic r2, r1, #0x00000ff0
bic r2, r2, #0x00000003
orr r2, r2, #AP0 | 2
tst r1, #L_PTE_WRITE
tstne r1, #L_PTE_DIRTY
orreq r2, r2, #APX
tst r1, #L_PTE_USER
orrne r2, r2, #AP1 | nG
tstne r2, #APX
bicne r2, r2, #APX | AP0
tst r1, #L_PTE_YOUNG
biceq r2, r2, #APX | AP1 | AP0
@ tst r1, #L_PTE_EXEC
@ orreq r2, r2, #XN
tst r1, #L_PTE_PRESENT
moveq r2, #0
str r2, [r0]
mcr p15, 0, r0, c7, c10, 1 @ flush_pte
mov pc, lr
cpu_v6_name:
.asciz "Some Random V6 Processor"
.align
.section ".text.init", #alloc, #execinstr
/*
* __v6_setup
*
* Initialise TLB, Caches, and MMU state ready to switch the MMU
* on. Return in r0 the new CP15 C1 control register setting.
*
* We automatically detect if we have a Harvard cache, and use the
* Harvard cache control instructions insead of the unified cache
* control instructions.
*
* This should be able to cover all ARMv6 cores.
*
* It is assumed that:
* - cache type register is implemented
*/
__v6_setup:
mov r0, #0
mcr p15, 0, r0, c7, c14, 0 @ clean+invalidate D cache
mcr p15, 0, r0, c7, c5, 0 @ invalidate I cache
mcr p15, 0, r0, c7, c15, 0 @ clean+invalidate cache
mcr p15, 0, r0, c7, c10, 4 @ drain write buffer
mcr p15, 0, r0, c8, c7, 0 @ invalidate I + D TLBs
mcr p15, 0, r0, c2, c0, 2 @ TTB control register
mcr p15, 0, r4, c2, c0, 1 @ load TTB1
#ifdef CONFIG_VFP
mrc p15, 0, r0, c1, c0, 2
orr r0, r0, #(0xf << 20)
mcr p15, 0, r0, c1, c0, 2 @ Enable full access to VFP
#endif
mrc p15, 0, r0, c1, c0, 0 @ read control register
ldr r5, v6_cr1_clear @ get mask for bits to clear
bic r0, r0, r5 @ clear bits them
ldr r5, v6_cr1_set @ get mask for bits to set
orr r0, r0, r5 @ set them
mov pc, lr @ return to head.S:__ret
/*
* V X F I D LR
* .... ...E PUI. .T.T 4RVI ZFRS BLDP WCAM
* rrrr rrrx xxx0 0101 xxxx xxxx x111 xxxx < forced
* 0 110 0011 1.00 .111 1101 < we want
*/
.type v6_cr1_clear, #object
.type v6_cr1_set, #object
v6_cr1_clear:
.word 0x01e0fb7f
v6_cr1_set:
.word 0x00c0387d
.type v6_processor_functions, #object
ENTRY(v6_processor_functions)
.word v6_early_abort
.word cpu_v6_proc_init
.word cpu_v6_proc_fin
.word cpu_v6_reset
.word cpu_v6_do_idle
.word cpu_v6_dcache_clean_area
.word cpu_v6_switch_mm
.word cpu_v6_set_pte
.size v6_processor_functions, . - v6_processor_functions
.type cpu_arch_name, #object
cpu_arch_name:
.asciz "armv6"
.size cpu_arch_name, . - cpu_arch_name
.type cpu_elf_name, #object
cpu_elf_name:
.asciz "v6"
.size cpu_elf_name, . - cpu_elf_name
.align
.section ".proc.info", #alloc, #execinstr
/*
* Match any ARMv6 processor core.
*/
.type __v6_proc_info, #object
__v6_proc_info:
.long 0x0007b000
.long 0x0007f000
.long PMD_TYPE_SECT | \
PMD_SECT_BUFFERABLE | \
PMD_SECT_CACHEABLE | \
PMD_SECT_AP_WRITE | \
PMD_SECT_AP_READ
b __v6_setup
.long cpu_arch_name
.long cpu_elf_name
.long HWCAP_SWP|HWCAP_HALF|HWCAP_THUMB|HWCAP_FAST_MULT|HWCAP_VFP|HWCAP_EDSP|HWCAP_JAVA
.long cpu_v6_name
.long v6_processor_functions
.long v6wbi_tlb_fns
.long v6_user_fns
.long v6_cache_fns
.size __v6_proc_info, . - __v6_proc_info
