kernel-ark/arch/arm/mm/proc-v6.S
Russell King 6626a7076d [ARM] Control v6 'global' bit via Linux PTE entries
Unfortunately, we can't use the "user" bit in the page tables to
control whether a page table entry is "global" or "asid" specific,
since the vector page is mapped as "user" accessible but is not
process specific.

Therefore, give direct control of the ARMv6 "nG" (not global)
bit to the mm layers.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-08-10 16:18:35 +01:00

267 lines
5.8 KiB
ArmAsm

/*
* 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
/*
* 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, #0x000007f0
bic r2, r2, #0x00000003
orr r2, r2, #PTE_EXT_AP0 | 2
tst r1, #L_PTE_WRITE
tstne r1, #L_PTE_DIRTY
orreq r2, r2, #PTE_EXT_APX
tst r1, #L_PTE_USER
orrne r2, r2, #PTE_EXT_AP1
tstne r2, #PTE_EXT_APX
bicne r2, r2, #PTE_EXT_APX | PTE_EXT_AP0
tst r1, #L_PTE_YOUNG
biceq r2, r2, #PTE_EXT_APX | PTE_EXT_AP_MASK
@ tst r1, #L_PTE_EXEC
@ orreq r2, r2, #PTE_EXT_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