/*
* linux/arch/arm26/mm/proc-arm2,3.S
*
* Copyright (C) 1997-1999 Russell King
*
* 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.
*
* MMU functions for ARM2,3
*
* These are the low level assembler for performing cache
* and memory functions on ARM2, ARM250 and ARM3 processors.
*/
#include <linux/linkage.h>
#include <asm/assembler.h>
#include <asm/asm-offsets.h>
#include <asm/procinfo.h>
#include <asm/ptrace.h>
/*
* MEMC workhorse code. It's both a horse which things it's a pig.
*/
/*
* Function: cpu_memc_update_entry(pgd_t *pgd, unsigned long phys_pte, unsigned long addr)
* Params : pgd Page tables/MEMC mapping
* : phys_pte physical address, or PTE
* : addr virtual address
*/
ENTRY(cpu_memc_update_entry)
tst r1, #PAGE_PRESENT @ is the page present
orreq r1, r1, #PAGE_OLD | PAGE_CLEAN
moveq r2, #0x01f00000
mov r3, r1, lsr #13 @ convert to physical page nr
and r3, r3, #0x3fc
adr ip, memc_phys_table_32
ldr r3, [ip, r3]
tst r1, #PAGE_OLD | PAGE_NOT_USER
biceq r3, r3, #0x200
tsteq r1, #PAGE_READONLY | PAGE_CLEAN
biceq r3, r3, #0x300
mov r2, r2, lsr #15 @ virtual -> nr
orr r3, r3, r2, lsl #15
and r2, r2, #0x300
orr r3, r3, r2, lsl #2
and r2, r3, #255
sub r0, r0, #256 * 4
str r3, [r0, r2, lsl #2]
strb r3, [r3]
movs pc, lr
/*
* Params : r0 = preserved
* : r1 = memc table base (preserved)
* : r2 = page table entry
* : r3 = preserved
* : r4 = unused
* : r5 = memc physical address translation table
* : ip = virtual address (preserved)
*/
update_pte:
mov r4, r2, lsr #13
and r4, r4, #0x3fc
ldr r4, [r5, r4] @ covert to MEMC page
tst r2, #PAGE_OLD | PAGE_NOT_USER @ check for MEMC read
biceq r4, r4, #0x200
tsteq r2, #PAGE_READONLY | PAGE_CLEAN @ check for MEMC write
biceq r4, r4, #0x300
orr r4, r4, ip
and r2, ip, #0x01800000
orr r4, r4, r2, lsr #13
and r2, r4, #255
str r4, [r1, r2, lsl #2]
movs pc, lr
/*
* Params : r0 = preserved
* : r1 = memc table base (preserved)
* : r2 = page table base
* : r3 = preserved
* : r4 = unused
* : r5 = memc physical address translation table
* : ip = virtual address (updated)
*/
update_pte_table:
stmfd sp!, {r0, lr}
bic r0, r2, #3
1: ldr r2, [r0], #4 @ get entry
tst r2, #PAGE_PRESENT @ page present
blne update_pte @ process pte
add ip, ip, #32768 @ increment virt addr
ldr r2, [r0], #4 @ get entry
tst r2, #PAGE_PRESENT @ page present
blne update_pte @ process pte
add ip, ip, #32768 @ increment virt addr
ldr r2, [r0], #4 @ get entry
tst r2, #PAGE_PRESENT @ page present
blne update_pte @ process pte
add ip, ip, #32768 @ increment virt addr
ldr r2, [r0], #4 @ get entry
tst r2, #PAGE_PRESENT @ page present
blne update_pte @ process pte
add ip, ip, #32768 @ increment virt addr
tst ip, #32768 * 31 @ finished?
bne 1b
ldmfd sp!, {r0, pc}^
/*
* Function: cpu_memc_update_all(pgd_t *pgd)
* Params : pgd Page tables/MEMC mapping
* Notes : this is optimised for 32k pages
*/
ENTRY(cpu_memc_update_all)
stmfd sp!, {r4, r5, lr}
bl clear_tables
sub r1, r0, #256 * 4 @ start of MEMC tables
adr r5, memc_phys_table_32 @ Convert to logical page number
mov ip, #0 @ virtual address
1: ldmia r0!, {r2, r3} @ load two pgd entries
tst r2, #PAGE_PRESENT @ is pgd entry present?
addeq ip, ip, #1048576 @FIXME - PAGE_PRESENT is for PTEs technically...
blne update_pte_table
mov r2, r3
tst r2, #PAGE_PRESENT @ is pgd entry present?
addeq ip, ip, #1048576
blne update_pte_table
teq ip, #32 * 1048576
bne 1b
ldmfd sp!, {r4, r5, pc}^
/*
* Build the table to map from physical page number to memc page number
*/
.type memc_phys_table_32, #object
memc_phys_table_32:
.irp b7, 0x00, 0x80
.irp b6, 0x00, 0x02
.irp b5, 0x00, 0x04
.irp b4, 0x00, 0x01
.irp b3, 0x00, 0x40
.irp b2, 0x00, 0x20
.irp b1, 0x00, 0x10
.irp b0, 0x00, 0x08
.long 0x03800300 + \b7 + \b6 + \b5 + \b4 + \b3 + \b2 + \b1 + \b0
.endr
.endr
.endr
.endr
.endr
.endr
.endr
.endr
.size memc_phys_table_32, . - memc_phys_table_32
/*
* helper for cpu_memc_update_all, this clears out all
* mappings, setting them close to the top of memory,
* and inaccessible (0x01f00000).
* Params : r0 = page table pointer
*/
clear_tables: ldr r1, _arm3_set_pgd - 4
ldr r2, [r1]
sub r1, r0, #256 * 4 @ start of MEMC tables
add r2, r1, r2, lsl #2 @ end of tables
mov r3, #0x03f00000 @ Default mapping (null mapping)
orr r3, r3, #0x00000f00
orr r4, r3, #1
orr r5, r3, #2
orr ip, r3, #3
1: stmia r1!, {r3, r4, r5, ip}
add r3, r3, #4
add r4, r4, #4
add r5, r5, #4
add ip, ip, #4
stmia r1!, {r3, r4, r5, ip}
add r3, r3, #4
add r4, r4, #4
add r5, r5, #4
add ip, ip, #4
teq r1, r2
bne 1b
mov pc, lr
/*
* Function: *_set_pgd(pgd_t *pgd)
* Params : pgd New page tables/MEMC mapping
* Purpose : update MEMC hardware with new mapping
*/
.word page_nr @ extern - declared in mm-memc.c
_arm3_set_pgd: mcr p15, 0, r1, c1, c0, 0 @ flush cache
_arm2_set_pgd: stmfd sp!, {lr}
ldr r1, _arm3_set_pgd - 4
ldr r2, [r1]
sub r0, r0, #256 * 4 @ start of MEMC tables
add r1, r0, r2, lsl #2 @ end of tables
1: ldmia r0!, {r2, r3, ip, lr}
strb r2, [r2]
strb r3, [r3]
strb ip, [ip]
strb lr, [lr]
ldmia r0!, {r2, r3, ip, lr}
strb r2, [r2]
strb r3, [r3]
strb ip, [ip]
strb lr, [lr]
teq r0, r1
bne 1b
ldmfd sp!, {pc}^
/*
* Function: *_proc_init (void)
* Purpose : Initialise the cache control registers
*/
_arm3_proc_init:
mov r0, #0x001f0000
orr r0, r0, #0x0000ff00
orr r0, r0, #0x000000ff
mcr p15, 0, r0, c3, c0 @ ARM3 Cacheable
mcr p15, 0, r0, c4, c0 @ ARM3 Updateable
mov r0, #0
mcr p15, 0, r0, c5, c0 @ ARM3 Disruptive
mcr p15, 0, r0, c1, c0 @ ARM3 Flush
mov r0, #3
mcr p15, 0, r0, c2, c0 @ ARM3 Control
_arm2_proc_init:
movs pc, lr
/*
* Function: *_proc_fin (void)
* Purpose : Finalise processor (disable caches)
*/
_arm3_proc_fin: mov r0, #2
mcr p15, 0, r0, c2, c0
_arm2_proc_fin: orrs pc, lr, #PSR_I_BIT|PSR_F_BIT
/*
* Function: *_xchg_1 (int new, volatile void *ptr)
* Params : new New value to store at...
* : ptr pointer to byte-wide location
* Purpose : Performs an exchange operation
* Returns : Original byte data at 'ptr'
*/
_arm2_xchg_1: mov r2, pc
orr r2, r2, #PSR_I_BIT
teqp r2, #0
ldrb r2, [r1]
strb r0, [r1]
mov r0, r2
movs pc, lr
_arm3_xchg_1: swpb r0, r0, [r1]
movs pc, lr
/*
* Function: *_xchg_4 (int new, volatile void *ptr)
* Params : new New value to store at...
* : ptr pointer to word-wide location
* Purpose : Performs an exchange operation
* Returns : Original word data at 'ptr'
*/
_arm2_xchg_4: mov r2, pc
orr r2, r2, #PSR_I_BIT
teqp r2, #0
ldr r2, [r1]
str r0, [r1]
mov r0, r2
movs pc, lr
_arm3_xchg_4: swp r0, r0, [r1]
movs pc, lr
_arm2_3_check_bugs:
bics pc, lr, #PSR_F_BIT @ Clear FIQ disable bit
armvlsi_name: .asciz "ARM/VLSI"
_arm2_name: .asciz "ARM 2"
_arm250_name: .asciz "ARM 250"
_arm3_name: .asciz "ARM 3"
.section ".init.text", #alloc, #execinstr
/*
* Purpose : Function pointers used to access above functions - all calls
* come through these
*/
.globl arm2_processor_functions
arm2_processor_functions:
.word _arm2_3_check_bugs
.word _arm2_proc_init
.word _arm2_proc_fin
.word _arm2_set_pgd
.word _arm2_xchg_1
.word _arm2_xchg_4
cpu_arm2_info:
.long armvlsi_name
.long _arm2_name
.globl arm250_processor_functions
arm250_processor_functions:
.word _arm2_3_check_bugs
.word _arm2_proc_init
.word _arm2_proc_fin
.word _arm2_set_pgd
.word _arm3_xchg_1
.word _arm3_xchg_4
cpu_arm250_info:
.long armvlsi_name
.long _arm250_name
.globl arm3_processor_functions
arm3_processor_functions:
.word _arm2_3_check_bugs
.word _arm3_proc_init
.word _arm3_proc_fin
.word _arm3_set_pgd
.word _arm3_xchg_1
.word _arm3_xchg_4
cpu_arm3_info:
.long armvlsi_name
.long _arm3_name
arm2_arch_name: .asciz "armv1"
arm3_arch_name: .asciz "armv2"
arm2_elf_name: .asciz "v1"
arm3_elf_name: .asciz "v2"
.align
.section ".proc.info", #alloc, #execinstr
.long 0x41560200
.long 0xfffffff0
.long arm2_arch_name
.long arm2_elf_name
.long 0
.long cpu_arm2_info
.long arm2_processor_functions
.long 0x41560250
.long 0xfffffff0
.long arm3_arch_name
.long arm3_elf_name
.long 0
.long cpu_arm250_info
.long arm250_processor_functions
.long 0x41560300
.long 0xfffffff0
.long arm3_arch_name
.long arm3_elf_name
.long 0
.long cpu_arm3_info
.long arm3_processor_functions
