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#include <linux/config.h> /* for CONFIG_ARCH_xxxx */
#include <linux/linkage.h>
#include <asm/assembler.h>
#include <asm/constants.h>
#include <asm/errno.h>
#include <asm/hardware.h>
#include <asm/arch/irqs.h>
#include <asm/arch/entry-macro.S>
#ifndef MODE_SVC
#define MODE_SVC 0x13
#endif
.macro zero_fp
#ifdef CONFIG_FRAME_POINTER
mov fp, #0
#endif
.endm
.text
@ Bad Abort numbers
@ -----------------
@
#define BAD_PREFETCH 0
#define BAD_DATA 1
#define BAD_ADDREXCPTN 2
#define BAD_IRQ 3
#define BAD_UNDEFINSTR 4
#define PT_TRACESYS 0x00000002
@ OS version number used in SWIs
@ RISC OS is 0
@ RISC iX is 8
@
#define OS_NUMBER 9
#define ARMSWI_OFFSET 0x000f0000
@
@ Most of the stack format comes from struct pt_regs, but with
@ the addition of 8 bytes for storing syscall args 5 and 6.
@
#define S_OFF 8
/*
* The SWI code relies on the fact that R0 is at the bottom of the stack
* (due to slow/fast restore user regs).
*/
#if S_R0 != 0
#error "Please fix"
#endif
#if __LINUX_ARM_ARCH__ >= 6
.macro disable_irq
cpsid i
.endm
.macro enable_irq
cpsie i
.endm
#else
.macro disable_irq
msr cpsr_c, #PSR_I_BIT | SVC_MODE
.endm
.macro enable_irq
msr cpsr_c, #SVC_MODE
.endm
#endif
.macro save_user_regs
sub sp, sp, #S_FRAME_SIZE
stmia sp, {r0 - r12} @ Calling r0 - r12
add r8, sp, #S_PC
stmdb r8, {sp, lr}^ @ Calling sp, lr
mrs r8, spsr @ called from non-FIQ mode, so ok.
str lr, [sp, #S_PC] @ Save calling PC
str r8, [sp, #S_PSR] @ Save CPSR
str r0, [sp, #S_OLD_R0] @ Save OLD_R0
.endm
.macro restore_user_regs
ldr r1, [sp, #S_PSR] @ Get calling cpsr
disable_irq ip @ disable IRQs
ldr lr, [sp, #S_PC]! @ Get PC
msr spsr_cxsf, r1 @ save in spsr_svc
ldmdb sp, {r0 - lr}^ @ Get calling r0 - lr
mov r0, r0
add sp, sp, #S_FRAME_SIZE - S_PC
movs pc, lr @ return & move spsr_svc into cpsr
.endm
/*
* Must be called with IRQs already disabled.
*/
.macro fast_restore_user_regs
ldr r1, [sp, #S_OFF + S_PSR] @ get calling cpsr
ldr lr, [sp, #S_OFF + S_PC]! @ get pc
msr spsr_cxsf, r1 @ save in spsr_svc
ldmdb sp, {r1 - lr}^ @ get calling r1 - lr
mov r0, r0
add sp, sp, #S_FRAME_SIZE - S_PC
movs pc, lr @ return & move spsr_svc into cpsr
.endm
/*
* Must be called with IRQs already disabled.
*/
.macro slow_restore_user_regs
ldr r1, [sp, #S_PSR] @ get calling cpsr
ldr lr, [sp, #S_PC]! @ get pc
msr spsr_cxsf, r1 @ save in spsr_svc
ldmdb sp, {r0 - lr}^ @ get calling r1 - lr
mov r0, r0
add sp, sp, #S_FRAME_SIZE - S_PC
movs pc, lr @ return & move spsr_svc into cpsr
.endm
.macro mask_pc, rd, rm
.endm
.macro get_thread_info, rd
mov \rd, sp, lsr #13
mov \rd, \rd, lsl #13
.endm
.macro alignment_trap, rbase, rtemp, sym
#ifdef CONFIG_ALIGNMENT_TRAP
#define OFF_CR_ALIGNMENT(x) cr_alignment - x
ldr \rtemp, [\rbase, #OFF_CR_ALIGNMENT(\sym)]
mcr p15, 0, \rtemp, c1, c0
#endif
.endm
/*
* These are the registers used in the syscall handler, and allow us to
* have in theory up to 7 arguments to a function - r0 to r6.
*
* r7 is reserved for the system call number for thumb mode.
*
* Note that tbl == why is intentional.
*
* We must set at least "tsk" and "why" when calling ret_with_reschedule.
*/
scno .req r7 @ syscall number
tbl .req r8 @ syscall table pointer
why .req r8 @ Linux syscall (!= 0)
tsk .req r9 @ current thread_info
/*
* Get the system call number.
*/
.macro get_scno
#ifdef CONFIG_ARM_THUMB
tst r8, #PSR_T_BIT @ this is SPSR from save_user_regs
addne scno, r7, #OS_NUMBER << 20 @ put OS number in
ldreq scno, [lr, #-4]
#else
mask_pc lr, lr
ldr scno, [lr, #-4] @ get SWI instruction
#endif
.endm
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