mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-23 20:53:53 +08:00
Automatic merge of kernel.org:/home/rmk/linux-2.6-rmk.git
This commit is contained in:
Linus Torvalds
commit
1e14c33fe2
@ -31,8 +31,3 @@ head-y := head.o
|
||||
obj-$(CONFIG_DEBUG_LL) += debug.o
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extra-y := $(head-y) init_task.o vmlinux.lds
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# Spell out some dependencies that aren't automatically figured out
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$(obj)/entry-armv.o: $(obj)/entry-header.S include/asm-arm/constants.h
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$(obj)/entry-common.o: $(obj)/entry-header.S include/asm-arm/constants.h \
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$(obj)/calls.S
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@ -64,6 +64,26 @@ int main(void)
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DEFINE(TI_VFPSTATE, offsetof(struct thread_info, vfpstate));
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DEFINE(TI_IWMMXT_STATE, (offsetof(struct thread_info, fpstate)+4)&~7);
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BLANK();
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DEFINE(S_R0, offsetof(struct pt_regs, ARM_r0));
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DEFINE(S_R1, offsetof(struct pt_regs, ARM_r1));
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DEFINE(S_R2, offsetof(struct pt_regs, ARM_r2));
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DEFINE(S_R3, offsetof(struct pt_regs, ARM_r3));
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DEFINE(S_R4, offsetof(struct pt_regs, ARM_r4));
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DEFINE(S_R5, offsetof(struct pt_regs, ARM_r5));
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DEFINE(S_R6, offsetof(struct pt_regs, ARM_r6));
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DEFINE(S_R7, offsetof(struct pt_regs, ARM_r7));
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DEFINE(S_R8, offsetof(struct pt_regs, ARM_r8));
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DEFINE(S_R9, offsetof(struct pt_regs, ARM_r9));
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DEFINE(S_R10, offsetof(struct pt_regs, ARM_r10));
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DEFINE(S_FP, offsetof(struct pt_regs, ARM_fp));
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DEFINE(S_IP, offsetof(struct pt_regs, ARM_ip));
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DEFINE(S_SP, offsetof(struct pt_regs, ARM_sp));
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DEFINE(S_LR, offsetof(struct pt_regs, ARM_lr));
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DEFINE(S_PC, offsetof(struct pt_regs, ARM_pc));
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DEFINE(S_PSR, offsetof(struct pt_regs, ARM_cpsr));
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DEFINE(S_OLD_R0, offsetof(struct pt_regs, ARM_ORIG_r0));
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DEFINE(S_FRAME_SIZE, sizeof(struct pt_regs));
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BLANK();
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#if __LINUX_ARM_ARCH__ >= 6
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DEFINE(MM_CONTEXT_ID, offsetof(struct mm_struct, context.id));
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BLANK();
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@ -14,12 +14,12 @@
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* it to save wrong values... Be aware!
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*/
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#include <linux/config.h>
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#include <linux/init.h>
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#include <asm/thread_info.h>
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#include <asm/glue.h>
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#include <asm/ptrace.h>
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#include <asm/vfpmacros.h>
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#include <asm/hardware.h> @ should be moved into entry-macro.S
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#include <asm/arch/irqs.h> @ should be moved into entry-macro.S
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#include <asm/arch/entry-macro.S>
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#include "entry-header.S"
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@ -118,7 +118,7 @@ __dabt_svc:
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@
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@ IRQs off again before pulling preserved data off the stack
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@
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disable_irq r0
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disable_irq
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@
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@ restore SPSR and restart the instruction
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@ -198,7 +198,7 @@ __und_svc:
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@
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@ IRQs off again before pulling preserved data off the stack
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@
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1: disable_irq r0
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1: disable_irq
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@
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@ restore SPSR and restart the instruction
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@ -232,7 +232,7 @@ __pabt_svc:
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@
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@ IRQs off again before pulling preserved data off the stack
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@
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disable_irq r0
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disable_irq
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@
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@ restore SPSR and restart the instruction
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@ -316,7 +316,7 @@ __dabt_usr:
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@
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@ IRQs on, then call the main handler
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@
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enable_irq r2
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enable_irq
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mov r2, sp
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adr lr, ret_from_exception
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b do_DataAbort
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@ -418,7 +418,7 @@ call_fpe:
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movcss r7, r5, lsr #(TIF_USING_IWMMXT + 1)
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bcs iwmmxt_task_enable
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#endif
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enable_irq r7
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enable_irq
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add pc, pc, r8, lsr #6
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mov r0, r0
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@ -472,7 +472,7 @@ fpundefinstr:
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__pabt_usr:
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usr_entry abt
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enable_irq r0 @ Enable interrupts
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enable_irq @ Enable interrupts
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mov r0, r2 @ address (pc)
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mov r1, sp @ regs
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bl do_PrefetchAbort @ call abort handler
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@ -522,8 +522,9 @@ ENTRY(__switch_to)
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/*
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* Vector stubs.
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*
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* This code is copied to 0x200 or 0xffff0200 so we can use branches in the
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* vectors, rather than ldr's.
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* This code is copied to 0xffff0200 so we can use branches in the
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* vectors, rather than ldr's. Note that this code must not
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* exceed 0x300 bytes.
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*
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* Common stub entry macro:
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* Enter in IRQ mode, spsr = SVC/USR CPSR, lr = SVC/USR PC
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@ -544,7 +545,7 @@ vector_\name:
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@
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mrs r13, cpsr
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bic r13, r13, #MODE_MASK
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orr r13, r13, #MODE_SVC
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orr r13, r13, #SVC_MODE
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msr spsr_cxsf, r13 @ switch to SVC_32 mode
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and lr, lr, #15
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@ -552,6 +553,7 @@ vector_\name:
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movs pc, lr @ Changes mode and branches
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.endm
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.globl __stubs_start
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__stubs_start:
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/*
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* Interrupt dispatcher
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@ -686,37 +688,24 @@ vector_addrexcptn:
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.LCsabt:
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.word __temp_abt
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.globl __stubs_end
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__stubs_end:
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.equ __real_stubs_start, .LCvectors + 0x200
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.equ stubs_offset, __vectors_start + 0x200 - __stubs_start
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.LCvectors:
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.globl __vectors_start
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__vectors_start:
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swi SYS_ERROR0
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b __real_stubs_start + (vector_und - __stubs_start)
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ldr pc, __real_stubs_start + (.LCvswi - __stubs_start)
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b __real_stubs_start + (vector_pabt - __stubs_start)
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b __real_stubs_start + (vector_dabt - __stubs_start)
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b __real_stubs_start + (vector_addrexcptn - __stubs_start)
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b __real_stubs_start + (vector_irq - __stubs_start)
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b __real_stubs_start + (vector_fiq - __stubs_start)
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b vector_und + stubs_offset
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ldr pc, .LCvswi + stubs_offset
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b vector_pabt + stubs_offset
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b vector_dabt + stubs_offset
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b vector_addrexcptn + stubs_offset
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b vector_irq + stubs_offset
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b vector_fiq + stubs_offset
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ENTRY(__trap_init)
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stmfd sp!, {r4 - r6, lr}
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mov r0, #0xff000000
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orr r0, r0, #0x00ff0000 @ high vectors position
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adr r1, .LCvectors @ set up the vectors
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ldmia r1, {r1, r2, r3, r4, r5, r6, ip, lr}
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stmia r0, {r1, r2, r3, r4, r5, r6, ip, lr}
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add r2, r0, #0x200
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adr r0, __stubs_start @ copy stubs to 0x200
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adr r1, __stubs_end
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1: ldr r3, [r0], #4
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str r3, [r2], #4
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cmp r0, r1
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blt 1b
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LOADREGS(fd, sp!, {r4 - r6, pc})
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.globl __vectors_end
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__vectors_end:
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.data
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@ -9,19 +9,10 @@
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*/
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#include <linux/config.h>
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#include <asm/thread_info.h>
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#include <asm/ptrace.h>
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#include <asm/unistd.h>
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#include "entry-header.S"
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/*
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* We rely on the fact that R0 is at the bottom of the stack (due to
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* slow/fast restore user regs).
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*/
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#if S_R0 != 0
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#error "Please fix"
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#endif
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.align 5
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/*
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@ -30,11 +21,19 @@
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* stack.
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*/
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ret_fast_syscall:
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disable_irq r1 @ disable interrupts
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disable_irq @ disable interrupts
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ldr r1, [tsk, #TI_FLAGS]
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tst r1, #_TIF_WORK_MASK
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bne fast_work_pending
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fast_restore_user_regs
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@ fast_restore_user_regs
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ldr r1, [sp, #S_OFF + S_PSR] @ get calling cpsr
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ldr lr, [sp, #S_OFF + S_PC]! @ get pc
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msr spsr_cxsf, r1 @ save in spsr_svc
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ldmdb sp, {r1 - lr}^ @ get calling r1 - lr
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mov r0, r0
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add sp, sp, #S_FRAME_SIZE - S_PC
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movs pc, lr @ return & move spsr_svc into cpsr
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/*
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* Ok, we need to do extra processing, enter the slow path.
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@ -49,7 +48,7 @@ work_pending:
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mov r0, sp @ 'regs'
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mov r2, why @ 'syscall'
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bl do_notify_resume
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disable_irq r1 @ disable interrupts
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disable_irq @ disable interrupts
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b no_work_pending
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work_resched:
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@ -59,12 +58,19 @@ work_resched:
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*/
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ENTRY(ret_to_user)
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ret_slow_syscall:
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disable_irq r1 @ disable interrupts
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disable_irq @ disable interrupts
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ldr r1, [tsk, #TI_FLAGS]
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tst r1, #_TIF_WORK_MASK
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bne work_pending
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no_work_pending:
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slow_restore_user_regs
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@ slow_restore_user_regs
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ldr r1, [sp, #S_PSR] @ get calling cpsr
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ldr lr, [sp, #S_PC]! @ get pc
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msr spsr_cxsf, r1 @ save in spsr_svc
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ldmdb sp, {r0 - lr}^ @ get calling r1 - lr
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mov r0, r0
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add sp, sp, #S_FRAME_SIZE - S_PC
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movs pc, lr @ return & move spsr_svc into cpsr
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/*
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* This is how we return from a fork.
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@ -116,9 +122,26 @@ ENTRY(ret_from_fork)
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.align 5
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ENTRY(vector_swi)
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save_user_regs
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sub sp, sp, #S_FRAME_SIZE
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stmia sp, {r0 - r12} @ Calling r0 - r12
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add r8, sp, #S_PC
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stmdb r8, {sp, lr}^ @ Calling sp, lr
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mrs r8, spsr @ called from non-FIQ mode, so ok.
|
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str lr, [sp, #S_PC] @ Save calling PC
|
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str r8, [sp, #S_PSR] @ Save CPSR
|
||||
str r0, [sp, #S_OLD_R0] @ Save OLD_R0
|
||||
zero_fp
|
||||
get_scno
|
||||
|
||||
/*
|
||||
* Get the system call number.
|
||||
*/
|
||||
#ifdef CONFIG_ARM_THUMB
|
||||
tst r8, #PSR_T_BIT @ this is SPSR from save_user_regs
|
||||
addne scno, r7, #__NR_SYSCALL_BASE @ put OS number in
|
||||
ldreq scno, [lr, #-4]
|
||||
#else
|
||||
ldr scno, [lr, #-4] @ get SWI instruction
|
||||
#endif
|
||||
arm710_bug_check scno, ip
|
||||
|
||||
#ifdef CONFIG_ALIGNMENT_TRAP
|
||||
@ -126,14 +149,14 @@ ENTRY(vector_swi)
|
||||
ldr ip, [ip]
|
||||
mcr p15, 0, ip, c1, c0 @ update control register
|
||||
#endif
|
||||
enable_irq ip
|
||||
enable_irq
|
||||
|
||||
str r4, [sp, #-S_OFF]! @ push fifth arg
|
||||
|
||||
get_thread_info tsk
|
||||
ldr ip, [tsk, #TI_FLAGS] @ check for syscall tracing
|
||||
bic scno, scno, #0xff000000 @ mask off SWI op-code
|
||||
eor scno, scno, #OS_NUMBER << 20 @ check OS number
|
||||
eor scno, scno, #__NR_SYSCALL_BASE @ check OS number
|
||||
adr tbl, sys_call_table @ load syscall table pointer
|
||||
tst ip, #_TIF_SYSCALL_TRACE @ are we tracing syscalls?
|
||||
bne __sys_trace
|
||||
@ -144,8 +167,8 @@ ENTRY(vector_swi)
|
||||
|
||||
add r1, sp, #S_OFF
|
||||
2: mov why, #0 @ no longer a real syscall
|
||||
cmp scno, #ARMSWI_OFFSET
|
||||
eor r0, scno, #OS_NUMBER << 20 @ put OS number back
|
||||
cmp scno, #(__ARM_NR_BASE - __NR_SYSCALL_BASE)
|
||||
eor r0, scno, #__NR_SYSCALL_BASE @ put OS number back
|
||||
bcs arm_syscall
|
||||
b sys_ni_syscall @ not private func
|
||||
|
||||
@ -190,7 +213,7 @@ ENTRY(sys_call_table)
|
||||
@ r5 = syscall table
|
||||
.type sys_syscall, #function
|
||||
sys_syscall:
|
||||
eor scno, r0, #OS_NUMBER << 20
|
||||
eor scno, r0, #__NR_SYSCALL_BASE
|
||||
cmp scno, #__NR_syscall - __NR_SYSCALL_BASE
|
||||
cmpne scno, #NR_syscalls @ check range
|
||||
stmloia sp, {r5, r6} @ shuffle args
|
||||
|
||||
@ -1,24 +1,11 @@
|
||||
#include <linux/config.h> /* for CONFIG_ARCH_xxxx */
|
||||
#include <linux/config.h>
|
||||
#include <linux/init.h>
|
||||
#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
|
||||
#include <asm/thread_info.h>
|
||||
|
||||
@ Bad Abort numbers
|
||||
@ -----------------
|
||||
@ -29,113 +16,44 @@
|
||||
#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.
|
||||
@
|
||||
@ Stack format (ensured by USER_* and SVC_*)
|
||||
@
|
||||
#define S_FRAME_SIZE 72
|
||||
#define S_OLD_R0 68
|
||||
#define S_PSR 64
|
||||
|
||||
#define S_PC 60
|
||||
#define S_LR 56
|
||||
#define S_SP 52
|
||||
#define S_IP 48
|
||||
#define S_FP 44
|
||||
#define S_R10 40
|
||||
#define S_R9 36
|
||||
#define S_R8 32
|
||||
#define S_R7 28
|
||||
#define S_R6 24
|
||||
#define S_R5 20
|
||||
#define S_R4 16
|
||||
#define S_R3 12
|
||||
#define S_R2 8
|
||||
#define S_R1 4
|
||||
#define S_R0 0
|
||||
#define S_OFF 8
|
||||
|
||||
.macro set_cpsr_c, reg, mode
|
||||
msr cpsr_c, \mode
|
||||
/*
|
||||
* 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
|
||||
|
||||
.macro zero_fp
|
||||
#ifdef CONFIG_FRAME_POINTER
|
||||
mov fp, #0
|
||||
#endif
|
||||
.endm
|
||||
|
||||
#if __LINUX_ARM_ARCH__ >= 6
|
||||
.macro disable_irq, temp
|
||||
.macro disable_irq
|
||||
cpsid i
|
||||
.endm
|
||||
|
||||
.macro enable_irq, temp
|
||||
.macro enable_irq
|
||||
cpsie i
|
||||
.endm
|
||||
#else
|
||||
.macro disable_irq, temp
|
||||
set_cpsr_c \temp, #PSR_I_BIT | MODE_SVC
|
||||
.macro disable_irq
|
||||
msr cpsr_c, #PSR_I_BIT | SVC_MODE
|
||||
.endm
|
||||
|
||||
.macro enable_irq, temp
|
||||
set_cpsr_c \temp, #MODE_SVC
|
||||
.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
|
||||
@ -165,18 +83,3 @@ 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
|
||||
|
||||
@ -578,9 +578,16 @@ EXPORT_SYMBOL(abort);
|
||||
|
||||
void __init trap_init(void)
|
||||
{
|
||||
extern void __trap_init(void);
|
||||
extern char __stubs_start[], __stubs_end[];
|
||||
extern char __vectors_start[], __vectors_end[];
|
||||
|
||||
__trap_init();
|
||||
/*
|
||||
* Copy the vectors and stubs (in entry-armv.S) into the
|
||||
* vector page, mapped at 0xffff0000, and ensure these are
|
||||
* visible to the instruction stream.
|
||||
*/
|
||||
memcpy((void *)0xffff0000, __vectors_start, __vectors_end - __vectors_start);
|
||||
memcpy((void *)0xffff0200, __stubs_start, __stubs_end - __stubs_start);
|
||||
flush_icache_range(0xffff0000, 0xffff0000 + PAGE_SIZE);
|
||||
modify_domain(DOMAIN_USER, DOMAIN_CLIENT);
|
||||
}
|
||||
|
||||
Loading…
Reference in New Issue
Block a user