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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/arm/kernel/entry-header.S
downloadlinux-linaro-stable-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'arch/arm/kernel/entry-header.S')
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diff --git a/arch/arm/kernel/entry-header.S b/arch/arm/kernel/entry-header.S
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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
+
+@
+@ 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
+ .endm
+
+#if __LINUX_ARM_ARCH__ >= 6
+ .macro disable_irq, temp
+ cpsid i
+ .endm
+
+ .macro enable_irq, temp
+ cpsie i
+ .endm
+#else
+ .macro disable_irq, temp
+ set_cpsr_c \temp, #PSR_I_BIT | MODE_SVC
+ .endm
+
+ .macro enable_irq, temp
+ set_cpsr_c \temp, #MODE_SVC
+ .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