1 files changed, 182 insertions, 0 deletions

diff --git a/arch/arm/kernel/entry-header.S b/arch/arm/kernel/entry-header.S
new file mode 100644
index 000000000000..4039d8c120b5
--- /dev/null
+++ b/arch/arm/kernel/entry-header.S
@@ -0,0 +1,182 @@
+#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