[PATCH 55/58] microblaze_v5: entry.S

From: monstr
Date: Tue Jul 08 2008 - 08:07:36 EST


From: Michal Simek <monstr@xxxxxxxxx>

Acked-by: Stephen Neuendorffer <stephen.neuendorffer@xxxxxxxxxx>
Signed-off-by: Michal Simek <monstr@xxxxxxxxx>
---
arch/microblaze/kernel/entry.S | 597 ++++++++++++++++++++++++++++++++++++++++
1 files changed, 597 insertions(+), 0 deletions(-)
create mode 100644 arch/microblaze/kernel/entry.S

diff --git a/arch/microblaze/kernel/entry.S b/arch/microblaze/kernel/entry.S
new file mode 100644
index 0000000..cfabea7
--- /dev/null
+++ b/arch/microblaze/kernel/entry.S
@@ -0,0 +1,597 @@
+/*
+ * arch/microblaze/kernel/entry.S
+ *
+ * Copyright (C) 2006 Atmark Techno, Inc.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#include <linux/linkage.h>
+#include <asm/thread_info.h>
+#include <asm/errno.h>
+#include <asm/asm-offsets.h>
+#include <asm/registers.h>
+#include <asm/unistd.h>
+#include <asm/percpu.h>
+#include <asm/signal.h>
+
+#define PER_CPU(var) per_cpu__##var
+
+#if CONFIG_XILINX_MICROBLAZE0_USE_MSR_INSTR
+ .macro disable_irq
+ msrclr r0, MSR_IE
+ .endm
+
+ .macro enable_irq
+ msrset r0, MSR_IE
+ .endm
+
+ .macro clear_bip
+ msrclr r0, MSR_BIP
+ .endm
+#else
+ .macro disable_irq
+ mfs r11, rmsr
+ andi r11, r11, ~MSR_IE
+ mts rmsr, r11
+ .endm
+
+ .macro enable_irq
+ mfs r11, rmsr
+ ori r11, r11, MSR_IE
+ mts rmsr, r11
+ .endm
+
+ .macro clear_bip
+ mfs r11, rmsr
+ andi r11, r11, ~MSR_BIP
+ mts rmsr, r11
+ .endm
+#endif
+
+ENTRY(_interrupt)
+ swi r1, r0, PER_CPU(ENTRY_SP) /* save the current sp */
+ swi r11, r0, PER_CPU(R11_SAVE) /* temporarily save r11 */
+ lwi r11, r0, PER_CPU(KM) /* load mode indicator */
+ beqid r11, 1f
+ nop
+ brid 2f /* jump over */
+ addik r1, r1, (-PT_SIZE) /* room for pt_regs (delay slot) */
+1: /* switch to kernel stack */
+ lwi r1, r0, PER_CPU(CURRENT_SAVE) /* get the saved current */
+ lwi r1, r1, TS_THREAD_INFO /* get the thread info */
+ /* calculate kernel stack pointer */
+ addik r1, r1, THREAD_SIZE - PT_SIZE
+2:
+ swi r11, r1, PT_MODE /* store the mode */
+ lwi r11, r0, PER_CPU(R11_SAVE) /* reload r11 */
+ swi r2, r1, PT_R2
+ swi r3, r1, PT_R3
+ swi r4, r1, PT_R4
+ swi r5, r1, PT_R5
+ swi r6, r1, PT_R6
+ swi r7, r1, PT_R7
+ swi r8, r1, PT_R8
+ swi r9, r1, PT_R9
+ swi r10, r1, PT_R10
+ swi r11, r1, PT_R11
+ swi r12, r1, PT_R12
+ swi r13, r1, PT_R13
+ swi r14, r1, PT_R14
+ swi r14, r1, PT_PC
+ swi r15, r1, PT_R15
+ swi r16, r1, PT_R16
+ swi r17, r1, PT_R17
+ swi r18, r1, PT_R18
+ swi r19, r1, PT_R19
+ swi r20, r1, PT_R20
+ swi r21, r1, PT_R21
+ swi r22, r1, PT_R22
+ swi r23, r1, PT_R23
+ swi r24, r1, PT_R24
+ swi r25, r1, PT_R25
+ swi r26, r1, PT_R26
+ swi r27, r1, PT_R27
+ swi r28, r1, PT_R28
+ swi r29, r1, PT_R29
+ swi r30, r1, PT_R30
+ swi r31, r1, PT_R31
+ /* special purpose registers */
+ mfs r11, rmsr
+ swi r11, r1, PT_MSR
+ mfs r11, rear
+ swi r11, r1, PT_EAR
+ mfs r11, resr
+ swi r11, r1, PT_ESR
+ mfs r11, rfsr
+ swi r11, r1, PT_FSR
+ /* reload original stack pointer and save it */
+ lwi r11, r0, PER_CPU(ENTRY_SP)
+ swi r11, r1, PT_R1
+ /* update mode indicator we are in kernel mode */
+ addik r11, r0, 1
+ swi r11, r0, PER_CPU(KM)
+ /* restore r31 */
+ lwi r31, r0, PER_CPU(CURRENT_SAVE)
+ /* prepare the link register, the argument and jump */
+ la r15, r0, ret_from_intr - 8
+ addk r6, r0, r15
+ braid do_IRQ
+ add r5, r0, r1
+
+ret_from_intr:
+ lwi r11, r1, PT_MODE
+ bneid r11, 3f
+
+ lwi r6, r31, TS_THREAD_INFO /* get thread info */
+ lwi r19, r6, TI_FLAGS /* get flags in thread info */
+ /* do an extra work if any bits are set */
+
+ andi r11, r19, _TIF_NEED_RESCHED
+ beqi r11, 1f
+ bralid r15, schedule
+ nop
+1: andi r11, r19, _TIF_SIGPENDING
+ beqid r11, no_intr_reshed
+ addk r5, r1, r0
+ addk r7, r0, r0
+ bralid r15, do_signal
+ addk r6, r0, r0
+
+no_intr_reshed:
+ /* save mode indicator */
+ lwi r11, r1, PT_MODE
+3:
+ swi r11, r0, PER_CPU(KM)
+
+ /* save r31 */
+ swi r31, r0, PER_CPU(CURRENT_SAVE)
+restore_context:
+ /* special purpose registers */
+ lwi r11, r1, PT_FSR
+ mts rfsr, r11
+ lwi r11, r1, PT_ESR
+ mts resr, r11
+ lwi r11, r1, PT_EAR
+ mts rear, r11
+ lwi r11, r1, PT_MSR
+ mts rmsr, r11
+
+ lwi r31, r1, PT_R31
+ lwi r30, r1, PT_R30
+ lwi r29, r1, PT_R29
+ lwi r28, r1, PT_R28
+ lwi r27, r1, PT_R27
+ lwi r26, r1, PT_R26
+ lwi r25, r1, PT_R25
+ lwi r24, r1, PT_R24
+ lwi r23, r1, PT_R23
+ lwi r22, r1, PT_R22
+ lwi r21, r1, PT_R21
+ lwi r20, r1, PT_R20
+ lwi r19, r1, PT_R19
+ lwi r18, r1, PT_R18
+ lwi r17, r1, PT_R17
+ lwi r16, r1, PT_R16
+ lwi r15, r1, PT_R15
+ lwi r14, r1, PT_PC
+ lwi r13, r1, PT_R13
+ lwi r12, r1, PT_R12
+ lwi r11, r1, PT_R11
+ lwi r10, r1, PT_R10
+ lwi r9, r1, PT_R9
+ lwi r8, r1, PT_R8
+ lwi r7, r1, PT_R7
+ lwi r6, r1, PT_R6
+ lwi r5, r1, PT_R5
+ lwi r4, r1, PT_R4
+ lwi r3, r1, PT_R3
+ lwi r2, r1, PT_R2
+ lwi r1, r1, PT_R1
+ rtid r14, 0
+ nop
+
+ENTRY(_reset)
+ brai 0;
+
+ENTRY(_user_exception)
+ swi r1, r0, PER_CPU(ENTRY_SP) /* save the current sp */
+ swi r11, r0, PER_CPU(R11_SAVE) /* temporarily save r11 */
+ lwi r11, r0, PER_CPU(KM) /* load mode indicator */
+ beqid r11, 1f /* Already in kernel mode? */
+ nop
+ brid 2f /* jump over */
+ addik r1, r1, (-PT_SIZE) /* Room for pt_regs (delay slot) */
+1: /* Switch to kernel stack */
+ lwi r1, r0, PER_CPU(CURRENT_SAVE) /* get the saved current */
+ lwi r1, r1, TS_THREAD_INFO /* get the thread info */
+ /* calculate kernel stack pointer */
+ addik r1, r1, THREAD_SIZE - PT_SIZE
+ swi r11, r0, PER_CPU(R11_SAVE) /* temporarily save r11 */
+ lwi r11, r0, PER_CPU(KM) /* load mode indicator */
+2:
+ swi r11, r1, PT_MODE /* store the mode */
+ lwi r11, r0, PER_CPU(R11_SAVE) /* reload r11 */
+ /* save them on stack */
+ swi r2, r1, PT_R2
+ swi r3, r1, PT_R3 /* r3: _always_ in clobber list; see unistd.h */
+ swi r4, r1, PT_R4 /* r4: _always_ in clobber list; see unistd.h */
+ swi r5, r1, PT_R5
+ swi r6, r1, PT_R6
+ swi r7, r1, PT_R7
+ swi r8, r1, PT_R8
+ swi r9, r1, PT_R9
+ swi r10, r1, PT_R10
+ swi r11, r1, PT_R11
+ /* r12: _always_ in clobber list; see unistd.h */
+ swi r12, r1, PT_R12
+ swi r13, r1, PT_R13
+ /* r14: _always_ in clobber list; see unistd.h */
+ swi r14, r1, PT_R14
+ /* but we want to return to the next inst. */
+ addik r14, r14, 0x4
+ swi r14, r1, PT_PC /* increment by 4 and store in pc */
+ swi r15, r1, PT_R15
+ swi r16, r1, PT_R16
+ swi r17, r1, PT_R17
+ swi r18, r1, PT_R18
+ swi r19, r1, PT_R19
+ swi r20, r1, PT_R20
+ swi r21, r1, PT_R21
+ swi r22, r1, PT_R22
+ swi r23, r1, PT_R23
+ swi r24, r1, PT_R24
+ swi r25, r1, PT_R25
+ swi r26, r1, PT_R26
+ swi r27, r1, PT_R27
+ swi r28, r1, PT_R28
+ swi r29, r1, PT_R29
+ swi r30, r1, PT_R30
+ swi r31, r1, PT_R31
+
+ disable_irq
+ nop /* make sure IE bit is in effect */
+ clear_bip /* once IE is in effect it is safe to clear BIP */
+ nop
+
+ /* special purpose registers */
+ mfs r11, rmsr
+ swi r11, r1, PT_MSR
+ mfs r11, rear
+ swi r11, r1, PT_EAR
+ mfs r11, resr
+ swi r11, r1, PT_ESR
+ mfs r11, rfsr
+ swi r11, r1, PT_FSR
+ /* reload original stack pointer and save it */
+ lwi r11, r0, PER_CPU(ENTRY_SP)
+ swi r11, r1, PT_R1
+ /* update mode indicator we are in kernel mode */
+ addik r11, r0, 1
+ swi r11, r0, PER_CPU(KM)
+ /* restore r31 */
+ lwi r31, r0, PER_CPU(CURRENT_SAVE)
+ /* re-enable interrupts now we are in kernel mode */
+ enable_irq
+
+ /* See if the system call number is valid. */
+ addi r11, r12, -NR_syscalls
+ bgei r11, 1f /* return to user if not valid */
+ /* Figure out which function to use for this system call. */
+ /* Note Microblaze barrel shift is optional, so don't rely on it */
+ add r12, r12, r12 /* convert num -> ptr */
+ add r12, r12, r12
+ lwi r12, r12, sys_call_table /* Get function pointer */
+ la r15, r0, ret_to_user-8 /* set return address */
+ bra r12 /* Make the system call. */
+ bri 0 /* won't reach here */
+1:
+ brid ret_to_user /* jump to syscall epilogue */
+ addi r3, r0, -ENOSYS /* set errno in delay slot */
+
+/*
+ * Debug traps are like a system call, but entered via brki r14, 0x60
+ * All we need to do is send the SIGTRAP signal to current, ptrace and do_signal
+ * will handle the rest
+ */
+ENTRY(_debug_exception)
+ swi r1, r0, PER_CPU(ENTRY_SP) /* save the current sp */
+ lwi r1, r0, PER_CPU(CURRENT_SAVE) /* get the saved current */
+ lwi r1, r1, TS_THREAD_INFO /* get the thread info */
+ addik r1, r1, THREAD_SIZE - PT_SIZE /* get the kernel stack */
+ swi r11, r0, PER_CPU(R11_SAVE) /* temporarily save r11 */
+ lwi r11, r0, PER_CPU(KM) /* load mode indicator */
+//save_context:
+ swi r11, r1, PT_MODE /* store the mode */
+ lwi r11, r0, PER_CPU(R11_SAVE) /* reload r11 */
+ /* save them on stack */
+ swi r2, r1, PT_R2
+ swi r3, r1, PT_R3 /* r3: _always_ in clobber list; see unistd.h */
+ swi r4, r1, PT_R4 /* r4: _always_ in clobber list; see unistd.h */
+ swi r5, r1, PT_R5
+ swi r6, r1, PT_R6
+ swi r7, r1, PT_R7
+ swi r8, r1, PT_R8
+ swi r9, r1, PT_R9
+ swi r10, r1, PT_R10
+ swi r11, r1, PT_R11
+ /* r12: _always_ in clobber list; see unistd.h */
+ swi r12, r1, PT_R12
+ swi r13, r1, PT_R13
+ /* r14: _always_ in clobber list; see unistd.h */
+ swi r14, r1, PT_R14
+ swi r14, r1, PT_PC /* Will return to interrupted instruction */
+ swi r15, r1, PT_R15
+ swi r16, r1, PT_R16
+ swi r17, r1, PT_R17
+ swi r18, r1, PT_R18
+ swi r19, r1, PT_R19
+ swi r20, r1, PT_R20
+ swi r21, r1, PT_R21
+ swi r22, r1, PT_R22
+ swi r23, r1, PT_R23
+ swi r24, r1, PT_R24
+ swi r25, r1, PT_R25
+ swi r26, r1, PT_R26
+ swi r27, r1, PT_R27
+ swi r28, r1, PT_R28
+ swi r29, r1, PT_R29
+ swi r30, r1, PT_R30
+ swi r31, r1, PT_R31
+
+ disable_irq
+ nop /* make sure IE bit is in effect */
+ clear_bip /* once IE is in effect it is safe to clear BIP */
+ nop
+
+ /* special purpose registers */
+ mfs r11, rmsr
+ swi r11, r1, PT_MSR
+ mfs r11, rear
+ swi r11, r1, PT_EAR
+ mfs r11, resr
+ swi r11, r1, PT_ESR
+ mfs r11, rfsr
+ swi r11, r1, PT_FSR
+ /* reload original stack pointer and save it */
+ lwi r11, r0, PER_CPU(ENTRY_SP)
+ swi r11, r1, PT_R1
+ /* update mode indicator we are in kernel mode */
+ addik r11, r0, 1
+ swi r11, r0, PER_CPU(KM)
+ /* restore r31 */
+ lwi r31, r0, PER_CPU(CURRENT_SAVE)
+ /* re-enable interrupts now we are in kernel mode */
+ enable_irq
+
+ addi r5, r0, SIGTRAP /* sending the trap signal */
+ add r6, r0, r31 /* to current */
+ bralid r15, send_sig
+ add r7, r0, r0 /* 3rd param zero */
+
+ /* Restore r3/r4 to work around how ret_to_user works */
+ lwi r3, r1, PT_R3
+ lwi r4, r1, PT_R4
+ bri ret_to_user
+
+ENTRY(_break)
+ bri 0
+
+/* struct task_struct *_switch_to(struct thread_info *prev,
+ struct thread_info *next); */
+ENTRY(_switch_to)
+ /* prepare return value */
+ addk r3, r0, r31
+
+ /* save registers in cpu_context */
+ /* use r11 and r12, volatile registers, as temp register */
+ addik r11, r5, TI_CPU_CONTEXT
+ swi r1, r11, CC_SP
+ swi r2, r11, CC_R2
+ /* skip volatile registers.
+ * they are saved on stack when we jumped to _switch_to() */
+ /* dedicated registers */
+ swi r13, r11, CC_R13
+ swi r14, r11, CC_R14
+ swi r15, r11, CC_R15
+ swi r16, r11, CC_R16
+ swi r17, r11, CC_R17
+ swi r18, r11, CC_R18
+ /* save non-volatile registers */
+ swi r19, r11, CC_R19
+ swi r20, r11, CC_R20
+ swi r21, r11, CC_R21
+ swi r22, r11, CC_R22
+ swi r23, r11, CC_R23
+ swi r24, r11, CC_R24
+ swi r25, r11, CC_R25
+ swi r26, r11, CC_R26
+ swi r27, r11, CC_R27
+ swi r28, r11, CC_R28
+ swi r29, r11, CC_R29
+ swi r30, r11, CC_R30
+ /* special purpose registers */
+ mfs r12, rmsr
+ swi r12, r11, CC_MSR
+ mfs r12, rear
+ swi r12, r11, CC_EAR
+ mfs r12, resr
+ swi r12, r11, CC_ESR
+ mfs r12, rfsr
+ swi r12, r11, CC_FSR
+
+ /* update r31, the current */
+ lwi r31, r6, TI_TASK
+ swi r31, r0, PER_CPU(CURRENT_SAVE)
+
+ /* get new process' cpu context and restore */
+ addik r11, r6, TI_CPU_CONTEXT
+
+ /* special purpose registers */
+ lwi r12, r11, CC_FSR
+ mts rfsr, r12
+ lwi r12, r11, CC_ESR
+ mts resr, r12
+ lwi r12, r11, CC_EAR
+ mts rear, r12
+ lwi r12, r11, CC_MSR
+ mts rmsr, r12
+ /* non-volatile registers */
+ lwi r30, r11, CC_R30
+ lwi r29, r11, CC_R29
+ lwi r28, r11, CC_R28
+ lwi r27, r11, CC_R27
+ lwi r26, r11, CC_R26
+ lwi r25, r11, CC_R25
+ lwi r24, r11, CC_R24
+ lwi r23, r11, CC_R23
+ lwi r22, r11, CC_R22
+ lwi r21, r11, CC_R21
+ lwi r20, r11, CC_R20
+ lwi r19, r11, CC_R19
+ /* dedicated registers */
+ lwi r18, r11, CC_R18
+ lwi r17, r11, CC_R17
+ lwi r16, r11, CC_R16
+ lwi r15, r11, CC_R15
+ lwi r14, r11, CC_R14
+ lwi r13, r11, CC_R13
+ /* skip volatile registers */
+ lwi r2, r11, CC_R2
+ lwi r1, r11, CC_SP
+
+ rtsd r15, 8
+ nop
+
+ENTRY(ret_from_fork)
+ addk r5, r0, r3
+ addk r6, r0, r1
+ brlid r15, schedule_tail
+ nop
+ swi r31, r1, PT_R31 /* save r31 in user context. */
+ /* will soon be restored to r31 in ret_to_user */
+ addk r3, r0, r0
+ brid ret_to_user
+ nop
+
+work_pending:
+ andi r11, r19, _TIF_NEED_RESCHED
+ beqi r11, 1f
+ bralid r15, schedule
+ nop
+1: andi r11, r19, _TIF_SIGPENDING
+ beqi r11, no_work_pending
+ addk r5, r1, r0
+ addik r7, r0, 1
+ bralid r15, do_signal
+ addk r6, r0, r0
+ bri no_work_pending
+
+ENTRY(ret_to_user)
+ disable_irq
+
+ swi r4, r1, PT_R4 /* return val */
+ swi r3, r1, PT_R3 /* return val */
+
+ lwi r6, r31, TS_THREAD_INFO /* get thread info */
+ lwi r19, r6, TI_FLAGS /* get flags in thread info */
+ bnei r19, work_pending /* do an extra work if any bits are set */
+no_work_pending:
+ disable_irq
+
+ /* save r31 */
+ swi r31, r0, PER_CPU(CURRENT_SAVE)
+ /* save mode indicator */
+ lwi r18, r1, PT_MODE
+ swi r18, r0, PER_CPU(KM)
+//restore_context:
+ /* special purpose registers */
+ lwi r18, r1, PT_FSR
+ mts rfsr, r18
+ lwi r18, r1, PT_ESR
+ mts resr, r18
+ lwi r18, r1, PT_EAR
+ mts rear, r18
+ lwi r18, r1, PT_MSR
+ mts rmsr, r18
+
+ lwi r31, r1, PT_R31
+ lwi r30, r1, PT_R30
+ lwi r29, r1, PT_R29
+ lwi r28, r1, PT_R28
+ lwi r27, r1, PT_R27
+ lwi r26, r1, PT_R26
+ lwi r25, r1, PT_R25
+ lwi r24, r1, PT_R24
+ lwi r23, r1, PT_R23
+ lwi r22, r1, PT_R22
+ lwi r21, r1, PT_R21
+ lwi r20, r1, PT_R20
+ lwi r19, r1, PT_R19
+ lwi r18, r1, PT_R18
+ lwi r17, r1, PT_R17
+ lwi r16, r1, PT_R16
+ lwi r15, r1, PT_R15
+ lwi r14, r1, PT_PC
+ lwi r13, r1, PT_R13
+ lwi r12, r1, PT_R12
+ lwi r11, r1, PT_R11
+ lwi r10, r1, PT_R10
+ lwi r9, r1, PT_R9
+ lwi r8, r1, PT_R8
+ lwi r7, r1, PT_R7
+ lwi r6, r1, PT_R6
+ lwi r5, r1, PT_R5
+ lwi r4, r1, PT_R4 /* return val */
+ lwi r3, r1, PT_R3 /* return val */
+ lwi r2, r1, PT_R2
+ lwi r1, r1, PT_R1
+
+ rtid r14, 0
+ nop
+
+sys_vfork_wrapper:
+ brid sys_vfork
+ addk r5, r1, r0
+
+sys_clone_wrapper:
+ brid sys_clone
+ addk r7, r1, r0
+
+sys_execve_wrapper:
+ brid sys_execve
+ addk r8, r1, r0
+
+sys_sigreturn_wrapper:
+ brid sys_sigreturn
+ addk r5, r1, r0
+
+sys_rt_sigreturn_wrapper:
+ brid sys_rt_sigreturn
+ addk r5, r1, r0
+
+sys_sigsuspend_wrapper:
+ brid sys_rt_sigsuspend
+ addk r6, r1, r0
+
+sys_rt_sigsuspend_wrapper:
+ brid sys_rt_sigsuspend
+ addk r7, r1, r0
+
+ /* Interrupt vector table */
+ .section .init.ivt, "ax"
+ .org 0x0
+ brai _reset
+ brai _user_exception
+ brai _interrupt
+ brai _break
+ brai _hw_exception_handler
+ .org 0x60
+ brai _debug_exception
+
+.section .rodata,"a"
+#include "syscall_table.S"
+
+syscall_table_size=(.-sys_call_table)
--
1.5.4.GIT

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