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Commit 97f1c050 authored by Miles Bader's avatar Miles Bader Committed by Linus Torvalds
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[PATCH] v850 kernel entry fixes and cleanup 

1) Preserve the v850 system-call-number register when handling a signal;
   otherwise system calls will not be correctly restarted afterwards
2) Correctly handle illegal insn exceptions, which need a special
   instruction to return (not reti), and save PC/PSW to a different place
2) Remove some unnecessary register saving in the trap handler
3) Consolidate various places that use the register save/restore macros
4) Eliminate some unused compile-time configuration stuff
5) A bit of whitespace and other syntactic cleanup
parent 8e5da0eb
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Showing with 251 additions and 262 deletions
arch/v850/kernel/bug.c
View file @ 97f1c050
/*
* arch/v850/kernel/bug.c -- Bug reporting functions
*
* Copyright (C) 2001,02 NEC Corporation
* Copyright (C) 2001,02 Miles Bader <miles@gnu.org>
* Copyright (C) 2001,02,03 NEC Electronics Corporation
* Copyright (C) 2001,02,03 Miles Bader <miles@gnu.org>
*
* 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
......@@ -40,12 +40,6 @@ int bad_trap (int trap_num, struct pt_regs *regs)
return -ENOSYS;
}
int debug_trap (struct pt_regs *regs)
{
printk (KERN_CRIT "debug trap at 0x%08lx!\n", regs->pc);
return -ENOSYS;
}
#ifdef CONFIG_RESET_GUARD
void unexpected_reset (unsigned long ret_addr, unsigned long kmode,
struct task_struct *task, unsigned long sp)
......
arch/v850/kernel/entry.S
View file @ 97f1c050
......@@ -2,8 +2,8 @@
* arch/v850/kernel/entry.S -- Low-level system-call handling, trap handlers,
* and context-switching
*
* Copyright (C) 2001,02 NEC Corporation
* Copyright (C) 2001,02 Miles Bader <miles@gnu.org>
* Copyright (C) 2001,02,03 NEC Electronics Corporation
* Copyright (C) 2001,02,03 Miles Bader <miles@gnu.org>
*
* 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
......@@ -38,27 +38,27 @@
sst.w r6, PTO+PT_GPR(6)[ep]; \
sst.w r7, PTO+PT_GPR(7)[ep]; \
sst.w r8, PTO+PT_GPR(8)[ep]; \
sst.w r9, PTO+PT_GPR(9)[ep];
sst.w r9, PTO+PT_GPR(9)[ep]
/* Restore argument registers from the struct pt_regs pointed to by EP. */
#define RESTORE_ARG_REGS \
sld.w PTO+PT_GPR(6)[ep], r6; \
sld.w PTO+PT_GPR(7)[ep], r7; \
sld.w PTO+PT_GPR(8)[ep], r8; \
sld.w PTO+PT_GPR(9)[ep], r9;
sld.w PTO+PT_GPR(9)[ep], r9
/* Save value return registers to the struct pt_regs pointed to by EP. */
#define SAVE_RVAL_REGS \
sst.w r10, PTO+PT_GPR(10)[ep]; \
sst.w r11, PTO+PT_GPR(11)[ep];
sst.w r11, PTO+PT_GPR(11)[ep]
/* Restore value return registers from the struct pt_regs pointed to by EP. */
#define RESTORE_RVAL_REGS \
sld.w PTO+PT_GPR(10)[ep], r10; \
sld.w PTO+PT_GPR(11)[ep], r11;
sld.w PTO+PT_GPR(11)[ep], r11
#define SAVE_CALL_CLOBBERED_REGS_BEFORE_ARGS \
sst.w r1, PTO+PT_GPR(1)[ep]; \
sst.w r5, PTO+PT_GPR(5)[ep];
sst.w r5, PTO+PT_GPR(5)[ep]
#define SAVE_CALL_CLOBBERED_REGS_AFTER_RVAL \
sst.w r12, PTO+PT_GPR(12)[ep]; \
sst.w r13, PTO+PT_GPR(13)[ep]; \
......@@ -67,10 +67,10 @@
sst.w r16, PTO+PT_GPR(16)[ep]; \
sst.w r17, PTO+PT_GPR(17)[ep]; \
sst.w r18, PTO+PT_GPR(18)[ep]; \
sst.w r19, PTO+PT_GPR(19)[ep];
sst.w r19, PTO+PT_GPR(19)[ep]
#define RESTORE_CALL_CLOBBERED_REGS_BEFORE_ARGS \
sld.w PTO+PT_GPR(1)[ep], r1; \
sld.w PTO+PT_GPR(5)[ep], r5;
sld.w PTO+PT_GPR(5)[ep], r5
#define RESTORE_CALL_CLOBBERED_REGS_AFTER_RVAL \
sld.w PTO+PT_GPR(12)[ep], r12; \
sld.w PTO+PT_GPR(13)[ep], r13; \
......@@ -79,40 +79,34 @@
sld.w PTO+PT_GPR(16)[ep], r16; \
sld.w PTO+PT_GPR(17)[ep], r17; \
sld.w PTO+PT_GPR(18)[ep], r18; \
sld.w PTO+PT_GPR(19)[ep], r19;
sld.w PTO+PT_GPR(19)[ep], r19
/* Save `call clobbered' registers to the struct pt_regs pointed to by EP. */
#define SAVE_CALL_CLOBBERED_REGS \
SAVE_CALL_CLOBBERED_REGS_BEFORE_ARGS; \
SAVE_ARG_REGS; \
SAVE_RVAL_REGS; \
SAVE_CALL_CLOBBERED_REGS_AFTER_RVAL;
SAVE_CALL_CLOBBERED_REGS_AFTER_RVAL
/* Restore `call clobbered' registers from the struct pt_regs pointed to
by EP. */
#define RESTORE_CALL_CLOBBERED_REGS \
RESTORE_CALL_CLOBBERED_REGS_BEFORE_ARGS; \
RESTORE_ARG_REGS; \
RESTORE_RVAL_REGS; \
RESTORE_CALL_CLOBBERED_REGS_AFTER_RVAL;
RESTORE_CALL_CLOBBERED_REGS_AFTER_RVAL
/* Save `call clobbered' registers except for the return-value registers
to the struct pt_regs pointed to by EP. */
#define SAVE_CALL_CLOBBERED_REGS_NO_RVAL \
SAVE_CALL_CLOBBERED_REGS_BEFORE_ARGS; \
SAVE_ARG_REGS; \
SAVE_CALL_CLOBBERED_REGS_AFTER_RVAL;
SAVE_CALL_CLOBBERED_REGS_AFTER_RVAL
/* Restore `call clobbered' registers except for the return-value registers
from the struct pt_regs pointed to by EP. */
#define RESTORE_CALL_CLOBBERED_REGS_NO_RVAL \
RESTORE_CALL_CLOBBERED_REGS_BEFORE_ARGS; \
RESTORE_ARG_REGS; \
RESTORE_CALL_CLOBBERED_REGS_AFTER_RVAL;
/* Zero `call clobbered' registers except for the return-value registers. */
#define ZERO_CALL_CLOBBERED_REGS_NO_RVAL \
mov r0, r1; mov r0, r5; \
mov r0, r12; mov r0, r13; mov r0, r14; mov r0, r15; \
mov r0, r16; mov r0, r17; mov r0, r18; mov r0, r19;
RESTORE_CALL_CLOBBERED_REGS_AFTER_RVAL
/* Save `call saved' registers to the struct pt_regs pointed to by EP. */
#define SAVE_CALL_SAVED_REGS \
......@@ -126,7 +120,7 @@
sst.w r26, PTO+PT_GPR(26)[ep]; \
sst.w r27, PTO+PT_GPR(27)[ep]; \
sst.w r28, PTO+PT_GPR(28)[ep]; \
sst.w r29, PTO+PT_GPR(29)[ep];
sst.w r29, PTO+PT_GPR(29)[ep]
/* Restore `call saved' registers from the struct pt_regs pointed to by EP. */
#define RESTORE_CALL_SAVED_REGS \
sld.w PTO+PT_GPR(2)[ep], r2; \
......@@ -139,68 +133,53 @@
sld.w PTO+PT_GPR(26)[ep], r26; \
sld.w PTO+PT_GPR(27)[ep], r27; \
sld.w PTO+PT_GPR(28)[ep], r28; \
sld.w PTO+PT_GPR(29)[ep], r29;
sld.w PTO+PT_GPR(29)[ep], r29
/* Save the PC stored in the special register SAVEREG to the struct pt_regs
pointed to by EP. r19 is clobbered. */
#define SAVE_PC(savereg) \
stsr SR_ ## savereg, r19; \
sst.w r19, PTO+PT_PC[ep]
/* Restore the PC from the struct pt_regs pointed to by EP, to the special
register SAVEREG. LP is clobbered (it is used as a scratch register
because the POP_STATE macro restores it, and this macro is usually used
inside POP_STATE). */
#define RESTORE_PC(savereg) \
sld.w PTO+PT_PC[ep], lp; \
ldsr lp, SR_ ## savereg
/* Save the PSW register stored in the special register SAVREG to the
struct pt_regs pointed to by EP r19 is clobbered. */
#define SAVE_PSW(savereg) \
stsr SR_ ## savereg, r19; \
sst.w r19, PTO+PT_PSW[ep]
/* Restore the PSW register from the struct pt_regs pointed to by EP, to
the special register SAVEREG. LP is clobbered (it is used as a scratch
register because the POP_STATE macro restores it, and this macro is
usually used inside POP_STATE). */
#define RESTORE_PSW(savereg) \
sld.w PTO+PT_PSW[ep], lp; \
ldsr lp, SR_ ## savereg
/* Save system registers to the struct pt_regs pointed to by REG.
/* Save CTPC/CTPSW/CTBP registers to the struct pt_regs pointed to by REG.
r19 is clobbered. */
#define SAVE_SYS_REGS \
stsr SR_EIPC, r19; /* user's PC, before interrupt */ \
sst.w r19, PTO+PT_PC[ep]; \
stsr SR_EIPSW, r19; /* & PSW (XXX save this?) */ \
sst.w r19, PTO+PT_PSW[ep]; \
stsr SR_CTPC, r19; /* (XXX maybe not used in kernel?) */ \
#define SAVE_CT_REGS \
stsr SR_CTPC, r19; \
sst.w r19, PTO+PT_CTPC[ep]; \
stsr SR_CTPSW, r19; /* " */ \
stsr SR_CTPSW, r19; \
sst.w r19, PTO+PT_CTPSW[ep]; \
stsr SR_CTBP, r19; /* " */ \
sst.w r19, PTO+PT_CTBP[ep];
/* Restore system registers from the struct pt_regs pointed to by EP.
stsr SR_CTBP, r19; \
sst.w r19, PTO+PT_CTBP[ep]
/* Restore CTPC/CTPSW/CTBP registers from the struct pt_regs pointed to by EP.
LP is clobbered (it is used as a scratch register because the POP_STATE
macro restores it, and this macro is usually used inside POP_STATE). */
#define RESTORE_SYS_REGS \
sld.w PTO+PT_PC[ep], lp; \
ldsr lp, SR_EIPC; /* user's PC, before interrupt */ \
sld.w PTO+PT_PSW[ep], lp; \
ldsr lp, SR_EIPSW; /* & PSW (XXX save this?) */ \
#define RESTORE_CT_REGS \
sld.w PTO+PT_CTPC[ep], lp; \
ldsr lp, SR_CTPC; /* (XXX maybe not used in kernel?) */ \
ldsr lp, SR_CTPC; \
sld.w PTO+PT_CTPSW[ep], lp; \
ldsr lp, SR_CTPSW; /* " */ \
ldsr lp, SR_CTPSW; \
sld.w PTO+PT_CTBP[ep], lp; \
ldsr lp, SR_CTBP; /* " */
/* Save system registers to the struct pt_regs pointed to by REG. This is a
NMI-specific version, because NMIs save the PC/PSW in a different place
than other interrupt requests. r19 is clobbered. */
#define SAVE_SYS_REGS_FOR_NMI \
stsr SR_FEPC, r19; /* user's PC, before NMI */ \
sst.w r19, PTO+PT_PC[ep]; \
stsr SR_FEPSW, r19; /* & PSW (XXX save this?) */ \
sst.w r19, PTO+PT_PSW[ep]; \
stsr SR_CTPC, r19; /* (XXX maybe not used in kernel?) */ \
sst.w r19, PTO+PT_CTPC[ep]; \
stsr SR_CTPSW, r19; /* " */ \
sst.w r19, PTO+PT_CTPSW[ep]; \
stsr SR_CTBP, r19; /* " */ \
sst.w r19, PTO+PT_CTBP[ep];
/* Restore system registers from the struct pt_regs pointed to by EP. This is
a NMI-specific version, because NMIs save the PC/PSW in a different place
than other interrupt requests. LP is clobbered (it is used as a scratch
register because the POP_STATE macro restores it, and this macro is usually
used inside POP_STATE). */
#define RESTORE_SYS_REGS_FOR_NMI \
ldsr lp, SR_FEPC; /* user's PC, before NMI */ \
sld.w PTO+PT_PC[ep], lp; \
ldsr lp, SR_FEPSW; /* & PSW (XXX save this?) */ \
sld.w PTO+PT_PSW[ep], lp; \
ldsr lp, SR_CTPC; /* (XXX maybe not used in kernel?) */ \
sld.w PTO+PT_CTPC[ep], lp; \
ldsr lp, SR_CTPSW; /* " */ \
sld.w PTO+PT_CTPSW[ep], lp; \
ldsr lp, SR_CTBP; /* " */ \
sld.w PTO+PT_CTBP[ep], lp;
ldsr lp, SR_CTBP
/* Push register state, except for the stack pointer, on the stack in the form
......@@ -213,7 +192,7 @@
mov sp, ep; \
sst.w gp, PTO+PT_GPR(GPR_GP)[ep]; \
sst.w lp, PTO+PT_GPR(GPR_LP)[ep]; \
type ## _STATE_SAVER;
type ## _STATE_SAVER
/* Pop a register state, except for the stack pointer, from the struct pt_regs
on the stack. */
#define POP_STATE(type) \
......@@ -222,161 +201,175 @@
sld.w PTO+PT_GPR(GPR_GP)[ep], gp; \
sld.w PTO+PT_GPR(GPR_LP)[ep], lp; \
sld.w PTO+PT_GPR(GPR_EP)[ep], ep; \
addi STATE_SAVE_SIZE, sp, sp; /* Clean up our stack space. */
/* Switch to the kernel stack if necessary, and push register state on
the stack in the form of a struct pt_regs. Also load the current
task pointer if switching from user mode. The stack-pointer (r3)
should have already been saved to the memory location SP_SAVE_LOC
(the reason for this is that the interrupt vectors may be beyond a
22-bit signed offset jump from the actual interrupt handler, and this
allows them to save the stack-pointer and use that register to do an
indirect jump). This macro makes sure that `special' registers,
system registers, and the stack pointer are saved; TYPE identifies
the set of extra registers to be saved as well. SYSCALL_NUM is the
register in which the system-call number this state is for is stored
(r0 if this isn't a system call). Interrupts should already be
disabled when calling this. */
addi STATE_SAVE_SIZE, sp, sp /* Clean up our stack space. */
/* Switch to the kernel stack if necessary, and push register state on the
stack in the form of a struct pt_regs. Also load the current task
pointer if switching from user mode. The stack-pointer (r3) should have
already been saved to the memory location SP_SAVE_LOC (the reason for
this is that the interrupt vectors may be beyond a 22-bit signed offset
jump from the actual interrupt handler, and this allows them to save the
stack-pointer and use that register to do an indirect jump). This macro
makes sure that `special' registers, system registers, and the stack
pointer are saved; TYPE identifies the set of extra registers to be
saved as well. SYSCALL_NUM is the register in which the system-call
number this state is for is stored (r0 if this isn't a system call).
Interrupts should already be disabled when calling this. */
#define SAVE_STATE(type, syscall_num, sp_save_loc) \
tst1 0, KM; /* See if already in kernel mode. */ \
bz 1f; \
/* Kernel-mode state save. */ \
ld.w sp_save_loc, sp; /* Reload kernel stack-pointer. */ \
st.w sp, (PT_GPR(GPR_SP)-PT_SIZE)[sp]; /* Save original SP. */ \
PUSH_STATE(type); \
mov 1, r19; /* Was in kernel-mode. */ \
sst.w r19, PTO+PT_KERNEL_MODE[ep]; /* [ep is set by PUSH_STATE] */ \
ld.w sp_save_loc, sp; /* ... yes, use saved SP. */ \
br 2f; \
1: /* User-mode state save. */ \
ld.w KSP, sp; /* Switch to kernel stack. */ \
PUSH_STATE(type); \
sst.w r0, PTO+PT_KERNEL_MODE[ep]; /* Was in user-mode. */ \
ld.w sp_save_loc, r19; \
sst.w r19, PTO+PT_GPR(GPR_SP)[ep]; /* Store user SP. */ \
mov 1, r19; \
st.b r19, KM; /* Now we're in kernel-mode. */ \
1: ld.w KSP, sp; /* ... no, switch to kernel stack. */ \
2: PUSH_STATE(type); \
ld.b KM, r19; /* Remember old kernel-mode. */ \
sst.w r19, PTO+PT_KERNEL_MODE[ep]; \
ld.w sp_save_loc, r19; /* Remember old SP. */ \
sst.w r19, PTO+PT_GPR(GPR_SP)[ep]; \
mov 1, r19; /* Now definitely in kernel-mode. */ \
st.b r19, KM; \
GET_CURRENT_TASK(CURRENT_TASK); /* Fetch the current task pointer. */ \
2: /* Save away the syscall number. */ \
/* Save away the syscall number. */ \
sst.w syscall_num, PTO+PT_SYSCALL[ep]
/* Save register state not normally saved by PUSH_STATE for TYPE. */
#define SAVE_EXTRA_STATE(type) \
mov sp, ep; \
type ## _EXTRA_STATE_SAVER;
type ## _EXTRA_STATE_SAVER
/* Restore register state not normally restored by POP_STATE for TYPE. */
#define RESTORE_EXTRA_STATE(type) \
mov sp, ep; \
type ## _EXTRA_STATE_RESTORER;
type ## _EXTRA_STATE_RESTORER
/* Save any call-clobbered registers not normally saved by PUSH_STATE
for TYPE. */
#define SAVE_EXTRA_STATE_FOR_FUNCALL(type) \
mov sp, ep; \
type ## _FUNCALL_EXTRA_STATE_SAVER;
type ## _FUNCALL_EXTRA_STATE_SAVER
/* Restore any call-clobbered registers not normally restored by POP_STATE for
TYPE. */
#define RESTORE_EXTRA_STATE_FOR_FUNCALL(type) \
mov sp, ep; \
type ## _FUNCALL_EXTRA_STATE_RESTORER;
/* These are extra_state_saver/restorer values for a user trap. Note that we
save the argument registers so that restarted syscalls will function
properly (otherwise it wouldn't be necessary), and we must _not_ restore
the return-value registers (so that traps can return a value!), but there
are various options for what happens to other call-clobbered registers,
selected by preprocessor conditionals. */
#if TRAPS_PRESERVE_CALL_CLOBBERED_REGS
type ## _FUNCALL_EXTRA_STATE_RESTORER
/* Traps save/restore all call-clobbered registers (except for rval regs). */
#define TRAP_STATE_SAVER \
SAVE_CALL_CLOBBERED_REGS_NO_RVAL; \
SAVE_SYS_REGS
#define TRAP_STATE_RESTORER \
RESTORE_CALL_CLOBBERED_REGS_NO_RVAL; \
RESTORE_SYS_REGS
#else /* !TRAPS_PRESERVE_CALL_CLOBBERED_REGS */
/* These are extra_state_saver/restorer values for a user trap. Note
that we save the argument registers so that restarted syscalls will
function properly (otherwise it wouldn't be necessary), and we must
_not_ restore the return-value registers (so that traps can return a
value!), but call-clobbered registers are not saved at all, as the
caller of the syscall function should have saved them. */
#define TRAP_RET reti
/* Traps don't save call-clobbered registers (but do still save arg regs). */
#define TRAP_STATE_SAVER \
SAVE_ARG_REGS; \
SAVE_SYS_REGS
#if TRAPS_ZERO_CALL_CLOBBERED_REGS
/* Traps zero call-clobbered registers (except for arg/rval regs) before
returning from a system call, to avoid any internal values from leaking out
of the kernel. */
#define TRAP_STATE_RESTORER \
ZERO_CALL_CLOBBERED_REGS_NO_ARGS_NO_RVAL; \
RESTORE_ARG_REGS; \
RESTORE_SYS_REGS
#else /* !TRAPS_ZERO_CALL_CLOBBERED_REGS */
SAVE_PC(EIPC)
/* When traps return, they just leave call-clobbered registers (except for arg
regs) with whatever value they have from the kernel. */
#define TRAP_STATE_RESTORER \
RESTORE_ARG_REGS; \
RESTORE_SYS_REGS
#endif /* TRAPS_ZERO_CALL_CLOBBERED_REGS */
#endif /* TRAPS_PRESERVE_CALL_CLOBBERED_REGS */
/* Save registers not normally saved by traps. */
RESTORE_PC(EIPC)
/* Save registers not normally saved by traps. We need to save r12, even
though it's nominally call-clobbered, because it's used when restarting
a system call (the signal-handling path uses SAVE_EXTRA_STATE, and
expects r12 to be restored when the trap returns). Similarly, we must
save the PSW, so that it's at least in a known state in the the pt_regs
structure. */
#define TRAP_EXTRA_STATE_SAVER \
SAVE_RVAL_REGS; \
SAVE_CALL_SAVED_REGS
sst.w r12, PTO+PT_GPR(12)[ep]; \
SAVE_CALL_SAVED_REGS; \
SAVE_PSW(EIPSW); \
SAVE_CT_REGS
#define TRAP_EXTRA_STATE_RESTORER \
RESTORE_RVAL_REGS; \
RESTORE_CALL_SAVED_REGS
sld.w PTO+PT_GPR(12)[ep], r12; \
RESTORE_CALL_SAVED_REGS; \
RESTORE_PSW(EIPSW); \
RESTORE_CT_REGS
#define TRAP_FUNCALL_EXTRA_STATE_SAVER \
SAVE_RVAL_REGS
#define TRAP_FUNCALL_EXTRA_STATE_RESTORER \
RESTORE_RVAL_REGS
/* Register saving/restoring for maskable interrupts. */
#define IRQ_RET reti
#define IRQ_STATE_SAVER \
SAVE_CALL_CLOBBERED_REGS; \
SAVE_SYS_REGS
SAVE_PC(EIPC); \
SAVE_PSW(EIPSW)
#define IRQ_STATE_RESTORER \
RESTORE_CALL_CLOBBERED_REGS; \
RESTORE_SYS_REGS
RESTORE_PC(EIPC); \
RESTORE_PSW(EIPSW)
#define IRQ_EXTRA_STATE_SAVER \
SAVE_CALL_SAVED_REGS
SAVE_CALL_SAVED_REGS; \
SAVE_CT_REGS
#define IRQ_EXTRA_STATE_RESTORER \
RESTORE_CALL_SAVED_REGS
RESTORE_CALL_SAVED_REGS; \
RESTORE_CT_REGS
#define IRQ_FUNCALL_EXTRA_STATE_SAVER /* nothing */
#define IRQ_FUNCALL_EXTRA_STATE_RESTORER /* nothing */
/* Register saving/restoring for non-maskable interrupts. */
#define NMI_RET reti
#define NMI_STATE_SAVER \
SAVE_CALL_CLOBBERED_REGS; \
SAVE_SYS_REGS_FOR_NMI
SAVE_PC(FEPC); \
SAVE_PSW(FEPSW);
#define NMI_STATE_RESTORER \
RESTORE_CALL_CLOBBERED_REGS; \
RESTORE_SYS_REGS_FOR_NMI
RESTORE_PC(FEPC); \
RESTORE_PSW(FEPSW);
#define NMI_EXTRA_STATE_SAVER \
SAVE_CALL_SAVED_REGS
SAVE_CALL_SAVED_REGS; \
SAVE_CT_REGS
#define NMI_EXTRA_STATE_RESTORER \
RESTORE_CALL_SAVED_REGS
RESTORE_CALL_SAVED_REGS; \
RESTORE_CT_REGS
#define NMI_FUNCALL_EXTRA_STATE_SAVER /* nothing */
#define NMI_FUNCALL_EXTRA_STATE_RESTORER /* nothing */
/* Register saving/restoring for a context switch. We don't need to save too
many registers, because context-switching looks like a function call (via
the function `switch_thread'), so callers will save any call-clobbered
registers themselves. The stack pointer and return value are handled by
switch_thread itself. */
/* Register saving/restoring for debug traps. */
#define DBTRAP_RET .long 0x014607E0 /* `dbret', but gas doesn't support it. */
#define DBTRAP_STATE_SAVER \
SAVE_CALL_CLOBBERED_REGS; \
SAVE_PC(DBPC); \
SAVE_PSW(DBPSW)
#define DBTRAP_STATE_RESTORER \
RESTORE_CALL_CLOBBERED_REGS; \
RESTORE_PC(DBPC); \
RESTORE_PSW(DBPSW)
#define DBTRAP_EXTRA_STATE_SAVER \
SAVE_CALL_SAVED_REGS; \
SAVE_CT_REGS
#define DBTRAP_EXTRA_STATE_RESTORER \
RESTORE_CALL_SAVED_REGS; \
RESTORE_CT_REGS
#define DBTRAP_FUNCALL_EXTRA_STATE_SAVER /* nothing */
#define DBTRAP_FUNCALL_EXTRA_STATE_RESTORER /* nothing */
/* Register saving/restoring for a context switch. We don't need to save
too many registers, because context-switching looks like a function call
(via the function `switch_thread'), so callers will save any
call-clobbered registers themselves. We do need to save the CT regs, as
they're normally not saved during kernel entry (the kernel doesn't use
them). We save PSW so that interrupt-status state will correctly follow
each thread (mostly NMI vs. normal-IRQ/trap), though for the most part
it doesn't matter since threads are always in almost exactly the same
processor state during a context switch. The stack pointer and return
value are handled by switch_thread itself. */
#define SWITCH_STATE_SAVER \
SAVE_CALL_SAVED_REGS
SAVE_CALL_SAVED_REGS; \
SAVE_PSW(PSW); \
SAVE_CT_REGS
#define SWITCH_STATE_RESTORER \
RESTORE_CALL_SAVED_REGS
RESTORE_CALL_SAVED_REGS; \
RESTORE_PSW(PSW); \
RESTORE_CT_REGS
/* Restore register state from the struct pt_regs on the stack, switch back
......@@ -400,24 +393,27 @@
andi _TIF_SIGPENDING, r19, r0; \
bnz 4f; /* Signals to handle, handle them */ \
\
/* Finally, return to user state. */ \
/* Return to user state. */ \
1: st.b r0, KM; /* Now officially in user state. */ \
POP_STATE(type); \
st.w sp, KSP; /* Save the kernel stack pointer. */ \
ld.w PT_GPR(GPR_SP)-PT_SIZE[sp], sp; \
/* Restore user stack pointer. */ \
reti; \
\
/* Return to kernel state. */ \
/* Final return. The stack-pointer fiddling is not needed when returning \
to kernel-mode, but they don't hurt, and this way we can share the \
(somtimes rather lengthy) POP_STATE macro. */ \
2: POP_STATE(type); \
reti; \
st.w sp, KSP; /* Save the kernel stack pointer. */ \
ld.w PT_GPR(GPR_SP)-PT_SIZE[sp], sp; /* Restore stack pointer. */ \
type ## _RET; /* Return from the trap/interrupt. */ \
\
/* Call the scheduler before returning from a syscall/trap. */ \
3: SAVE_EXTRA_STATE_FOR_FUNCALL(type); /* Prepare for funcall. */ \
jarl CSYM(schedule), lp; /* Call scheduler */ \
di; /* The scheduler enables interrupts */\
RESTORE_EXTRA_STATE_FOR_FUNCALL(type); \
br 1b; \
GET_CURRENT_THREAD(r18); \
ld.w TI_FLAGS[r18], r19; \
andi _TIF_SIGPENDING, r19, r0; \
bz 1b; /* No signals, return. */ \
/* Signals to handle, fall through to handle them. */ \
\
/* Handle a signal return. */ \
4: /* Not all registers are saved by the normal trap/interrupt entry \
......@@ -428,13 +424,13 @@
complete register state. Here we save anything not saved by \
the normal entry sequence, so that it may be safely restored \
(in a possibly modified form) after do_signal returns. */ \
SAVE_EXTRA_STATE(type) /* Save state not saved by entry. */ \
SAVE_EXTRA_STATE(type); /* Save state not saved by entry. */ \
movea PTO, sp, r6; /* Arg 1: struct pt_regs *regs */ \
mov r0, r7; /* Arg 2: sigset_t *oldset */ \
jarl CSYM(do_signal), lp; /* Handle any signals */ \
di; /* sig handling enables interrupts */ \
RESTORE_EXTRA_STATE(type); /* Restore extra regs. */ \
br 1b;
br 1b
/* Jump to the appropriate function for the system call number in r12
......@@ -454,7 +450,7 @@
jmp [r12]; \
/* The syscall number is invalid, return an error. */ \
1: addi -ENOSYS, r0, r10; \
jmp [lp];
jmp [lp]
.text
......@@ -537,18 +533,15 @@ L_ENTRY(syscall_long):
st.w r13, 16[sp] // arg 5
st.w r14, 20[sp] // arg 6
#if !TRAPS_PRESERVE_CALL_CLOBBERED_REGS
// Make sure r13 and r14 are preserved, in case we have to restart a
// system call because of a signal (ep has already been set by caller).
st.w r13, PTO+PT_GPR(13)[sp]
st.w r14, PTO+PT_GPR(13)[sp]
mov hilo(ret_from_long_syscall), lp
#endif /* !TRAPS_PRESERVE_CALL_CLOBBERED_REGS */
MAKE_SYS_CALL // Jump to the syscall function.
END(syscall_long)
#if !TRAPS_PRESERVE_CALL_CLOBBERED_REGS
/* Entry point used to return from a long syscall. Only needed to restore
r13/r14 if the general trap mechanism doesnt' do so. */
L_ENTRY(ret_from_long_syscall):
......@@ -556,7 +549,6 @@ L_ENTRY(ret_from_long_syscall):
ld.w PTO+PT_GPR(13)[sp], r14
br ret_from_trap // The rest is the same as other traps
END(ret_from_long_syscall)
#endif /* !TRAPS_PRESERVE_CALL_CLOBBERED_REGS */
/* These syscalls need access to the struct pt_regs on the stack, so we
......@@ -564,14 +556,11 @@ END(ret_from_long_syscall)
L_ENTRY(sys_fork_wrapper):
#ifdef CONFIG_MMU
// Save state not saved by entry. This is actually slight overkill;
// it's actually only necessary to save any state restored by
// switch_thread that's not saved by the trap entry.
SAVE_EXTRA_STATE(TRAP) // Save state not saved by entry.
addi SIGCHLD, r0, r6 // Arg 0: flags
ld.w PTO+PT_GPR(GPR_SP)[sp], r7 // Arg 1: child SP (use parent's)
movea PTO, sp, r8 // Arg 2: parent context
jr CSYM(fork_common) // Do real work (tail-call).
mov hilo(CSYM(fork_common)), r18// Where the real work gets done
br save_extra_state_tramp // Save state and go there
#else
// fork almost works, enough to trick you into looking elsewhere :-(
addi -EINVAL, r0, r10
......@@ -580,60 +569,66 @@ L_ENTRY(sys_fork_wrapper):
END(sys_fork_wrapper)
L_ENTRY(sys_vfork_wrapper):
// Save state not saved by entry. This is actually slight overkill;
// it's actually only necessary to save any state restored by
// switch_thread that's not saved by the trap entry.
SAVE_EXTRA_STATE(TRAP) // Save state not saved by entry.
addi CLONE_VFORK | CLONE_VM | SIGCHLD, r0, r6 // Arg 0: flags
ld.w PTO+PT_GPR(GPR_SP)[sp], r7 // Arg 1: child SP (use parent's)
movea PTO, sp, r8 // Arg 2: parent context
jr CSYM(fork_common) // Do real work (tail-call).
mov hilo(CSYM(fork_common)), r18// Where the real work gets done
br save_extra_state_tramp // Save state and go there
END(sys_vfork_wrapper)
L_ENTRY(sys_clone_wrapper):
// Save state not saved by entry. This is actually slight overkill;
// it's actually only necessary to save any state restored by
// switch_thread that's not saved by the trap entry.
SAVE_EXTRA_STATE(TRAP) // Save state not saved by entry.
ld.w PTO+PT_GPR(GPR_SP)[sp], r19 // parent's stack pointer
cmp r7, r0 // See if child SP arg (arg 1) is 0.
cmov z, r19, r7, r7 // ... and use the parent's if so.
movea PTO, sp, r8 // Arg 2: parent context
jr CSYM(fork_common) // Do real work (tail-call).
mov hilo(CSYM(fork_common)), r18// Where the real work gets done
br save_extra_state_tramp // Save state and go there
END(sys_clone_wrapper)
L_ENTRY(sys_execve_wrapper):
movea PTO, sp, r9 // add user context as 4th arg
jr CSYM(sys_execve) // Do real work (tail-call).
END(sys_execve_wrapper)
L_ENTRY(sys_sigsuspend_wrapper):
SAVE_EXTRA_STATE(TRAP) // Save state not saved by entry.
movea PTO, sp, r7 // add user context as 2nd arg
jarl CSYM(sys_sigsuspend), lp// Do real work.
mov hilo(CSYM(sys_sigsuspend)), r18 // syscall function
jarl save_extra_state_tramp, lp // Save state and do it
br restore_extra_regs_and_ret_from_trap
END(sys_sigsuspend_wrapper)
L_ENTRY(sys_rt_sigsuspend_wrapper):
SAVE_EXTRA_STATE(TRAP) // Save state not saved by entry.
movea PTO, sp, r8 // add user context as 3rd arg
jarl CSYM(sys_rt_sigsuspend), lp // Do real work.
mov hilo(CSYM(sys_rt_sigsuspend)), r18 // syscall function
jarl save_extra_state_tramp, lp // Save state and do it
br restore_extra_regs_and_ret_from_trap
END(sys_rt_sigsuspend_wrapper)
L_ENTRY(sys_sigreturn_wrapper):
SAVE_EXTRA_STATE(TRAP) // Save state not saved by entry.
movea PTO, sp, r6 // add user context as 1st arg
jarl CSYM(sys_sigreturn), lp // Do real work.
mov hilo(CSYM(sys_sigreturn)), r18 // syscall function
jarl save_extra_state_tramp, lp // Save state and do it
br restore_extra_regs_and_ret_from_trap
END(sys_sigreturn_wrapper)
L_ENTRY(sys_rt_sigreturn_wrapper):
SAVE_EXTRA_STATE(TRAP) // Save state not saved by entry.
movea PTO, sp, r6 // add user context as 1st arg
jarl CSYM(sys_rt_sigreturn), lp // Do real work.
mov hilo(CSYM(sys_rt_sigreturn)), r18 // syscall function
jarl save_extra_state_tramp, lp // Save state and do it
br restore_extra_regs_and_ret_from_trap
END(sys_rt_sigreturn_wrapper)
/* Save any state not saved by SAVE_STATE(TRAP), and jump to r18.
It's main purpose is to share the rather lengthy code sequence that
SAVE_STATE expands into among the above wrapper functions. */
L_ENTRY(save_extra_state_tramp):
SAVE_EXTRA_STATE(TRAP) // Save state not saved by entry.
jmp [r18] // Do the work the caller wants
END(save_extra_state_tramp)
/*
* Hardware maskable interrupts.
*
......@@ -658,37 +653,40 @@ G_ENTRY(irq):
shr 20, r6 // shift back, and remove lower nibble
add -8, r6 // remove bias for irqs
// If the IRQ index is negative, it's actually one of the exception
// traps below 0x80 (currently, the illegal instruction trap, and
// the `debug trap'). Handle these separately.
bn exception
// Call the high-level interrupt handling code.
jarl CSYM(handle_irq), lp
// fall through
/* Entry point used to return from an interrupt (also used by exception
handlers, below). */
ret_from_irq:
RETURN(IRQ)
END(irq)
exception:
mov hilo(ret_from_irq), lp // where the handler should return
cmp -2, r6
bne 1f
// illegal instruction exception
addi SIGILL, r0, r6 // Arg 0: signal number
/*
* Debug trap / illegal-instruction exception
*
* The stack-pointer (r3) should have already been saved to the memory
* location ENTRY_SP (the reason for this is that the interrupt vectors may be
* beyond a 22-bit signed offset jump from the actual interrupt handler, and
* this allows them to save the stack-pointer and use that register to do an
* indirect jump).
*/
G_ENTRY(dbtrap):
SAVE_STATE (DBTRAP, r0, ENTRY_SP)// Save registers.
/* Look to see if the preceding instruction was is a dbtrap or not,
to decide which signal we should use. */
stsr SR_DBPC, r19 // PC following trapping insn
ld.hu -2[r19], r19
mov SIGTRAP, r6
ori 0xf840, r0, r20 // DBTRAP insn
cmp r19, r20 // Was this trap caused by DBTRAP?
cmov ne, SIGILL, r6, r6 // Choose signal appropriately
/* Raise the desired signal. */
mov CURRENT_TASK, r7 // Arg 1: task
jr CSYM(force_sig) // tail call
1: cmp -1, r6
bne bad_trap_wrapper
// `dbtrap' exception
movea PTO, sp, r6 // Arg 0: user regs
jr CSYM(debug_trap) // tail call
jarl CSYM(force_sig), lp // tail call
END(irq)
RETURN(DBTRAP)
END(dbtrap)
/*
......@@ -711,7 +709,7 @@ G_ENTRY(nmi):
Call the generic IRQ handler, with two arguments, the IRQ number,
and a pointer to the user registers, to handle the specifics.
(we subtract one because the first NMI has code 1). */
addi FIRST_NMI - 1, r6, r6;
addi FIRST_NMI - 1, r6, r6
jarl CSYM(handle_irq), lp
RETURN(NMI)
......
arch/v850/kernel/intv.S
View file @ 97f1c050
/*
* arch/v850/kernel/intv.S -- Interrupt vectors
*
* Copyright (C) 2001,02 NEC Corporation
* Copyright (C) 2001,02 Miles Bader <miles@gnu.org>
* Copyright (C) 2001,02,03 NEC Electronics Corporation
* Copyright (C) 2001,02,03 Miles Bader <miles@gnu.org>
*
* 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
......@@ -40,22 +40,19 @@
/* Generic interrupt vectors. */
.section .intv.common, "ax"
.balign 0x10
JUMP_TO_HANDLER (nmi, NMI_ENTRY_SP) // NMI0
JUMP_TO_HANDLER (nmi, NMI_ENTRY_SP) // 0x10 - NMI0
.balign 0x10
JUMP_TO_HANDLER (nmi, NMI_ENTRY_SP) // NMI1
JUMP_TO_HANDLER (nmi, NMI_ENTRY_SP) // 0x20 - NMI1
.balign 0x10
JUMP_TO_HANDLER (nmi, NMI_ENTRY_SP) // NMI2
JUMP_TO_HANDLER (nmi, NMI_ENTRY_SP) // 0x30 - NMI2
.balign 0x10
JUMP_TO_HANDLER (trap, ENTRY_SP) // TRAP0n
JUMP_TO_HANDLER (trap, ENTRY_SP) // 0x40 - TRAP0n
.balign 0x10
JUMP_TO_HANDLER (trap, ENTRY_SP) // TRAP1n
JUMP_TO_HANDLER (trap, ENTRY_SP) // 0x50 - TRAP1n
.balign 0x10
JUMP_TO_HANDLER (irq, ENTRY_SP) // illegal insn trap
.balign 0x10
JUMP_TO_HANDLER (irq, ENTRY_SP) // DBTRAP insn
JUMP_TO_HANDLER (dbtrap, ENTRY_SP) // 0x60 - Illegal op / DBTRAP insn
/* Hardware interrupt vectors. */
......
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