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-rw-r--r--arch/m68k/kernel/entry.S109
1 files changed, 63 insertions, 46 deletions
diff --git a/arch/m68k/kernel/entry.S b/arch/m68k/kernel/entry.S
index 2cb35e67f..ef5ef46d6 100644
--- a/arch/m68k/kernel/entry.S
+++ b/arch/m68k/kernel/entry.S
@@ -33,12 +33,13 @@
* 10(sp) - d5
* 14(sp) - a0
* 18(sp) - a1
- * 1C(sp) - d0
- * 20(sp) - orig_d0
- * 24(sp) - stack adjustment
- * 28(sp) - sr
- * 2A(sp) - pc
- * 2E(sp) - format & vector
+ * 1C(sp) - a2
+ * 20(sp) - d0
+ * 24(sp) - orig_d0
+ * 28(sp) - stack adjustment
+ * 2C(sp) - sr
+ * 2E(sp) - pc
+ * 32(sp) - format & vector
*/
/*
@@ -47,6 +48,11 @@
* number 0 in the 'current_set' list.
*/
+/*
+ * 97/05/14 Andreas: Register %a2 is now set to the current task throughout
+ * the whole kernel.
+ */
+
#include <linux/sys.h>
#include <linux/config.h>
#include <linux/linkage.h>
@@ -57,6 +63,8 @@
.globl SYMBOL_NAME(kgdb_registers)
#endif
+#define curptr a2
+
LENOSYS = 38
/*
@@ -80,15 +88,15 @@ LTASK_FLAGS = 20
#define MAX_NOINT_IPL 0
#endif /* machine compilation types */
-LD0 = 0x1C
-LORIG_D0 = 0x20
-LSR = 0x28
-LFORMATVEC = 0x2E
+LD0 = 0x20
+LORIG_D0 = 0x24
+LSR = 0x2C
+LFORMATVEC = 0x32
/*
* This defines the normal kernel pt-regs layout.
*
- * regs are a2-a6 and d6-d7 preserved by C code
+ * regs a3-a6 and d6-d7 are preserved by C code
* the kernel doesn't mess with usp unless it needs to
*/
#ifndef CONFIG_KGDB
@@ -96,7 +104,7 @@ LFORMATVEC = 0x2E
clrl %sp@-; /* stk_adj */ \
movel %d0,%sp@-; /* orig d0 */ \
movel %d0,%sp@-; /* d0 */ \
- moveml %d1-%d5/%a0-%a1,%sp@-
+ moveml %d1-%d5/%a0-%a1/%curptr,%sp@-;
#else
/* Need to save the "missing" registers for kgdb...
*/
@@ -104,25 +112,30 @@ LFORMATVEC = 0x2E
clrl %sp@-; /* stk_adj */ \
movel %d0,%sp@-; /* orig d0 */ \
movel %d0,%sp@-; /* d0 */ \
- moveml %d1-%d5/%a0-%a1,%sp@-; \
+ moveml %d1-%d5/%a0-%a1/%curptr,%sp@-; \
moveml %d6-%d7,SYMBOL_NAME(kgdb_registers)+GDBOFFA_D6; \
- moveml %a2-%a6,SYMBOL_NAME(kgdb_registers)+GDBOFFA_A2
+ moveml %a3-%a6,SYMBOL_NAME(kgdb_registers)+GDBOFFA_A3;
#endif
#define RESTORE_ALL \
- moveml %sp@+,%a0-%a1/%d1-%d5; \
+ moveml %sp@+,%a0-%a1/%curptr/%d1-%d5; \
movel %sp@+,%d0; \
addql #4,%sp; /* orig d0 */ \
addl %sp@+,%sp; /* stk adj */ \
rte
-#define SWITCH_STACK_SIZE (7*4+4) /* includes return address */
+#define SWITCH_STACK_SIZE (6*4+4) /* includes return address */
#define SAVE_SWITCH_STACK \
- moveml %a2-%a6/%d6-%d7,%sp@-
+ moveml %a3-%a6/%d6-%d7,%sp@-
#define RESTORE_SWITCH_STACK \
- moveml %sp@+,%a2-%a6/%d6-%d7
+ moveml %sp@+,%a3-%a6/%d6-%d7
+
+#define GET_CURRENT(tmp) \
+ movel %sp,tmp; \
+ andw &-8192,tmp; \
+ movel tmp,%curptr;
.globl SYMBOL_NAME(system_call), SYMBOL_NAME(buserr), SYMBOL_NAME(trap)
.globl SYMBOL_NAME(resume), SYMBOL_NAME(ret_from_exception)
@@ -139,6 +152,7 @@ ENTRY(buserr)
| signifies that the stack frame
| is NOT for syscall
+ GET_CURRENT(%d0)
movel %sp,%sp@- | stack frame pointer argument
bsrl SYMBOL_NAME(buserr_c)
addql #4,%sp
@@ -150,6 +164,7 @@ ENTRY(trap)
movel %d0,%sp@(LORIG_D0) | a -1 in the ORIG_D0 field
| signifies that the stack frame
| is NOT for syscall
+ GET_CURRENT(%d0)
movel %sp,%sp@- | stack frame pointer argument
bsrl SYMBOL_NAME(trap_c)
addql #4,%sp
@@ -190,6 +205,7 @@ ENTRY(system_call)
SAVE_ALL
movel %d0,%d2
+ GET_CURRENT(%d0)
| save top of frame
pea %sp@
jbsr SYMBOL_NAME(set_esp0)
@@ -197,8 +213,7 @@ ENTRY(system_call)
cmpl #NR_syscalls,%d2
jcc badsys
- movel SYMBOL_NAME(current_set),%a0
- btst #5,%a0@(LTASK_FLAGS+3) | PF_TRACESYS
+ btst #5,%curptr@(LTASK_FLAGS+3) | PF_TRACESYS
jne do_trace
jbsr @(SYMBOL_NAME(sys_call_table),%d2:l:4)@(0)
movel %d0,%sp@(LD0) | save the return value
@@ -208,24 +223,23 @@ SYMBOL_NAME_LABEL(ret_from_exception)
bnes 2f | if so, skip resched, signals
tstl SYMBOL_NAME(need_resched)
jne SYMBOL_NAME(reschedule)
- movel SYMBOL_NAME(current_set),%a0
- cmpl #SYMBOL_NAME(task),%a0 | task[0] cannot have signals
+ cmpl #SYMBOL_NAME(task),%curptr | task[0] cannot have signals
jeq 2f
- bclr #5,%a0@(LTASK_FLAGS+1) | check for delayed trace
+ bclr #5,%curptr@(LTASK_FLAGS+1) | check for delayed trace
jne do_delayed_trace
5:
- tstl %a0@(LTASK_STATE) | state
+ tstl %curptr@(LTASK_STATE) | state
jne SYMBOL_NAME(reschedule)
- tstl %a0@(LTASK_COUNTER) | counter
+ tstl %curptr@(LTASK_COUNTER) | counter
jeq SYMBOL_NAME(reschedule)
- movel %a0@(LTASK_BLOCKED),%d0
+ movel %curptr@(LTASK_BLOCKED),%d0
movel %d0,%d1 | save blocked in d1 for sig handling
notl %d0
- btst #4,%a0@(LTASK_FLAGS+3) | PF_PTRACED
+ btst #4,%curptr@(LTASK_FLAGS+3) | PF_PTRACED
jeq 1f
moveq #-1,%d0 | let the debugger see all signals
-1: andl %a0@(LTASK_SIGNAL),%d0
+1: andl %curptr@(LTASK_SIGNAL),%d0
jne Lsignal_return
2: RESTORE_ALL
@@ -248,7 +262,6 @@ do_delayed_trace:
jbsr SYMBOL_NAME(send_sig)
addql #8,%sp
addql #4,%sp
- movel SYMBOL_NAME(current_set),%a0
jra 5b
/*
@@ -260,6 +273,7 @@ SYMBOL_NAME_LABEL(inthandler)
movel %d0,%sp@(LORIG_D0) | a -1 in the ORIG_D0 field
| signifies that the stack frame
| is NOT for syscall
+ GET_CURRENT(%d0)
addql #1,SYMBOL_NAME(local_irq_count)
| put exception # in d0
bfextu %sp@(LFORMATVEC){#4,#10},%d0
@@ -270,28 +284,31 @@ SYMBOL_NAME_LABEL(inthandler)
addql #8,%sp | pop parameters off stack
SYMBOL_NAME_LABEL(ret_from_interrupt)
- /* check if we need to do software interrupts */
- movel SYMBOL_NAME(local_irq_count),%d1
- subql #1,%d1
- jne 4f
-#if 0
- bfextu %sp@(LSR){#5,#3},%d0 | Check for nested interrupt.
+ subql #1,SYMBOL_NAME(local_irq_count)
+ jeq 1f
+2:
+ RESTORE_ALL
+1:
+#if 1
+ bfextu %sp@(LSR){#5,#3},%d0 | Check for nested interrupt.
#if MAX_NOINT_IPL > 0
cmpiw #MAX_NOINT_IPL,%d0
#endif
- jhi 4f
+ jhi 2b
#endif
+ /* Let the rest run with interrupts allowed. This is safe since
+ the kernel never uses a non-standard ipl and this is the outer
+ level interrupt. */
+ andw #ALLOWINT,%sr
+
+ /* check if we need to do software interrupts */
+
movel SYMBOL_NAME(bh_active),%d0
andl SYMBOL_NAME(bh_mask),%d0
- jeq 3f
+ jeq SYMBOL_NAME(ret_from_exception)
- jbsr SYMBOL_NAME(do_bottom_half)
-3:
- clrl SYMBOL_NAME(local_irq_count)
- jra SYMBOL_NAME(ret_from_exception)
-4:
- movel %d1,SYMBOL_NAME(local_irq_count)
- RESTORE_ALL
+ pea SYMBOL_NAME(ret_from_exception)
+ jra SYMBOL_NAME(do_bottom_half)
/* Handler for uninitialized and spurious interrupts */
@@ -398,7 +415,7 @@ SYMBOL_NAME_LABEL(resume)
3:
/* get pointer to tss struct (a1 contains new task) */
- movel %a1,SYMBOL_NAME(current_set)
+ movel %a1,%curptr
addl %d1,%a1
/* Skip address space switching if they are the same. */
@@ -419,7 +436,7 @@ SYMBOL_NAME_LABEL(resume)
movec %cacr,%d0
oriw #LFLUSH_I_AND_D,%d0
movec %d0,%cacr
-
+
/* switch the root pointer */
pmove %a1@(LTSS_CRP),%crp
#endif
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-09 22:31:40 +0000