sparc: Add kgdb support.
Current limitations:
1) On SMP single stepping has some fundamental issues,
shared with other sw single-step architectures such
as mips and arm.
2) On 32-bit sparc we don't support SMP kgdb yet. That
requires some reworking of the IPI mechanisms and
infrastructure on that platform.
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/arch/sparc/kernel/entry.S b/arch/sparc/kernel/entry.S
index 484c83d..57d1bbd 100644
--- a/arch/sparc/kernel/entry.S
+++ b/arch/sparc/kernel/entry.S
@@ -12,7 +12,6 @@
#include <asm/head.h>
#include <asm/asi.h>
#include <asm/smp.h>
-#include <asm/kgdb.h>
#include <asm/contregs.h>
#include <asm/ptrace.h>
#include <asm/asm-offsets.h>
@@ -45,91 +44,20 @@
_SV; _SV; _SV; _SV; _SV; _SV; _SV; \
_RS; _RS; _RS; _RS; _RS; _RS; _RS;
-/* First, KGDB low level things. This is a rewrite
- * of the routines found in the sparc-stub.c asm() statement
- * from the gdb distribution. This is also dual-purpose
- * as a software trap for userlevel programs.
- */
- .data
- .align 4
-
-in_trap_handler:
- .word 0
-
.text
+
+#ifdef CONFIG_KGDB
.align 4
-
-#if 0 /* kgdb is dropped from 2.5.33 */
-! This function is called when any SPARC trap (except window overflow or
-! underflow) occurs. It makes sure that the invalid register window is still
-! available before jumping into C code. It will also restore the world if you
-! return from handle_exception.
-
- .globl trap_low
-trap_low:
- rd %wim, %l3
- SAVE_ALL
-
- sethi %hi(in_trap_handler), %l4
- ld [%lo(in_trap_handler) + %l4], %l5
- inc %l5
- st %l5, [%lo(in_trap_handler) + %l4]
-
- /* Make sure kgdb sees the same state we just saved. */
- LOAD_PT_GLOBALS(sp)
- LOAD_PT_INS(sp)
- ld [%sp + STACKFRAME_SZ + PT_Y], %l4
- ld [%sp + STACKFRAME_SZ + PT_WIM], %l3
- ld [%sp + STACKFRAME_SZ + PT_PSR], %l0
- ld [%sp + STACKFRAME_SZ + PT_PC], %l1
- ld [%sp + STACKFRAME_SZ + PT_NPC], %l2
- rd %tbr, %l5 /* Never changes... */
-
- /* Make kgdb exception frame. */
- sub %sp,(16+1+6+1+72)*4,%sp ! Make room for input & locals
- ! + hidden arg + arg spill
- ! + doubleword alignment
- ! + registers[72] local var
- SAVE_KGDB_GLOBALS(sp)
- SAVE_KGDB_INS(sp)
- SAVE_KGDB_SREGS(sp, l4, l0, l3, l5, l1, l2)
-
- /* We are increasing PIL, so two writes. */
- or %l0, PSR_PIL, %l0
- wr %l0, 0, %psr
- WRITE_PAUSE
- wr %l0, PSR_ET, %psr
- WRITE_PAUSE
-
- call handle_exception
- add %sp, STACKFRAME_SZ, %o0 ! Pass address of registers
-
- /* Load new kgdb register set. */
- LOAD_KGDB_GLOBALS(sp)
- LOAD_KGDB_INS(sp)
- LOAD_KGDB_SREGS(sp, l4, l0, l3, l5, l1, l2)
- wr %l4, 0x0, %y
-
- sethi %hi(in_trap_handler), %l4
- ld [%lo(in_trap_handler) + %l4], %l5
- dec %l5
- st %l5, [%lo(in_trap_handler) + %l4]
-
- add %sp,(16+1+6+1+72)*4,%sp ! Undo the kgdb trap frame.
-
- /* Now take what kgdb did and place it into the pt_regs
- * frame which SparcLinux RESTORE_ALL understands.,
- */
- STORE_PT_INS(sp)
- STORE_PT_GLOBALS(sp)
- STORE_PT_YREG(sp, g2)
- STORE_PT_PRIV(sp, l0, l1, l2)
-
- RESTORE_ALL
+ .globl arch_kgdb_breakpoint
+ .type arch_kgdb_breakpoint,#function
+arch_kgdb_breakpoint:
+ ta 0x7d
+ retl
+ nop
+ .size arch_kgdb_breakpoint,.-arch_kgdb_breakpoint
#endif
#if defined(CONFIG_BLK_DEV_FD) || defined(CONFIG_BLK_DEV_FD_MODULE)
- .text
.align 4
.globl floppy_hardint
floppy_hardint:
@@ -1596,6 +1524,23 @@
RESTORE_ALL
+#ifdef CONFIG_KGDB
+ .align 4
+ .globl kgdb_trap_low
+ .type kgdb_trap_low,#function
+kgdb_trap_low:
+ rd %wim,%l3
+ SAVE_ALL
+ wr %l0, PSR_ET, %psr
+ WRITE_PAUSE
+
+ call kgdb_trap
+ add %sp, STACKFRAME_SZ, %o0
+
+ RESTORE_ALL
+ .size kgdb_trap_low,.-kgdb_trap_low
+#endif
+
.align 4
.globl __handle_exception, flush_patch_exception
__handle_exception:
@@ -1698,4 +1643,22 @@
#endif /* CONFIG_PCI */
+ .globl flushw_all
+flushw_all:
+ save %sp, -0x40, %sp
+ save %sp, -0x40, %sp
+ save %sp, -0x40, %sp
+ save %sp, -0x40, %sp
+ save %sp, -0x40, %sp
+ save %sp, -0x40, %sp
+ save %sp, -0x40, %sp
+ restore
+ restore
+ restore
+ restore
+ restore
+ restore
+ ret
+ restore
+
/* End of entry.S */