kernel-ark/include/asm-m32r/sigcontext.h
Hirokazu Takata 8e8ff02c0b [PATCH] m32r: Fix pt_regs for !COFNIG_ISA_DSP_LEVEL2 target
This modification is required to fix debugging function for m32r targets
with !CONFIG_ISA_DSP_LEVEL2, by unifying 'struct pt_regs' and 'struct
sigcontext' size for all M32R ISA.

Some m32r processor core with !CONFIG_ISA_DSP_LEVEL2 configuration has only
single accumulator a0 (ex.  VDEC2 core, M32102 core, etc.), the others with
CONFIG_ISA_DSP_LEVEL2 has two accumulators, a0 and a1.

This means there are two variations of thread context.  So far, we reduced
and changed stackframe size at a syscall for their context size.  However,
this causes a problem that a GDB for processors with CONFIG_ISA_DSP_LEVEL2
cannot be used for processors with !CONFIG_ISA_DSP_LEVEL2.

From the viewpoint of GDB support, we should reduce such variation of
stackframe size for simplicity.

In this patch, dummy members are added to 'struct pt_regs' and 'struct
sigcontext' to adjust their size for !CONFIG_ISA_DSP_LEVEL2.

This modification is also a one step for a GDB update in future.
Currently, on the m32r, GDB can access process's context by using ptrace
functions in a simple way of register by register access.  By unifying
stackframe size, we have a possibility to make use of ptrace functions of
not only a single register access but also block register access,
PTRACE_{GETREGS,PUTREGS}.

However, for this purpose, we might have to modify stackframe structure
some more; for example, PSW (processor status word) register should be
pre-processed before pushing to stack at a syscall, and so on.  In this
case, we must update carefully both kernel and GDB at a time...

Signed-off-by: Hayato Fujiwara <fujiwara@linux-m32r.org>
Signed-off-by: Hirokazu Takata <takata@linux-m32r.org>
Cc: Kei Sakamoto <ksakamot@linux-m32r.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-04-19 09:13:50 -07:00

53 lines
1.3 KiB
C

#ifndef _ASM_M32R_SIGCONTEXT_H
#define _ASM_M32R_SIGCONTEXT_H
/* $Id$ */
#include <linux/config.h>
struct sigcontext {
/* CPU registers */
/* Saved main processor registers. */
unsigned long sc_r4;
unsigned long sc_r5;
unsigned long sc_r6;
struct pt_regs *sc_pt_regs;
unsigned long sc_r0;
unsigned long sc_r1;
unsigned long sc_r2;
unsigned long sc_r3;
unsigned long sc_r7;
unsigned long sc_r8;
unsigned long sc_r9;
unsigned long sc_r10;
unsigned long sc_r11;
unsigned long sc_r12;
/* Saved main processor status and miscellaneous context registers. */
#if defined(CONFIG_ISA_M32R2) && defined(CONFIG_ISA_DSP_LEVEL2)
unsigned long sc_acc0h;
unsigned long sc_acc0l;
unsigned long sc_acc1h;
unsigned long sc_acc1l;
#elif defined(CONFIG_ISA_M32R2) || defined(CONFIG_ISA_M32R)
unsigned long sc_acch;
unsigned long sc_accl;
unsigned long sc_dummy_acc1h;
unsigned long sc_dummy_acc1l;
#else
#error unknown isa configuration
#endif
unsigned long sc_psw;
unsigned long sc_bpc; /* saved PC for TRAP syscalls */
unsigned long sc_bbpsw;
unsigned long sc_bbpc;
unsigned long sc_spu; /* saved user stack */
unsigned long sc_fp;
unsigned long sc_lr; /* saved PC for JL syscalls */
unsigned long sc_spi; /* saved kernel stack */
unsigned long oldmask;
};
#endif /* _ASM_M32R_SIGCONTEXT_H */