From 0b930489b8606224b829c8a6037eac24249a97ec Mon Sep 17 00:00:00 2001 From: Matt Fleming Date: Sun, 2 Aug 2009 22:33:26 +0100 Subject: [PATCH] sh: Setup the frame register in asm code In order to use DWARF unwinder info the frame register has to contain a valid value. Whilst GCC takes care of this for C code, we have to do it ourselves for assembly. Signed-off-by: Matt Fleming Signed-off-by: Paul Mundt --- arch/sh/include/asm/entry-macros.S | 12 ++++++++++++ arch/sh/kernel/cpu/sh3/entry.S | 1 + arch/sh/kernel/entry-common.S | 1 + 3 files changed, 14 insertions(+) diff --git a/arch/sh/include/asm/entry-macros.S b/arch/sh/include/asm/entry-macros.S index 1bdd938..64fd0de 100644 --- a/arch/sh/include/asm/entry-macros.S +++ b/arch/sh/include/asm/entry-macros.S @@ -108,3 +108,15 @@ #else # define PREF(x) nop #endif + + /* + * Macro for use within assembly. Because the DWARF unwinder + * needs to use the frame register to unwind the stack, we + * need to setup r14 with the value of the stack pointer as + * the return address is usually on the stack somewhere. + */ + .macro setup_frame_reg +#ifdef CONFIG_DWARF_UNWINDER + mov r15, r14 +#endif + .endm diff --git a/arch/sh/kernel/cpu/sh3/entry.S b/arch/sh/kernel/cpu/sh3/entry.S index 3cb531f..67ad646 100644 --- a/arch/sh/kernel/cpu/sh3/entry.S +++ b/arch/sh/kernel/cpu/sh3/entry.S @@ -137,6 +137,7 @@ ENTRY(tlb_protection_violation_store) mov #1, r5 call_dpf: + setup_frame_reg mov.l 1f, r0 mov r5, r8 mov.l @r0, r6 diff --git a/arch/sh/kernel/entry-common.S b/arch/sh/kernel/entry-common.S index fc26ccd..b3b215f 100644 --- a/arch/sh/kernel/entry-common.S +++ b/arch/sh/kernel/entry-common.S @@ -285,6 +285,7 @@ ret_from_fork: * system calls and debug traps through their respective jump tables. */ ENTRY(system_call) + setup_frame_reg #if !defined(CONFIG_CPU_SH2) mov.l 1f, r9 mov.l @r9, r8 ! Read from TRA (Trap Address) Register -- 1.8.2.3