From 733536b865441d9bad02c4711a4372d48ce21e54 Mon Sep 17 00:00:00 2001 From: Max Filippov Date: Thu, 15 Nov 2012 06:25:48 +0400 Subject: [PATCH] xtensa: save and restore scompare1 SR on kernel entry Although scompare1 may be saved/restored by xchal_ncp_{load,store} macros, explicit save/restore of registers manipulated by the kernel itself is considered more correct. Signed-off-by: Max Filippov Signed-off-by: Chris Zankel --- arch/xtensa/include/asm/ptrace.h | 2 +- arch/xtensa/kernel/asm-offsets.c | 1 + arch/xtensa/kernel/entry.S | 13 +++++++++++++ 3 files changed, 15 insertions(+), 1 deletion(-) diff --git a/arch/xtensa/include/asm/ptrace.h b/arch/xtensa/include/asm/ptrace.h index da21c17..9fe249c 100644 --- a/arch/xtensa/include/asm/ptrace.h +++ b/arch/xtensa/include/asm/ptrace.h @@ -37,7 +37,7 @@ struct pt_regs { unsigned long windowstart; /* 52 */ unsigned long syscall; /* 56 */ unsigned long icountlevel; /* 60 */ - int reserved[1]; /* 64 */ + unsigned long scompare1; /* 64 */ /* Additional configurable registers that are used by the compiler. */ xtregs_opt_t xtregs_opt; diff --git a/arch/xtensa/kernel/asm-offsets.c b/arch/xtensa/kernel/asm-offsets.c index 7dc3f91..845475a 100644 --- a/arch/xtensa/kernel/asm-offsets.c +++ b/arch/xtensa/kernel/asm-offsets.c @@ -41,6 +41,7 @@ int main(void) DEFINE(PT_SAR, offsetof (struct pt_regs, sar)); DEFINE(PT_ICOUNTLEVEL, offsetof (struct pt_regs, icountlevel)); DEFINE(PT_SYSCALL, offsetof (struct pt_regs, syscall)); + DEFINE(PT_SCOMPARE1, offsetof(struct pt_regs, scompare1)); DEFINE(PT_AREG, offsetof (struct pt_regs, areg[0])); DEFINE(PT_AREG0, offsetof (struct pt_regs, areg[0])); DEFINE(PT_AREG1, offsetof (struct pt_regs, areg[1])); diff --git a/arch/xtensa/kernel/entry.S b/arch/xtensa/kernel/entry.S index 41ad9cf..4c2f270 100644 --- a/arch/xtensa/kernel/entry.S +++ b/arch/xtensa/kernel/entry.S @@ -372,6 +372,13 @@ common_exception: s32i a2, a1, PT_LBEG s32i a3, a1, PT_LEND + /* Save SCOMPARE1 */ + +#if XCHAL_HAVE_S32C1I + rsr a2, scompare1 + s32i a2, a1, PT_SCOMPARE1 +#endif + /* Save optional registers. */ save_xtregs_opt a1 a2 a4 a5 a6 a7 PT_XTREGS_OPT @@ -433,6 +440,12 @@ common_exception_return: load_xtregs_opt a1 a2 a4 a5 a6 a7 PT_XTREGS_OPT + /* Restore SCOMPARE1 */ + +#if XCHAL_HAVE_S32C1I + l32i a2, a1, PT_SCOMPARE1 + wsr a2, scompare1 +#endif wsr a3, ps /* disable interrupts */ _bbci.l a3, PS_UM_BIT, kernel_exception_exit -- 2.7.4