diff options
author | Steven J. Hill <Steven.Hill@imgtec.com> | 2013-03-25 17:15:55 (GMT) |
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committer | Ralf Baechle <ralf@linux-mips.org> | 2013-05-09 15:55:18 (GMT) |
commit | 2a0b24f56c2492b932f1aed617ae80fb23500d21 (patch) | |
tree | c9aec2872f912c65b83a92a66fe94f6006427d73 /arch/mips/kernel/genex.S | |
parent | 102cedc32a6e3cd537374a3678d407591d5a6fab (diff) | |
download | linux-2a0b24f56c2492b932f1aed617ae80fb23500d21.tar.xz |
MIPS: microMIPS: Add support for exception handling.
All exceptions must be taken in microMIPS mode, never in classic
MIPS mode or the kernel falls apart. A few NOP instructions are
used to maintain the correct alignment of microMIPS versions of
the exception vectors.
Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com>
Diffstat (limited to 'arch/mips/kernel/genex.S')
-rw-r--r-- | arch/mips/kernel/genex.S | 73 |
1 files changed, 54 insertions, 19 deletions
diff --git a/arch/mips/kernel/genex.S b/arch/mips/kernel/genex.S index 5360b1d..5c2ba9f 100644 --- a/arch/mips/kernel/genex.S +++ b/arch/mips/kernel/genex.S @@ -5,8 +5,8 @@ * * Copyright (C) 1994 - 2000, 2001, 2003 Ralf Baechle * Copyright (C) 1999, 2000 Silicon Graphics, Inc. - * Copyright (C) 2001 MIPS Technologies, Inc. * Copyright (C) 2002, 2007 Maciej W. Rozycki + * Copyright (C) 2001, 2012 MIPS Technologies, Inc. All rights reserved. */ #include <linux/init.h> @@ -21,8 +21,10 @@ #include <asm/war.h> #include <asm/thread_info.h> +#ifdef CONFIG_MIPS_MT_SMTC #define PANIC_PIC(msg) \ - .set push; \ + .set push; \ + .set nomicromips; \ .set reorder; \ PTR_LA a0,8f; \ .set noat; \ @@ -31,17 +33,10 @@ 9: b 9b; \ .set pop; \ TEXT(msg) +#endif __INIT -NESTED(except_vec0_generic, 0, sp) - PANIC_PIC("Exception vector 0 called") - END(except_vec0_generic) - -NESTED(except_vec1_generic, 0, sp) - PANIC_PIC("Exception vector 1 called") - END(except_vec1_generic) - /* * General exception vector for all other CPUs. * @@ -138,12 +133,19 @@ LEAF(r4k_wait) nop nop nop +#ifdef CONFIG_CPU_MICROMIPS + nop + nop + nop + nop +#endif .set mips3 wait /* end of rollback region (the region size must be power of two) */ - .set pop 1: jr ra + nop + .set pop END(r4k_wait) .macro BUILD_ROLLBACK_PROLOGUE handler @@ -201,7 +203,11 @@ NESTED(handle_int, PT_SIZE, sp) LONG_L s0, TI_REGS($28) LONG_S sp, TI_REGS($28) PTR_LA ra, ret_from_irq - j plat_irq_dispatch + PTR_LA v0, plat_irq_dispatch + jr v0 +#ifdef CONFIG_CPU_MICROMIPS + nop +#endif END(handle_int) __INIT @@ -222,11 +228,14 @@ NESTED(except_vec4, 0, sp) /* * EJTAG debug exception handler. * The EJTAG debug exception entry point is 0xbfc00480, which - * normally is in the boot PROM, so the boot PROM must do a + * normally is in the boot PROM, so the boot PROM must do an * unconditional jump to this vector. */ NESTED(except_vec_ejtag_debug, 0, sp) j ejtag_debug_handler +#ifdef CONFIG_CPU_MICROMIPS + nop +#endif END(except_vec_ejtag_debug) __FINIT @@ -251,9 +260,10 @@ NESTED(except_vec_vi, 0, sp) FEXPORT(except_vec_vi_mori) ori a0, $0, 0 #endif /* CONFIG_MIPS_MT_SMTC */ + PTR_LA v1, except_vec_vi_handler FEXPORT(except_vec_vi_lui) lui v0, 0 /* Patched */ - j except_vec_vi_handler + jr v1 FEXPORT(except_vec_vi_ori) ori v0, 0 /* Patched */ .set pop @@ -354,6 +364,9 @@ EXPORT(ejtag_debug_buffer) */ NESTED(except_vec_nmi, 0, sp) j nmi_handler +#ifdef CONFIG_CPU_MICROMIPS + nop +#endif END(except_vec_nmi) __FINIT @@ -500,13 +513,35 @@ NESTED(nmi_handler, PT_SIZE, sp) .set push .set noat .set noreorder - /* 0x7c03e83b: rdhwr v1,$29 */ + /* MIPS32: 0x7c03e83b: rdhwr v1,$29 */ + /* microMIPS: 0x007d6b3c: rdhwr v1,$29 */ MFC0 k1, CP0_EPC - lui k0, 0x7c03 - lw k1, (k1) - ori k0, 0xe83b - .set reorder +#if defined(CONFIG_CPU_MICROMIPS) || defined(CONFIG_CPU_MIPS32_R2) || defined(CONFIG_CPU_MIPS64_R2) + and k0, k1, 1 + beqz k0, 1f + xor k1, k0 + lhu k0, (k1) + lhu k1, 2(k1) + ins k1, k0, 16, 16 + lui k0, 0x007d + b docheck + ori k0, 0x6b3c +1: + lui k0, 0x7c03 + lw k1, (k1) + ori k0, 0xe83b +#else + andi k0, k1, 1 + bnez k0, handle_ri + lui k0, 0x7c03 + lw k1, (k1) + ori k0, 0xe83b +#endif + .set reorder +docheck: bne k0, k1, handle_ri /* if not ours */ + +isrdhwr: /* The insn is rdhwr. No need to check CAUSE.BD here. */ get_saved_sp /* k1 := current_thread_info */ .set noreorder |