diff options
| -rw-r--r-- | arch/powerpc/include/asm/machdep.h | 1 | ||||
| -rw-r--r-- | arch/powerpc/kernel/Makefile | 2 | ||||
| -rw-r--r-- | arch/powerpc/kernel/exceptions-64e.S | 23 | ||||
| -rw-r--r-- | arch/powerpc/kernel/idle_book3e.S | 86 |
4 files changed, 111 insertions, 1 deletions
diff --git a/arch/powerpc/include/asm/machdep.h b/arch/powerpc/include/asm/machdep.h index 2bad6e5..adc8e6c 100644 --- a/arch/powerpc/include/asm/machdep.h +++ b/arch/powerpc/include/asm/machdep.h @@ -278,6 +278,7 @@ extern void e500_idle(void); extern void power4_idle(void); extern void power4_cpu_offline_powersave(void); extern void ppc6xx_idle(void); +extern void book3e_idle(void); /* * ppc_md contains a copy of the machine description structure for the diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile index 8a33318..77d831a 100644 --- a/arch/powerpc/kernel/Makefile +++ b/arch/powerpc/kernel/Makefile @@ -37,7 +37,7 @@ obj-$(CONFIG_PPC64) += setup_64.o sys_ppc32.o \ obj-$(CONFIG_HAVE_HW_BREAKPOINT) += hw_breakpoint.o obj-$(CONFIG_PPC_BOOK3S_64) += cpu_setup_ppc970.o cpu_setup_pa6t.o obj64-$(CONFIG_RELOCATABLE) += reloc_64.o -obj-$(CONFIG_PPC_BOOK3E_64) += exceptions-64e.o +obj-$(CONFIG_PPC_BOOK3E_64) += exceptions-64e.o idle_book3e.o obj-$(CONFIG_PPC64) += vdso64/ obj-$(CONFIG_ALTIVEC) += vecemu.o obj-$(CONFIG_PPC_970_NAP) += idle_power4.o diff --git a/arch/powerpc/kernel/exceptions-64e.S b/arch/powerpc/kernel/exceptions-64e.S index a42637c..316465a 100644 --- a/arch/powerpc/kernel/exceptions-64e.S +++ b/arch/powerpc/kernel/exceptions-64e.S @@ -204,11 +204,30 @@ exc_##n##_bad_stack: \ lis r,TSR_FIS@h; \ mtspr SPRN_TSR,r +/* Used by asynchronous interrupt that may happen in the idle loop. + * + * This check if the thread was in the idle loop, and if yes, returns + * to the caller rather than the PC. This is to avoid a race if + * interrupts happen before the wait instruction. + */ +#define CHECK_NAPPING() \ + clrrdi r11,r1,THREAD_SHIFT; \ + ld r10,TI_LOCAL_FLAGS(r11); \ + andi. r9,r10,_TLF_NAPPING; \ + beq+ 1f; \ + ld r8,_LINK(r1); \ + rlwinm r7,r10,0,~_TLF_NAPPING; \ + std r8,_NIP(r1); \ + std r7,TI_LOCAL_FLAGS(r11); \ +1: + + #define MASKABLE_EXCEPTION(trapnum, label, hdlr, ack) \ START_EXCEPTION(label); \ NORMAL_EXCEPTION_PROLOG(trapnum, PROLOG_ADDITION_MASKABLE) \ EXCEPTION_COMMON(trapnum, PACA_EXGEN, INTS_DISABLE_ALL) \ ack(r8); \ + CHECK_NAPPING(); \ addi r3,r1,STACK_FRAME_OVERHEAD; \ bl hdlr; \ b .ret_from_except_lite; @@ -257,6 +276,7 @@ interrupt_end_book3e: CRIT_EXCEPTION_PROLOG(0x100, PROLOG_ADDITION_NONE) // EXCEPTION_COMMON(0x100, PACA_EXCRIT, INTS_DISABLE_ALL) // bl special_reg_save_crit +// CHECK_NAPPING(); // addi r3,r1,STACK_FRAME_OVERHEAD // bl .critical_exception // b ret_from_crit_except @@ -268,6 +288,7 @@ interrupt_end_book3e: // EXCEPTION_COMMON(0x200, PACA_EXMC, INTS_DISABLE_ALL) // bl special_reg_save_mc // addi r3,r1,STACK_FRAME_OVERHEAD +// CHECK_NAPPING(); // bl .machine_check_exception // b ret_from_mc_except b . @@ -338,6 +359,7 @@ interrupt_end_book3e: CRIT_EXCEPTION_PROLOG(0x9f0, PROLOG_ADDITION_NONE) // EXCEPTION_COMMON(0x9f0, PACA_EXCRIT, INTS_DISABLE_ALL) // bl special_reg_save_crit +// CHECK_NAPPING(); // addi r3,r1,STACK_FRAME_OVERHEAD // bl .unknown_exception // b ret_from_crit_except @@ -434,6 +456,7 @@ kernel_dbg_exc: CRIT_EXCEPTION_PROLOG(0x2080, PROLOG_ADDITION_NONE) // EXCEPTION_COMMON(0x2080, PACA_EXCRIT, INTS_DISABLE_ALL) // bl special_reg_save_crit +// CHECK_NAPPING(); // addi r3,r1,STACK_FRAME_OVERHEAD // bl .doorbell_critical_exception // b ret_from_crit_except diff --git a/arch/powerpc/kernel/idle_book3e.S b/arch/powerpc/kernel/idle_book3e.S new file mode 100644 index 0000000..16c002d --- /dev/null +++ b/arch/powerpc/kernel/idle_book3e.S @@ -0,0 +1,86 @@ +/* + * Copyright 2010 IBM Corp, Benjamin Herrenschmidt <benh@kernel.crashing.org> + * + * Generic idle routine for Book3E processors + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +#include <linux/threads.h> +#include <asm/reg.h> +#include <asm/ppc_asm.h> +#include <asm/asm-offsets.h> +#include <asm/ppc-opcode.h> +#include <asm/processor.h> +#include <asm/thread_info.h> + +/* 64-bit version only for now */ +#ifdef CONFIG_PPC64 + +_GLOBAL(book3e_idle) + /* Save LR for later */ + mflr r0 + std r0,16(r1) + + /* Hard disable interrupts */ + wrteei 0 + + /* Now check if an interrupt came in while we were soft disabled + * since we may otherwise lose it (doorbells etc...). We know + * that since PACAHARDIRQEN will have been cleared in that case. + */ + lbz r3,PACAHARDIRQEN(r13) + cmpwi cr0,r3,0 + beqlr + + /* Now we are going to mark ourselves as soft and hard enables in + * order to be able to take interrupts while asleep. We inform lockdep + * of that. We don't actually turn interrupts on just yet tho. + */ +#ifdef CONFIG_TRACE_IRQFLAGS + stdu r1,-128(r1) + bl .trace_hardirqs_on +#endif + li r0,1 + stb r0,PACASOFTIRQEN(r13) + stb r0,PACAHARDIRQEN(r13) + + /* Interrupts will make use return to LR, so get something we want + * in there + */ + bl 1f + + /* Hard disable interrupts again */ + wrteei 0 + + /* Mark them off again in the PACA as well */ + li r0,0 + stb r0,PACASOFTIRQEN(r13) + stb r0,PACAHARDIRQEN(r13) + + /* Tell lockdep about it */ +#ifdef CONFIG_TRACE_IRQFLAGS + bl .trace_hardirqs_off + addi r1,r1,128 +#endif + ld r0,16(r1) + mtlr r0 + blr + +1: /* Let's set the _TLF_NAPPING flag so interrupts make us return + * to the right spot + */ + clrrdi r11,r1,THREAD_SHIFT + ld r10,TI_LOCAL_FLAGS(r11) + ori r10,r10,_TLF_NAPPING + std r10,TI_LOCAL_FLAGS(r11) + + /* We can now re-enable hard interrupts and go to sleep */ + wrteei 1 +1: PPC_WAIT(0) + b 1b + +#endif /* CONFIG_PPC64 */ |