diff options
Diffstat (limited to 'arch/mips/kernel/process.c')
| -rw-r--r-- | arch/mips/kernel/process.c | 184 |
1 files changed, 143 insertions, 41 deletions
diff --git a/arch/mips/kernel/process.c b/arch/mips/kernel/process.c index 3be4405c2d14..c6a041d9d05d 100644 --- a/arch/mips/kernel/process.c +++ b/arch/mips/kernel/process.c @@ -7,6 +7,7 @@ * Copyright (C) 2005, 2006 by Ralf Baechle (ralf@linux-mips.org) * Copyright (C) 1999, 2000 Silicon Graphics, Inc. * Copyright (C) 2004 Thiemo Seufer + * Copyright (C) 2013 Imagination Technologies Ltd. */ #include <linux/errno.h> #include <linux/sched.h> @@ -41,45 +42,14 @@ #include <asm/inst.h> #include <asm/stacktrace.h> -/* - * The idle thread. There's no useful work to be done, so just try to conserve - * power and have a low exit latency (ie sit in a loop waiting for somebody to - * say that they'd like to reschedule) - */ -void __noreturn cpu_idle(void) -{ - int cpu; - - /* CPU is going idle. */ - cpu = smp_processor_id(); - - /* endless idle loop with no priority at all */ - while (1) { - tick_nohz_idle_enter(); - rcu_idle_enter(); - while (!need_resched() && cpu_online(cpu)) { -#ifdef CONFIG_MIPS_MT_SMTC - extern void smtc_idle_loop_hook(void); - - smtc_idle_loop_hook(); -#endif - - if (cpu_wait) { - /* Don't trace irqs off for idle */ - stop_critical_timings(); - (*cpu_wait)(); - start_critical_timings(); - } - } #ifdef CONFIG_HOTPLUG_CPU - if (!cpu_online(cpu) && !cpu_isset(cpu, cpu_callin_map)) - play_dead(); -#endif - rcu_idle_exit(); - tick_nohz_idle_exit(); - schedule_preempt_disabled(); - } +void arch_cpu_idle_dead(void) +{ + /* What the heck is this check doing ? */ + if (!cpu_isset(smp_processor_id(), cpu_callin_map)) + play_dead(); } +#endif asmlinkage void ret_from_fork(void); asmlinkage void ret_from_kernel_thread(void); @@ -241,36 +211,122 @@ struct mips_frame_info { int pc_offset; }; +#define J_TARGET(pc,target) \ + (((unsigned long)(pc) & 0xf0000000) | ((target) << 2)) + static inline int is_ra_save_ins(union mips_instruction *ip) { +#ifdef CONFIG_CPU_MICROMIPS + union mips_instruction mmi; + + /* + * swsp ra,offset + * swm16 reglist,offset(sp) + * swm32 reglist,offset(sp) + * sw32 ra,offset(sp) + * jradiussp - NOT SUPPORTED + * + * microMIPS is way more fun... + */ + if (mm_insn_16bit(ip->halfword[0])) { + mmi.word = (ip->halfword[0] << 16); + return ((mmi.mm16_r5_format.opcode == mm_swsp16_op && + mmi.mm16_r5_format.rt == 31) || + (mmi.mm16_m_format.opcode == mm_pool16c_op && + mmi.mm16_m_format.func == mm_swm16_op)); + } + else { + mmi.halfword[0] = ip->halfword[1]; + mmi.halfword[1] = ip->halfword[0]; + return ((mmi.mm_m_format.opcode == mm_pool32b_op && + mmi.mm_m_format.rd > 9 && + mmi.mm_m_format.base == 29 && + mmi.mm_m_format.func == mm_swm32_func) || + (mmi.i_format.opcode == mm_sw32_op && + mmi.i_format.rs == 29 && + mmi.i_format.rt == 31)); + } +#else /* sw / sd $ra, offset($sp) */ return (ip->i_format.opcode == sw_op || ip->i_format.opcode == sd_op) && ip->i_format.rs == 29 && ip->i_format.rt == 31; +#endif } -static inline int is_jal_jalr_jr_ins(union mips_instruction *ip) +static inline int is_jump_ins(union mips_instruction *ip) { +#ifdef CONFIG_CPU_MICROMIPS + /* + * jr16,jrc,jalr16,jalr16 + * jal + * jalr/jr,jalr.hb/jr.hb,jalrs,jalrs.hb + * jraddiusp - NOT SUPPORTED + * + * microMIPS is kind of more fun... + */ + union mips_instruction mmi; + + mmi.word = (ip->halfword[0] << 16); + + if ((mmi.mm16_r5_format.opcode == mm_pool16c_op && + (mmi.mm16_r5_format.rt & mm_jr16_op) == mm_jr16_op) || + ip->j_format.opcode == mm_jal32_op) + return 1; + if (ip->r_format.opcode != mm_pool32a_op || + ip->r_format.func != mm_pool32axf_op) + return 0; + return (((ip->u_format.uimmediate >> 6) & mm_jalr_op) == mm_jalr_op); +#else + if (ip->j_format.opcode == j_op) + return 1; if (ip->j_format.opcode == jal_op) return 1; if (ip->r_format.opcode != spec_op) return 0; return ip->r_format.func == jalr_op || ip->r_format.func == jr_op; +#endif } static inline int is_sp_move_ins(union mips_instruction *ip) { +#ifdef CONFIG_CPU_MICROMIPS + /* + * addiusp -imm + * addius5 sp,-imm + * addiu32 sp,sp,-imm + * jradiussp - NOT SUPPORTED + * + * microMIPS is not more fun... + */ + if (mm_insn_16bit(ip->halfword[0])) { + union mips_instruction mmi; + + mmi.word = (ip->halfword[0] << 16); + return ((mmi.mm16_r3_format.opcode == mm_pool16d_op && + mmi.mm16_r3_format.simmediate && mm_addiusp_func) || + (mmi.mm16_r5_format.opcode == mm_pool16d_op && + mmi.mm16_r5_format.rt == 29)); + } + return (ip->mm_i_format.opcode == mm_addiu32_op && + ip->mm_i_format.rt == 29 && ip->mm_i_format.rs == 29); +#else /* addiu/daddiu sp,sp,-imm */ if (ip->i_format.rs != 29 || ip->i_format.rt != 29) return 0; if (ip->i_format.opcode == addiu_op || ip->i_format.opcode == daddiu_op) return 1; +#endif return 0; } static int get_frame_info(struct mips_frame_info *info) { +#ifdef CONFIG_CPU_MICROMIPS + union mips_instruction *ip = (void *) (((char *) info->func) - 1); +#else union mips_instruction *ip = info->func; +#endif unsigned max_insns = info->func_size / sizeof(union mips_instruction); unsigned i; @@ -286,11 +342,30 @@ static int get_frame_info(struct mips_frame_info *info) for (i = 0; i < max_insns; i++, ip++) { - if (is_jal_jalr_jr_ins(ip)) + if (is_jump_ins(ip)) break; if (!info->frame_size) { if (is_sp_move_ins(ip)) + { +#ifdef CONFIG_CPU_MICROMIPS + if (mm_insn_16bit(ip->halfword[0])) + { + unsigned short tmp; + + if (ip->halfword[0] & mm_addiusp_func) + { + tmp = (((ip->halfword[0] >> 1) & 0x1ff) << 2); + info->frame_size = -(signed short)(tmp | ((tmp & 0x100) ? 0xfe00 : 0)); + } else { + tmp = (ip->halfword[0] >> 1); + info->frame_size = -(signed short)(tmp & 0xf); + } + ip = (void *) &ip->halfword[1]; + ip--; + } else +#endif info->frame_size = - ip->i_format.simmediate; + } continue; } if (info->pc_offset == -1 && is_ra_save_ins(ip)) { @@ -310,15 +385,42 @@ err: static struct mips_frame_info schedule_mfi __read_mostly; +#ifdef CONFIG_KALLSYMS +static unsigned long get___schedule_addr(void) +{ + return kallsyms_lookup_name("__schedule"); +} +#else +static unsigned long get___schedule_addr(void) +{ + union mips_instruction *ip = (void *)schedule; + int max_insns = 8; + int i; + + for (i = 0; i < max_insns; i++, ip++) { + if (ip->j_format.opcode == j_op) + return J_TARGET(ip, ip->j_format.target); + } + return 0; +} +#endif + static int __init frame_info_init(void) { unsigned long size = 0; #ifdef CONFIG_KALLSYMS unsigned long ofs; +#endif + unsigned long addr; + + addr = get___schedule_addr(); + if (!addr) + addr = (unsigned long)schedule; - kallsyms_lookup_size_offset((unsigned long)schedule, &size, &ofs); +#ifdef CONFIG_KALLSYMS + kallsyms_lookup_size_offset(addr, &size, &ofs); #endif - schedule_mfi.func = schedule; + schedule_mfi.func = (void *)addr; schedule_mfi.func_size = size; get_frame_info(&schedule_mfi); |