1 /* 2 * Copyright (C) 2008-2009 Michal Simek <monstr@monstr.eu> 3 * Copyright (C) 2008-2009 PetaLogix 4 * Copyright (C) 2006 Atmark Techno, Inc. 5 * 6 * This file is subject to the terms and conditions of the GNU General Public 7 * License. See the file "COPYING" in the main directory of this archive 8 * for more details. 9 */ 10 11 #include <linux/cpu.h> 12 #include <linux/export.h> 13 #include <linux/sched.h> 14 #include <linux/sched/debug.h> 15 #include <linux/sched/task.h> 16 #include <linux/sched/task_stack.h> 17 #include <linux/pm.h> 18 #include <linux/tick.h> 19 #include <linux/bitops.h> 20 #include <linux/ptrace.h> 21 #include <asm/pgalloc.h> 22 #include <linux/uaccess.h> /* for USER_DS macros */ 23 #include <asm/cacheflush.h> 24 25 void show_regs(struct pt_regs *regs) 26 { 27 show_regs_print_info(KERN_INFO); 28 29 pr_info(" Registers dump: mode=%X\r\n", regs->pt_mode); 30 pr_info(" r1=%08lX, r2=%08lX, r3=%08lX, r4=%08lX\n", 31 regs->r1, regs->r2, regs->r3, regs->r4); 32 pr_info(" r5=%08lX, r6=%08lX, r7=%08lX, r8=%08lX\n", 33 regs->r5, regs->r6, regs->r7, regs->r8); 34 pr_info(" r9=%08lX, r10=%08lX, r11=%08lX, r12=%08lX\n", 35 regs->r9, regs->r10, regs->r11, regs->r12); 36 pr_info(" r13=%08lX, r14=%08lX, r15=%08lX, r16=%08lX\n", 37 regs->r13, regs->r14, regs->r15, regs->r16); 38 pr_info(" r17=%08lX, r18=%08lX, r19=%08lX, r20=%08lX\n", 39 regs->r17, regs->r18, regs->r19, regs->r20); 40 pr_info(" r21=%08lX, r22=%08lX, r23=%08lX, r24=%08lX\n", 41 regs->r21, regs->r22, regs->r23, regs->r24); 42 pr_info(" r25=%08lX, r26=%08lX, r27=%08lX, r28=%08lX\n", 43 regs->r25, regs->r26, regs->r27, regs->r28); 44 pr_info(" r29=%08lX, r30=%08lX, r31=%08lX, rPC=%08lX\n", 45 regs->r29, regs->r30, regs->r31, regs->pc); 46 pr_info(" msr=%08lX, ear=%08lX, esr=%08lX, fsr=%08lX\n", 47 regs->msr, regs->ear, regs->esr, regs->fsr); 48 } 49 50 void (*pm_power_off)(void) = NULL; 51 EXPORT_SYMBOL(pm_power_off); 52 53 void flush_thread(void) 54 { 55 } 56 57 int copy_thread(unsigned long clone_flags, unsigned long usp, 58 unsigned long arg, struct task_struct *p) 59 { 60 struct pt_regs *childregs = task_pt_regs(p); 61 struct thread_info *ti = task_thread_info(p); 62 63 if (unlikely(p->flags & PF_KTHREAD)) { 64 /* if we're creating a new kernel thread then just zeroing all 65 * the registers. That's OK for a brand new thread.*/ 66 memset(childregs, 0, sizeof(struct pt_regs)); 67 memset(&ti->cpu_context, 0, sizeof(struct cpu_context)); 68 ti->cpu_context.r1 = (unsigned long)childregs; 69 ti->cpu_context.r20 = (unsigned long)usp; /* fn */ 70 ti->cpu_context.r19 = (unsigned long)arg; 71 childregs->pt_mode = 1; 72 local_save_flags(childregs->msr); 73 #ifdef CONFIG_MMU 74 ti->cpu_context.msr = childregs->msr & ~MSR_IE; 75 #endif 76 ti->cpu_context.r15 = (unsigned long)ret_from_kernel_thread - 8; 77 return 0; 78 } 79 *childregs = *current_pt_regs(); 80 if (usp) 81 childregs->r1 = usp; 82 83 memset(&ti->cpu_context, 0, sizeof(struct cpu_context)); 84 ti->cpu_context.r1 = (unsigned long)childregs; 85 #ifndef CONFIG_MMU 86 ti->cpu_context.msr = (unsigned long)childregs->msr; 87 #else 88 childregs->msr |= MSR_UMS; 89 90 /* we should consider the fact that childregs is a copy of the parent 91 * regs which were saved immediately after entering the kernel state 92 * before enabling VM. This MSR will be restored in switch_to and 93 * RETURN() and we want to have the right machine state there 94 * specifically this state must have INTs disabled before and enabled 95 * after performing rtbd 96 * compose the right MSR for RETURN(). It will work for switch_to also 97 * excepting for VM and UMS 98 * don't touch UMS , CARRY and cache bits 99 * right now MSR is a copy of parent one */ 100 childregs->msr &= ~MSR_EIP; 101 childregs->msr |= MSR_IE; 102 childregs->msr &= ~MSR_VM; 103 childregs->msr |= MSR_VMS; 104 childregs->msr |= MSR_EE; /* exceptions will be enabled*/ 105 106 ti->cpu_context.msr = (childregs->msr|MSR_VM); 107 ti->cpu_context.msr &= ~MSR_UMS; /* switch_to to kernel mode */ 108 ti->cpu_context.msr &= ~MSR_IE; 109 #endif 110 ti->cpu_context.r15 = (unsigned long)ret_from_fork - 8; 111 112 /* 113 * r21 is the thread reg, r10 is 6th arg to clone 114 * which contains TLS area 115 */ 116 if (clone_flags & CLONE_SETTLS) 117 childregs->r21 = childregs->r10; 118 119 return 0; 120 } 121 122 unsigned long get_wchan(struct task_struct *p) 123 { 124 /* TBD (used by procfs) */ 125 return 0; 126 } 127 128 /* Set up a thread for executing a new program */ 129 void start_thread(struct pt_regs *regs, unsigned long pc, unsigned long usp) 130 { 131 regs->pc = pc; 132 regs->r1 = usp; 133 regs->pt_mode = 0; 134 #ifdef CONFIG_MMU 135 regs->msr |= MSR_UMS; 136 regs->msr &= ~MSR_VM; 137 #endif 138 } 139 140 #ifdef CONFIG_MMU 141 #include <linux/elfcore.h> 142 /* 143 * Set up a thread for executing a new program 144 */ 145 int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpregs) 146 { 147 return 0; /* MicroBlaze has no separate FPU registers */ 148 } 149 #endif /* CONFIG_MMU */ 150 151 void arch_cpu_idle(void) 152 { 153 local_irq_enable(); 154 } 155