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/cacheflush.h> 22 23 void show_regs(struct pt_regs *regs) 24 { 25 show_regs_print_info(KERN_INFO); 26 27 pr_info(" Registers dump: mode=%X\r\n", regs->pt_mode); 28 pr_info(" r1=%08lX, r2=%08lX, r3=%08lX, r4=%08lX\n", 29 regs->r1, regs->r2, regs->r3, regs->r4); 30 pr_info(" r5=%08lX, r6=%08lX, r7=%08lX, r8=%08lX\n", 31 regs->r5, regs->r6, regs->r7, regs->r8); 32 pr_info(" r9=%08lX, r10=%08lX, r11=%08lX, r12=%08lX\n", 33 regs->r9, regs->r10, regs->r11, regs->r12); 34 pr_info(" r13=%08lX, r14=%08lX, r15=%08lX, r16=%08lX\n", 35 regs->r13, regs->r14, regs->r15, regs->r16); 36 pr_info(" r17=%08lX, r18=%08lX, r19=%08lX, r20=%08lX\n", 37 regs->r17, regs->r18, regs->r19, regs->r20); 38 pr_info(" r21=%08lX, r22=%08lX, r23=%08lX, r24=%08lX\n", 39 regs->r21, regs->r22, regs->r23, regs->r24); 40 pr_info(" r25=%08lX, r26=%08lX, r27=%08lX, r28=%08lX\n", 41 regs->r25, regs->r26, regs->r27, regs->r28); 42 pr_info(" r29=%08lX, r30=%08lX, r31=%08lX, rPC=%08lX\n", 43 regs->r29, regs->r30, regs->r31, regs->pc); 44 pr_info(" msr=%08lX, ear=%08lX, esr=%08lX, fsr=%08lX\n", 45 regs->msr, regs->ear, regs->esr, regs->fsr); 46 } 47 48 void (*pm_power_off)(void) = NULL; 49 EXPORT_SYMBOL(pm_power_off); 50 51 void flush_thread(void) 52 { 53 } 54 55 int copy_thread(struct task_struct *p, const struct kernel_clone_args *args) 56 { 57 unsigned long clone_flags = args->flags; 58 unsigned long usp = args->stack; 59 unsigned long tls = args->tls; 60 struct pt_regs *childregs = task_pt_regs(p); 61 struct thread_info *ti = task_thread_info(p); 62 63 if (unlikely(args->fn)) { 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)args->fn; 70 ti->cpu_context.r19 = (unsigned long)args->fn_arg; 71 childregs->pt_mode = 1; 72 local_save_flags(childregs->msr); 73 ti->cpu_context.msr = childregs->msr & ~MSR_IE; 74 ti->cpu_context.r15 = (unsigned long)ret_from_kernel_thread - 8; 75 return 0; 76 } 77 *childregs = *current_pt_regs(); 78 if (usp) 79 childregs->r1 = usp; 80 81 memset(&ti->cpu_context, 0, sizeof(struct cpu_context)); 82 ti->cpu_context.r1 = (unsigned long)childregs; 83 childregs->msr |= MSR_UMS; 84 85 /* we should consider the fact that childregs is a copy of the parent 86 * regs which were saved immediately after entering the kernel state 87 * before enabling VM. This MSR will be restored in switch_to and 88 * RETURN() and we want to have the right machine state there 89 * specifically this state must have INTs disabled before and enabled 90 * after performing rtbd 91 * compose the right MSR for RETURN(). It will work for switch_to also 92 * excepting for VM and UMS 93 * don't touch UMS , CARRY and cache bits 94 * right now MSR is a copy of parent one */ 95 childregs->msr &= ~MSR_EIP; 96 childregs->msr |= MSR_IE; 97 childregs->msr &= ~MSR_VM; 98 childregs->msr |= MSR_VMS; 99 childregs->msr |= MSR_EE; /* exceptions will be enabled*/ 100 101 ti->cpu_context.msr = (childregs->msr|MSR_VM); 102 ti->cpu_context.msr &= ~MSR_UMS; /* switch_to to kernel mode */ 103 ti->cpu_context.msr &= ~MSR_IE; 104 ti->cpu_context.r15 = (unsigned long)ret_from_fork - 8; 105 106 /* 107 * r21 is the thread reg, r10 is 6th arg to clone 108 * which contains TLS area 109 */ 110 if (clone_flags & CLONE_SETTLS) 111 childregs->r21 = tls; 112 113 return 0; 114 } 115 116 unsigned long __get_wchan(struct task_struct *p) 117 { 118 /* TBD (used by procfs) */ 119 return 0; 120 } 121 122 /* Set up a thread for executing a new program */ 123 void start_thread(struct pt_regs *regs, unsigned long pc, unsigned long usp) 124 { 125 regs->pc = pc; 126 regs->r1 = usp; 127 regs->pt_mode = 0; 128 regs->msr |= MSR_UMS; 129 regs->msr &= ~MSR_VM; 130 } 131 132 #include <linux/elfcore.h> 133 /* 134 * Set up a thread for executing a new program 135 */ 136 int elf_core_copy_task_fpregs(struct task_struct *t, elf_fpregset_t *fpu) 137 { 138 return 0; /* MicroBlaze has no separate FPU registers */ 139 } 140 141 void arch_cpu_idle(void) 142 { 143 } 144