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
23void 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
48void (*pm_power_off)(void) = NULL;
49EXPORT_SYMBOL(pm_power_off);
50
51void flush_thread(void)
52{
53}
54
55int 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
116unsigned 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 */
123void 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 */
136int 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
141void arch_cpu_idle(void)
142{
143}
144