2 * Copyright (C) 2000-2003 Axis Communications AB
4 * Authors: Bjorn Wesen (bjornw@axis.com)
5 * Mikael Starvik (starvik@axis.com)
6 * Tobias Anderberg (tobiasa@axis.com), CRISv32 port.
8 * This file handles the architecture-dependent parts of process handling..
11 #include <linux/sched.h>
12 #include <linux/sched/debug.h>
13 #include <linux/sched/task.h>
14 #include <linux/sched/task_stack.h>
15 #include <linux/slab.h>
16 #include <linux/err.h>
18 #include <hwregs/reg_rdwr.h>
19 #include <hwregs/reg_map.h>
20 #include <hwregs/timer_defs.h>
21 #include <hwregs/intr_vect_defs.h>
22 #include <linux/ptrace.h>
24 extern void stop_watchdog(void);
26 /* We use this if we don't have any better idle routine. */
27 void default_idle(void)
30 /* Halt until exception. */
31 __asm__
volatile("halt");
35 * Free current thread data structures etc..
38 extern void deconfigure_bp(long pid
);
39 void exit_thread(struct task_struct
*tsk
)
41 deconfigure_bp(tsk
->pid
);
45 * If the watchdog is enabled, disable interrupts and enter an infinite loop.
46 * The watchdog will reset the CPU after 0.1s. If the watchdog isn't enabled
47 * then enable it and wait.
49 extern void arch_enable_nmi(void);
55 * Don't declare this variable elsewhere. We don't want any other
56 * code to know about it than the watchdog handler in entry.S and
57 * this code, implementing hard reset through the watchdog.
59 #if defined(CONFIG_ETRAX_WATCHDOG)
60 extern int cause_of_death
;
63 printk("*** HARD RESET ***\n");
66 #if defined(CONFIG_ETRAX_WATCHDOG)
67 cause_of_death
= 0xbedead;
70 reg_timer_rw_wd_ctrl wd_ctrl
= {0};
74 wd_ctrl
.key
= 16; /* Arbitrary key. */
75 wd_ctrl
.cnt
= 1; /* Minimum time. */
76 wd_ctrl
.cmd
= regk_timer_start
;
79 REG_WR(timer
, regi_timer0
, rw_wd_ctrl
, wd_ctrl
);
84 ; /* Wait for reset. */
88 * Return saved PC of a blocked thread.
90 unsigned long thread_saved_pc(struct task_struct
*t
)
92 return task_pt_regs(t
)->erp
;
96 * Setup the child's kernel stack with a pt_regs and call switch_stack() on it.
97 * It will be unnested during _resume and _ret_from_sys_call when the new thread
100 * Also setup the thread switching structure which is used to keep
101 * thread-specific data during _resumes.
104 extern asmlinkage
void ret_from_fork(void);
105 extern asmlinkage
void ret_from_kernel_thread(void);
108 copy_thread(unsigned long clone_flags
, unsigned long usp
,
109 unsigned long arg
, struct task_struct
*p
)
111 struct pt_regs
*childregs
= task_pt_regs(p
);
112 struct switch_stack
*swstack
= ((struct switch_stack
*) childregs
) - 1;
115 * Put the pt_regs structure at the end of the new kernel stack page and
116 * fix it up. Note: the task_struct doubles as the kernel stack for the
119 if (unlikely(p
->flags
& PF_KTHREAD
)) {
121 sizeof(struct switch_stack
) + sizeof(struct pt_regs
));
124 childregs
->ccs
= 1 << (I_CCS_BITNR
+ CCS_SHIFT
);
125 swstack
->return_ip
= (unsigned long) ret_from_kernel_thread
;
126 p
->thread
.ksp
= (unsigned long) swstack
;
130 *childregs
= *current_pt_regs(); /* Struct copy of pt_regs. */
131 childregs
->r10
= 0; /* Child returns 0 after a fork/clone. */
134 * The TLS is in $mof because it is the 5th argument to sys_clone.
136 if (p
->mm
&& (clone_flags
& CLONE_SETTLS
)) {
137 task_thread_info(p
)->tls
= childregs
->mof
;
140 /* Put the switch stack right below the pt_regs. */
142 /* Parameter to ret_from_sys_call. 0 is don't restart the syscall. */
146 * We want to return into ret_from_sys_call after the _resume.
147 * ret_from_fork will call ret_from_sys_call.
149 swstack
->return_ip
= (unsigned long) ret_from_fork
;
151 /* Fix the user-mode and kernel-mode stackpointer. */
152 p
->thread
.usp
= usp
?: rdusp();
153 p
->thread
.ksp
= (unsigned long) swstack
;
159 get_wchan(struct task_struct
*p
)
167 void show_regs(struct pt_regs
* regs
)
169 unsigned long usp
= rdusp();
171 show_regs_print_info(KERN_DEFAULT
);
173 printk("ERP: %08lx SRP: %08lx CCS: %08lx USP: %08lx MOF: %08lx\n",
174 regs
->erp
, regs
->srp
, regs
->ccs
, usp
, regs
->mof
);
176 printk(" r0: %08lx r1: %08lx r2: %08lx r3: %08lx\n",
177 regs
->r0
, regs
->r1
, regs
->r2
, regs
->r3
);
179 printk(" r4: %08lx r5: %08lx r6: %08lx r7: %08lx\n",
180 regs
->r4
, regs
->r5
, regs
->r6
, regs
->r7
);
182 printk(" r8: %08lx r9: %08lx r10: %08lx r11: %08lx\n",
183 regs
->r8
, regs
->r9
, regs
->r10
, regs
->r11
);
185 printk("r12: %08lx r13: %08lx oR10: %08lx\n",
186 regs
->r12
, regs
->r13
, regs
->orig_r10
);