2 * arch/sh/kernel/process.c
4 * This file handles the architecture-dependent parts of process handling..
6 * Copyright (C) 1995 Linus Torvalds
8 * SuperH version: Copyright (C) 1999, 2000 Niibe Yutaka & Kaz Kojima
9 * Copyright (C) 2006 Lineo Solutions Inc. support SH4A UBC
10 * Copyright (C) 2002 - 2008 Paul Mundt
12 * This file is subject to the terms and conditions of the GNU General Public
13 * License. See the file "COPYING" in the main directory of this archive
16 #include <linux/module.h>
18 #include <linux/elfcore.h>
20 #include <linux/kallsyms.h>
21 #include <linux/kexec.h>
22 #include <linux/kdebug.h>
23 #include <linux/tick.h>
24 #include <linux/reboot.h>
26 #include <linux/preempt.h>
27 #include <asm/uaccess.h>
28 #include <asm/mmu_context.h>
29 #include <asm/pgalloc.h>
30 #include <asm/system.h>
33 #include <asm/syscalls.h>
37 void machine_restart(char * __unused
)
39 /* SR.BL=1 and invoke address error to let CPU reset (manual reset) */
40 asm volatile("ldc %0, sr\n\t"
41 "mov.l @%1, %0" : : "r" (0x10000000), "r" (0x80000001));
44 void machine_halt(void)
52 void machine_power_off(void)
58 void show_regs(struct pt_regs
* regs
)
61 printk("Pid : %d, Comm: \t\t%s\n", task_pid_nr(current
), current
->comm
);
62 printk("CPU : %d \t\t%s (%s %.*s)\n\n",
63 smp_processor_id(), print_tainted(), init_utsname()->release
,
64 (int)strcspn(init_utsname()->version
, " "),
65 init_utsname()->version
);
67 print_symbol("PC is at %s\n", instruction_pointer(regs
));
68 print_symbol("PR is at %s\n", regs
->pr
);
70 printk("PC : %08lx SP : %08lx SR : %08lx ",
71 regs
->pc
, regs
->regs
[15], regs
->sr
);
73 printk("TEA : %08x\n", ctrl_inl(MMU_TEA
));
78 printk("R0 : %08lx R1 : %08lx R2 : %08lx R3 : %08lx\n",
79 regs
->regs
[0],regs
->regs
[1],
80 regs
->regs
[2],regs
->regs
[3]);
81 printk("R4 : %08lx R5 : %08lx R6 : %08lx R7 : %08lx\n",
82 regs
->regs
[4],regs
->regs
[5],
83 regs
->regs
[6],regs
->regs
[7]);
84 printk("R8 : %08lx R9 : %08lx R10 : %08lx R11 : %08lx\n",
85 regs
->regs
[8],regs
->regs
[9],
86 regs
->regs
[10],regs
->regs
[11]);
87 printk("R12 : %08lx R13 : %08lx R14 : %08lx\n",
88 regs
->regs
[12],regs
->regs
[13],
90 printk("MACH: %08lx MACL: %08lx GBR : %08lx PR : %08lx\n",
91 regs
->mach
, regs
->macl
, regs
->gbr
, regs
->pr
);
93 show_trace(NULL
, (unsigned long *)regs
->regs
[15], regs
);
98 * Create a kernel thread
100 ATTRIB_NORET
void kernel_thread_helper(void *arg
, int (*fn
)(void *))
105 /* Don't use this in BL=1(cli). Or else, CPU resets! */
106 int kernel_thread(int (*fn
)(void *), void * arg
, unsigned long flags
)
111 memset(®s
, 0, sizeof(regs
));
112 regs
.regs
[4] = (unsigned long)arg
;
113 regs
.regs
[5] = (unsigned long)fn
;
115 regs
.pc
= (unsigned long)kernel_thread_helper
;
118 /* Ok, create the new process.. */
119 pid
= do_fork(flags
| CLONE_VM
| CLONE_UNTRACED
, 0,
120 ®s
, 0, NULL
, NULL
);
122 trace_mark(kernel_arch_kthread_create
, "pid %d fn %p", pid
, fn
);
128 * Free current thread data structures etc..
130 void exit_thread(void)
132 if (current
->thread
.ubc_pc
) {
133 current
->thread
.ubc_pc
= 0;
138 void flush_thread(void)
140 #if defined(CONFIG_SH_FPU)
141 struct task_struct
*tsk
= current
;
142 /* Forget lazy FPU state */
143 clear_fpu(tsk
, task_pt_regs(tsk
));
148 void release_thread(struct task_struct
*dead_task
)
153 /* Fill in the fpu structure for a core dump.. */
154 int dump_fpu(struct pt_regs
*regs
, elf_fpregset_t
*fpu
)
158 #if defined(CONFIG_SH_FPU)
159 struct task_struct
*tsk
= current
;
161 fpvalid
= !!tsk_used_math(tsk
);
163 fpvalid
= !fpregs_get(tsk
, NULL
, 0,
164 sizeof(struct user_fpu_struct
),
171 asmlinkage
void ret_from_fork(void);
173 int copy_thread(int nr
, unsigned long clone_flags
, unsigned long usp
,
174 unsigned long unused
,
175 struct task_struct
*p
, struct pt_regs
*regs
)
177 struct thread_info
*ti
= task_thread_info(p
);
178 struct pt_regs
*childregs
;
179 #if defined(CONFIG_SH_FPU)
180 struct task_struct
*tsk
= current
;
182 unlazy_fpu(tsk
, regs
);
183 p
->thread
.fpu
= tsk
->thread
.fpu
;
184 copy_to_stopped_child_used_math(p
);
187 childregs
= task_pt_regs(p
);
190 if (user_mode(regs
)) {
191 childregs
->regs
[15] = usp
;
192 ti
->addr_limit
= USER_DS
;
194 childregs
->regs
[15] = (unsigned long)childregs
;
195 ti
->addr_limit
= KERNEL_DS
;
198 if (clone_flags
& CLONE_SETTLS
)
199 childregs
->gbr
= childregs
->regs
[0];
201 childregs
->regs
[0] = 0; /* Set return value for child */
203 p
->thread
.sp
= (unsigned long) childregs
;
204 p
->thread
.pc
= (unsigned long) ret_from_fork
;
206 p
->thread
.ubc_pc
= 0;
211 /* Tracing by user break controller. */
212 static void ubc_set_tracing(int asid
, unsigned long pc
)
214 #if defined(CONFIG_CPU_SH4A)
217 val
= (UBC_CBR_ID_INST
| UBC_CBR_RW_READ
| UBC_CBR_CE
);
218 val
|= (UBC_CBR_AIE
| UBC_CBR_AIV_SET(asid
));
220 ctrl_outl(val
, UBC_CBR0
);
221 ctrl_outl(pc
, UBC_CAR0
);
222 ctrl_outl(0x0, UBC_CAMR0
);
223 ctrl_outl(0x0, UBC_CBCR
);
225 val
= (UBC_CRR_RES
| UBC_CRR_PCB
| UBC_CRR_BIE
);
226 ctrl_outl(val
, UBC_CRR0
);
228 /* Read UBC register that we wrote last, for checking update */
229 val
= ctrl_inl(UBC_CRR0
);
231 #else /* CONFIG_CPU_SH4A */
232 ctrl_outl(pc
, UBC_BARA
);
235 ctrl_outb(asid
, UBC_BASRA
);
238 ctrl_outl(0, UBC_BAMRA
);
240 if (current_cpu_data
.type
== CPU_SH7729
||
241 current_cpu_data
.type
== CPU_SH7710
||
242 current_cpu_data
.type
== CPU_SH7712
) {
243 ctrl_outw(BBR_INST
| BBR_READ
| BBR_CPU
, UBC_BBRA
);
244 ctrl_outl(BRCR_PCBA
| BRCR_PCTE
, UBC_BRCR
);
246 ctrl_outw(BBR_INST
| BBR_READ
, UBC_BBRA
);
247 ctrl_outw(BRCR_PCBA
, UBC_BRCR
);
249 #endif /* CONFIG_CPU_SH4A */
253 * switch_to(x,y) should switch tasks from x to y.
256 struct task_struct
*__switch_to(struct task_struct
*prev
,
257 struct task_struct
*next
)
259 #if defined(CONFIG_SH_FPU)
260 unlazy_fpu(prev
, task_pt_regs(prev
));
265 * Restore the kernel mode register
268 asm volatile("ldc %0, r7_bank"
270 : "r" (task_thread_info(next
)));
273 /* If no tasks are using the UBC, we're done */
274 if (ubc_usercnt
== 0)
275 /* If no tasks are using the UBC, we're done */;
276 else if (next
->thread
.ubc_pc
&& next
->mm
) {
279 asid
|= cpu_asid(smp_processor_id(), next
->mm
);
281 ubc_set_tracing(asid
, next
->thread
.ubc_pc
);
283 #if defined(CONFIG_CPU_SH4A)
284 ctrl_outl(UBC_CBR_INIT
, UBC_CBR0
);
285 ctrl_outl(UBC_CRR_INIT
, UBC_CRR0
);
287 ctrl_outw(0, UBC_BBRA
);
288 ctrl_outw(0, UBC_BBRB
);
295 asmlinkage
int sys_fork(unsigned long r4
, unsigned long r5
,
296 unsigned long r6
, unsigned long r7
,
297 struct pt_regs __regs
)
300 struct pt_regs
*regs
= RELOC_HIDE(&__regs
, 0);
301 return do_fork(SIGCHLD
, regs
->regs
[15], regs
, 0, NULL
, NULL
);
303 /* fork almost works, enough to trick you into looking elsewhere :-( */
308 asmlinkage
int sys_clone(unsigned long clone_flags
, unsigned long newsp
,
309 unsigned long parent_tidptr
,
310 unsigned long child_tidptr
,
311 struct pt_regs __regs
)
313 struct pt_regs
*regs
= RELOC_HIDE(&__regs
, 0);
315 newsp
= regs
->regs
[15];
316 return do_fork(clone_flags
, newsp
, regs
, 0,
317 (int __user
*)parent_tidptr
,
318 (int __user
*)child_tidptr
);
322 * This is trivial, and on the face of it looks like it
323 * could equally well be done in user mode.
325 * Not so, for quite unobvious reasons - register pressure.
326 * In user mode vfork() cannot have a stack frame, and if
327 * done by calling the "clone()" system call directly, you
328 * do not have enough call-clobbered registers to hold all
329 * the information you need.
331 asmlinkage
int sys_vfork(unsigned long r4
, unsigned long r5
,
332 unsigned long r6
, unsigned long r7
,
333 struct pt_regs __regs
)
335 struct pt_regs
*regs
= RELOC_HIDE(&__regs
, 0);
336 return do_fork(CLONE_VFORK
| CLONE_VM
| SIGCHLD
, regs
->regs
[15], regs
,
341 * sys_execve() executes a new program.
343 asmlinkage
int sys_execve(char __user
*ufilename
, char __user
* __user
*uargv
,
344 char __user
* __user
*uenvp
, unsigned long r7
,
345 struct pt_regs __regs
)
347 struct pt_regs
*regs
= RELOC_HIDE(&__regs
, 0);
351 filename
= getname(ufilename
);
352 error
= PTR_ERR(filename
);
353 if (IS_ERR(filename
))
356 error
= do_execve(filename
, uargv
, uenvp
, regs
);
359 current
->ptrace
&= ~PT_DTRACE
;
360 task_unlock(current
);
367 unsigned long get_wchan(struct task_struct
*p
)
371 if (!p
|| p
== current
|| p
->state
== TASK_RUNNING
)
375 * The same comment as on the Alpha applies here, too ...
377 pc
= thread_saved_pc(p
);
379 #ifdef CONFIG_FRAME_POINTER
380 if (in_sched_functions(pc
)) {
381 unsigned long schedule_frame
= (unsigned long)p
->thread
.sp
;
382 return ((unsigned long *)schedule_frame
)[21];
389 asmlinkage
void break_point_trap(void)
392 #if defined(CONFIG_CPU_SH4A)
393 ctrl_outl(UBC_CBR_INIT
, UBC_CBR0
);
394 ctrl_outl(UBC_CRR_INIT
, UBC_CRR0
);
396 ctrl_outw(0, UBC_BBRA
);
397 ctrl_outw(0, UBC_BBRB
);
399 current
->thread
.ubc_pc
= 0;
402 force_sig(SIGTRAP
, current
);