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-rw-r--r--arch/sh/kernel/process_32.c465
1 files changed, 465 insertions, 0 deletions
diff --git a/arch/sh/kernel/process_32.c b/arch/sh/kernel/process_32.c
new file mode 100644
index 000000000000..9ab1926b9d10
--- /dev/null
+++ b/arch/sh/kernel/process_32.c
@@ -0,0 +1,465 @@
+/*
+ * arch/sh/kernel/process.c
+ *
+ * This file handles the architecture-dependent parts of process handling..
+ *
+ * Copyright (C) 1995 Linus Torvalds
+ *
+ * SuperH version: Copyright (C) 1999, 2000 Niibe Yutaka & Kaz Kojima
+ * Copyright (C) 2006 Lineo Solutions Inc. support SH4A UBC
+ * Copyright (C) 2002 - 2007 Paul Mundt
+ */
+#include <linux/module.h>
+#include <linux/mm.h>
+#include <linux/elfcore.h>
+#include <linux/pm.h>
+#include <linux/kallsyms.h>
+#include <linux/kexec.h>
+#include <linux/kdebug.h>
+#include <linux/tick.h>
+#include <linux/reboot.h>
+#include <linux/fs.h>
+#include <linux/preempt.h>
+#include <asm/uaccess.h>
+#include <asm/mmu_context.h>
+#include <asm/pgalloc.h>
+#include <asm/system.h>
+#include <asm/ubc.h>
+
+static int hlt_counter;
+int ubc_usercnt = 0;
+
+void (*pm_idle)(void);
+void (*pm_power_off)(void);
+EXPORT_SYMBOL(pm_power_off);
+
+void disable_hlt(void)
+{
+ hlt_counter++;
+}
+EXPORT_SYMBOL(disable_hlt);
+
+void enable_hlt(void)
+{
+ hlt_counter--;
+}
+EXPORT_SYMBOL(enable_hlt);
+
+static int __init nohlt_setup(char *__unused)
+{
+ hlt_counter = 1;
+ return 1;
+}
+__setup("nohlt", nohlt_setup);
+
+static int __init hlt_setup(char *__unused)
+{
+ hlt_counter = 0;
+ return 1;
+}
+__setup("hlt", hlt_setup);
+
+void default_idle(void)
+{
+ if (!hlt_counter) {
+ clear_thread_flag(TIF_POLLING_NRFLAG);
+ smp_mb__after_clear_bit();
+ set_bl_bit();
+ while (!need_resched())
+ cpu_sleep();
+ clear_bl_bit();
+ set_thread_flag(TIF_POLLING_NRFLAG);
+ } else
+ while (!need_resched())
+ cpu_relax();
+}
+
+void cpu_idle(void)
+{
+ set_thread_flag(TIF_POLLING_NRFLAG);
+
+ /* endless idle loop with no priority at all */
+ while (1) {
+ void (*idle)(void) = pm_idle;
+
+ if (!idle)
+ idle = default_idle;
+
+ tick_nohz_stop_sched_tick();
+ while (!need_resched())
+ idle();
+ tick_nohz_restart_sched_tick();
+
+ preempt_enable_no_resched();
+ schedule();
+ preempt_disable();
+ check_pgt_cache();
+ }
+}
+
+void machine_restart(char * __unused)
+{
+ /* SR.BL=1 and invoke address error to let CPU reset (manual reset) */
+ asm volatile("ldc %0, sr\n\t"
+ "mov.l @%1, %0" : : "r" (0x10000000), "r" (0x80000001));
+}
+
+void machine_halt(void)
+{
+ local_irq_disable();
+
+ while (1)
+ cpu_sleep();
+}
+
+void machine_power_off(void)
+{
+ if (pm_power_off)
+ pm_power_off();
+}
+
+void show_regs(struct pt_regs * regs)
+{
+ printk("\n");
+ printk("Pid : %d, Comm: %20s\n", task_pid_nr(current), current->comm);
+ print_symbol("PC is at %s\n", instruction_pointer(regs));
+ printk("PC : %08lx SP : %08lx SR : %08lx ",
+ regs->pc, regs->regs[15], regs->sr);
+#ifdef CONFIG_MMU
+ printk("TEA : %08x ", ctrl_inl(MMU_TEA));
+#else
+ printk(" ");
+#endif
+ printk("%s\n", print_tainted());
+
+ printk("R0 : %08lx R1 : %08lx R2 : %08lx R3 : %08lx\n",
+ regs->regs[0],regs->regs[1],
+ regs->regs[2],regs->regs[3]);
+ printk("R4 : %08lx R5 : %08lx R6 : %08lx R7 : %08lx\n",
+ regs->regs[4],regs->regs[5],
+ regs->regs[6],regs->regs[7]);
+ printk("R8 : %08lx R9 : %08lx R10 : %08lx R11 : %08lx\n",
+ regs->regs[8],regs->regs[9],
+ regs->regs[10],regs->regs[11]);
+ printk("R12 : %08lx R13 : %08lx R14 : %08lx\n",
+ regs->regs[12],regs->regs[13],
+ regs->regs[14]);
+ printk("MACH: %08lx MACL: %08lx GBR : %08lx PR : %08lx\n",
+ regs->mach, regs->macl, regs->gbr, regs->pr);
+
+ show_trace(NULL, (unsigned long *)regs->regs[15], regs);
+}
+
+/*
+ * Create a kernel thread
+ */
+
+/*
+ * This is the mechanism for creating a new kernel thread.
+ *
+ */
+extern void kernel_thread_helper(void);
+__asm__(".align 5\n"
+ "kernel_thread_helper:\n\t"
+ "jsr @r5\n\t"
+ " nop\n\t"
+ "mov.l 1f, r1\n\t"
+ "jsr @r1\n\t"
+ " mov r0, r4\n\t"
+ ".align 2\n\t"
+ "1:.long do_exit");
+
+/* Don't use this in BL=1(cli). Or else, CPU resets! */
+int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
+{
+ struct pt_regs regs;
+
+ memset(&regs, 0, sizeof(regs));
+ regs.regs[4] = (unsigned long)arg;
+ regs.regs[5] = (unsigned long)fn;
+
+ regs.pc = (unsigned long)kernel_thread_helper;
+ regs.sr = (1 << 30);
+
+ /* Ok, create the new process.. */
+ return do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0,
+ &regs, 0, NULL, NULL);
+}
+
+/*
+ * Free current thread data structures etc..
+ */
+void exit_thread(void)
+{
+ if (current->thread.ubc_pc) {
+ current->thread.ubc_pc = 0;
+ ubc_usercnt -= 1;
+ }
+}
+
+void flush_thread(void)
+{
+#if defined(CONFIG_SH_FPU)
+ struct task_struct *tsk = current;
+ /* Forget lazy FPU state */
+ clear_fpu(tsk, task_pt_regs(tsk));
+ clear_used_math();
+#endif
+}
+
+void release_thread(struct task_struct *dead_task)
+{
+ /* do nothing */
+}
+
+/* Fill in the fpu structure for a core dump.. */
+int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpu)
+{
+ int fpvalid = 0;
+
+#if defined(CONFIG_SH_FPU)
+ struct task_struct *tsk = current;
+
+ fpvalid = !!tsk_used_math(tsk);
+ if (fpvalid) {
+ unlazy_fpu(tsk, regs);
+ memcpy(fpu, &tsk->thread.fpu.hard, sizeof(*fpu));
+ }
+#endif
+
+ return fpvalid;
+}
+
+asmlinkage void ret_from_fork(void);
+
+int copy_thread(int nr, unsigned long clone_flags, unsigned long usp,
+ unsigned long unused,
+ struct task_struct *p, struct pt_regs *regs)
+{
+ struct thread_info *ti = task_thread_info(p);
+ struct pt_regs *childregs;
+#if defined(CONFIG_SH_FPU)
+ struct task_struct *tsk = current;
+
+ unlazy_fpu(tsk, regs);
+ p->thread.fpu = tsk->thread.fpu;
+ copy_to_stopped_child_used_math(p);
+#endif
+
+ childregs = task_pt_regs(p);
+ *childregs = *regs;
+
+ if (user_mode(regs)) {
+ childregs->regs[15] = usp;
+ ti->addr_limit = USER_DS;
+ } else {
+ childregs->regs[15] = (unsigned long)childregs;
+ ti->addr_limit = KERNEL_DS;
+ }
+
+ if (clone_flags & CLONE_SETTLS)
+ childregs->gbr = childregs->regs[0];
+
+ childregs->regs[0] = 0; /* Set return value for child */
+
+ p->thread.sp = (unsigned long) childregs;
+ p->thread.pc = (unsigned long) ret_from_fork;
+
+ p->thread.ubc_pc = 0;
+
+ return 0;
+}
+
+/* Tracing by user break controller. */
+static void ubc_set_tracing(int asid, unsigned long pc)
+{
+#if defined(CONFIG_CPU_SH4A)
+ unsigned long val;
+
+ val = (UBC_CBR_ID_INST | UBC_CBR_RW_READ | UBC_CBR_CE);
+ val |= (UBC_CBR_AIE | UBC_CBR_AIV_SET(asid));
+
+ ctrl_outl(val, UBC_CBR0);
+ ctrl_outl(pc, UBC_CAR0);
+ ctrl_outl(0x0, UBC_CAMR0);
+ ctrl_outl(0x0, UBC_CBCR);
+
+ val = (UBC_CRR_RES | UBC_CRR_PCB | UBC_CRR_BIE);
+ ctrl_outl(val, UBC_CRR0);
+
+ /* Read UBC register that we wrote last, for checking update */
+ val = ctrl_inl(UBC_CRR0);
+
+#else /* CONFIG_CPU_SH4A */
+ ctrl_outl(pc, UBC_BARA);
+
+#ifdef CONFIG_MMU
+ ctrl_outb(asid, UBC_BASRA);
+#endif
+
+ ctrl_outl(0, UBC_BAMRA);
+
+ if (current_cpu_data.type == CPU_SH7729 ||
+ current_cpu_data.type == CPU_SH7710 ||
+ current_cpu_data.type == CPU_SH7712) {
+ ctrl_outw(BBR_INST | BBR_READ | BBR_CPU, UBC_BBRA);
+ ctrl_outl(BRCR_PCBA | BRCR_PCTE, UBC_BRCR);
+ } else {
+ ctrl_outw(BBR_INST | BBR_READ, UBC_BBRA);
+ ctrl_outw(BRCR_PCBA, UBC_BRCR);
+ }
+#endif /* CONFIG_CPU_SH4A */
+}
+
+/*
+ * switch_to(x,y) should switch tasks from x to y.
+ *
+ */
+struct task_struct *__switch_to(struct task_struct *prev,
+ struct task_struct *next)
+{
+#if defined(CONFIG_SH_FPU)
+ unlazy_fpu(prev, task_pt_regs(prev));
+#endif
+
+#ifdef CONFIG_MMU
+ /*
+ * Restore the kernel mode register
+ * k7 (r7_bank1)
+ */
+ asm volatile("ldc %0, r7_bank"
+ : /* no output */
+ : "r" (task_thread_info(next)));
+#endif
+
+ /* If no tasks are using the UBC, we're done */
+ if (ubc_usercnt == 0)
+ /* If no tasks are using the UBC, we're done */;
+ else if (next->thread.ubc_pc && next->mm) {
+ int asid = 0;
+#ifdef CONFIG_MMU
+ asid |= cpu_asid(smp_processor_id(), next->mm);
+#endif
+ ubc_set_tracing(asid, next->thread.ubc_pc);
+ } else {
+#if defined(CONFIG_CPU_SH4A)
+ ctrl_outl(UBC_CBR_INIT, UBC_CBR0);
+ ctrl_outl(UBC_CRR_INIT, UBC_CRR0);
+#else
+ ctrl_outw(0, UBC_BBRA);
+ ctrl_outw(0, UBC_BBRB);
+#endif
+ }
+
+ return prev;
+}
+
+asmlinkage int sys_fork(unsigned long r4, unsigned long r5,
+ unsigned long r6, unsigned long r7,
+ struct pt_regs __regs)
+{
+#ifdef CONFIG_MMU
+ struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
+ return do_fork(SIGCHLD, regs->regs[15], regs, 0, NULL, NULL);
+#else
+ /* fork almost works, enough to trick you into looking elsewhere :-( */
+ return -EINVAL;
+#endif
+}
+
+asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp,
+ unsigned long parent_tidptr,
+ unsigned long child_tidptr,
+ struct pt_regs __regs)
+{
+ struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
+ if (!newsp)
+ newsp = regs->regs[15];
+ return do_fork(clone_flags, newsp, regs, 0,
+ (int __user *)parent_tidptr,
+ (int __user *)child_tidptr);
+}
+
+/*
+ * This is trivial, and on the face of it looks like it
+ * could equally well be done in user mode.
+ *
+ * Not so, for quite unobvious reasons - register pressure.
+ * In user mode vfork() cannot have a stack frame, and if
+ * done by calling the "clone()" system call directly, you
+ * do not have enough call-clobbered registers to hold all
+ * the information you need.
+ */
+asmlinkage int sys_vfork(unsigned long r4, unsigned long r5,
+ unsigned long r6, unsigned long r7,
+ struct pt_regs __regs)
+{
+ struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
+ return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->regs[15], regs,
+ 0, NULL, NULL);
+}
+
+/*
+ * sys_execve() executes a new program.
+ */
+asmlinkage int sys_execve(char __user *ufilename, char __user * __user *uargv,
+ char __user * __user *uenvp, unsigned long r7,
+ struct pt_regs __regs)
+{
+ struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
+ int error;
+ char *filename;
+
+ filename = getname(ufilename);
+ error = PTR_ERR(filename);
+ if (IS_ERR(filename))
+ goto out;
+
+ error = do_execve(filename, uargv, uenvp, regs);
+ if (error == 0) {
+ task_lock(current);
+ current->ptrace &= ~PT_DTRACE;
+ task_unlock(current);
+ }
+ putname(filename);
+out:
+ return error;
+}
+
+unsigned long get_wchan(struct task_struct *p)
+{
+ unsigned long pc;
+
+ if (!p || p == current || p->state == TASK_RUNNING)
+ return 0;
+
+ /*
+ * The same comment as on the Alpha applies here, too ...
+ */
+ pc = thread_saved_pc(p);
+
+#ifdef CONFIG_FRAME_POINTER
+ if (in_sched_functions(pc)) {
+ unsigned long schedule_frame = (unsigned long)p->thread.sp;
+ return ((unsigned long *)schedule_frame)[21];
+ }
+#endif
+
+ return pc;
+}
+
+asmlinkage void break_point_trap(void)
+{
+ /* Clear tracing. */
+#if defined(CONFIG_CPU_SH4A)
+ ctrl_outl(UBC_CBR_INIT, UBC_CBR0);
+ ctrl_outl(UBC_CRR_INIT, UBC_CRR0);
+#else
+ ctrl_outw(0, UBC_BBRA);
+ ctrl_outw(0, UBC_BBRB);
+#endif
+ current->thread.ubc_pc = 0;
+ ubc_usercnt -= 1;
+
+ force_sig(SIGTRAP, current);
+}
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