sh: Split out arch/sh/kernel/process.c for _32 and _64 variants.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

1 files changed, 558 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..6d7f2b07e491
--- /dev/null
+++ b/arch/sh/kernel/process_32.c
@@ -0,0 +1,558 @@
+/*
+ * 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;
+}
+
+/*
+ * Capture the user space registers if the task is not running (in user space)
+ */
+int dump_task_regs(struct task_struct *tsk, elf_gregset_t *regs)
+{
+	struct pt_regs ptregs;
+
+	ptregs = *task_pt_regs(tsk);
+	elf_core_copy_regs(regs, &ptregs);
+
+	return 1;
+}
+
+int dump_task_fpu(struct task_struct *tsk, elf_fpregset_t *fpu)
+{
+	int fpvalid = 0;
+
+#if defined(CONFIG_SH_FPU)
+	fpvalid = !!tsk_used_math(tsk);
+	if (fpvalid) {
+		unlazy_fpu(tsk, task_pt_regs(tsk));
+		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
+
+#if defined(CONFIG_GUSA) && defined(CONFIG_PREEMPT)
+	{
+		struct pt_regs *regs;
+
+		preempt_disable();
+		regs = task_pt_regs(prev);
+		if (user_mode(regs) && regs->regs[15] >= 0xc0000000) {
+			int offset = (int)regs->regs[15];
+
+			/* Reset stack pointer: clear critical region mark */
+			regs->regs[15] = regs->regs[1];
+			if (regs->pc < regs->regs[0])
+				/* Go to rewind point */
+				regs->pc = regs->regs[0] + offset;
+		}
+		preempt_enable_no_resched();
+	}
+#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);
+}
+
+/*
+ * Generic trap handler.
+ */
+asmlinkage void debug_trap_handler(unsigned long r4, unsigned long r5,
+				   unsigned long r6, unsigned long r7,
+				   struct pt_regs __regs)
+{
+	struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
+
+	/* Rewind */
+	regs->pc -= instruction_size(ctrl_inw(regs->pc - 4));
+
+	if (notify_die(DIE_TRAP, "debug trap", regs, 0, regs->tra & 0xff,
+		       SIGTRAP) == NOTIFY_STOP)
+		return;
+
+	force_sig(SIGTRAP, current);
+}
+
+/*
+ * Special handler for BUG() traps.
+ */
+asmlinkage void bug_trap_handler(unsigned long r4, unsigned long r5,
+				 unsigned long r6, unsigned long r7,
+				 struct pt_regs __regs)
+{
+	struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
+
+	/* Rewind */
+	regs->pc -= instruction_size(ctrl_inw(regs->pc - 4));
+
+	if (notify_die(DIE_TRAP, "bug trap", regs, 0, TRAPA_BUG_OPCODE & 0xff,
+		       SIGTRAP) == NOTIFY_STOP)
+		return;
+
+#ifdef CONFIG_BUG
+	if (__kernel_text_address(instruction_pointer(regs))) {
+		u16 insn = *(u16 *)instruction_pointer(regs);
+		if (insn == TRAPA_BUG_OPCODE)
+			handle_BUG(regs);
+	}
+#endif
+
+	force_sig(SIGTRAP, current);
+}