h8300: Interrupt and exceptions

/*

 * linux/arch/h8300/kernel/irq.c

 *

 * Copyright 2014-2015 Yoshinori Sato <ysato@users.sourceforge.jp>

 */

#include <linux/init.h>

#include <linux/interrupt.h>

#include <linux/irq.h>

#include <linux/irqdomain.h>

#include <linux/of_irq.h>

#include <asm/traps.h>

#ifdef CONFIG_RAMKERNEL

typedef void (*h8300_vector)(void);

static const h8300_vector __initconst trap_table[] = {

	0, 0, 0, 0,

	_trace_break,

	0, 0,

	_nmi,

	_system_call,

	0, 0,

	_trace_break,

};

static unsigned long __init *get_vector_address(void)

{

	unsigned long *rom_vector = CPU_VECTOR;

	unsigned long base, tmp;

	int vec_no;

	base = rom_vector[EXT_IRQ0] & ADDR_MASK;

	/* check romvector format */

	for (vec_no = EXT_IRQ0 + 1; vec_no <= EXT_IRQ0+EXT_IRQS; vec_no++) {

		if ((base+(vec_no - EXT_IRQ0)*4) !=

		    (rom_vector[vec_no] & ADDR_MASK))

			return NULL;

	}

	/* ramvector base address */

	base -= EXT_IRQ0*4;

	/* writerble? */

	tmp = ~(*(volatile unsigned long *)base);

	(*(volatile unsigned long *)base) = tmp;

	if ((*(volatile unsigned long *)base) != tmp)

		return NULL;

	return (unsigned long *)base;

}

static void __init setup_vector(void)

{

	int i;

	unsigned long *ramvec, *ramvec_p;

	const h8300_vector *trap_entry;

	ramvec = get_vector_address();

	if (ramvec == NULL)

		panic("interrupt vector serup failed.");

	else

		pr_debug("virtual vector at 0x%p\n", ramvec);

	/* create redirect table */

	ramvec_p = ramvec;

	trap_entry = trap_table;

	for (i = 0; i < NR_IRQS; i++) {

		if (i < 12) {

			if (*trap_entry)

				*ramvec_p = VECTOR(*trap_entry);

			ramvec_p++;

			trap_entry++;

		} else

			*ramvec_p++ = REDIRECT(_interrupt_entry);

	}

	_interrupt_redirect_table = ramvec;

}

#else

void setup_vector(void)

{

	/* noting do */

}

#endif

void __init init_IRQ(void)

{

	setup_vector();

	irqchip_init();

}

asmlinkage void do_IRQ(int irq)

{

	irq_enter();

	generic_handle_irq(irq);

	irq_exit();

}

/*

 *  linux/arch/h8300/kernel/signal.c

 *

 *  Copyright (C) 1991, 1992  Linus Torvalds

 *

 * This file is subject to the terms and conditions of the GNU General Public

 * License.  See the file COPYING in the main directory of this archive

 * for more details.

 */

/*

 * uClinux H8/300 support by Yoshinori Sato <ysato@users.sourceforge.jp>

 *                and David McCullough <davidm@snapgear.com>

 *

 * Based on

 * Linux/m68k by Hamish Macdonald

 */

/*

 * ++roman (07/09/96): implemented signal stacks (specially for tosemu on

 * Atari :-) Current limitation: Only one sigstack can be active at one time.

 * If a second signal with SA_ONSTACK set arrives while working on a sigstack,

 * SA_ONSTACK is ignored. This behaviour avoids lots of trouble with nested

 * signal handlers!

 */

#include <linux/sched.h>

#include <linux/mm.h>

#include <linux/kernel.h>

#include <linux/signal.h>

#include <linux/syscalls.h>

#include <linux/errno.h>

#include <linux/wait.h>

#include <linux/ptrace.h>

#include <linux/unistd.h>

#include <linux/stddef.h>

#include <linux/highuid.h>

#include <linux/personality.h>

#include <linux/tty.h>

#include <linux/binfmts.h>

#include <linux/tracehook.h>

#include <asm/setup.h>

#include <asm/uaccess.h>

#include <asm/pgtable.h>

#include <asm/traps.h>

#include <asm/ucontext.h>

/*

 * Do a signal return; undo the signal stack.

 *

 * Keep the return code on the stack quadword aligned!

 * That makes the cache flush below easier.

 */

struct rt_sigframe {

	long dummy_er0;

	long dummy_vector;

#if defined(CONFIG_CPU_H8S)

	short dummy_exr;

#endif

	long dummy_pc;

	char *pretcode;

	struct siginfo *pinfo;

	void *puc;

	unsigned char retcode[8];

	struct siginfo info;

	struct ucontext uc;

	int sig;

} __packed __aligned(2);

static inline int

restore_sigcontext(struct sigcontext *usc, int *pd0)

{

	struct pt_regs *regs = current_pt_regs();

	int err = 0;

	unsigned int ccr;

	unsigned int usp;

	unsigned int er0;

	/* Always make any pending restarted system calls return -EINTR */

	current_thread_info()->restart_block.fn = do_no_restart_syscall;

	/* restore passed registers */

#define COPY(r)  do { err |= get_user(regs->r, &usc->sc_##r); } while (0)

	COPY(er1);

	COPY(er2);

	COPY(er3);

	COPY(er5);

	COPY(pc);

	ccr = regs->ccr & 0x10;

	COPY(ccr);

#undef COPY

	regs->ccr &= 0xef;

	regs->ccr |= ccr;

	regs->orig_er0 = -1;		/* disable syscall checks */

	err |= __get_user(usp, &usc->sc_usp);

	wrusp(usp);

	err |= __get_user(er0, &usc->sc_er0);

	*pd0 = er0;

	return err;

}

asmlinkage int sys_rt_sigreturn(void)

{

	unsigned long usp = rdusp();

	struct rt_sigframe *frame = (struct rt_sigframe *)(usp - 4);

	sigset_t set;

	int er0;

	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))

		goto badframe;

	if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))

		goto badframe;

	set_current_blocked(&set);

	if (restore_sigcontext(&frame->uc.uc_mcontext, &er0))

		goto badframe;

	if (restore_altstack(&frame->uc.uc_stack))

		goto badframe;

	return er0;

badframe:

	force_sig(SIGSEGV, current);

	return 0;

}

static int setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs,

			     unsigned long mask)

{

	int err = 0;

	err |= __put_user(regs->er0, &sc->sc_er0);

	err |= __put_user(regs->er1, &sc->sc_er1);

	err |= __put_user(regs->er2, &sc->sc_er2);

	err |= __put_user(regs->er3, &sc->sc_er3);

	err |= __put_user(regs->er4, &sc->sc_er4);

	err |= __put_user(regs->er5, &sc->sc_er5);

	err |= __put_user(regs->er6, &sc->sc_er6);

	err |= __put_user(rdusp(),   &sc->sc_usp);

	err |= __put_user(regs->pc,  &sc->sc_pc);

	err |= __put_user(regs->ccr, &sc->sc_ccr);

	err |= __put_user(mask,      &sc->sc_mask);

	return err;

}

static inline void __user *

get_sigframe(struct ksignal *ksig, struct pt_regs *regs, size_t frame_size)

{

	return (void __user *)((sigsp(rdusp(), ksig) - frame_size) & -8UL);

}

static int setup_rt_frame(struct ksignal *ksig, sigset_t *set,

			  struct pt_regs *regs)

{

	struct rt_sigframe *frame;

	int err = 0;

	unsigned char *ret;

	frame = get_sigframe(ksig, regs, sizeof(*frame));

	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))

		return -EFAULT;

	if (ksig->ka.sa.sa_flags & SA_SIGINFO)

		err |= copy_siginfo_to_user(&frame->info, &ksig->info);

	/* Create the ucontext.  */

	err |= __put_user(0, &frame->uc.uc_flags);

	err |= __put_user(0, &frame->uc.uc_link);

	err |= __save_altstack(&frame->uc.uc_stack, rdusp());

	err |= setup_sigcontext(&frame->uc.uc_mcontext, regs, set->sig[0]);

	err |= copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));

	if (err)

		return -EFAULT;

	/* Set up to return from userspace.  */

	ret = frame->retcode;

	if (ksig->ka.sa.sa_flags & SA_RESTORER)

		ret = (unsigned char *)(ksig->ka.sa.sa_restorer);

	else {

		/* sub.l er0,er0; mov.b #__NR_rt_sigreturn,r0l; trapa #0 */

		err |= __put_user(0x1a80f800 + (__NR_rt_sigreturn & 0xff),

				  (unsigned long *)(frame->retcode + 0));

		err |= __put_user(0x5700,

				  (unsigned short *)(frame->retcode + 4));

	}

	err |= __put_user(ret, &frame->pretcode);

	if (err)

		return -EFAULT;

	/* Set up registers for signal handler */

	wrusp((unsigned long) frame);

	regs->pc  = (unsigned long) ksig->ka.sa.sa_handler;

	regs->er0 = ksig->sig;

	regs->er1 = (unsigned long)&(frame->info);

	regs->er2 = (unsigned long)&frame->uc;

	regs->er5 = current->mm->start_data;	/* GOT base */

	return 0;

}

static void

handle_restart(struct pt_regs *regs, struct k_sigaction *ka)

{

	switch (regs->er0) {

	case -ERESTARTNOHAND:

		if (!ka)

			goto do_restart;

		regs->er0 = -EINTR;

		break;

	case -ERESTART_RESTARTBLOCK:

		if (!ka) {

			regs->er0 = __NR_restart_syscall;

			regs->pc -= 2;

		} else

			regs->er0 = -EINTR;

		break;

	case -ERESTARTSYS:

		if (!(ka->sa.sa_flags & SA_RESTART)) {

			regs->er0 = -EINTR;

			break;

		}

		/* fallthrough */

	case -ERESTARTNOINTR:

do_restart:

		regs->er0 = regs->orig_er0;

		regs->pc -= 2;

		break;

	}

}

/*

 * OK, we're invoking a handler

 */

static void

handle_signal(struct ksignal *ksig, struct pt_regs *regs)

{

	sigset_t *oldset = sigmask_to_save();

	int ret;

	/* are we from a system call? */

	if (regs->orig_er0 >= 0)

		handle_restart(regs, &ksig->ka);

	ret = setup_rt_frame(ksig, oldset, regs);

	signal_setup_done(ret, ksig, 0);

}

/*

 * Note that 'init' is a special process: it doesn't get signals it doesn't

 * want to handle. Thus you cannot kill init even with a SIGKILL even by

 * mistake.

 */

static void do_signal(struct pt_regs *regs)

{

	struct ksignal ksig;

	current->thread.esp0 = (unsigned long) regs;

	if (get_signal(&ksig)) {

		/* Whee!  Actually deliver the signal.  */

		handle_signal(&ksig, regs);

		return;

	}

	/* Did we come from a system call? */

	if (regs->orig_er0 >= 0)

		handle_restart(regs, NULL);

	/* If there's no signal to deliver, we just restore the saved mask.  */

	restore_saved_sigmask();

}

asmlinkage void do_notify_resume(struct pt_regs *regs, u32 thread_info_flags)

{

	if (thread_info_flags & _TIF_SIGPENDING)

		do_signal(regs);

	if (thread_info_flags & _TIF_NOTIFY_RESUME) {

		clear_thread_flag(TIF_NOTIFY_RESUME);

		tracehook_notify_resume(regs);

	}

}

/*

 * linux/arch/h8300/boot/traps.c -- general exception handling code

 * H8/300 support Yoshinori Sato <ysato@users.sourceforge.jp>

 *

 * Cloned from Linux/m68k.

 *

 * No original Copyright holder listed,

 * Probable original (C) Roman Zippel (assigned DJD, 1999)

 *

 * Copyright 1999-2000 D. Jeff Dionne, <jeff@rt-control.com>

 *

 * This file is subject to the terms and conditions of the GNU General Public

 * License.  See the file COPYING in the main directory of this archive

 * for more details.

 */

#include <linux/types.h>

#include <linux/sched.h>

#include <linux/kernel.h>

#include <linux/errno.h>

#include <linux/init.h>

#include <linux/module.h>

#include <linux/bug.h>

#include <asm/irq.h>

#include <asm/traps.h>

#include <asm/page.h>

static DEFINE_SPINLOCK(die_lock);

/*

 * this must be called very early as the kernel might

 * use some instruction that are emulated on the 060

 */

void __init base_trap_init(void)

{

}

void __init trap_init(void)

{

}

asmlinkage void set_esp0(unsigned long ssp)

{

	current->thread.esp0 = ssp;

}

/*

 *	Generic dumping code. Used for panic and debug.

 */

static void dump(struct pt_regs *fp)

{

	unsigned long	*sp;

	unsigned char	*tp;

	int		i;

	pr_info("\nCURRENT PROCESS:\n\n");

	pr_info("COMM=%s PID=%d\n", current->comm, current->pid);

	if (current->mm) {

		pr_info("TEXT=%08x-%08x DATA=%08x-%08x BSS=%08x-%08x\n",

			(int) current->mm->start_code,

			(int) current->mm->end_code,

			(int) current->mm->start_data,

			(int) current->mm->end_data,

			(int) current->mm->end_data,

			(int) current->mm->brk);

		pr_info("USER-STACK=%08x  KERNEL-STACK=%08lx\n\n",

			(int) current->mm->start_stack,

			(int) PAGE_SIZE+(unsigned long)current);

	}

	show_regs(fp);

	pr_info("\nCODE:");

	tp = ((unsigned char *) fp->pc) - 0x20;

	for (sp = (unsigned long *) tp, i = 0; (i < 0x40);  i += 4) {

		if ((i % 0x10) == 0)

			pr_info("\n%08x: ", (int) (tp + i));

		pr_info("%08x ", (int) *sp++);

	}

	pr_info("\n");

	pr_info("\nKERNEL STACK:");

	tp = ((unsigned char *) fp) - 0x40;

	for (sp = (unsigned long *) tp, i = 0; (i < 0xc0); i += 4) {

		if ((i % 0x10) == 0)

			pr_info("\n%08x: ", (int) (tp + i));

		pr_info("%08x ", (int) *sp++);

	}

	pr_info("\n");

	if (STACK_MAGIC != *(unsigned long *)((unsigned long)current+PAGE_SIZE))

		pr_info("(Possibly corrupted stack page??)\n");

	pr_info("\n\n");

}

void die(const char *str, struct pt_regs *fp, unsigned long err)

{

	static int diecount;

	oops_enter();

	console_verbose();

	spin_lock_irq(&die_lock);

	report_bug(fp->pc, fp);

	pr_crit("%s: %04lx [#%d] ", str, err & 0xffff, ++diecount);

	dump(fp);

	spin_unlock_irq(&die_lock);

	do_exit(SIGSEGV);

}

static int kstack_depth_to_print = 24;

void show_stack(struct task_struct *task, unsigned long *esp)

{

	unsigned long *stack,  addr;

	int i;

	if (esp == NULL)

		esp = (unsigned long *) &esp;

	stack = esp;

	pr_info("Stack from %08lx:", (unsigned long)stack);

	for (i = 0; i < kstack_depth_to_print; i++) {

		if (((unsigned long)stack & (THREAD_SIZE - 1)) == 0)

			break;

		if (i % 8 == 0)

			pr_info("\n       ");

		pr_info(" %08lx", *stack++);

	}

	pr_info("\nCall Trace:");

	i = 0;

	stack = esp;

	while (((unsigned long)stack & (THREAD_SIZE - 1)) != 0) {

		addr = *stack++;

		/*

		 * If the address is either in the text segment of the

		 * kernel, or in the region which contains vmalloc'ed

		 * memory, it *may* be the address of a calling

		 * routine; if so, print it so that someone tracing

		 * down the cause of the crash will be able to figure

		 * out the call path that was taken.

		 */

		if (check_kernel_text(addr)) {

			if (i % 4 == 0)

				pr_info("\n       ");

			pr_info(" [<%08lx>]", addr);

			i++;

		}

	}

	pr_info("\n");

}

void show_trace_task(struct task_struct *tsk)

{

	show_stack(tsk, (unsigned long *)tsk->thread.esp0);

}