sw64: add exception handling support

/* SPDX-License-Identifier: GPL-2.0 */

#ifndef _ASM_SW64_KDEBUG_H

#define _ASM_SW64_KDEBUG_H

#include <linux/notifier.h>

enum die_val {

	DIE_OOPS = 1,

	DIE_BREAK,

	DIE_SSTEPBP,

	DIE_UPROBE,

	DIE_UPROBE_XOL,

};

#endif /* _ASM_SW64_KDEBUG_H */

/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */

#ifndef _UAPI_ASM_SW64_GENTRAP_H

#define _UAPI_ASM_SW64_GENTRAP_H

/*

 * Definitions for gentrap causes.  They are generated by user-level

 * programs and therefore should be compatible with the corresponding

 * legacy definitions.

 */

#define GEN_INTOVF	-1	/* integer overflow */

#define GEN_INTDIV	-2	/* integer division by zero */

#define GEN_FLTOVF	-3	/* fp overflow */

#define GEN_FLTDIV	-4	/* fp division by zero */

#define GEN_FLTUND	-5	/* fp underflow */

#define GEN_FLTINV	-6	/* invalid fp operand */

#define GEN_FLTINE	-7	/* inexact fp operand */

#define GEN_DECOVF	-8	/* decimal overflow (for COBOL??) */

#define GEN_DECDIV	-9	/* decimal division by zero */

#define GEN_DECINV	-10	/* invalid decimal operand */

#define GEN_ROPRAND	-11	/* reserved operand */

#define GEN_ASSERTERR	-12	/* assertion error */

#define GEN_NULPTRERR	-13	/* null pointer error */

#define GEN_STKOVF	-14	/* stack overflow */

#define GEN_STRLENERR	-15	/* string length error */

#define GEN_SUBSTRERR	-16	/* substring error */

#define GEN_RANGERR	-17	/* range error */

#define GEN_SUBRNG	-18

#define GEN_SUBRNG1	-19

#define GEN_SUBRNG2	-20

#define GEN_SUBRNG3	-21	/* these report range errors for */

#define GEN_SUBRNG4	-22	/* subscripting (indexing) at levels 0..7 */

#define GEN_SUBRNG5	-23

#define GEN_SUBRNG6	-24

#define GEN_SUBRNG7	-25

/* the remaining codes (-26..-1023) are reserved. */

#endif /* _UAPI_ASM_SW64_GENTRAP_H */

/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */

/*

 * include/asm/sysinfo.h

 */

#ifndef _UAPI_ASM_SW64_SYSINFO_H

#define _UAPI_ASM_SW64_SYSINFO_H

#define GSI_IEEE_FP_CONTROL		45

#define SSI_IEEE_FP_CONTROL		14

#define SSI_IEEE_RAISE_EXCEPTION	1001	/* linux specific */

#define UAC_BITMASK			7

#define UAC_NOPRINT			1

#define UAC_NOFIX			2

#define UAC_SIGBUS			4

#define PR_NOFIX			4	/* do not fix up unaligned accesses */

#endif /* _UAPI_ASM_SW64_SYSINFO_H */

// SPDX-License-Identifier: GPL-2.0

#include <asm/debug.h>

#include <linux/debugfs.h>

#include <linux/slab.h>

#include <linux/uaccess.h>

unsigned long unaligned_count;

char unaligned_task[TASK_COMM_LEN];

struct unaligned_stat unaligned[UNA_MAX_ENTRIES];

static ssize_t unaligned_set(struct file *file, const char __user *user_buf,

			size_t len, loff_t *ppos)

{

	size_t size;

	unaligned_count = 0;

	size = min(sizeof(unaligned_task), len);

	if (copy_from_user(unaligned_task, user_buf, size))

		return -EFAULT;

	unaligned_task[size - 1] = '\0';

	return len;

}

static int unaligned_show(struct seq_file *m, void *v)

{

	int i, idx, nr;

	if (!unaligned_task[0]) {

		seq_puts(m, "No task traced\n");

		return 0;

	}

	seq_printf(m, "Task command:\t\t%s\n", unaligned_task);

	seq_printf(m, "Unaligned count:\t%ld\n", unaligned_count);

	if (!unaligned_count)

		return 0;

	nr = 0;

	idx = unaligned_count % UNA_MAX_ENTRIES;

	seq_printf(m, "Latest %d unaligned stat:\nNo.\tVA\t\tPC\n", UNA_MAX_ENTRIES);

	if (unaligned_count >= UNA_MAX_ENTRIES) {

		for (i = idx; i < UNA_MAX_ENTRIES; i++)

			seq_printf(m, "%d\t%#lx\t%#lx\n",

					nr++, unaligned[i].va, unaligned[i].pc);

	}

	for (i = 0; i < idx; i++)

		seq_printf(m, "%d\t%#lx\t%#lx\n",

				nr++, unaligned[i].va, unaligned[i].pc);

	return 0;

}

static int unaligned_open(struct inode *inode, struct file *file)

{

	return single_open(file, unaligned_show, NULL);

}

static const struct file_operations unaligned_fops = {

	.read		= seq_read,

	.write		= unaligned_set,

	.open		= unaligned_open,

	.llseek		= default_llseek,

};

static int __init unaligned_init(void)

{

	struct dentry *unaligned;

	if (!sw64_debugfs_dir)

		return -ENODEV;

	unaligned = debugfs_create_file("unaligned", 0644,

			sw64_debugfs_dir, NULL,

			&unaligned_fops);

	if (!unaligned)

		return -ENOMEM;

	return 0;

}

late_initcall(unaligned_init);