/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
 * OpenRISC Linux
 *
 * Linux architectural port borrowing liberally from similar works of
 * others.  All original copyrights apply as per the original source
 * declaration.
 *
 * OpenRISC implementation:
 * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
 * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
 * et al.
 */

#ifndef _ASM_THREAD_INFO_H
#define _ASM_THREAD_INFO_H

#ifdef __KERNEL__

#ifndef __ASSEMBLER__
#include <asm/types.h>
#include <asm/processor.h>
#endif


/* THREAD_SIZE is the size of the task_struct/kernel_stack combo.
 * normally, the stack is found by doing something like p + THREAD_SIZE
 * in or1k, a page is 8192 bytes, which seems like a sane size
 */

#define THREAD_SIZE_ORDER 0
#define THREAD_SIZE       (PAGE_SIZE << THREAD_SIZE_ORDER)

/*
 * low level task data that entry.S needs immediate access to
 * - this struct should fit entirely inside of one cache line
 * - this struct shares the supervisor stack pages
 * - if the contents of this structure are changed, the assembly constants
 *   must also be changed
 */
#ifndef __ASSEMBLER__

struct thread_info {
        struct task_struct      *task;          /* main task structure */
        unsigned long           flags;          /* low level flags */
        __u32                   cpu;            /* current CPU */
        __s32                   preempt_count; /* 0 => preemptable, <0 => BUG */

        __u8                    supervisor_stack[0];

        /* saved context data */
        unsigned long           ksp;
};
#endif

/*
 * macros/functions for gaining access to the thread information structure
 *
 * preempt_count needs to be 1 initially, until the scheduler is functional.
 */
#ifndef __ASSEMBLER__
#define INIT_THREAD_INFO(tsk)                           \
{                                                       \
        .task           = &tsk,                         \
        .flags          = 0,                            \
        .cpu            = 0,                            \
        .preempt_count  = INIT_PREEMPT_COUNT,           \
        .ksp            = 0,                            \
}

/* how to get the thread information struct from C */
register struct thread_info *current_thread_info_reg asm("r10");
#define current_thread_info()   (current_thread_info_reg)

#define get_thread_info(ti) get_task_struct((ti)->task)
#define put_thread_info(ti) put_task_struct((ti)->task)

#endif /* !__ASSEMBLER__ */

/*
 * thread information flags
 *   these are process state flags that various assembly files may need to
 *   access
 *   - pending work-to-be-done flags are in LSW
 *   - other flags in MSW
 */
#define TIF_SYSCALL_TRACE       0       /* syscall trace active */
#define TIF_NOTIFY_RESUME       1       /* resumption notification requested */
#define TIF_SIGPENDING          2       /* signal pending */
#define TIF_NEED_RESCHED        3       /* rescheduling necessary */
#define TIF_SINGLESTEP          4       /* restore singlestep on return to user
                                         * mode
                                         */
#define TIF_NOTIFY_SIGNAL       5       /* signal notifications exist */
#define TIF_SYSCALL_TRACEPOINT  8       /* for ftrace syscall instrumentation */
#define TIF_RESTORE_SIGMASK     9
#define TIF_POLLING_NRFLAG      16      /* true if poll_idle() is polling                                                * TIF_NEED_RESCHED
                                         */
#define TIF_MEMDIE              17

#define _TIF_SYSCALL_TRACE      (1<<TIF_SYSCALL_TRACE)
#define _TIF_NOTIFY_RESUME      (1<<TIF_NOTIFY_RESUME)
#define _TIF_SIGPENDING         (1<<TIF_SIGPENDING)
#define _TIF_NEED_RESCHED       (1<<TIF_NEED_RESCHED)
#define _TIF_SINGLESTEP         (1<<TIF_SINGLESTEP)
#define _TIF_NOTIFY_SIGNAL      (1<<TIF_NOTIFY_SIGNAL)
#define _TIF_POLLING_NRFLAG     (1<<TIF_POLLING_NRFLAG)


/* Work to do when returning from interrupt/exception */
/* For OpenRISC, this is anything in the LSW other than syscall trace */
#define _TIF_WORK_MASK (0xff & ~(_TIF_SYSCALL_TRACE|_TIF_SINGLESTEP))

#endif /* __KERNEL__ */

#endif /* _ASM_THREAD_INFO_H */