/* SPDX-License-Identifier: GPL-2.0 */
/*
 * thread_info.h: LoongArch low-level thread information
 *
 * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
 */

#ifndef _ASM_THREAD_INFO_H
#define _ASM_THREAD_INFO_H

#ifdef __KERNEL__

#ifndef __ASSEMBLER__

#include <asm/processor.h>

/*
 * 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
 */
struct thread_info {
        struct task_struct      *task;          /* main task structure */
        unsigned long           flags;          /* low level flags */
        unsigned long           tp_value;       /* thread pointer */
        __u32                   cpu;            /* current CPU */
        int                     preempt_count;  /* 0 => preemptible, <0 => BUG */
        struct pt_regs          *regs;
        unsigned long           syscall;        /* syscall number */
        unsigned long           syscall_work;   /* SYSCALL_WORK_ flags */
};

/*
 * macros/functions for gaining access to the thread information structure
 */
#define INIT_THREAD_INFO(tsk)                   \
{                                               \
        .task           = &tsk,                 \
        .flags          = _TIF_FIXADE,          \
        .cpu            = 0,                    \
        .preempt_count  = INIT_PREEMPT_COUNT,   \
}

/* How to get the thread information struct from C. */
register struct thread_info *__current_thread_info __asm__("$tp");

static inline struct thread_info *current_thread_info(void)
{
        return __current_thread_info;
}

register unsigned long current_stack_pointer __asm__("$sp");

#endif /* !__ASSEMBLER__ */

/* thread information allocation */
#define THREAD_SIZE             SZ_16K
#define THREAD_MASK             (THREAD_SIZE - 1UL)
#define THREAD_SIZE_ORDER       ilog2(THREAD_SIZE / PAGE_SIZE)
/*
 * 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
 *
 * Tell the generic TIF infrastructure which special bits loongarch supports
 */
#define HAVE_TIF_NEED_RESCHED_LAZY
#define HAVE_TIF_RESTORE_SIGMASK

#include <asm-generic/thread_info_tif.h>

/* Architecture specific bits */
#define TIF_NOHZ                16      /* in adaptive nohz mode */
#define TIF_USEDFPU             17      /* FPU was used by this task this quantum (SMP) */
#define TIF_USEDSIMD            18      /* SIMD has been used this quantum */
#define TIF_FIXADE              19      /* Fix address errors in software */
#define TIF_LOGADE              20      /* Log address errors to syslog */
#define TIF_32BIT_REGS          21      /* 32-bit general purpose registers */
#define TIF_32BIT_ADDR          22      /* 32-bit address space */
#define TIF_LOAD_WATCH          23      /* If set, load watch registers */
#define TIF_SINGLESTEP          24      /* Single Step */
#define TIF_LSX_CTX_LIVE        25      /* LSX context must be preserved */
#define TIF_LASX_CTX_LIVE       26      /* LASX context must be preserved */
#define TIF_USEDLBT             27      /* LBT was used by this task this quantum (SMP) */
#define TIF_LBT_CTX_LIVE        28      /* LBT context must be preserved */

#define _TIF_NOHZ               BIT(TIF_NOHZ)
#define _TIF_USEDFPU            BIT(TIF_USEDFPU)
#define _TIF_USEDSIMD           BIT(TIF_USEDSIMD)
#define _TIF_FIXADE             BIT(TIF_FIXADE)
#define _TIF_LOGADE             BIT(TIF_LOGADE)
#define _TIF_32BIT_REGS         BIT(TIF_32BIT_REGS)
#define _TIF_32BIT_ADDR         BIT(TIF_32BIT_ADDR)
#define _TIF_LOAD_WATCH         BIT(TIF_LOAD_WATCH)
#define _TIF_SINGLESTEP         BIT(TIF_SINGLESTEP)
#define _TIF_LSX_CTX_LIVE       BIT(TIF_LSX_CTX_LIVE)
#define _TIF_LASX_CTX_LIVE      BIT(TIF_LASX_CTX_LIVE)
#define _TIF_USEDLBT            BIT(TIF_USEDLBT)
#define _TIF_LBT_CTX_LIVE       BIT(TIF_LBT_CTX_LIVE)

#endif /* __KERNEL__ */
#endif /* _ASM_THREAD_INFO_H */