include/arch/riscv/thread.h

/*
 * Copyright (c) 2017 Intel Corporation
 *
 * SPDX-License-Identifier: Apache-2.0
 */

/**
 * @file
 * @brief Per-arch thread definition
 *
 * This file contains definitions for
 *
 *  struct _thread_arch
 *  struct _callee_saved
 *
 * necessary to instantiate instances of struct k_thread.
 */

#ifndef ZEPHYR_INCLUDE_ARCH_RISCV_THREAD_H_
#define ZEPHYR_INCLUDE_ARCH_RISCV_THREAD_H_

#ifndef _ASMLANGUAGE
#include <zephyr/types.h>

#if !defined(RV_FP_TYPE) && defined(CONFIG_FPU) && defined(CONFIG_FPU_SHARING)
#ifdef CONFIG_CPU_HAS_FPU_DOUBLE_PRECISION
#define RV_FP_TYPE uint64_t
#else
#define RV_FP_TYPE uint32_t
#endif
#endif

#ifdef CONFIG_RISCV_PMP
#ifdef CONFIG_64BIT
#define	RISCV_PMP_CFG_NUM	(CONFIG_PMP_SLOT >> 3)
#else
#define	RISCV_PMP_CFG_NUM	(CONFIG_PMP_SLOT >> 2)
#endif
#endif

#ifdef CONFIG_PMP_STACK_GUARD
/*
 * PMP entries:
 *   (1 for interrupt stack guard: None)
 *   4 for stacks guard: None
 *   1 for RAM: RW
 *   1 for other address space: RWX
 */
#define PMP_REGION_NUM_FOR_STACK_GUARD	6
#define PMP_CFG_CSR_NUM_FOR_STACK_GUARD	2
#endif /* CONFIG_PMP_STACK_GUARD */

/*
 * The following structure defines the list of registers that need to be
 * saved/restored when a context switch occurs.
 */
struct _callee_saved {
	ulong_t sp;	/* Stack pointer, (x2 register) */
	ulong_t ra;	/* return address */
	ulong_t tp;	/* thread pointer */

	ulong_t s0;	/* saved register/frame pointer */
	ulong_t s1;	/* saved register */
	ulong_t s2;	/* saved register */
	ulong_t s3;	/* saved register */
	ulong_t s4;	/* saved register */
	ulong_t s5;	/* saved register */
	ulong_t s6;	/* saved register */
	ulong_t s7;	/* saved register */
	ulong_t s8;	/* saved register */
	ulong_t s9;	/* saved register */
	ulong_t s10;	/* saved register */
	ulong_t s11;	/* saved register */

#if defined(CONFIG_FPU) && defined(CONFIG_FPU_SHARING)
	uint32_t fcsr;		/* Control and status register */
	RV_FP_TYPE fs0;		/* saved floating-point register */
	RV_FP_TYPE fs1;		/* saved floating-point register */
	RV_FP_TYPE fs2;		/* saved floating-point register */
	RV_FP_TYPE fs3;		/* saved floating-point register */
	RV_FP_TYPE fs4;		/* saved floating-point register */
	RV_FP_TYPE fs5;		/* saved floating-point register */
	RV_FP_TYPE fs6;		/* saved floating-point register */
	RV_FP_TYPE fs7;		/* saved floating-point register */
	RV_FP_TYPE fs8;		/* saved floating-point register */
	RV_FP_TYPE fs9;		/* saved floating-point register */
	RV_FP_TYPE fs10;	/* saved floating-point register */
	RV_FP_TYPE fs11;	/* saved floating-point register */
#endif
};
typedef struct _callee_saved _callee_saved_t;

struct _thread_arch {
#ifdef CONFIG_PMP_STACK_GUARD
	ulong_t s_pmpcfg[PMP_CFG_CSR_NUM_FOR_STACK_GUARD];
	ulong_t s_pmpaddr[PMP_REGION_NUM_FOR_STACK_GUARD];
#endif

#ifdef CONFIG_USERSPACE
	ulong_t priv_stack_start;
	ulong_t u_pmpcfg[RISCV_PMP_CFG_NUM];
	ulong_t u_pmpaddr[CONFIG_PMP_SLOT];
#endif
};

typedef struct _thread_arch _thread_arch_t;

#endif /* _ASMLANGUAGE */

#endif /* ZEPHYR_INCLUDE_ARCH_RISCV_THREAD_H_ */