tiny-os/kernel.h at main · bskdany/tiny-os · GitHub

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#pragma once
#include "common.h"

struct sbi_ret {
    long err;
    long val;
};

/* encloded in a dead do-while loop for scope purposes */
/* the second while loop halts everything */
#define PANIC(fmt, ...)                                                                                                \
    do {                                                                                                               \
        printf("PANIC: %s:%d: " fmt "\n", __FILE__, __LINE__, ##__VA_ARGS__);                                          \
        while (1) {                                                                                                    \
        }                                                                                                              \
    } while (0)

/* panic stuff */
struct trap_frame {
    uint32_t ra;
    uint32_t gp;
    uint32_t tp;
    uint32_t t0;
    uint32_t t1;
    uint32_t t2;
    uint32_t t3;
    uint32_t t4;
    uint32_t t5;
    uint32_t t6;
    uint32_t a0;
    uint32_t a1;
    uint32_t a2;
    uint32_t a3;
    uint32_t a4;
    uint32_t a5;
    uint32_t a6;
    uint32_t a7;
    uint32_t s0;
    uint32_t s1;
    uint32_t s2;
    uint32_t s3;
    uint32_t s4;
    uint32_t s5;
    uint32_t s6;
    uint32_t s7;
    uint32_t s8;
    uint32_t s9;
    uint32_t s10;
    uint32_t s11;
    uint32_t sp;
} __attribute__((packed));

#define READ_CSR(reg)                                                                                                  \
    ({                                                                                                                 \
        unsigned long __tmp;                                                                                           \
        __asm__ __volatile__("csrr %0, " #reg : "=r"(__tmp));                                                          \
        __tmp;                                                                                                         \
    })

#define WRITE_CSR(reg, value)                                                                                          \
    do {                                                                                                               \
        uint32_t __tmp = (value);                                                                                      \
        __asm__ __volatile__("csrw " #reg ", %0" ::"r"(__tmp));                                                        \
    } while (0)

#define PROCS_MAX 8 /* max num of processes */
#define PROC_UNUSED 0
#define PROC_RUNNABLE 1
#define PROC_EXITED 2

struct process {
    int pid;
    int state;  /* unused or rumnnable */
    vaddr_t sp; /* stack pointer */
    uint32_t *page_table;
    uint8_t stack[8192]; /* kernel stack */
};

#define SATP_SV32 (1u << 31) /* internal flag */
#define PAGE_V (1 << 0)      // "Valid" bit (entry is enabled)
#define PAGE_R (1 << 1)      // Readable
#define PAGE_W (1 << 2)      // Writable
#define PAGE_X (1 << 3)      // Executable
#define PAGE_U (1 << 4)      // User (accessible in user mode)

/* base addres of app */
#define USER_BASE 0x1000000

#define SSTATUS_SPIE (1 << 5)

#define SCAUSE_ECALL 8