This commit is contained in:
Imbus 2025-09-01 21:51:24 +02:00
parent 13b91e7aae
commit 3f74e55322
3 changed files with 1 additions and 91 deletions

74
riscv.h
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@ -1,74 +0,0 @@
#ifndef RISCV_KERNEL_H
#define RISCV_KERNEL_H
#include <types.h>
/** Page Size */
#define PGSIZE 4096 // bytes per page
// /** Page Shift, bits of offset within a page */
#define PGSHIFT 12
#define PGROUNDUP(sz) (((sz) + PGSIZE - 1) & ~(PGSIZE - 1))
#define PGROUNDDOWN(a) (((a)) & ~(PGSIZE - 1))
// Supervisor Status Register, sstatus
#define SSTATUS_SPP (1L << 8) /** Supervisor Previous Privilege 1=S, 0=U */
#define SSTATUS_SPIE (1L << 5) /** Supervisor Previous Interrupt Enable */
#define SSTATUS_UPIE (1L << 4) /** User Previous Interrupt Enable */
#define SSTATUS_SIE (1L << 1) /** Supervisor Interrupt Enable */
#define SSTATUS_UIE (1L << 0) /** User Interrupt Enable */
/** Page Table Entry Type */
typedef u64 pte_t;
/** Page Table Type */
typedef u64 *pagetable_t; // 512 PTEs
/** Returns the current hart id */
static inline u64 read_mhartid() {
u64 x;
asm volatile("csrr %0, mhartid" : "=r"(x));
return x;
}
/** Read thread pointer */
static inline u64 read_tp() {
u64 x;
asm volatile("mv %0, tp" : "=r"(x));
return x;
}
/** Write thread pointer */
static inline void write_tp(u64 x) { asm volatile("mv tp, %0" : : "r"(x)); }
/**
* Read the value of the sstatus register.
* (Supervisor Status Register)
*/
static inline u64 r_sstatus() {
u64 x;
asm volatile("csrr %0, sstatus" : "=r"(x));
return x;
}
/**
* Write a value to the sstatus register.
* (Supervisor Status Register)
*/
static inline void w_sstatus(u64 x) {
asm volatile("csrw sstatus, %0" : : "r"(x));
}
/** Enable device interrupts */
static inline void intr_on() { w_sstatus(r_sstatus() | SSTATUS_SIE); }
/** Disable device interrupts */
static inline void intr_off() { w_sstatus(r_sstatus() & ~SSTATUS_SIE); }
/** Are device interrupts enabled? */
static inline int intr_get() {
u64 x = r_sstatus();
return (x & SSTATUS_SIE) != 0;
}
#endif

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#include <memory.h>
#include <proc.h>
#include <riscv.h>
#include <types.h>
#include <stdint.h>
#include <uart.h>
/**

16
types.h
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#pragma once
typedef unsigned char u8;
typedef unsigned short u16;
typedef unsigned int u32;
typedef unsigned long u64;
typedef unsigned char uint8_t;
typedef unsigned short uint16_t;
typedef unsigned int uint32_t;
typedef unsigned long uint64_t;
typedef uint64_t size_t;
typedef uint64_t uintptr_t;
typedef u8 bool;