diff options
| -rw-r--r-- | Makefile | 36 | ||||
| -rw-r--r-- | include/endian.h | 17 | ||||
| -rw-r--r-- | include/stddef.h | 7 | ||||
| -rw-r--r-- | include/stdint.h | 19 | ||||
| -rw-r--r-- | include/string.h | 8 | ||||
| -rw-r--r-- | lib/Makefile | 21 | ||||
| -rw-r--r-- | lib/build/memset.o | bin | 0 -> 1328 bytes | |||
| -rw-r--r-- | lib/string/memset.c | 14 | ||||
| -rw-r--r-- | mainboard/virt/conf/mainboard.conf | 4 | ||||
| -rw-r--r-- | sys/Makefile | 36 | ||||
| -rw-r--r-- | sys/dev/sbi.c | 39 | ||||
| -rw-r--r-- | sys/include/fdt.h | 37 | ||||
| -rw-r--r-- | sys/include/kernel_earlyprintf.h | 6 | ||||
| -rw-r--r-- | sys/include/mm/kalloc.h | 11 | ||||
| -rw-r--r-- | sys/include/sbi.h | 16 | ||||
| -rw-r--r-- | sys/kern/entry.S (renamed from kernel/boot/entry.S) | 23 | ||||
| -rw-r--r-- | sys/kern/init.c | 11 | ||||
| -rw-r--r-- | sys/kern/kernel.lds (renamed from kernel/lds/kernel.ld) | 15 | ||||
| -rw-r--r-- | sys/kern/kernel_earlyprintf.c | 11 | ||||
| -rw-r--r-- | sys/kern/mm/kalloc.c | 40 |
20 files changed, 337 insertions, 34 deletions
@@ -1,30 +1,22 @@ TARGET?=virt CROSS_COMPILE?=riscv64-unknown-elf- +GDB_PORT?=1234 +CFLAGS=-nostdlib -ffreestanding -mcmodel=medany -nostdinc -I${.CURDIR}/include +.export -BUILDDIR=build/${TARGET} -TARGETDIR=mainboard/${TARGET} +sys: ${SRC} lib/build/libc.a + @echo "building kernel" + (${MAKE} -C sys -e) -CFLAGS=-nostdlib -ffreestanding -mcmodel=medany +lib/build/libc.a: + @echo "building libc" + (${MAKE} -C lib -e) -.if !exists(${TARGETDIR}/conf/mainboard.mk) -.error 'ERROR: invalid target "${TARGET}"' -.else -.include <${TARGETDIR}/conf/mainboard.mk> -.endif - -all: ${BUILDDIR}/kernel.elf +debug: sys + (${MAKE} -C sys -e debug) clean: - rm -rf ${BUILDDIR} - -${BUILDDIR}/kernel.elf: ${SRC} - mkdir -p ${BUILDDIR} - ${CROSS_COMPILE}gcc ${SRC} \ - -Wl,--defsym=LOAD_ADDR=${LOAD_ADDR}\ - -Wl,--defsym=PAGE_SIZE=${PAGE_SIZE}\ - -Wl,--defsym=NPROC=${NPROC}\ - -DPAGE_SIZE=${PAGE_SIZE}\ - ${CFLAGS} -T kernel/lds/kernel.ld ${LDFLAGS}\ - -o $@ + (${MAKE} -C sys -e clean) + (${MAKE} -C lib -e clean) -.PHONY: all clean +.PHONY: sys debug all clean diff --git a/include/endian.h b/include/endian.h new file mode 100644 index 0000000..79b4c93 --- /dev/null +++ b/include/endian.h @@ -0,0 +1,17 @@ +#ifndef _ENDIAN_H +#define _ENDIAN_H + +#include <stdint.h> + +#define LITTLE_ENDIAN 1234 +#define BIG_ENDIAN 4321 +#define BYTE_ORDER __BYTE_ORDER__ + +static inline uint32_t +__bswap32(uint32_t x) +{ + uint8_t *p = (uint8_t*)&x; + return ((p[0] << 030) | (p[1] << 020) | (p[2] << 010) | p[3]); +} + +#endif /* _ENDIAN_H */ diff --git a/include/stddef.h b/include/stddef.h new file mode 100644 index 0000000..998f53d --- /dev/null +++ b/include/stddef.h @@ -0,0 +1,7 @@ +#ifndef _STDDEF_H +#define _STDDEF_H + +#define NULL ((void*)0) +typedef unsigned long size_t; + +#endif /* _STDDEF_H_ */ diff --git a/include/stdint.h b/include/stdint.h new file mode 100644 index 0000000..4afd32d --- /dev/null +++ b/include/stdint.h @@ -0,0 +1,19 @@ +#ifndef _STDINT_H +#define _STDINT_H + + +typedef unsigned char uint8_t; +typedef unsigned short uint16_t; +typedef unsigned int uint32_t; +typedef unsigned long uint64_t; + + +typedef char int8_t; +typedef short int16_t; +typedef int int32_t; +typedef long int64_t; + + +#endif /* _STDINT_H */ + + diff --git a/include/string.h b/include/string.h new file mode 100644 index 0000000..a8edd63 --- /dev/null +++ b/include/string.h @@ -0,0 +1,8 @@ +#ifndef _STRING_H +#define _STRING_H + +#include <stddef.h> + +void *memset(void *s, int c, size_t n); + +#endif /* _STRING_H */ diff --git a/lib/Makefile b/lib/Makefile new file mode 100644 index 0000000..b44c1f6 --- /dev/null +++ b/lib/Makefile @@ -0,0 +1,21 @@ +BUILDDIR=build/${TARGET} +TARGETDIR=../mainboard/${TARGET} + +.if !exists(${TARGETDIR}/conf/mainboard.conf) +.error 'ERROR: invalid target "${TARGET}"' +.else +.include <${TARGETDIR}/conf/mainboard.conf> +.endif + +SRC=\ + string/memset.c + + +${BUILDDIR}/libc.a: ${SRC} + mkdir -p ${BUILDDIR} + cd ${BUILDDIR} && ${CROSS_COMPILE}gcc -c ${CFLAGS} ${SRC:%=../../%} + cd ${BUILDDIR} && ${CROSS_COMPILE}ar -rcs ${@:T} ${SRC:T:%.c=%.o} + + +clean: + rm -rf ${BUILDDIR} diff --git a/lib/build/memset.o b/lib/build/memset.o Binary files differnew file mode 100644 index 0000000..a5c0c8c --- /dev/null +++ b/lib/build/memset.o diff --git a/lib/string/memset.c b/lib/string/memset.c new file mode 100644 index 0000000..59e3bea --- /dev/null +++ b/lib/string/memset.c @@ -0,0 +1,14 @@ +#include <stddef.h> +#include <string.h> + +void * +memset(void *s, int c, size_t n) +{ + char *xs = s; + + while (n--) + *xs++ = c; + + return s; +} + diff --git a/mainboard/virt/conf/mainboard.conf b/mainboard/virt/conf/mainboard.conf new file mode 100644 index 0000000..77e8e2a --- /dev/null +++ b/mainboard/virt/conf/mainboard.conf @@ -0,0 +1,4 @@ +LOAD_ADDR=0x80200000 +PAGE_SIZE=4096 +NPROC=1 +DEBUG=qemu-system-riscv64 -nographic -machine virt -smp ${NPROC} -m 128M -bios default -gdb tcp::${GDB_PORT} -kernel diff --git a/sys/Makefile b/sys/Makefile new file mode 100644 index 0000000..865a5a3 --- /dev/null +++ b/sys/Makefile @@ -0,0 +1,36 @@ +BUILDDIR=build/${TARGET} +TARGETDIR=../mainboard/${TARGET} + +.if !exists(${TARGETDIR}/conf/mainboard.conf) +.error 'ERROR: invalid target "${TARGET}"' +.else +.include <${TARGETDIR}/conf/mainboard.conf> +.endif + +SRC=\ + kern/entry.S\ + kern/init.c\ + kern/kernel_earlyprintf.c\ + kern/mm/kalloc.c\ + dev/sbi.c + +${BUILDDIR}/kernel.elf: ${SRC} + mkdir -p ${BUILDDIR} + ${CROSS_COMPILE}gcc ${SRC} \ + -Wl,--defsym=LOAD_ADDR=${LOAD_ADDR}\ + -Wl,--defsym=PAGE_SIZE=${PAGE_SIZE}\ + -Wl,--defsym=NPROC=${NPROC}\ + -DPAGE_SIZE=${PAGE_SIZE}\ + -I ./include\ + ${CFLAGS} -T kern/kernel.lds ${LDFLAGS}\ + -L../lib/${BUILDDIR}/\ + -l:libc.a\ + -o $@ + +debug: ${BUILDDIR}/kernel.elf + ${DEBUG} ${BUILDDIR}/kernel.elf + +clean: + rm -rf ${BUILDDIR} + +.PHONY: debug clean diff --git a/sys/dev/sbi.c b/sys/dev/sbi.c new file mode 100644 index 0000000..0c9e3f2 --- /dev/null +++ b/sys/dev/sbi.c @@ -0,0 +1,39 @@ +#include <sbi.h> + +struct sbiret +sbi_ecall(int ext, int fid, unsigned long arg0, + unsigned long arg1, unsigned long arg2, + unsigned long arg3, unsigned long arg4, + unsigned long arg5) +{ + struct sbiret ret; + + register unsigned long a0 asm ("a0") = (unsigned long)(arg0); + register unsigned long a1 asm ("a1") = (unsigned long)(arg1); + register unsigned long a2 asm ("a2") = (unsigned long)(arg2); + register unsigned long a3 asm ("a3") = (unsigned long)(arg3); + register unsigned long a4 asm ("a4") = (unsigned long)(arg4); + register unsigned long a5 asm ("a5") = (unsigned long)(arg5); + register unsigned long a6 asm ("a6") = (unsigned long)(fid); + register unsigned long a7 asm ("a7") = (unsigned long)(ext); + asm volatile ("ecall" + : "+r" (a0), "+r" (a1) + : "r" (a2), "r" (a3), "r" (a4), "r" (a5), "r" (a6), "r" (a7) + : "memory"); + ret.err = a0; + ret.val = a1; + + return ret; +} + +void +sbi_console_putchar(int c) +{ + sbi_ecall(1, 0, c, 0, 0, 0, 0, 0); +} + +void +sbi_shutdown(void) +{ + sbi_ecall(8, 0, 0, 0, 0, 0, 0, 0); +} diff --git a/sys/include/fdt.h b/sys/include/fdt.h new file mode 100644 index 0000000..92e5695 --- /dev/null +++ b/sys/include/fdt.h @@ -0,0 +1,37 @@ +#include <stdint.h> +#include <endian.h> + +#ifndef _FDT_H +#define _FDT_H + +#define FDT_HEADER_MAGIC 0xd00dfeed + +static inline uint32_t +fdt_uint32(uint32_t x) +{ +#if BYTE_ORDER == LITTLE_ENDIAN +return __bswap32(x); +#else +return x; +#endif +} + +struct fdt_header { + uint32_t magic; /* FDT_HEADER_MAGIC */ + uint32_t totalsize; /* size of the whole device tree, in bytes */ + uint32_t off_dt_struct; /* offset to structure block */ + uint32_t off_dt_strings; /* offset to strings block */ + uint32_t off_mem_rsvmap; /* offset to memory reservation block */ + uint32_t version; /* dt spec version */ + uint32_t last_comp_version; /* last compatible version. spec says this needs to be 16 */ + uint32_t boot_cpuid_phys; /* physical id of the systems boot cpu */ + uint32_t size_dt_strings; /* size of strings block */ + uint32_t size_dt_struct; /* size of structure block */ +}; + +struct fdt_reserve_entry { + uint64_t address; + uint64_t size; +}; + +#endif /* _FDT_H */ diff --git a/sys/include/kernel_earlyprintf.h b/sys/include/kernel_earlyprintf.h new file mode 100644 index 0000000..051d7e5 --- /dev/null +++ b/sys/include/kernel_earlyprintf.h @@ -0,0 +1,6 @@ +#ifndef _KPRINTF_H +#define _KPRINTF_H + +int kernel_earlyputs(const char *); + +#endif /* _KPRINTF_H */ diff --git a/sys/include/mm/kalloc.h b/sys/include/mm/kalloc.h new file mode 100644 index 0000000..e99d624 --- /dev/null +++ b/sys/include/mm/kalloc.h @@ -0,0 +1,11 @@ +#ifndef _KALLOC_H +#define _KALLOC_H + +void *kalloc(void); + +void *kzalloc(void); + +void kfree(void *); + +#endif /* _KALLOC_H */ + diff --git a/sys/include/sbi.h b/sys/include/sbi.h new file mode 100644 index 0000000..0dbcd02 --- /dev/null +++ b/sys/include/sbi.h @@ -0,0 +1,16 @@ +#ifndef _SBICALL_H +#define _SBICALL_H + +struct sbiret { + long err; + long val; +}; + +struct sbiret sbi_ecall(int _eid, int _fid, unsigned long _a0, unsigned long _a1, + unsigned long _a2, unsigned long _a3, unsigned long _a4, unsigned long _a5); + +void sbi_console_putchar(int c); +void sbi_shutdown(void); + +#endif /* _SBICALL_H */ + diff --git a/kernel/boot/entry.S b/sys/kern/entry.S index 4c977a3..5ad0490 100644 --- a/kernel/boot/entry.S +++ b/sys/kern/entry.S @@ -1,4 +1,4 @@ -.section .text.init +.section ".text.init" .globl _start _start: @@ -12,25 +12,28 @@ _start: .option pop la sp, __stack_start - mv t0, a0 li t1, PAGE_SIZE - mul t0, t0, t1 - add sp, sp, t0 + mul t1, t1, a0 + add sp, sp, t1 li a2, 1 lla a3, _boot_hart - amoswap.w, a3, a2, (a3) - bnez a3, mp_entry + amoswap.w a3, a2, (a3) + bnez a3, _spin la a2, __bss_start la a3, __bss_end 1: - sd zero, (a2) + sd zero, (a2) addi a2, a2, __SIZEOF_POINTER__ blt a2, a3, 1b - call boot + call init -_boot_hart: - .dword 0 +_spin: + wfi + j _spin + +.section ".data" +_boot_hart: .word 0 diff --git a/sys/kern/init.c b/sys/kern/init.c new file mode 100644 index 0000000..a49c304 --- /dev/null +++ b/sys/kern/init.c @@ -0,0 +1,11 @@ +#include <fdt.h> +#include <kernel_earlyprintf.h> + +void +init(unsigned long hartid, struct fdt_header *fdt) +{ + kernel_earlyputs("booting...\n"); + if (fdt_uint32(fdt->magic) == FDT_HEADER_MAGIC) + kernel_earlyputs("found flattened device tree!\n"); + +} diff --git a/kernel/lds/kernel.ld b/sys/kern/kernel.lds index 052aa32..2e2fe29 100644 --- a/kernel/lds/kernel.ld +++ b/sys/kern/kernel.lds @@ -8,13 +8,13 @@ SECTIONS .text : { - provide(__text_start = .); + PROVIDE(__text_start = .); *(.text.init) *(.text .text.*) . = ALIGN(8); PROVIDE(__text_end = .); } - . = ALIGN(PAGE_SIZE); + . = ALIGN(PAGE_SIZE); PROVIDE(__global_pointer$ = .); @@ -41,6 +41,17 @@ SECTIONS . = ALIGN(PAGE_SIZE); + .bss : + { + PROVIDE(__bss_start = .); + *(.sbss .sbss.*) + *(.bss .bss.*) + . = ALIGN(8); + PROVIDE(__bss_end = .); + } + + . = ALIGN(PAGE_SIZE); + PROVIDE(__stack_start = .); PROVIDE(__stack_end = __stack_start + (PAGE_SIZE * NPROC)); PROVIDE(__heap_start = __stack_end); diff --git a/sys/kern/kernel_earlyprintf.c b/sys/kern/kernel_earlyprintf.c new file mode 100644 index 0000000..e6c85c4 --- /dev/null +++ b/sys/kern/kernel_earlyprintf.c @@ -0,0 +1,11 @@ +#include <kernel_earlyprintf.h> +#include <sbi.h> + +int +kernel_earlyputs(const char *str) +{ + do { + sbi_console_putchar(*str); + } while (*(str++) != '\0'); +} + diff --git a/sys/kern/mm/kalloc.c b/sys/kern/mm/kalloc.c new file mode 100644 index 0000000..b17d432 --- /dev/null +++ b/sys/kern/mm/kalloc.c @@ -0,0 +1,40 @@ +#include <stddef.h> +#include <string.h> +#include <mm/kalloc.h> + +typedef struct freenode { + struct freenode *next; +} freenode_t; + +freenode_t *head = NULL; + +void * +kalloc(void) +{ + freenode_t *p = head; + + if (p == NULL) + return NULL; + + head = p->next; + return p; +} + +void * +kzalloc(void) +{ + freenode_t *p = kalloc(); + memset(p, 0, PAGE_SIZE); + return p; +} + +void +kfree(void *p) +{ + if (p == NULL || (unsigned long)p % PAGE_SIZE) + return; + + freenode_t *tmp = head; + head = p; + head->next = tmp; +} |