scaffold kernel from parts of wkern x86

10 files changed, 334 insertions, 1 deletions

diff --git a/.gitignore b/.gitignore
index 92d2735..be664a6 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,7 @@
 website-emu/target
 website-emu/Cargo.lock
-.idea/
\ No newline at end of file
+website-emu/pkg
+
+website-kernel/compile_commands.json
+
+.idea/
diff --git a/website-emu/Cargo.toml b/website-emu/Cargo.toml
index 575b12b..9dc8fcd 100644
--- a/website-emu/Cargo.toml
+++ b/website-emu/Cargo.toml
@@ -3,5 +3,8 @@ name = "website-emu"
 version = "0.1.0"
 edition = "2024"
 
+[lib]
+crate-type = ["cdylib", "rlib"]
+
 [dependencies]
 wasm-bindgen = "0.2"
diff --git a/website-emu/src/lib.rs b/website-emu/src/lib.rs
index 7c1a285..ffaa677 100644
--- a/website-emu/src/lib.rs
+++ b/website-emu/src/lib.rs
@@ -11,9 +11,42 @@ const REGISTER_NAME_WIDTH: u32 = 0b11111;
 
 const DRAM_LOAD: u32 = 0x20000000;
 const OS_LOAD: u32 = 0x80000000;
+
+const CONSOLE_LOAD: u32 = 0x70000000;
+
 const INITRD_LOAD: u32 = 0;
 
 #[wasm_bindgen]
+extern "C" {
+    #[wasm_bindgen(js_namespace = console)]
+    fn log(s: &str);
+}
+
+pub struct Uart {
+    pub addr: u32,
+    pub value: u8
+}
+
+impl MemoryDevice for Uart {
+    fn read(&self, address: u32) -> Result<u8, ()> {
+        if (address == self.addr) {
+            Ok(self.value)
+        } else {
+            Err(())
+        }
+    }
+
+    fn write(&mut self, address: u32, value: u8) -> Result<(), ()> {
+        if (address == self.addr) {
+            self.value = value;
+            Ok(())
+        } else {
+            Err(())
+        }
+    }
+}
+
+#[wasm_bindgen]
 pub fn boot(image: &[u8], initrd: &[u8], memory: &[u8]) {
     let mut cpu_memory = CpuMemory {
         devices: Vec::new(),
@@ -41,10 +74,27 @@ pub fn boot(image: &[u8], initrd: &[u8], memory: &[u8]) {
         dram: initrd.to_vec().into_boxed_slice(),
     };
 
+    let uart = Uart {
+        addr: CONSOLE_LOAD,
+        value: 0
+    };
+
     cpu_memory.register_device(
         DRAM_LOAD..DRAM_LOAD + memory_len as u32,
         Box::new(ram_device)
     );
+    cpu_memory.register_device(
+        OS_LOAD..OS_LOAD + os_size as u32,
+        Box::new(os_image)
+    );
+    cpu_memory.register_device(
+        INITRD_LOAD..INITRD_LOAD + initrd_size as u32,
+        Box::new(initrd_image)
+    );
+    cpu_memory.register_device(
+        CONSOLE_LOAD..CONSOLE_LOAD + 1,
+        Box::new(uart)
+    );
 
     let mut state = CpuState::new(cpu_memory);
 
diff --git a/website-kernel/Makefile b/website-kernel/Makefile
new file mode 100644
index 0000000..eb5a76e
--- /dev/null
+++ b/website-kernel/Makefile
@@ -0,0 +1,73 @@
+CC = clang
+LD = ld.lld
+OBJCOPY = llvm-objcopy
+
+COMPILER = $(shell $(CC) --version | head -n 1)
+LINKER = $(shell $(LD) --version | head -n 1)
+ARCH_NAME = 32-bit RISC-V, IM_Zicsr ISA, little endian, unknown ELF, System V ABI
+
+CFLAGS = \
+	--target=riscv32-unknown-elf \
+	-march=rv32im_zicsr \
+	-mabi=ilp32 \
+	-ffreestanding \
+	-fno-builtin \
+	-nostdlib \
+	-nostdinc \
+	-nodefaultlibs \
+	-DVERSION='"$(VERSION)"' \
+	-DCOMPILER_NAME='"$(COMPILER)"' \
+	-DLINKER_NAME='"$(LINKER)"' \
+	-DARCH_NAME='"$(ARCH_NAME)"' \
+	-static \
+	-ffunction-sections -fdata-sections -fno-common \
+	-Iinclude -O2 -g3 \
+	-Wall -Wextra -Werror -Wundef
+
+LD_FLAGS = \
+	-T $(LINKER_SCRIPT) -nostdlib -m elf32lriscv --gc-sections
+
+OBJCOPY_FLAGS = \
+	-O binary \
+	--strip-all \
+	--remove-section=.comment \
+	--remove-section=.debug* \
+	--remove-section=.note* \
+	--remove-section=.eh_frame \
+	--remove-section=.eh_frame_ptr \
+	--remove-section=.eh_frame_hdr
+
+C_SRCS = $(shell find . -name '*.c')
+S_SRCS = $(shell find . -name '*.S')
+C_OBJECTS = $(C_SRCS:.c=.o)
+S_OBJECTS = $(S_SRCS:.S=.o)
+ALL_OBJECTS = $(C_OBJECTS) $(S_OBJECTS)
+LINKER_SCRIPT = arch/linker.ld
+
+KERNEL_BINARY = Image.bin
+KERNEL_ELF = arch/webos-kernel.elf
+
+$(V).SILENT:
+
+%.o: %.c
+	@echo " CC $<"
+	$(CC) $(CFLAGS) -c $< -o $@
+%.o: %.S
+	@echo " AS $<"
+	$(CC) $(CFLAGS) -c $< -o $@
+$(KERNEL_ELF): $(ALL_OBJECTS)  $(LINKER_SCRIPT)
+	@echo " LD $@"
+	$(LD) $(LD_FLAGS) -o $@ $(ALL_OBJECTS)
+$(KERNEL_BINARY): $(KERNEL_ELF)
+	@echo " OBJCOPY $@"
+	$(OBJCOPY) $(OBJCOPY_FLAGS) $(KERNEL_ELF) $(KERNEL_BIN)
+clean:
+	@echo " CLEAN $(ALL_OBJECTS)"
+	$(RM) $(ALL_OBJECTS)
+	@echo " CLEAN $(KERNEL_ELF)"
+	$(RM) $(KERNEL_ELF)
+	@echo " CLEAN $(KERNEL_BINARY)"
+	$(RM) $(KERNEL_BINARY)
+
+.PHONY: all clean
+all: $(KERNEL_BINARY)
diff --git a/website-kernel/arch/kernel.c b/website-kernel/arch/kernel.c
new file mode 100644
index 0000000..28c94d3
--- /dev/null
+++ b/website-kernel/arch/kernel.c
@@ -0,0 +1,9 @@
+#include <int.h>
+#include <log.h>
+
+#define SERIAL_PORT 0x70000000
+
+void kernel_main(size_t hart) {
+    (void)hart;
+    printk("wkern version %s (Compiler %s, Linker %s) on %s\n", VERSION, COMPILER_NAME, LINKER_NAME, ARCH_NAME);
+}
diff --git a/website-kernel/arch/linker.ld b/website-kernel/arch/linker.ld
new file mode 100644
index 0000000..52a3a05
--- /dev/null
+++ b/website-kernel/arch/linker.ld
@@ -0,0 +1,52 @@
+OUTPUT_ARCH(riscv)
+ENTRY(_start)
+
+MEMORY
+{
+    ROM (rx) : ORIGIN = 0x80000000, LENGTH = 1M
+    RAM (rwx) : ORIGIN = 0x20000000, LENGTH = 4M
+}
+
+SECTIONS
+{
+    .text : {
+        KEEP(*(.text._start))
+        KEEP(*(.text.start))
+        *(.text)
+        *(.text.*)
+    } > ROM
+    .rodata : {
+        *(.rodata)
+        *(.rodata.*)
+    } > ROM
+
+    .init_array : {
+        __init_array_start = .;
+        KEEP(*(.init_array))
+        KEEP(*(.init_array.*))
+        __init_array_end = .;
+    } > ROM
+
+    .data : {
+        __data_start = .;
+        *(.data)
+        *(.data.*)
+        __data_end = .;
+    } > RAM AT> ROM
+    __data_load = LOADADDR(.data);
+
+    .bss : {
+        __bss_start = .;
+        *(.bss)
+        *(.bss.*)
+        *(COMMON)
+        __bss_end = .;
+    } > RAM
+
+    .stack (NOLOAD) : {
+        . = ALIGN(16);
+        __stack_bottom = .;
+        . += 8K;
+        __stack_top = .;
+    } > RAM
+}
diff --git a/website-kernel/arch/log.c b/website-kernel/arch/log.c
new file mode 100644
index 0000000..63e0615
--- /dev/null
+++ b/website-kernel/arch/log.c
@@ -0,0 +1,100 @@
+#include <log.h>
+void stub(char c) {
+    (void)c;
+    return;
+}
+
+console_callback_t callback = stub;
+
+void put_char(char c) {
+    callback(c);
+}
+
+void put_string(const char *s) {
+    while (*s)
+        put_char(*s++);
+}
+
+void put_uint(unsigned int value, unsigned int radix) {
+    char tmp[16];
+    const char digits[] = "0123456789abcdef";
+    int i = 0;
+
+    if (value == 0) {
+        put_char('0');
+        return;
+    }
+
+    while (value) {
+        tmp[i++] = digits[value % radix];
+        value /= radix;
+    }
+
+    while (i--)
+        put_char(tmp[i]);
+}
+
+void put_int(int value) {
+    if (value < 0) {
+        put_char('-');
+        put_uint((unsigned int)(-value), 10);
+    } else {
+        put_uint((unsigned int)value, 10);
+    }
+}
+
+void vprintk(const char *fmt, __builtin_va_list args) {
+    while (*fmt) {
+        if (*fmt != '%') {
+            put_char(*fmt++);
+            continue;
+        }
+
+        fmt++;
+
+        switch (*fmt) {
+        case '%':
+            put_char('%');
+            break;
+
+        case 'c':
+            put_char((char)__builtin_va_arg(args, int));
+            break;
+
+        case 's':
+            put_string(__builtin_va_arg(args, const char *));
+            break;
+
+        case 'd':
+        case 'i':
+            put_int(__builtin_va_arg(args, int));
+            break;
+
+        case 'u':
+            put_uint(__builtin_va_arg(args, unsigned int), 10);
+            break;
+
+        case 'x':
+            put_uint(__builtin_va_arg(args, unsigned int), 16);
+            break;
+
+        default:
+            put_char('%');
+            put_char(*fmt);
+            break;
+        }
+
+        fmt++;
+    }
+}
+
+void printk(const char *fmt, ...) {
+    __builtin_va_list args;
+    __builtin_va_start(args, fmt);
+    vprintk(fmt, args);
+    __builtin_va_end(args);
+}
+
+void register_console_callback(console_callback_t cb) {
+    callback = cb;
+}
diff --git a/website-kernel/arch/start.S b/website-kernel/arch/start.S
new file mode 100644
index 0000000..8248ab9
--- /dev/null
+++ b/website-kernel/arch/start.S
@@ -0,0 +1,23 @@
+.section .text._start
+.global _start
+.type _start, @function
+
+.extern user_regs
+
+_start:
+    csrw sstatus, zero
+    csrw sie, zero
+
+    la sp, __stack_top
+    
+    la t0, __bss_start
+    la t1, __bss_end
+    beq t0, t1, 2f
+1:
+    sw zero, 0(t0)
+    addi t0, t0, 4
+    bltu t0, t1, 1b
+2:
+    call kernel_main
+    wfi
+
diff --git a/website-kernel/include/int.h b/website-kernel/include/int.h
new file mode 100644
index 0000000..2a378e7
--- /dev/null
+++ b/website-kernel/include/int.h
@@ -0,0 +1,8 @@
+#pragma once
+#define NULL (void*)0
+
+typedef __UINTPTR_TYPE__ size_t;
+typedef __UINT8_TYPE__ uint8_t;
+typedef __UINT16_TYPE__ uint16_t;
+typedef __UINT32_TYPE__ uint32_t;
+typedef __UINT64_TYPE__ uint64_t;
diff --git a/website-kernel/include/log.h b/website-kernel/include/log.h
new file mode 100644
index 0000000..4312baf
--- /dev/null
+++ b/website-kernel/include/log.h
@@ -0,0 +1,11 @@
+#pragma once
+
+#define RINGBUF_SIZE 64 * 1024
+
+typedef void (*console_callback_t)(char);
+
+void vprintk(const char *message, __builtin_va_list args);
+void printk(const char *message, ...);
+
+void register_console_callback(console_callback_t callback);
+