add x86 supportHEADmaster

4 files changed, 145 insertions, 0 deletions

diff --git a/kernel/x86/kernel.c b/kernel/x86/kernel.c
new file mode 100644
index 0000000..296d966
--- /dev/null
+++ b/kernel/x86/kernel.c
@@ -0,0 +1,30 @@
+#include <sys/stddef.h>
+#include <early/uart.h>
+#include <sys/log.h>
+
+#define COM1_PORT 0x3F8
+
+void serial_init(void) {
+    outb(COM1_PORT + 1, 0x00);    // Disable interrupts
+    outb(COM1_PORT + 3, 0x80);    // Enable DLAB (set baud rate divisor)
+    outb(COM1_PORT + 0, 0x01);    // Set divisor to 1 (lo byte) -> 115200 baud
+    outb(COM1_PORT + 1, 0x00);    //                  (hi byte)
+    outb(COM1_PORT + 3, 0x03);    // 8 bits, no parity, one stop bit
+    outb(COM1_PORT + 2, 0xC7);    // Enable FIFO, clear them, with 14-byte threshold
+    outb(COM1_PORT + 4, 0x0B);    // IRQs enabled, RTS/DSR set
+}
+
+static int serial_tx_ready(void) {
+    return inb(COM1_PORT + 5) & 0x20;
+}
+
+void serial_putchar(char c) {
+    while (serial_tx_ready() == 0);
+    outb(COM1_PORT, c);
+}
+
+void kernel_main(void) {
+    serial_init();
+    register_console_callback(serial_putchar);
+    printk("wkern version %s (Compiler %s, Linker %s) on %s\n", VERSION, COMPILER_NAME, LINKER_NAME, ARCH_NAME);
+}
diff --git a/kernel/x86/linker.ld b/kernel/x86/linker.ld
new file mode 100644
index 0000000..067d4e4
--- /dev/null
+++ b/kernel/x86/linker.ld
@@ -0,0 +1,87 @@
+OUTPUT_ARCH(i386:x86-64)
+ENTRY(_start)
+
+MEMORY
+{
+    ROM   (rx)  : ORIGIN = 0x1000000, LENGTH = 1M
+    RAM   (rwx) : ORIGIN = 0x1040000, LENGTH = 1M
+    LOGRAM (rw) : ORIGIN = 0x1080000, LENGTH = 1M
+}
+
+SECTIONS
+{
+    .header : {
+        KEEP(*(.header))
+        *(.header)
+    } > ROM
+
+    .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
+
+    .ringbuf (NOLOAD) : ALIGN(64)
+    {
+        __ringbuf_start = .;
+        KEEP(*(.ringbuf))
+        . = ALIGN(64);
+        __ringbuf_end = .;
+    } > LOGRAM
+
+    .image_end (NOLOAD) : {
+        . = ALIGN(4);
+        __image_end = .;
+    } > ROM
+
+    /DISCARD/ : {
+        *(.eh_frame)
+        *(.eh_frame.*)
+        *(.eh_frame_hdr)
+        *(.comment)
+        *(.note.*)
+        *(.debug_*)
+        *(.stab*)
+        *(.llvm_*)
+        *(.rela.*)
+    }
+
+    __image_start = ORIGIN(ROM);
+    __image_size = __image_end - __image_start;
+}
diff --git a/kernel/x86/start.S b/kernel/x86/start.S
new file mode 100644
index 0000000..779657c
--- /dev/null
+++ b/kernel/x86/start.S
@@ -0,0 +1,10 @@
+.section .text._start
+.global _start
+
+_start:
+    call kernel_main
+1:
+    cli
+    hlt
+    jmp 1b
+
diff --git a/kernel/x86/uart.S b/kernel/x86/uart.S
new file mode 100644
index 0000000..416fad2
--- /dev/null
+++ b/kernel/x86/uart.S
@@ -0,0 +1,18 @@
+.section .text
+
+.global outb
+.global inb
+
+# void outb(uint16_t port, uint8_t val)
+outb:
+    mov %dl, %al
+    mov %cx, %dx
+    outb %al, %dx
+    ret
+
+# uint8_t inb(uint16_t port)
+inb:
+    mov %cx, %dx
+    inb %dx, %al
+    ret
+