Merge branch 'main' of github.com:dzwdz/camellia

6 files changed, 174 insertions, 31 deletions

diff --git a/src/kernel/arch/i386/ata.c b/src/kernel/arch/i386/ata.c
new file mode 100644
index 0000000..9224ed6
--- /dev/null
+++ b/src/kernel/arch/i386/ata.c
@@ -0,0 +1,131 @@
+#include <kernel/arch/i386/ata.h>
+#include <kernel/arch/i386/port_io.h>
+#include <kernel/panic.h>
+#include <stdbool.h>
+
+#include <kernel/arch/io.h>
+
+static struct {
+	enum {
+		DEV_UNKNOWN,
+		DEV_PATA,
+		DEV_PATAPI,
+	} type;
+	uint32_t sectors;
+} ata_drives[4];
+
+enum {
+	LBAlo  = 3,
+	LBAmid = 4,
+	LBAhi  = 5,
+	DRV    = 6,
+	CMD    = 7,
+	STATUS = 7,
+
+	/* note: the OSDev wiki uses a different base port for the control port
+	 *       however i can just use this offset and stuff will just work tm */
+	CTRL   = 0x206,
+}; // offsets
+
+// get I/O port base for drive
+static uint16_t ata_iobase(int drive) {
+	bool secondary = drive&2;
+	return secondary ? 0x170 : 0x1F0;
+}
+
+static void ata_400ns(void) {
+	uint16_t base = ata_iobase(0); // doesn't matter
+	for (int i = 0; i < 4; i++)
+		port_in8(base + STATUS);
+}
+
+static void ata_driveselect(int drive, int block) {
+	uint8_t v = 0xE0;
+	if (drive&1) // slave?
+		v |= 0x10; // set drive number bit
+	// TODO account for block
+	port_out8(ata_iobase(drive) + DRV, v);
+}
+
+static void ata_softreset(int drive) {
+	uint16_t iobase = ata_iobase(drive);
+	port_out8(iobase + CTRL, 4);
+	port_out8(iobase + CTRL, 0);
+	ata_400ns();
+
+	uint16_t timeout = 10000;
+	while (--timeout) { // TODO separate polling function
+		uint8_t v = port_in8(iobase + STATUS);
+		if (v & 0x80) continue; // still BSY, continue
+		if (v & 0x40) break; // RDY, break
+		// TODO check for ERR
+	}
+}
+
+static void ata_detecttype(int drive) {
+	ata_softreset(drive);
+	ata_driveselect(drive, 0);
+	ata_400ns();
+	switch (port_in8(ata_iobase(drive) + LBAmid)) {
+		case 0:
+			ata_drives[drive].type = DEV_PATA;
+			break;
+		case 0x14:
+			ata_drives[drive].type = DEV_PATAPI;
+			break;
+		default:
+			ata_drives[drive].type = DEV_UNKNOWN;
+			break;
+	}
+}
+
+static bool ata_identify(int drive) {
+	uint16_t iobase = ata_iobase(drive);
+	uint16_t data[256];
+	uint8_t v;
+
+	ata_driveselect(drive, 0);
+	for (int i = 2; i < 6; i++)
+		port_out8(iobase + i, 0);
+	switch (ata_drives[drive].type) {
+		case DEV_PATA:
+			port_out8(iobase + CMD, 0xEC); // IDENTIFY
+			break;
+		case DEV_PATAPI:
+			port_out8(iobase + CMD, 0xA1); // IDENTIFY PACKET DEVICE
+			break;
+		default: panic_invalid_state();
+	}
+
+	v = port_in8(iobase + STATUS);
+	if (v == 0) return false; // nonexistent drive
+	while (port_in8(iobase + STATUS) & 0x80);
+
+	/* pool until bit 3 (DRQ) or 0 (ERR) is set */
+	while (!((v = port_in8(iobase + STATUS) & 0x9)));
+	if (v & 1) return false; /* ERR was set, bail */
+
+	for (int i = 0; i < 256; i++)
+		data[i] = port_in16(iobase);
+	ata_drives[drive].sectors = data[60] | (data[61] << 16);
+	return true;
+}
+
+void ata_init(void) {
+	tty_const("\n");
+	for (int i = 0; i < 4; i++) {
+		tty_const("probing drive ");
+		_tty_var(i);
+		ata_detecttype(i);
+		if (ata_drives[i].type != DEV_UNKNOWN) {
+			if (ata_identify(i)) {
+				tty_const(" - ");
+				_tty_var(ata_drives[i].sectors);
+				tty_const(" sectors (512b)");
+			} else {
+				tty_const(" identify failed");
+			}
+		}
+		tty_const("\n");
+	}
+}
diff --git a/src/kernel/arch/i386/ata.h b/src/kernel/arch/i386/ata.h
new file mode 100644
index 0000000..9137cdb
--- /dev/null
+++ b/src/kernel/arch/i386/ata.h
@@ -0,0 +1,4 @@
+#pragma once
+#include <stdint.h>
+
+void ata_init(void);
diff --git a/src/kernel/arch/i386/boot.c b/src/kernel/arch/i386/boot.c
index bd2a00b..94e9e2f 100644
--- a/src/kernel/arch/i386/boot.c
+++ b/src/kernel/arch/i386/boot.c
@@ -1,4 +1,5 @@
 #include <kernel/arch/generic.h>
+#include <kernel/arch/i386/ata.h>
 #include <kernel/arch/i386/boot.h>
 #include <kernel/arch/i386/gdt.h>
 #include <kernel/arch/i386/interrupts/idt.h>
@@ -15,7 +16,9 @@ void kmain_early(struct multiboot_info *multiboot) {
 	gdt_init();
 	tty_const("idt...");
 	idt_init();
-	
+	tty_const("ata...");
+	ata_init();
+
 	{ // find the init module
 		struct multiboot_mod *module = &multiboot->mods[0];
 		if (multiboot->mods_count < 1) {
@@ -25,6 +28,6 @@ void kmain_early(struct multiboot_info *multiboot) {
 		info.init.at   = module->start;
 		info.init.size = module->end - module->start;
 	}
-	
+
 	kmain(info);
 }
diff --git a/src/kernel/arch/i386/interrupts/isr.c b/src/kernel/arch/i386/interrupts/isr.c
index dacecba..9d8bb6c 100644
--- a/src/kernel/arch/i386/interrupts/isr.c
+++ b/src/kernel/arch/i386/interrupts/isr.c
@@ -1,29 +1,24 @@
 #include <kernel/arch/i386/interrupts/isr.h>
 #include <kernel/arch/io.h>
 #include <kernel/panic.h>
+#include <kernel/proc.h>
 #include <stdbool.h>
 #include <stdint.h>
 
-#define log_n_panic(x) {tty_const(x); panic_unimplemented();} // TODO kill the current process instead of panicking
-
 bool isr_test_interrupt_called = false;
 
 void isr_stage3(int interrupt) {
 	switch (interrupt) {
-		case 0x08: log_n_panic("#DF"); // double fault
-		case 0x0D: log_n_panic("#GP"); // general protection fault
-		case 0x0E: { // page fault
-			int cr2;
-			tty_const("#PF at ");
-			asm ("mov %%cr2, %0;" : "=r"(cr2) ::);
-			_tty_var(cr2);
-			panic_unimplemented();
-		}
-
+		case 0x08: // double fault
+			tty_const("#DF");
+			panic_invalid_state();
 		case 0x34:
 			isr_test_interrupt_called = true;
 			return;
 
-		default:   log_n_panic("unknown interrupt");
+		default:
+			// TODO check if the exception was in the kernel
+			process_kill(process_current, interrupt);
+			process_switch_any();
 	}
 }
diff --git a/src/kernel/arch/i386/port_io.h b/src/kernel/arch/i386/port_io.h
index a4d640f..eac9331 100644
--- a/src/kernel/arch/i386/port_io.h
+++ b/src/kernel/arch/i386/port_io.h
@@ -1,12 +1,22 @@
 #include <stdint.h>
 
-static inline void port_outb(uint16_t port, uint8_t val) {
+static inline void port_out8(uint16_t port, uint8_t val) {
 	asm volatile("outb %0, %1" : : "a" (val), "Nd" (port));
 }
 
-static inline uint8_t port_inb(uint16_t port) {
+static inline void port_out16(uint16_t port, uint16_t val) {
+	asm volatile("outw %0, %1" : : "a" (val), "Nd" (port));
+}
+
+static inline uint8_t port_in8(uint16_t port) {
 	uint8_t val;
 	asm volatile("inb %1, %0" : "=a" (val) : "Nd" (port));
 	return val;
 }
 
+static inline uint16_t port_in16(uint16_t port) {
+	uint16_t val;
+	asm volatile("inw %1, %0" : "=a" (val) : "Nd" (port));
+	return val;
+}
+
diff --git a/src/kernel/arch/i386/tty/serial.c b/src/kernel/arch/i386/tty/serial.c
index 2b89ecf..f9bb252 100644
--- a/src/kernel/arch/i386/tty/serial.c
+++ b/src/kernel/arch/i386/tty/serial.c
@@ -7,37 +7,37 @@ static const int COM1 = 0x3f8;
 
 static void serial_selftest(void) {
 	char b = 0x69;
-	port_outb(COM1 + 4, 0b00011110); // enable loopback mode
-	port_outb(COM1, b);
-	assert(port_inb(COM1) == b);
+	port_out8(COM1 + 4, 0b00011110); // enable loopback mode
+	port_out8(COM1, b);
+	assert(port_in8(COM1) == b);
 }
 
 void serial_init(void) {
 	// see https://www.sci.muni.cz/docs/pc/serport.txt
 
-	port_outb(COM1 + 1, 0x00); // disable interrupts, we won't be using them
+	port_out8(COM1 + 1, 0x00); // disable interrupts, we won't be using them
 
 	// set baud rate divisor
-	port_outb(COM1 + 3, 0b10000000); // enable DLAB
-	port_outb(COM1 + 0, 0x01);       // divisor = 1 (low  byte)
-	port_outb(COM1 + 1, 0x00);       //             (high byte)
+	port_out8(COM1 + 3, 0b10000000); // enable DLAB
+	port_out8(COM1 + 0, 0x01);       // divisor = 1 (low  byte)
+	port_out8(COM1 + 1, 0x00);       //             (high byte)
 
-	port_outb(COM1 + 3, 0b00000011); // 8 bits, no parity, one stop bit
-	port_outb(COM1 + 2, 0b11000111); // enable FIFO with 14-bit trigger level (???)
+	port_out8(COM1 + 3, 0b00000011); // 8 bits, no parity, one stop bit
+	port_out8(COM1 + 2, 0b11000111); // enable FIFO with 14-bit trigger level (???)
 
 	serial_selftest();
 
-	port_outb(COM1 + 4, 0b00001111); // enable everything in the MCR
+	port_out8(COM1 + 4, 0b00001111); // enable everything in the MCR
 }
 
 static void serial_putchar(char c) {
-	while ((port_inb(COM1 + 5) & 0x20) == 0); // wait for THRE
-	port_outb(COM1, c);
+	while ((port_in8(COM1 + 5) & 0x20) == 0); // wait for THRE
+	port_out8(COM1, c);
 }
 
 char serial_read(void) {
-	while ((port_inb(COM1 + 5) & 0x01) == 0); // wait for DR
-	return port_inb(COM1);
+	while ((port_in8(COM1 + 5) & 0x01) == 0); // wait for DR
+	return port_in8(COM1);
 }
 
 void serial_write(const char *buf, size_t len) {