core/kernel.h

@@ -11,6 +11,25 @@
 #define PTR_ALIGN(p, a) ((typeof(p))ALIGN((unsigned long)(p), (a)))
 #define IS_ALIGNED(x, a) (((x) & ((typeof(x))(a)-1)) == 0)
 
+
+#ifdef __CHECKER__
+#define BUILD_BUG_ON_ZERO(e) (0)
+#else /* __CHECKER__ */
+/*
+ * Force a compilation error if condition is true, but also produce a
+ * result (of value 0 and type int), so the expression can be used
+ * e.g. in a structure initializer (or where-ever else comma expressions
+ * aren't permitted).
+ */
+#define BUILD_BUG_ON_ZERO(e) ((int)(sizeof(struct { int:(-!!(e)); })))
+#endif /* __CHECKER__ */
+/* Are two types/vars the same type (ignoring qualifiers)? */
+#ifndef __same_type
+# define __same_type(a, b) __builtin_types_compatible_p(typeof(a), typeof(b))
+#endif
+/* &a[0] degrades to a pointer: a different type from an array */
+#define __must_be_array(a)	BUILD_BUG_ON_ZERO(__same_type((a), &(a)[0]))
+
 #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr))
 
 /*

core/main.c

@@ -1,5 +1,6 @@
 #include "alloc.h"
 #include "allocArea.h"
+#include "ata.h"
 #include "exception.h"
 #include "gdt.h"
 #include "idt.h"
@@ -152,6 +153,8 @@ void kmain(unsigned long magic, unsigned long addr)
     kthreadCreate("idle ", idleThread, NULL);
 
     irqSetRoutine(IRQ_TIMER, pit_handler);
+
+    ATAInit();
 #ifdef RUN_TEST
     run_test();
 #endif

drivers/ata.c

@@ -0,0 +1,71 @@
+#include "ata.h"
+#include "io.h"
+#include "kernel.h"
+#include "klibc.h"
+
+static struct ata_drive drives[4];
+
+int ATADectectType(struct ata_drive *drive)
+{
+	outb(drive->base + ATA_PIO_DRIVE, 0xA0 | drive->isSlave << 4);
+	outb(drive->base + ATA_PIO_SEC_COUNT, 0x0);
+	outb(drive->base + ATA_PIO_LBALO, 0x0);
+	outb(drive->base + ATA_PIO_LBAMID, 0x0);
+	outb(drive->base + ATA_PIO_LBAHI, 0x0);
+	outb(drive->base + ATA_PIO_CMD, ATA_PIO_CMD_IDENTIFY);
+	unsigned st = inb(drive->base + ATA_PIO_STATUS);
+	if(st & ATA_PIO_STATUS_DRIVE_BUSY)
+		goto no_disk;
+
+	inb(drive->dev_ctl); /* Drop the next 4 read to wait */
+	inb(drive->dev_ctl);
+	inb(drive->dev_ctl);
+	inb(drive->dev_ctl);
+	unsigned cl = inb(drive->base + ATA_PIO_LBAMID); /* get the "signature bytes" */
+	unsigned ch = inb(drive->base + ATA_PIO_LBAHI);
+
+	/* differentiate ATA, ATAPI, SATA and SATAPI */
+	if (cl == 0x14 && ch == 0xEB) {
+		drive->status = ATA_DEV_PATAPI;
+		return 0;
+	}
+	if (cl == 0x69 && ch == 0x96) {
+		drive->status = ATA_DEV_SATAPI;
+		return 0;
+	}
+	if (cl == 0 && ch == 0) {
+		drive->status = ATA_DEV_PATA;
+		return 0;
+	}
+	if (cl == 0x3c && ch == 0xc3) {
+		drive->status = ATA_DEV_SATA;
+		return 0;
+	}
+no_disk:
+	drive->status = ATA_DEV_UNKNOWN;
+	return -1;
+}
+
+int ATAInit()
+{
+	memset(drives, 0, sizeof(drives));
+	drives[0].base = 0x1F0;
+	drives[0].dev_ctl = 0x3F6;
+	drives[0].isSlave = 0;
+	drives[1].base = 0x1F0;
+	drives[1].dev_ctl = 0x3F6;
+	drives[1].isSlave = 1;
+	drives[1].base = 0x170;
+	drives[1].dev_ctl = 0x376;
+	drives[1].isSlave = 0;
+	drives[2].base = 0x170;
+	drives[2].dev_ctl = 0x376;
+	drives[2].isSlave = 1;
+
+	for(uint i = 0; i < ARRAY_SIZE(drives); i++){
+		if(!ATADectectType(&drives[i])){
+			printf("Driver %d detected %d\n", i, drives[i].status);
+		}
+	}
+	return 0;
+}

drivers/ata.h

@@ -0,0 +1,52 @@
+#pragma once
+#include "stdarg.h"
+
+#define ATA_PIO_REG_DATA 0
+#define ATA_PIO_REG_ERR 1
+#define ATA_PIO_REG_FEAT 1
+#define ATA_PIO_SEC_COUNT 2
+#define ATA_PIO_LBALO 3
+#define ATA_PIO_LBAMID 4
+#define ATA_PIO_CYL_LOW 4
+#define ATA_PIO_LBAHI 5
+#define ATA_PIO_CYL_HI 5
+#define ATA_PIO_DRIVE 6
+#define ATA_PIO_STATUS 7
+#define ATA_PIO_CMD 7
+
+#define ATA_PIO_CMD_IDENTIFY 0xEC
+
+#define ATA_PIO_ERROR_ADDR_MARK_NOT_FOUND 0
+#define ATA_PIO_ERROR_TRACK_ZERO_NOT_FOUND 1
+#define ATA_PIO_ERROR_ABORTED 2
+#define ATA_PIO_ERROR_MEDIA_CHANGE_REQUEST 3
+#define ATA_PIO_ERROR_ID_NOT_FOUND 4
+#define ATA_PIO_ERROR_MEDIA_CHANGED 5
+#define ATA_PIO_ERROR_UNCORRECTABLE_DATA 6
+#define ATA_PIO_ERROR_BAD_BLOCK 7
+
+#define ATA_PIO_STATUS_REG_ERR (1<<0)
+#define ATA_PIO_STATUS_IDX (1<<1)
+#define ATA_PIO_STATUS_CORP (1<<2)
+#define ATA_PIO_STATUS_DRQ (1<<3)
+#define ATA_PIO_STATUS_SRV (1<<4)
+#define ATA_PIO_STATUS_DRIVE_FAULT (1<<5)
+#define ATA_PIO_STATUS_DRIVE_RDY (1<<6)
+#define ATA_PIO_STATUS_DRIVE_BUSY (1<<7)
+
+#define ATA_DEV_PATA 1
+#define ATA_DEV_SATA 2
+#define ATA_DEV_PATAPI 3
+#define ATA_DEV_SATAPI 4
+#define ATA_DEV_UNKNOWN 0
+
+struct ata_drive {
+	int16_t base;
+	int16_t dev_ctl;
+	int status;
+	int isSlave;
+};
+
+
+int ATADectectType(struct ata_drive* drive);
+int ATAInit();