# HG changeset patch
# User John Tsiombikas <nuclear@member.fsf.org>
# Date 1323361175 -7200
# Node ID 2f555c81ae6748f0d50bfebe8fc7a1b8fd05d47b
# Parent  a398bf73fe93d2ba9e8d6de8e1992294cc159b0c
starting the filesystem

diff -r a398bf73fe93 -r 2f555c81ae67 src/ata.c
--- a/src/ata.c	Thu Dec 08 13:34:47 2011 +0200
+++ b/src/ata.c	Thu Dec 08 18:19:35 2011 +0200
@@ -53,11 +53,13 @@
 };
 
 
+static int readwrite_pio(int devno, uint64_t sect, void *buf, void (*rwdata)(struct device*, void*));
 static int identify(struct device *dev, int iface, int id);
 static void select_dev(struct device *dev);
 static int wait_busy(struct device *dev);
 static int wait_drq(struct device *dev);
 static void read_data(struct device *dev, void *buf);
+static void write_data(struct device *dev, void *buf);
 static inline uint8_t read_reg8(struct device *dev, int reg);
 static inline uint16_t read_reg16(struct device *dev, int reg);
 static inline void write_reg8(struct device *dev, int reg, uint8_t val);
@@ -110,6 +112,16 @@
 
 int ata_read_pio(int devno, uint64_t sect, void *buf)
 {
+	return readwrite_pio(devno, sect, buf, read_data);
+}
+
+int ata_write_pio(int devno, uint64_t sect, void *buf)
+{
+	return readwrite_pio(devno, sect, buf, write_data);
+}
+
+static int readwrite_pio(int devno, uint64_t sect, void *buf, void (*rwdata)(struct device*, void*))
+{
 	int use_irq, cmd, st, res = -1;
 	uint32_t sect_low, sect_high;
 	struct device *dev = devices + devno;
@@ -171,8 +183,8 @@
 		goto end;
 	}
 
-	/* read the data and we're done */
-	read_data(dev, buf);
+	/* read/write the data and we're done */
+	rwdata(dev, buf);
 	res = 0;
 end:
 	if(use_irq) {
@@ -181,14 +193,6 @@
 	return res;
 }
 
-int ata_write_pio(int devno, uint64_t sect, void *buf)
-{
-	if(devices[devno].id == -1) {
-		return -1;
-	}
-	return -1;
-}
-
 static int identify(struct device *dev, int iface, int id)
 {
 	/* base address of the two ATA interfaces */
@@ -301,6 +305,20 @@
 	}
 }
 
+static void write_data(struct device *dev, void *buf)
+{
+	int i;
+	uint16_t *ptr = buf;
+
+	/* wait for the data request from the device */
+	wait_drq(dev);
+
+	/* ready to transfer */
+	for(i=0; i<256; i++) {
+		write_reg16(dev, REG_DATA, *ptr++);
+	}
+}
+
 static inline uint8_t read_reg8(struct device *dev, int reg)
 {
 	uint8_t val;
diff -r a398bf73fe93 -r 2f555c81ae67 src/fs.c
--- a/src/fs.c	Thu Dec 08 13:34:47 2011 +0200
+++ b/src/fs.c	Thu Dec 08 18:19:35 2011 +0200
@@ -1,25 +1,50 @@
 #include <stdio.h>
+#include <stdlib.h>
+#include <assert.h>
 #include "fs.h"
 #include "ata.h"
 #include "part.h"
 #include "panic.h"
 
-#define PART_TYPE	0xcc
+#define MAGIC	0xccf5ccf5
+#define BLKSZ	1024
 
-static int find_rootfs(int *dev, struct partition *part);
+typedef uint32_t blkid;
+
+struct superblock {
+	uint32_t magic;
+
+	blkid istart;
+	unsigned int icount;
+
+	blkid dstart;
+	unsigned int dcount;
+};
+
+struct filesys {
+	int dev;
+	struct partition part;
+
+	struct superblock *sb;
+};
+
+static int find_rootfs(struct filesys *fs);
 
 /* root device & partition */
-static int rdev;
-static struct partition rpart;
+static struct filesys root;
 
 void init_fs(void)
 {
-	if(find_rootfs(&rdev, &rpart) == -1) {
+	root.sb = malloc(512);
+	assert(root.sb);
+
+	if(find_rootfs(&root) == -1) {
 		panic("can't find root filesystem\n");
 	}
 }
 
-static int find_rootfs(int *dev, struct partition *part)
+#define PART_TYPE	0xcc
+static int find_rootfs(struct filesys *fs)
 {
 	int i, num_dev, partid;
 	struct partition *plist, *p;
@@ -31,11 +56,17 @@
 		partid = 0;
 		while(p) {
 			if(get_part_type(p) == PART_TYPE) {
-				/* found it! */
-				printf("using ata%dp%d\n", i, partid);
-				*dev = i;
-				*part = *p;
-				return 0;
+				/* found the correct partition, now read the superblock
+				 * and make sure it's got the correct magic id
+				 */
+				ata_read_pio(i, p->start_sect + 2, fs->sb);
+
+				if(fs->sb->magic == MAGIC) {
+					printf("found root ata%dp%d\n", i, partid);
+					fs->dev = i;
+					fs->part = *p;
+					return 0;
+				}
 			}
 			p = p->next;
 			partid++;
diff -r a398bf73fe93 -r 2f555c81ae67 src/fs.h
--- a/src/fs.h	Thu Dec 08 13:34:47 2011 +0200
+++ b/src/fs.h	Thu Dec 08 18:19:35 2011 +0200
@@ -3,4 +3,5 @@
 
 void init_fs(void);
 
+
 #endif	/* FS_H_ */