Device manager, panic and IDE read

8 files changed, 157 insertions, 20 deletions

diff --git a/src/loader/dev.c b/src/loader/dev.c
new file mode 100644
index 0000000..441aaed
--- /dev/null
+++ b/src/loader/dev.c
@@ -0,0 +1,50 @@
+// MIT License, Copyright (c) 2021 Marvin Borner
+// Device manager
+
+#include <dev.h>
+#include <lib.h>
+#include <pnc.h>
+
+static struct dev devices[32] = { 0 };
+
+static const char *dev_resolve_type(enum dev_type type)
+{
+	switch (type) {
+	case DEV_DISK:
+		return "Disk";
+	case DEV_FB:
+		return "Framebuffer";
+	default:
+		return "Unknown";
+	}
+}
+
+u32 dev_register(enum dev_type type, char *name, u32 data,
+		 s32 (*read)(void *, u32, u32, struct dev *),
+		 s32 (*write)(const void *, u32, u32, struct dev *))
+{
+	static u8 id = 0;
+
+	struct dev *dev = &devices[id];
+	dev->id = id;
+	dev->type = type;
+	dev->read = read;
+	dev->write = write;
+	dev->data = data;
+	dev->exists = 1;
+
+	assert(strlen(name) < sizeof(dev->name));
+	memcpy(dev->name, name, sizeof(dev->name));
+
+	return id++;
+}
+
+void dev_print(void)
+{
+	for (u8 i = 0; i < COUNT(devices); i++) {
+		struct dev *dev = &devices[i];
+		if (!dev->exists)
+			continue;
+		log("%d: %s device: %s\n", dev->id, dev_resolve_type(dev->type), dev->name);
+	}
+}
diff --git a/src/loader/ide.c b/src/loader/ide.c
index f279bc2..5cd67c7 100644
--- a/src/loader/ide.c
+++ b/src/loader/ide.c
@@ -2,8 +2,11 @@
 
 #include <cpu.h>
 #include <def.h>
+#include <dev.h>
 #include <ide.h>
+#include <lib.h>
 #include <log.h>
+#include <pnc.h>
 
 static u8 ide_buf[SECTOR_SIZE] = { 0 };
 
@@ -48,22 +51,67 @@ static u8 ide_find(u8 bus, u8 drive)
 			return 0;
 	} while ((status & ATA_SR_DRQ) == 0);
 
-	for (int i = 0; i < BLOCK_COUNT; i++)
+	for (u16 i = 0; i < BLOCK_COUNT; i++)
 		*(u16 *)(ide_buf + i * 2) = inw(io + ATA_REG_DATA);
 
 	return 1;
 }
 
+static void ide_delay(u16 io) // 400ns
+{
+	for (int i = 0; i < 4; i++)
+		inb(io + ATA_REG_ALTSTATUS);
+}
+
+static void ide_poll(u16 io)
+{
+	while (inb(io + ATA_REG_STATUS) & ATA_SR_BSY)
+		;
+
+	assert(!(inb(io + ATA_REG_STATUS) & ATA_SR_ERR));
+}
+
+static s32 ata_read(void *buf, u32 lba, u32 sector_count, struct dev *dev)
+{
+	u8 drive = dev->data & 0xff;
+	u16 io = (drive & ATA_PRIMARY << 1) == ATA_PRIMARY ? ATA_PRIMARY_IO : ATA_SECONDARY_IO;
+	drive = (drive & ATA_SLAVE) == ATA_SLAVE ? ATA_SLAVE : ATA_MASTER;
+	u8 cmd = drive == ATA_MASTER ? 0xe0 : 0xf0;
+
+	outb(io + ATA_REG_HDDEVSEL, (cmd | (u8)((lba >> 24 & 0x0f))));
+	outb(io + ATA_REG_FEATURES, 0);
+	outb(io + ATA_REG_SECCOUNT0, sector_count);
+	outb(io + ATA_REG_LBA0, (u8)lba);
+	outb(io + ATA_REG_LBA1, (u8)(lba >> 8));
+	outb(io + ATA_REG_LBA2, (u8)(lba >> 16));
+	outb(io + ATA_REG_COMMAND, ATA_CMD_READ_PIO);
+
+	u16 *b = buf;
+	u32 count = sector_count;
+	while (count-- > 0) {
+		ide_poll(io);
+		__asm__ volatile("rep insw" ::"c"(BLOCK_COUNT), "d"(io + ATA_REG_DATA),
+				 "D"((u32)b));
+	}
+
+	ide_delay(io);
+	return sector_count;
+}
+
 static void ata_probe(void)
 {
 	for (u8 i = 0; i < 4; i++) {
 		u32 bus = i < 2 ? ATA_PRIMARY : ATA_SECONDARY;
 		u32 drive = i % 2 ? ATA_MASTER : ATA_SLAVE;
+		u8 data = (bus << 1) | drive;
 
 		if (!ide_find(bus, drive))
 			continue;
 
-		log("[IDE] Found hd%c\n", 'a' + i);
+		char name[4] = { 0 };
+		strlcpy(name, "hd", sizeof(name));
+		name[2] = 'a' + i;
+		dev_register(DEV_DISK, name, data, ata_read, NULL);
 	}
 }
 
diff --git a/src/loader/inc/assert.h b/src/loader/inc/assert.h
deleted file mode 100644
index 65db119..0000000
--- a/src/loader/inc/assert.h
+++ /dev/null
@@ -1,17 +0,0 @@
-// MIT License, Copyright (c) 2021 Marvin Borner
-
-#ifndef ASSERT_H
-#define ASSERT_H
-
-#include <log.h>
-#define assert(exp)                                                                                \
-	{                                                                                          \
-		if (!(exp)) {                                                                      \
-			log("%s:%d: %s: Kernel assertion '%s' failed\n", __FILE__, __LINE__,       \
-			    __func__, #exp);                                                       \
-			while (1)                                                                  \
-				__asm__ volatile("cli\nhlt");                                      \
-		}                                                                                  \
-	}
-
-#endif
diff --git a/src/loader/inc/def.h b/src/loader/inc/def.h
index 8c2f9aa..cb41c78 100644
--- a/src/loader/inc/def.h
+++ b/src/loader/inc/def.h
@@ -22,6 +22,7 @@ typedef __builtin_va_list va_list;
 #define MIN(a, b) (((a) < (b)) ? (a) : (b))
 #define MAX(a, b) (((a) > (b)) ? (a) : (b))
 #define ABS(a) (((a) < 0) ? -(a) : (a))
+#define COUNT(a) (sizeof(a) / sizeof 0 [a])
 
 #define PACKED __attribute__((packed))
 
diff --git a/src/loader/inc/dev.h b/src/loader/inc/dev.h
new file mode 100644
index 0000000..930b35c
--- /dev/null
+++ b/src/loader/inc/dev.h
@@ -0,0 +1,30 @@
+// MIT License, Copyright (c) 2021 Marvin Borner
+
+#ifndef DEV_H
+#define DEV_H
+
+#include <def.h>
+
+enum dev_type {
+	DEV_DISK,
+	DEV_FB,
+};
+
+struct dev {
+	u8 id;
+	enum dev_type type;
+	char name[16];
+
+	s32 (*read)(void *, u32, u32, struct dev *);
+	s32 (*write)(const void *, u32, u32, struct dev *);
+
+	u32 data; // Optional (device-specific) data/information
+	u8 exists : 1;
+};
+
+u32 dev_register(enum dev_type type, char *name, u32 data,
+		 s32 (*read)(void *, u32, u32, struct dev *),
+		 s32 (*write)(const void *, u32, u32, struct dev *));
+void dev_print(void);
+
+#endif
diff --git a/src/loader/inc/pnc.h b/src/loader/inc/pnc.h
new file mode 100644
index 0000000..3de3364
--- /dev/null
+++ b/src/loader/inc/pnc.h
@@ -0,0 +1,21 @@
+// MIT License, Copyright (c) 2021 Marvin Borner
+
+#ifndef PNC_H
+#define PNC_H
+
+#include <log.h>
+
+#define panic(reason)                                                                              \
+	{                                                                                          \
+		log("%s:%d: %s: Panic: %s\n", __FILE__, __LINE__, __func__, (reason));             \
+		while (1)                                                                          \
+			__asm__ volatile("cli\nhlt");                                              \
+	}
+
+#define assert(exp)                                                                                \
+	{                                                                                          \
+		if (!(exp))                                                                        \
+			panic("Assertion '" #exp "' failed");                                      \
+	}
+
+#endif
diff --git a/src/loader/log.c b/src/loader/log.c
index 5d60f38..4312fcc 100644
--- a/src/loader/log.c
+++ b/src/loader/log.c
@@ -1,7 +1,7 @@
-#include <assert.h>
 #include <cpu.h>
 #include <lib.h>
 #include <log.h>
+#include <pnc.h>
 
 /**
  * Formatting
diff --git a/src/loader/main.c b/src/loader/main.c
index 53bf53e..6fedcba 100644
--- a/src/loader/main.c
+++ b/src/loader/main.c
@@ -1,12 +1,14 @@
 // MIT License, Copyright (c) 2021 Marvin Borner
 
 #include <def.h>
+#include <dev.h>
 #include <ide.h>
 #include <log.h>
 
 /**
  * Entry
  */
+#include <pnc.h>
 
 int start(void);
 int start(void)
@@ -18,6 +20,8 @@ int start(void)
 
 	ata_install();
 
+	dev_print();
+
 	while (1)
 		;
 	return 0;