From bc104fe5d949bd479437681772e763f56a9fc56f Mon Sep 17 00:00:00 2001
From: "K. Lange" <klange@toaruos.org>
Date: Wed, 27 Jun 2018 13:20:36 +0900
Subject: [PATCH] Read multiple sectors when loading ramdisk

---
 boot/atapi_imp.h     | 30 ++++++++++++++----------------
 boot/moremultiboot.h | 25 ++++++++++++++++---------
 2 files changed, 30 insertions(+), 25 deletions(-)

diff --git a/boot/atapi_imp.h b/boot/atapi_imp.h
index 88952db1..142cac10 100644
--- a/boot/atapi_imp.h
+++ b/boot/atapi_imp.h
@@ -156,9 +156,7 @@ static int ata_device_detect(struct ata_device * dev) {
 	return 0;
 }
 
-static int _read_12 = 0;
-
-static void ata_device_read_sector_atapi(struct ata_device * dev, uint32_t lba, uint8_t * buf) {
+static void ata_device_read_sectors_atapi(struct ata_device * dev, uint32_t lba, uint8_t * buf, int sectors) {
 
 	if (!dev->is_atapi) return;
 
@@ -182,16 +180,16 @@ _try_again:
 	}
 
 	atapi_command_t command;
-	command.command_bytes[0] = _read_12 ? 0xA8 : 0x28;
+	command.command_bytes[0] = 0x28;
 	command.command_bytes[1] = 0;
 	command.command_bytes[2] = (lba >> 0x18) & 0xFF;
 	command.command_bytes[3] = (lba >> 0x10) & 0xFF;
 	command.command_bytes[4] = (lba >> 0x08) & 0xFF;
 	command.command_bytes[5] = (lba >> 0x00) & 0xFF;
-	command.command_bytes[6] = 0;
-	command.command_bytes[7] = 0;
-	command.command_bytes[8] = _read_12 ? 0 : 1; /* bit 0 = PMI (0, last sector) */
-	command.command_bytes[9] = _read_12 ? 1 : 0; /* control */
+	command.command_bytes[6] = sectors >> 16;
+	command.command_bytes[7] = sectors >> 8;
+	command.command_bytes[8] = sectors; /* bit 0 = PMI (0, last sector) */
+	command.command_bytes[9] = 0; /* control */
 	command.command_bytes[10] = 0;
 	command.command_bytes[11] = 0;
 
@@ -199,22 +197,26 @@ _try_again:
 		outports(bus, command.command_words[i]);
 	}
 
+
+	for (int i = 0; i < sectors; ++i) {
 	while (1) {
 		uint8_t status = inportb(dev->io_base + ATA_REG_STATUS);
 		if ((status & ATA_SR_ERR)) goto atapi_error_on_read_setup_cmd;
 		if (!(status & ATA_SR_BSY) && (status & ATA_SR_DRQ)) break;
 	}
+		uint16_t size_to_read = inportb(bus + ATA_REG_LBA2) << 8;
+		size_to_read = size_to_read | inportb(bus + ATA_REG_LBA1);
 
-	uint16_t size_to_read = inportb(bus + ATA_REG_LBA2) << 8;
-	size_to_read = size_to_read | inportb(bus + ATA_REG_LBA1);
+		inportsm(bus,buf,size_to_read/2);
 
-	inportsm(bus,buf,size_to_read/2);
+		buf += 2048;
 
 	while (1) {
 		uint8_t status = inportb(dev->io_base + ATA_REG_STATUS);
 		if ((status & ATA_SR_ERR)) goto atapi_error_on_read_setup;
 		if (!(status & ATA_SR_BSY) && (status & ATA_SR_DRDY)) break;
 	}
+	}
 
 	return;
 
@@ -222,13 +224,9 @@ atapi_error_on_read_setup:
 	print("error on setup\n");
 	return;
 atapi_error_on_read_setup_cmd:
-	if (_read_12) {
-		_read_12 = 0;
-		print("trying again\n");
-		goto _try_again;
-	}
 	print("error on cmd\n");
 	return;
 }
 
 
+#define ata_device_read_sector_atapi(a,b,c) ata_device_read_sectors_atapi(a,b,c,1)
diff --git a/boot/moremultiboot.h b/boot/moremultiboot.h
index 5f9f7a58..62a37564 100644
--- a/boot/moremultiboot.h
+++ b/boot/moremultiboot.h
@@ -188,16 +188,23 @@ done:
 				modules_mboot[multiboot_header.mods_count-1].mod_start = ramdisk_off;
 				modules_mboot[multiboot_header.mods_count-1].mod_end = ramdisk_off + ramdisk_len;
 
-				print_("\n\n\n\n\n\n\n");
-				print_banner("Loading ramdisk...");
-				print_("\n\n\n");
-				attr = 0x70;
+				print_("Loading ramdisk");
 
-				for (int i = dir_entry->extent_start_LSB; i < dir_entry->extent_start_LSB + dir_entry->extent_length_LSB / 2048 + 1; ++i, offset += 2048) {
-					if (i % ((dir_entry->extent_length_LSB / 2048) / 80) == 0) {
-						print_(" ");
-					}
-					ata_device_read_sector_atapi(device, i, (uint8_t *)KERNEL_LOAD_START + offset);
+				int i = dir_entry->extent_start_LSB;
+				int sectors = dir_entry->extent_length_LSB / 2048 + 1;
+#define SECTORS 65536
+				while (sectors >= SECTORS) {
+					print_(".");
+					ata_device_read_sectors_atapi(device, i, (uint8_t *)KERNEL_LOAD_START + offset, SECTORS);
+
+					sectors -= SECTORS;
+					offset += 2048 * SECTORS;
+					i += SECTORS;
+				}
+				if (sectors > 0) {
+					print_("!");
+					ata_device_read_sectors_atapi(device, i, (uint8_t *)KERNEL_LOAD_START + offset, sectors);
+					offset += 2048;
 				}
 				attr = 0x07;
 				print("Done.\n");