[PATCH v2] ata: ide-sff: add LBA48 support

[Antony Pavlov]

See http://wiki.osdev.org/ATA_PIO_Mode#48_bit_PIO for details.

Signed-off-by: Antony Pavlov <antonynpavlov at gmail.com>
---

Changes since v1:

  * fix typo in the commit message;
  * trivial change: put "port->lba48 = ata_id_has_lba48(port->id);"
    just after debug stuff (ata_dump_id(port->id)).

---
 drivers/ata/disk_ata_drive.c |  3 +++
 drivers/ata/ide-sff.c        | 54 +++++++++++++++++++++++++++++++++++---------
 include/ata_drive.h          |  3 +++
 3 files changed, 49 insertions(+), 11 deletions(-)

diff --git a/drivers/ata/disk_ata_drive.c b/drivers/ata/disk_ata_drive.c
index 1aa1bb145..5ebddbdec 100644
--- a/drivers/ata/disk_ata_drive.c
+++ b/drivers/ata/disk_ata_drive.c
@@ -237,6 +237,9 @@ static int ata_port_init(struct ata_port *port)
 #ifdef DEBUG
 	ata_dump_id(port->id);
 #endif
+
+	port->lba48 = ata_id_has_lba48(port->id);
+
 	if (port->devname) {
 		port->blk.cdev.name = xstrdup(port->devname);
 	} else {
diff --git a/drivers/ata/ide-sff.c b/drivers/ata/ide-sff.c
index 6dc89d79a..b7c884726 100644
--- a/drivers/ata/ide-sff.c
+++ b/drivers/ata/ide-sff.c
@@ -136,17 +136,33 @@ static int ata_wait_ready(struct ide_port *ide, unsigned timeout)
  * @param io Register file
  * @param drive 0 master drive, 1 slave drive
  * @param num Sector number
- *
- * @todo LBA48 support
  */
-static int ata_set_lba_sector(struct ide_port *ide, unsigned drive, uint64_t num)
+static int ata_set_lba_sector(struct ata_port *port, unsigned drive,
+				uint64_t num)
 {
-	if (num > 0x0FFFFFFF || drive > 1)
+	struct ide_port *ide = to_ata_drive_access(port);
+
+	if (drive > 1)
 		return -EINVAL;
 
-	ata_wr_byte(ide, 0xA0 | LBA_FLAG | drive << 4 | num >> 24,
-		    ide->io.device_addr);
-	ata_wr_byte(ide, 0x00, ide->io.error_addr);
+	if (port->lba48) {
+		if (num > (1ULL << 48) - 1)
+			return -EINVAL;
+
+		ata_wr_byte(ide, LBA_FLAG | drive << 4, ide->io.device_addr);
+
+		ata_wr_byte(ide, 0x00, ide->io.nsect_addr);
+		ata_wr_byte(ide, num >> 24, ide->io.lbal_addr);
+		ata_wr_byte(ide, num >> 32, ide->io.lbam_addr);
+		ata_wr_byte(ide, num >> 40, ide->io.lbah_addr);
+	} else {
+		if (num > (1ULL << 28) - 1)
+			return -EINVAL;
+
+		ata_wr_byte(ide, 0xA0 | LBA_FLAG | drive << 4 | num >> 24,
+			    ide->io.device_addr);
+	}
+
 	ata_wr_byte(ide, 0x01, ide->io.nsect_addr);
 	ata_wr_byte(ide, num, ide->io.lbal_addr);	/* 0 ... 7 */
 	ata_wr_byte(ide, num >> 8, ide->io.lbam_addr); /* 8 ... 15 */
@@ -316,10 +332,18 @@ static int ide_read(struct ata_port *port, void *buffer, unsigned int block,
 	struct ide_port *ide = to_ata_drive_access(port);
 
 	while (num_blocks) {
-		rc = ata_set_lba_sector(ide, DISK_MASTER, sector);
+		uint8_t cmd;
+
+		rc = ata_set_lba_sector(port, DISK_MASTER, sector);
 		if (rc != 0)
 			return rc;
-		rc = ata_wr_cmd(ide, ATA_CMD_READ);
+
+		if (port->lba48)
+			cmd = ATA_CMD_PIO_READ_EXT;
+		else
+			cmd = ATA_CMD_READ;
+
+		rc = ata_wr_cmd(ide, cmd);
 		if (rc != 0)
 			return rc;
 		rc = ata_wait_ready(ide, MAX_TIMEOUT);
@@ -355,10 +379,18 @@ static int __maybe_unused ide_write(struct ata_port *port,
 	struct ide_port *ide = to_ata_drive_access(port);
 
 	while (num_blocks) {
-		rc = ata_set_lba_sector(ide, DISK_MASTER, sector);
+		uint8_t cmd;
+
+		rc = ata_set_lba_sector(port, DISK_MASTER, sector);
 		if (rc != 0)
 			return rc;
-		rc = ata_wr_cmd(ide, ATA_CMD_WRITE);
+
+		if (port->lba48)
+			cmd = ATA_CMD_PIO_WRITE_EXT;
+		else
+			cmd = ATA_CMD_WRITE;
+
+		rc = ata_wr_cmd(ide, cmd);
 		if (rc != 0)
 			return rc;
 		rc = ata_wait_ready(ide, MAX_TIMEOUT);
diff --git a/include/ata_drive.h b/include/ata_drive.h
index 44073cb1b..11685eef1 100644
--- a/include/ata_drive.h
+++ b/include/ata_drive.h
@@ -37,8 +37,10 @@
 
 #define ATA_CMD_ID_ATA		0xEC
 #define ATA_CMD_READ		0x20
+#define ATA_CMD_PIO_READ_EXT	0x24
 #define ATA_CMD_READ_EXT	0x25
 #define ATA_CMD_WRITE		0x30
+#define ATA_CMD_PIO_WRITE_EXT	0x34
 #define ATA_CMD_WRITE_EXT	0x35
 
 /* drive's status flags */
@@ -140,6 +142,7 @@ struct ata_port {
 	void *drvdata;
 	struct block_device blk;
 	uint16_t *id;
+	int lba48;
 	int initialized;
 	int probe;
 };
-- 
2.11.0