Add LBA48 support to AHCI driver

* linux/dev/drivers/block/ahci.c (port): Extend `capacity' field type to
unsigned long long. Add `lba48' field. Make `identify' field unsigned.
(ahci_do_port_request): When `lba48' is true, use WIN_READDMA_EXT and
WIN_WRITEDMA_EXT commands.
(ahci_probe_port): Test lba48 flag, read capacity and set `lba48'
accordingly. Display size in GiB above 10GiB.
* linux/src/include/linux/hdreg.h (WIN_READDMA_EXT, WIN_WRITEDMA_EXT): New
macros
(hd_driveid): Add `command_set_2' and lba_capacity_2' fields.

2 files changed, 41 insertions, 12 deletions

diff --git a/linux/dev/drivers/block/ahci.c b/linux/dev/drivers/block/ahci.c
index 0ea1e3e8..3b31e846 100644
--- a/linux/dev/drivers/block/ahci.c
+++ b/linux/dev/drivers/block/ahci.c
@@ -239,13 +239,14 @@ static struct port {
 	struct ahci_fis *fis;
 	struct ahci_cmd_tbl *prdtl;
 
-	unsigned capacity;		/* Nr of sectors */
+	unsigned long long capacity;	/* Nr of sectors */
 	u32 status;			/* interrupt status */
 	unsigned cls;			/* Command list maximum size.
 					   We currently only use 1. */
 	struct wait_queue *q;		/* IRQ wait queue */
 	struct hd_struct *part;		/* drive partition table */
-	int identify;			/* Whether we are just identifying
+	unsigned lba48;			/* Whether LBA48 is supported */
+	unsigned identify;		/* Whether we are just identifying
 					   at boot */
 } ports[MAX_PORTS];
 
@@ -301,10 +302,16 @@ static void ahci_do_port_request(struct port *port, unsigned sector, struct requ
 	fis_h2d = (void*) &prdtl[slot].cfis;
 	fis_h2d->fis_type = FIS_TYPE_REG_H2D;
 	fis_h2d->flags = 128;
-	if (rq->cmd == READ)
-		fis_h2d->command = WIN_READDMA;
+	if (port->lba48)
+		if (rq->cmd == READ)
+			fis_h2d->command = WIN_READDMA_EXT;
+		else
+			fis_h2d->command = WIN_WRITEDMA_EXT;
 	else
-		fis_h2d->command = WIN_WRITEDMA;
+		if (rq->cmd == READ)
+			fis_h2d->command = WIN_READDMA;
+		else
+			fis_h2d->command = WIN_WRITEDMA;
 
 	fis_h2d->device = 1<<6;	/* LBA */
 
@@ -679,12 +686,35 @@ static void ahci_probe_port(const volatile struct ahci_host *ahci_host, const vo
 	{
 		printk("sd%u: identify error\n", port-ports);
 		port->capacity = 0;
+		port->lba48 = 0;
 	} else {
 		ide_fixstring(id.model,     sizeof(id.model),     1);
 		ide_fixstring(id.fw_rev,    sizeof(id.fw_rev),    1);
 		ide_fixstring(id.serial_no, sizeof(id.serial_no), 1);
-		port->capacity = id.lba_capacity;
-		printk("sd%u: %s, %uMB w/%dkB Cache\n", port - ports, id.model, port->capacity/2048, id.buf_size/2);
+		if (id.command_set_2 & (1U<<10))
+		{
+			port->lba48 = 1;
+			port->capacity = id.lba_capacity_2;
+			if (port->capacity >= (1ULL << 32))
+			{
+				port->capacity = (1ULL << 32) - 1;
+				printk("Warning: truncating disk size to 2TiB\n");
+			}
+		}
+		else
+		{
+			port->lba48 = 0;
+			port->capacity = id.lba_capacity;
+			if (port->capacity > (1ULL << 24))
+			{
+				port->capacity = (1ULL << 24);
+				printk("Warning: truncating disk size to 128GiB\n");
+			}
+		}
+		if (port->capacity/2048 >= 10240)
+			printk("sd%u: %s, %uGB w/%dkB Cache\n", port - ports, id.model, port->capacity/(2048*1024), id.buf_size/2);
+		else
+			printk("sd%u: %s, %uMB w/%dkB Cache\n", port - ports, id.model, port->capacity/2048, id.buf_size/2);
 	}
 	port->identify = 0;
 }
diff --git a/linux/src/include/linux/hdreg.h b/linux/src/include/linux/hdreg.h
index e223480d..4a388c5d 100644
--- a/linux/src/include/linux/hdreg.h
+++ b/linux/src/include/linux/hdreg.h
@@ -62,6 +62,8 @@
 #define WIN_SETFEATURES		0xEF	/* set special drive features */
 #define WIN_READDMA		0xc8	/* read sectors using DMA transfers */
 #define WIN_WRITEDMA		0xca	/* write sectors using DMA transfers */
+#define WIN_READDMA_EXT		0x25	/* read sectors using LBA48 DMA transfers */
+#define WIN_WRITEDMA_EXT	0x35	/* write sectors using LBA48 DMA transfers */
 
 /* Additional drive command codes used by ATAPI devices. */
 #define WIN_PIDENTIFY		0xA1	/* identify ATAPI device	*/
@@ -168,7 +170,7 @@ struct hd_driveid {
 	unsigned short  word80;
 	unsigned short  word81;
 	unsigned short  command_sets;	/* bits 0:Smart 1:Security 2:Removable 3:PM */
-	unsigned short  word83;		/* bits 14:Smart Enabled 13:0 zero */
+	unsigned short  command_set_2;	/* bits 14:Smart Enabled 13:0 zero */
 	unsigned short  word84;
 	unsigned short  word85;
 	unsigned short  word86;
@@ -185,10 +187,7 @@ struct hd_driveid {
 	unsigned short	word97;		/* reserved (word 97) */
 	unsigned short	word98;		/* reserved (word 98) */
 	unsigned short	word99;		/* reserved (word 99) */
-	unsigned short	word100;	/* reserved (word 100) */
-	unsigned short	word101;	/* reserved (word 101) */
-	unsigned short	word102;	/* reserved (word 102) */
-	unsigned short	word103;	/* reserved (word 103) */
+	unsigned long long lba_capacity_2; /* 48-bit total number of sectors */
 	unsigned short	word104;	/* reserved (word 104) */
 	unsigned short	word105;	/* reserved (word 105) */
 	unsigned short	word106;	/* reserved (word 106) */