ata_piix: only enable the first port on apple macbook pro

ICH8M on apple macbook pro occasionally locks up completely during PCS
initialization if ports other than the first one are enabled.  Add a
separate controller ID and only enable the first port.

tj: commit description added and patch updated to fit with the
    previous controller ID update.
Signed-off-by: Thomas Rohwer <tr@tng.de>
Signed-off-by: Tejun Heo <htejun@gmail.com>

drivers/ata/ata_piix.c

@@ -130,6 +130,7 @@ enum {
 	ich6m_sata_ahci,
 	ich8_sata_ahci,
 	ich8_2port_sata,
+	ich8m_apple_sata_ahci,		/* locks up on second port enable */
 	tolapai_sata_ahci,
 
 	/* constants for mapping table */
@@ -242,6 +243,8 @@ static const struct pci_device_id piix_pci_tbl[] = {
 	{ 0x8086, 0x2825, PCI_ANY_ID, PCI_ANY_ID, 0, 0, ich8_2port_sata },
 	/* Mobile SATA Controller IDE (ICH8M) */
 	{ 0x8086, 0x2828, PCI_ANY_ID, PCI_ANY_ID, 0, 0, ich8_sata_ahci },
+	/* Mobile SATA Controller IDE (ICH8M), Apple */
+	{ 0x8086, 0x2828, 0x106b, 0x00a0, 0, 0, ich8m_apple_sata_ahci },
 	/* SATA Controller IDE (ICH9) */
 	{ 0x8086, 0x2920, PCI_ANY_ID, PCI_ANY_ID, 0, 0, ich8_sata_ahci },
 	/* SATA Controller IDE (ICH9) */
@@ -449,6 +452,18 @@ static const struct piix_map_db ich8_2port_map_db = {
 	},
 };
 
+static const struct piix_map_db ich8m_apple_map_db = {
+	.mask = 0x3,
+	.port_enable = 0x1,
+	.map = {
+		/* PM   PS   SM   SS       MAP */
+		{  P0,  NA,  NA,  NA }, /* 00b */
+		{  RV,  RV,  RV,  RV },
+		{  P0,  P2, IDE, IDE }, /* 10b */
+		{  RV,  RV,  RV,  RV },
+	},
+};
+
 static const struct piix_map_db tolapai_map_db = {
 	.mask = 0x3,
 	.port_enable = 0x3,
@@ -468,6 +483,7 @@ static const struct piix_map_db *piix_map_db_table[] = {
 	[ich6m_sata_ahci]	= &ich6m_map_db,
 	[ich8_sata_ahci]	= &ich8_map_db,
 	[ich8_2port_sata]	= &ich8_2port_map_db,
+	[ich8m_apple_sata_ahci]	= &ich8m_apple_map_db,
 	[tolapai_sata_ahci]	= &tolapai_map_db,
 };
 
@@ -595,6 +611,18 @@ static struct ata_port_info piix_port_info[] = {
 		.udma_mask	= ATA_UDMA6,
 		.port_ops	= &piix_sata_ops,
 	},
+
+	[ich8m_apple_sata_ahci] =
+	{
+		.sht		= &piix_sht,
+		.flags		= PIIX_SATA_FLAGS | PIIX_FLAG_SCR |
+				  PIIX_FLAG_AHCI,
+		.pio_mask	= 0x1f,	/* pio0-4 */
+		.mwdma_mask	= 0x07, /* mwdma0-2 */
+		.udma_mask	= ATA_UDMA6,
+		.port_ops	= &piix_sata_ops,
+	},
+
 };
 
 static struct pci_bits piix_enable_bits[] = {