diff --git a/drivers/ata/sata_promise.c b/drivers/ata/sata_promise.c
index 9c4389b5689a..8daf5d67dfe2 100644
--- a/drivers/ata/sata_promise.c
+++ b/drivers/ata/sata_promise.c
@@ -52,13 +52,13 @@
 enum {
 	PDC_PKT_SUBMIT		= 0x40, /* Command packet pointer addr */
 	PDC_INT_SEQMASK		= 0x40,	/* Mask of asserted SEQ INTs */
-	PDC_TBG_MODE		= 0x41C,	/* TBG mode */
 	PDC_FLASH_CTL		= 0x44, /* Flash control register */
 	PDC_GLOBAL_CTL		= 0x48, /* Global control/status (per port) */
 	PDC_CTLSTAT		= 0x60,	/* IDE control and status (per port) */
 	PDC_SATA_PLUG_CSR	= 0x6C, /* SATA Plug control/status reg */
 	PDC2_SATA_PLUG_CSR	= 0x60, /* SATAII Plug control/status reg */
-	PDC_SLEW_CTL		= 0x470, /* slew rate control reg */
+	PDC_TBG_MODE		= 0x41C, /* TBG mode (not SATAII) */
+	PDC_SLEW_CTL		= 0x470, /* slew rate control reg (not SATAII) */
 
 	PDC_ERR_MASK		= (1<<19) | (1<<20) | (1<<21) | (1<<22) |
 				  (1<<8) | (1<<9) | (1<<10),
@@ -77,6 +77,9 @@ enum {
 	PDC_COMMON_FLAGS	= ATA_FLAG_NO_LEGACY | ATA_FLAG_SRST |
 				  ATA_FLAG_MMIO | ATA_FLAG_NO_ATAPI |
 				  ATA_FLAG_PIO_POLLING,
+
+	/* hp->flags bits */
+	PDC_FLAG_GEN_II		= (1 << 0),
 };
 
 
@@ -86,6 +89,7 @@ struct pdc_port_priv {
 };
 
 struct pdc_host_priv {
+	unsigned long		flags;
 	int			hotplug_offset;
 };
 
@@ -234,20 +238,20 @@ static const struct ata_port_info pdc_port_info[] = {
 
 static const struct pci_device_id pdc_ata_pci_tbl[] = {
 	{ PCI_VDEVICE(PROMISE, 0x3371), board_2037x },
-	{ PCI_VDEVICE(PROMISE, 0x3570), board_2037x },
-	{ PCI_VDEVICE(PROMISE, 0x3571), board_2037x },
 	{ PCI_VDEVICE(PROMISE, 0x3373), board_2037x },
 	{ PCI_VDEVICE(PROMISE, 0x3375), board_2037x },
 	{ PCI_VDEVICE(PROMISE, 0x3376), board_2037x },
+	{ PCI_VDEVICE(PROMISE, 0x3570), board_2057x },
+	{ PCI_VDEVICE(PROMISE, 0x3571), board_2057x },
 	{ PCI_VDEVICE(PROMISE, 0x3574), board_2057x },
+	{ PCI_VDEVICE(PROMISE, 0x3d73), board_2057x },
 	{ PCI_VDEVICE(PROMISE, 0x3d75), board_2057x },
-	{ PCI_VDEVICE(PROMISE, 0x3d73), board_2037x },
 
 	{ PCI_VDEVICE(PROMISE, 0x3318), board_20319 },
 	{ PCI_VDEVICE(PROMISE, 0x3319), board_20319 },
 	{ PCI_VDEVICE(PROMISE, 0x3515), board_20319 },
 	{ PCI_VDEVICE(PROMISE, 0x3519), board_20319 },
-	{ PCI_VDEVICE(PROMISE, 0x3d17), board_20319 },
+	{ PCI_VDEVICE(PROMISE, 0x3d17), board_40518 },
 	{ PCI_VDEVICE(PROMISE, 0x3d18), board_40518 },
 
 	{ PCI_VDEVICE(PROMISE, 0x6629), board_20619 },
@@ -639,9 +643,11 @@ static void pdc_host_init(unsigned int chip_id, struct ata_probe_ent *pe)
 	 * "TODO: figure out why we do this"
 	 */
 
-	/* change FIFO_SHD to 8 dwords, enable BMR_BURST */
+	/* enable BMR_BURST, maybe change FIFO_SHD to 8 dwords */
 	tmp = readl(mmio + PDC_FLASH_CTL);
-	tmp |= 0x12000;	/* bit 16 (fifo 8 dw) and 13 (bmr burst?) */
+	tmp |= 0x02000;	/* bit 13 (enable bmr burst) */
+	if (!(hp->flags & PDC_FLAG_GEN_II))
+		tmp |= 0x10000;	/* bit 16 (fifo threshold at 8 dw) */
 	writel(tmp, mmio + PDC_FLASH_CTL);
 
 	/* clear plug/unplug flags for all ports */
@@ -652,6 +658,10 @@ static void pdc_host_init(unsigned int chip_id, struct ata_probe_ent *pe)
 	tmp = readl(mmio + hotplug_offset);
 	writel(tmp | 0xff0000, mmio + hotplug_offset);
 
+	/* don't initialise TBG or SLEW on 2nd generation chips */
+	if (hp->flags & PDC_FLAG_GEN_II)
+		return;
+
 	/* reduce TBG clock to 133 Mhz. */
 	tmp = readl(mmio + PDC_TBG_MODE);
 	tmp &= ~0x30000; /* clear bit 17, 16*/
@@ -745,6 +755,7 @@ static int pdc_ata_init_one (struct pci_dev *pdev, const struct pci_device_id *e
 	/* notice 4-port boards */
 	switch (board_idx) {
 	case board_40518:
+		hp->flags |= PDC_FLAG_GEN_II;
 		/* Override hotplug offset for SATAII150 */
 		hp->hotplug_offset = PDC2_SATA_PLUG_CSR;
 		/* Fall through */
@@ -758,15 +769,14 @@ static int pdc_ata_init_one (struct pci_dev *pdev, const struct pci_device_id *e
 		probe_ent->port[3].scr_addr = base + 0x700;
 		break;
 	case board_2057x:
+	case board_20771:
+		hp->flags |= PDC_FLAG_GEN_II;
 		/* Override hotplug offset for SATAII150 */
 		hp->hotplug_offset = PDC2_SATA_PLUG_CSR;
 		/* Fall through */
 	case board_2037x:
 		probe_ent->n_ports = 2;
 		break;
-	case board_20771:
-		probe_ent->n_ports = 2;
-		break;
 	case board_20619:
 		probe_ent->n_ports = 4;