[PATCH 1/3] Add disk hotswap support to libata RESEND #2

[Lukasz Kosewski <lkosewsk@gmail.com>]

Patch 01:  add promise SATAII150 support to the sata_promise driver.

As described in the archives, this patch adds support for those
notorious SATAII150 controllers with their weird hotplug offset and
prepares us for hotplug goodness.

Jeff:  The reason that ATA_FLAG_SATA is commented out on pdc_2057x
controllers is to keep them consistent with the 2037x controllers in
libata + sata_promise support PATA ports (as seen in 2.6.13-rc3-mm1). 
I've implemented all your other suggestions.

Luke Kosewski

28.07.05  Luke Kosewski  <lkosewsk@nit.ca>

	* A patch to the sata_promise driver in libata for it to correctly mask
	  out hotplug interrupts on SATAII150 Tx4/Tx2 Plus controllers.
	* This is a resend of the original patch which in particular:
	  - does not split up the interrupt handling function, and instead uses
	    a pdc_host_priv structure to pass along the location of the hotplug
	    registers.
	  - does not use spin_lock_irqsave, but the less expensive spin_lock in
	    the interrupt handler.

Signed-off-by:  Luke Kosewski <lkosewsk@nit.ca>

--- linux/drivers/scsi/sata_promise.c.old	2005-07-26 15:52:51.000000000 -0700
+++ linux/drivers/scsi/sata_promise.c	2005-07-27 09:37:29.000000000 -0700
@@ -52,6 +52,7 @@ enum {
 	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_ERR_MASK		= (1<<19) | (1<<20) | (1<<21) | (1<<22) |
@@ -60,8 +61,10 @@ enum {
 	board_2037x		= 0,	/* FastTrak S150 TX2plus */
 	board_20319		= 1,	/* FastTrak S150 TX4 */
 	board_20619		= 2,	/* FastTrak TX4000 */
+	board_2057x		= 3,	/* SATAII150 Tx2plus */
+	board_40518		= 4,	/* SATAII150 Tx4 */
 
-	PDC_HAS_PATA		= (1 << 1), /* PDC20375 has PATA */
+	PDC_HAS_PATA		= (1 << 1), /* PDC20375/20575 has PATA */
 
 	PDC_RESET		= (1 << 11), /* HDMA reset */
 };
@@ -72,6 +75,10 @@ struct pdc_port_priv {
 	dma_addr_t		pkt_dma;
 };
 
+struct pdc_host_priv {
+	unsigned int		hotplug_offset;
+};
+
 static u32 pdc_sata_scr_read (struct ata_port *ap, unsigned int sc_reg);
 static void pdc_sata_scr_write (struct ata_port *ap, unsigned int sc_reg, u32 val);
 static int pdc_ata_init_one (struct pci_dev *pdev, const struct pci_device_id *ent);
@@ -161,6 +168,28 @@ static struct ata_port_info pdc_port_inf
 		.udma_mask	= 0x7f, /* udma0-6 ; FIXME */
 		.port_ops	= &pdc_ata_ops,
 	},
+
+	/* board_2057x */
+	{
+		.sht		= &pdc_ata_sht,
+		.host_flags	= /* ATA_FLAG_SATA | */ ATA_FLAG_NO_LEGACY |
+				  ATA_FLAG_SRST | ATA_FLAG_MMIO,
+		.pio_mask	= 0x1f, /* pio0-4 */
+		.mwdma_mask	= 0x07, /* mwdma0-2 */
+		.udma_mask	= 0x7f, /* udma0-6 ; FIXME */
+		.port_ops	= &pdc_ata_ops,
+	},
+
+	/* board_40518 */
+	{
+		.sht		= &pdc_ata_sht,
+		.host_flags	= ATA_FLAG_SATA | ATA_FLAG_NO_LEGACY |
+				  ATA_FLAG_SRST | ATA_FLAG_MMIO,
+		.pio_mask	= 0x1f, /* pio0-4 */
+		.mwdma_mask	= 0x07, /* mwdma0-2 */
+		.udma_mask	= 0x7f, /* udma0-6 ; FIXME */
+		.port_ops	= &pdc_ata_ops,
+	},
 };
 
 static struct pci_device_id pdc_ata_pci_tbl[] = {
@@ -175,16 +204,16 @@ static struct pci_device_id pdc_ata_pci_
 	{ PCI_VENDOR_ID_PROMISE, 0x3376, PCI_ANY_ID, PCI_ANY_ID, 0, 0,
 	  board_2037x },
 	{ PCI_VENDOR_ID_PROMISE, 0x3574, PCI_ANY_ID, PCI_ANY_ID, 0, 0,
-	  board_2037x },
+	  board_2057x },
 	{ PCI_VENDOR_ID_PROMISE, 0x3d75, PCI_ANY_ID, PCI_ANY_ID, 0, 0,
-	  board_2037x },
+	  board_2057x },
 
 	{ PCI_VENDOR_ID_PROMISE, 0x3318, PCI_ANY_ID, PCI_ANY_ID, 0, 0,
 	  board_20319 },
 	{ PCI_VENDOR_ID_PROMISE, 0x3319, PCI_ANY_ID, PCI_ANY_ID, 0, 0,
 	  board_20319 },
 	{ PCI_VENDOR_ID_PROMISE, 0x3d18, PCI_ANY_ID, PCI_ANY_ID, 0, 0,
-	  board_20319 },
+	  board_40518 },
 
 	{ PCI_VENDOR_ID_PROMISE, 0x6629, PCI_ANY_ID, PCI_ANY_ID, 0, 0,
 	  board_20619 },
@@ -436,10 +465,9 @@ static irqreturn_t pdc_interrupt (int ir
 {
 	struct ata_host_set *host_set = dev_instance;
 	struct ata_port *ap;
-	u32 mask = 0;
-	unsigned int i, tmp;
-	unsigned int handled = 0;
 	void *mmio_base;
+	u32 mask = 0;
+	unsigned int i, tmp, handled = 0;
 
 	VPRINTK("ENTER\n");
 
@@ -449,7 +477,7 @@ static irqreturn_t pdc_interrupt (int ir
 	}
 
 	mmio_base = host_set->mmio_base;
-
+	
 	/* reading should also clear interrupts */
 	mask = readl(mmio_base + PDC_INT_SEQMASK);
 
@@ -457,14 +485,15 @@ static irqreturn_t pdc_interrupt (int ir
 		VPRINTK("QUICK EXIT 2\n");
 		return IRQ_NONE;
 	}
+
+	spin_lock(&host_set->lock);
+
 	mask &= 0xffff;		/* only 16 tags possible */
 	if (!mask) {
 		VPRINTK("QUICK EXIT 3\n");
-		return IRQ_NONE;
+		goto done_irq;
 	}
 
-	spin_lock(&host_set->lock);
-
 	writel(mask, mmio_base + PDC_INT_SEQMASK);
 
 	for (i = 0; i < host_set->n_ports; i++) {
@@ -480,10 +509,10 @@ static irqreturn_t pdc_interrupt (int ir
 		}
 	}
 
-        spin_unlock(&host_set->lock);
-
 	VPRINTK("EXIT\n");
-
+       
+done_irq:
+	spin_unlock(&host_set->lock);
 	return IRQ_RETVAL(handled);
 }
 
@@ -561,6 +590,8 @@ static void pdc_ata_setup_port(struct at
 static void pdc_host_init(unsigned int chip_id, struct ata_probe_ent *pe)
 {
 	void *mmio = pe->mmio_base;
+	struct pdc_host_priv *hp = pe->private_data;
+	unsigned int hotplug_offset = hp->hotplug_offset;
 	u32 tmp;
 
 	/*
@@ -575,12 +606,12 @@ static void pdc_host_init(unsigned int c
 	writel(tmp, mmio + PDC_FLASH_CTL);
 
 	/* clear plug/unplug flags for all ports */
-	tmp = readl(mmio + PDC_SATA_PLUG_CSR);
-	writel(tmp | 0xff, mmio + PDC_SATA_PLUG_CSR);
+	tmp = readl(mmio + hotplug_offset);
+	writel(tmp | 0xff, mmio + hotplug_offset);
 
 	/* mask plug/unplug ints */
-	tmp = readl(mmio + PDC_SATA_PLUG_CSR);
-	writel(tmp | 0xff0000, mmio + PDC_SATA_PLUG_CSR);
+	tmp = readl(mmio + hotplug_offset);
+	writel(tmp | 0xff0000, mmio + hotplug_offset);
 
 	/* reduce TBG clock to 133 Mhz. */
 	tmp = readl(mmio + PDC_TBG_MODE);
@@ -602,6 +633,7 @@ static int pdc_ata_init_one (struct pci_
 {
 	static int printed_version;
 	struct ata_probe_ent *probe_ent = NULL;
+	struct pdc_host_priv *hp;
 	unsigned long base;
 	void *mmio_base;
 	unsigned int board_idx = (unsigned int) ent->driver_data;
@@ -651,6 +683,18 @@ static int pdc_ata_init_one (struct pci_
 	}
 	base = (unsigned long) mmio_base;
 
+	hp = kmalloc(sizeof(*hp), GFP_KERNEL);
+	if (hp == NULL)
+	{
+		rc = -ENOMEM;
+		goto err_out_free_ent;
+	}
+	memset(hp, 0, sizeof(*hp));
+
+	probe_ent->private_data = hp;
+	/* Set default hotplug offset */
+	hp->hotplug_offset = PDC_SATA_PLUG_CSR;
+
 	probe_ent->sht		= pdc_port_info[board_idx].sht;
 	probe_ent->host_flags	= pdc_port_info[board_idx].host_flags;
 	probe_ent->pio_mask	= pdc_port_info[board_idx].pio_mask;
@@ -673,6 +717,9 @@ static int pdc_ata_init_one (struct pci_
 	
 	/* notice 4-port boards */
 	switch (board_idx) {
+	case board_40518:
+		/* Override hotplug_offset for SATAII150 */
+		hp->hotplug_offset = PDC2_SATA_PLUG_CSR;
 	case board_20319:
        		probe_ent->n_ports = 4;
 
@@ -685,6 +732,9 @@ static int pdc_ata_init_one (struct pci_
 		probe_ent->port_flags[2] = ATA_FLAG_SATA;
 		probe_ent->port_flags[3] = ATA_FLAG_SATA;
 		break;
+	case board_2057x:
+		/* Override hotplug_offset for SATAII150 */
+		hp->hotplug_offset = PDC2_SATA_PLUG_CSR;
 	case board_2037x:
 		/* Some boards have also PATA port */
 		tmp = readb(mmio_base + PDC_FLASH_CTL+1);