[PATCH] AHCI SATA vendor update from VIA

[Jeff Garzik <jgarzik@pobox.com>]

I received this ahci.c patch from VIA, and pass it on for review, 
comment, and testing.

This patch won't go in as-is, because it does too much special casing. 
But until we get around to that, people with VIA controllers probably 
want this...

	Jeff


--- ahci.c.orig	2005-11-21 14:24:48.000000000 +0800
+++ ahci.c	2005-11-21 14:25:35.000000000 +0800
@@ -59,6 +59,7 @@
 	RX_FIS_D2H_REG		= 0x40,	/* offset of D2H Register FIS data */
 
 	board_ahci		= 0,
+	board_via_ahci		= 1,
 
 	/* global controller registers */
 	HOST_CAP		= 0x00, /* host capabilities */
@@ -126,6 +127,7 @@
 	PORT_CMD_LIST_ON	= (1 << 15), /* cmd list DMA engine running */
 	PORT_CMD_FIS_ON		= (1 << 14), /* FIS DMA engine running */
 	PORT_CMD_FIS_RX		= (1 << 4), /* Enable FIS receive DMA engine */
+	PORT_CMD_CLO		= (1 << 3), /* CLO */
 	PORT_CMD_POWER_ON	= (1 << 2), /* Power up device */
 	PORT_CMD_SPIN_UP	= (1 << 1), /* Spin up device */
 	PORT_CMD_START		= (1 << 0), /* Enable port DMA engine */
@@ -183,6 +185,14 @@
 static u8 ahci_check_err(struct ata_port *ap);
 static inline int ahci_host_intr(struct ata_port *ap, struct ata_queued_cmd *qc);
 
+static int via_ahci_qc_issue(struct ata_queued_cmd *qc);
+static void via_ahci_phy_reset(struct ata_port *ap);
+static void via_ahci_port_stop(struct ata_port *ap);
+static int via_ahci_softreset(struct ata_port *ap);
+static unsigned int via_ata_busy_sleep (struct ata_port *ap,
+				    unsigned long tmout_pat,
+			    	    unsigned long tmout);
+
 static Scsi_Host_Template ahci_sht = {
 	.module			= THIS_MODULE,
 	.name			= DRV_NAME,
@@ -231,6 +241,35 @@
 	.host_stop		= ahci_host_stop,
 };
 
+static struct ata_port_operations via_ahci_ops = {
+	.port_disable		= ata_port_disable,
+
+	.check_status		= ahci_check_status,
+	.check_altstatus	= ahci_check_status,
+	.check_err		= ahci_check_err,
+	.dev_select		= ata_noop_dev_select,
+
+	.tf_read		= ahci_tf_read,
+
+
+	.qc_prep		= ahci_qc_prep,
+
+	.eng_timeout		= ahci_eng_timeout,
+
+	.irq_handler		= ahci_interrupt,
+	.irq_clear		= ahci_irq_clear,
+
+	.scr_read		= ahci_scr_read,
+	.scr_write		= ahci_scr_write,
+
+	.port_start		= ahci_port_start,
+	.host_stop		= ahci_host_stop,
+
+	.phy_reset		= via_ahci_phy_reset,
+	.qc_issue		= via_ahci_qc_issue,
+	.port_stop		= via_ahci_port_stop,
+};
+
 static struct ata_port_info ahci_port_info[] = {
 	/* board_ahci */
 	{
@@ -242,6 +281,16 @@
 		.udma_mask	= 0x7f, /* udma0-6 ; FIXME */
 		.port_ops	= &ahci_ops,
 	},
+	/* board_via_ahci */
+	{
+		.sht		= &ahci_sht,
+		.host_flags	= ATA_FLAG_SATA | ATA_FLAG_NO_LEGACY |
+				  ATA_FLAG_SRST | ATA_FLAG_MMIO |
+				  ATA_FLAG_PIO_DMA,
+		.pio_mask	= 0x03, /* pio3-4 */
+		.udma_mask	= 0x7f, /* udma0-6 ; FIXME */
+		.port_ops	= &via_ahci_ops,
+	},
 };
 
 static struct pci_device_id ahci_pci_tbl[] = {
@@ -263,6 +312,8 @@
 	  board_ahci }, /* ESB2 */
 	{ PCI_VENDOR_ID_INTEL, 0x2683, PCI_ANY_ID, PCI_ANY_ID, 0, 0,
 	  board_ahci }, /* ESB2 */
+	{ PCI_VENDOR_ID_VIA, 0x3349, PCI_ANY_ID, PCI_ANY_ID, 0, 0,
+	  board_via_ahci }, /* VT8251*/
 	{ }	/* terminate list */
 };
 
@@ -1049,6 +1100,244 @@
 	return rc;
 }
 
+/* START: patch code for VIA VT8251 ahci controller */
+
+static int via_ahci_softreset(struct ata_port *ap)
+{
+	void __iomem *port_mmio = (void __iomem *) ap->ioaddr.cmd_addr;
+	struct ahci_port_priv *pp = ap->private_data;
+	u32 tmp,i;
+	u8 *fisbuf;
+
+	VPRINTK("ENTER\n");
+
+	writel(0x00000000, port_mmio + PORT_IRQ_MASK);  /*disable interrupt */
+	readl (port_mmio + PORT_IRQ_MASK);  /* flush */
+
+	/* prepare the software-reset commands */
+
+	/* prepare first command header */
+	memset(pp->cmd_slot, 0, 32);
+	pp->cmd_slot[0].opts = 0x00000505;
+	pp->cmd_slot[0].status = 0;
+	pp->cmd_slot[0].tbl_addr = cpu_to_le32(pp->cmd_tbl_dma & 0xffffffff);
+	pp->cmd_slot[0].tbl_addr_hi = cpu_to_le32((pp->cmd_tbl_dma >> 16) >> 16);
+
+	/* prepare CMDFIS struct */
+	fisbuf = pp->cmd_tbl;
+	memset(fisbuf, 0, 64);
+	fisbuf[0] = 0x27;
+	fisbuf[7] = 0xa0;
+	fisbuf[15] = 0x04;
+	
+	/* trigger the commands */
+	writel(0x1, port_mmio + PORT_CMD_ISSUE);
+	readl (port_mmio + PORT_CMD_ISSUE); /* flush */
+
+	udelay(20);
+    /* wait command complete */
+	for (i = 0; i < 2000; i++) {
+		tmp = readl(port_mmio + PORT_CMD_ISSUE);
+		if ((tmp & 1) == 0) break;
+		msleep(20);
+	}
+
+	if (i == 2000) {
+		printk(KERN_WARNING "TimeOut for Wait Command complete\n");
+		return 1;
+	}
+
+	/* prepare second command header */
+	pp->cmd_slot[0].opts = 0x00000005;
+	pp->cmd_slot[0].status = 0;
+	pp->cmd_slot[0].tbl_addr = cpu_to_le32(pp->cmd_tbl_dma & 0xffffffff);
+	pp->cmd_slot[0].tbl_addr_hi = cpu_to_le32((pp->cmd_tbl_dma >> 16) >> 16);
+
+	fisbuf = pp->cmd_tbl;
+	memset(fisbuf, 0, 64);
+	fisbuf[0] = 0x27;
+	fisbuf[7] = 0xa0;
+	fisbuf[15] = 0x00;
+
+	/* trigger the commands */
+	writel(0x1, port_mmio + PORT_CMD_ISSUE);
+	readl (port_mmio + PORT_CMD_ISSUE); /* flush */
+
+	udelay(20);
+    /* wait command complete */
+	for (i = 0; i < 2000; i++) {
+		tmp = readl(port_mmio + PORT_CMD_ISSUE);
+		if ((tmp & 1) == 0) break;
+		msleep(20);
+	}
+
+	if (i == 2000) {
+		printk(KERN_WARNING "TimeOut for Wait Command complete\n");
+		return 1;
+	}
+
+	// enable port interrupt
+	writel(0xffffffff, port_mmio + PORT_IRQ_MASK);
+	readl (port_mmio + PORT_IRQ_MASK);  /* flush */
+
+	return 0;
+}
+
+static unsigned int via_ata_busy_sleep (struct ata_port *ap,
+				    unsigned long tmout_pat,
+			    	    unsigned long tmout)
+{
+	unsigned long timer_start, timeout;
+	u8 status;
+
+	status = ata_busy_wait(ap, ATA_BUSY, 300);
+	timer_start = jiffies;
+	timeout = timer_start + tmout_pat;
+	while ((status & ATA_BUSY) && (time_before(jiffies, timeout))) {
+		msleep(50);
+		status = ata_busy_wait(ap, ATA_BUSY, 3);
+	}
+
+	if (status & ATA_BUSY)
+		printk(KERN_WARNING "ata%u is slow to respond, "
+		       "please be patient\n", ap->id);
+
+	timeout = timer_start + tmout;
+	while ((status & ATA_BUSY) && (time_before(jiffies, timeout))) {
+		msleep(50);
+		status = ata_chk_status(ap);
+	}
+
+	if (status & ATA_BUSY) {
+		printk(KERN_ERR "ata%u failed to respond (%lu secs)\n",
+		       ap->id, tmout / HZ);
+		return 1;
+	}
+
+	return 0;
+}
+
+static void via_ahci_phy_reset(struct ata_port *ap)
+{
+	void __iomem *port_mmio = (void __iomem *) ap->ioaddr.cmd_addr;
+	struct ata_taskfile tf;
+	struct ata_device *dev = &ap->device[0];
+	u32 tmp;
+
+	u32 sstatus,i;
+	unsigned long timeout = jiffies + (HZ * 5);
+	u8 tmp_status;
+	
+	if (ap->flags & ATA_FLAG_SATA_RESET) {
+		/* issue phy wake/reset */
+		scr_write_flush(ap, SCR_CONTROL, 0x301);
+		udelay(400);			/* FIXME: a guess */
+	}
+	scr_write_flush(ap, SCR_CONTROL, 0x300); /* phy wake/clear reset */
+
+	/* wait for phy to become ready, if necessary */
+	do {
+		msleep(200);
+		sstatus = scr_read(ap, SCR_STATUS);
+		if ((sstatus & 0xf) != 1)
+			break;
+	} while (time_before(jiffies, timeout));
+
+	/* TODO: phy layer with polling, timeouts, etc. */
+	if (sata_dev_present(ap))
+		ata_port_probe(ap);
+	else {
+		sstatus = scr_read(ap, SCR_STATUS);
+		printk(KERN_INFO "ata%u: no device found (phy stat %08x)\n",
+		       ap->id, sstatus);
+		ata_port_disable(ap);
+	}
+
+	if (ap->flags & ATA_FLAG_PORT_DISABLED)
+		return;
+
+	/*Fix the VIA busy bug by a software reset*/
+	for (i = 0; i < 100; i++) {
+		tmp_status = ap->ops->check_status(ap);
+		if ((tmp_status & ATA_BUSY) == 0) break;
+		msleep(10);
+	}
+
+	if ((tmp_status & ATA_BUSY)) {
+		DPRINTK("Busy after CommReset, do softreset...\n"); 
+		/*set the PxCMD.CLO bit to clear BUSY and DRQ, to make the reset command sent out*/
+		tmp = readl(port_mmio + PORT_CMD);
+		tmp |= PORT_CMD_CLO;
+		writel(tmp, port_mmio + PORT_CMD);
+		readl(port_mmio + PORT_CMD); /* flush */
+
+		if (via_ahci_softreset(ap)) {
+			printk(KERN_WARNING "softreset failed\n");
+			return;
+		}
+	}
+
+	if (via_ata_busy_sleep(ap, ATA_TMOUT_BOOT_QUICK, ATA_TMOUT_BOOT)) {
+		ata_port_disable(ap);
+		return;
+	}
+
+	ap->cbl = ATA_CBL_SATA;
+
+	if (ap->flags & ATA_FLAG_PORT_DISABLED)
+		return;
+
+	tmp = readl(port_mmio + PORT_SIG);
+	tf.lbah		= (tmp >> 24)	& 0xff;
+	tf.lbam		= (tmp >> 16)	& 0xff;
+	tf.lbal		= (tmp >> 8)	& 0xff;
+	tf.nsect	= (tmp)		& 0xff;
+
+	dev->class = ata_dev_classify(&tf);
+	if (!ata_dev_present(dev))
+		ata_port_disable(ap);
+
+}
+
+static int via_ahci_qc_issue(struct ata_queued_cmd *qc)
+{
+	struct ata_port *ap = qc->ap;
+	void *port_mmio = (void *) ap->ioaddr.cmd_addr;
+
+    if (qc &&
+        qc->tf.command == ATA_CMD_SET_FEATURES &&
+        qc->tf.feature == SETFEATURES_XFER) {
+        /* skip set xfer mode process */
+
+		ata_qc_complete(qc, 0);
+		qc = NULL;
+        return 0;
+    }
+
+	writel(1, port_mmio + PORT_CMD_ISSUE);
+	readl(port_mmio + PORT_CMD_ISSUE);	/* flush */
+
+	return 0;
+}
+
+static void via_ahci_port_stop(struct ata_port *ap)
+{
+	struct device *dev = ap->host_set->dev;
+	struct ahci_port_priv *pp = ap->private_data;
+
+	/* spec says 500 msecs for each PORT_CMD_{START,FIS_RX} bit, so
+	 * this is slightly incorrect.
+	 */
+	msleep(500);
+
+	ap->private_data = NULL;
+	dma_free_coherent(dev, AHCI_PORT_PRIV_DMA_SZ,
+			  pp->cmd_slot, pp->cmd_slot_dma);
+	kfree(pp);
+	ata_port_stop(ap);
+}
+
+/* END: patch code for VIA VT8251 ahci controller */
 
 static int __init ahci_init(void)
 {