ata: add platform driver for Calxeda AHCI controller

Calxeda highbank SATA phy has intermittent problems bringing up a link
with Gen3 drives. Retrying the phy hard reset can work-around this issue,
but each reset also disables spread spectrum support. The reset function
also needs to reprogram the phy to enable spread spectrum support.

Create a new driver based on ahci_platform to support the Calxeda Highbank
SATA controller.

Signed-off-by: Mark Langsdorf <mark.langsdorf@calxeda.com>
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

1 files changed, 450 insertions, 0 deletions

diff --git a/drivers/ata/sata_highbank.c b/drivers/ata/sata_highbank.c
new file mode 100644
index 00000000000..0d7c4c2cd26
--- /dev/null
+++ b/drivers/ata/sata_highbank.c
@@ -0,0 +1,450 @@
+/*
+ * Calxeda Highbank AHCI SATA platform driver
+ * Copyright 2012 Calxeda, Inc.
+ *
+ * based on the AHCI SATA platform driver by Jeff Garzik and Anton Vorontsov
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <linux/kernel.h>
+#include <linux/gfp.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/spinlock.h>
+#include <linux/device.h>
+#include <linux/of_device.h>
+#include <linux/of_address.h>
+#include <linux/platform_device.h>
+#include <linux/libata.h>
+#include <linux/ahci_platform.h>
+#include <linux/interrupt.h>
+#include <linux/delay.h>
+#include <linux/export.h>
+#include "ahci.h"
+
+#define CPHY_MAP(dev, addr) ((((dev) & 0x1f) << 7) | (((addr) >> 9) & 0x7f))
+#define CPHY_ADDR(addr) (((addr) & 0x1ff) << 2)
+#define SERDES_CR_CTL			0x80a0
+#define SERDES_CR_ADDR			0x80a1
+#define SERDES_CR_DATA			0x80a2
+#define CR_BUSY				0x0001
+#define CR_START			0x0001
+#define CR_WR_RDN			0x0002
+#define CPHY_RX_INPUT_STS		0x2002
+#define CPHY_SATA_OVERRIDE	 	0x4000
+#define CPHY_OVERRIDE			0x2005
+#define SPHY_LANE			0x100
+#define SPHY_HALF_RATE			0x0001
+#define CPHY_SATA_DPLL_MODE		0x0700
+#define CPHY_SATA_DPLL_SHIFT		8
+#define CPHY_SATA_DPLL_RESET		(1 << 11)
+#define CPHY_PHY_COUNT			6
+#define CPHY_LANE_COUNT			4
+#define CPHY_PORT_COUNT			(CPHY_PHY_COUNT * CPHY_LANE_COUNT)
+
+static DEFINE_SPINLOCK(cphy_lock);
+/* Each of the 6 phys can have up to 4 sata ports attached to i. Map 0-based
+ * sata ports to their phys and then to their lanes within the phys
+ */
+struct phy_lane_info {
+	void __iomem *phy_base;
+	u8 lane_mapping;
+	u8 phy_devs;
+};
+static struct phy_lane_info port_data[CPHY_PORT_COUNT];
+
+static u32 __combo_phy_reg_read(u8 sata_port, u32 addr)
+{
+	u32 data;
+	u8 dev = port_data[sata_port].phy_devs;
+	spin_lock(&cphy_lock);
+	writel(CPHY_MAP(dev, addr), port_data[sata_port].phy_base + 0x800);
+	data = readl(port_data[sata_port].phy_base + CPHY_ADDR(addr));
+	spin_unlock(&cphy_lock);
+	return data;
+}
+
+static void __combo_phy_reg_write(u8 sata_port, u32 addr, u32 data)
+{
+	u8 dev = port_data[sata_port].phy_devs;
+	spin_lock(&cphy_lock);
+	writel(CPHY_MAP(dev, addr), port_data[sata_port].phy_base + 0x800);
+	writel(data, port_data[sata_port].phy_base + CPHY_ADDR(addr));
+	spin_unlock(&cphy_lock);
+}
+
+static void combo_phy_wait_for_ready(u8 sata_port)
+{
+	while (__combo_phy_reg_read(sata_port, SERDES_CR_CTL) & CR_BUSY)
+		udelay(5);
+}
+
+static u32 combo_phy_read(u8 sata_port, u32 addr)
+{
+	combo_phy_wait_for_ready(sata_port);
+	__combo_phy_reg_write(sata_port, SERDES_CR_ADDR, addr);
+	__combo_phy_reg_write(sata_port, SERDES_CR_CTL, CR_START);
+	combo_phy_wait_for_ready(sata_port);
+	return __combo_phy_reg_read(sata_port, SERDES_CR_DATA);
+}
+
+static void combo_phy_write(u8 sata_port, u32 addr, u32 data)
+{
+	combo_phy_wait_for_ready(sata_port);
+	__combo_phy_reg_write(sata_port, SERDES_CR_ADDR, addr);
+	__combo_phy_reg_write(sata_port, SERDES_CR_DATA, data);
+	__combo_phy_reg_write(sata_port, SERDES_CR_CTL, CR_WR_RDN | CR_START);
+}
+
+static void highbank_cphy_disable_overrides(u8 sata_port)
+{
+	u8 lane = port_data[sata_port].lane_mapping;
+	u32 tmp;
+	if (unlikely(port_data[sata_port].phy_base == NULL))
+		return;
+	tmp = combo_phy_read(sata_port, CPHY_RX_INPUT_STS + lane * SPHY_LANE);
+	tmp &= ~CPHY_SATA_OVERRIDE;
+	combo_phy_write(sata_port, CPHY_OVERRIDE + lane * SPHY_LANE, tmp);
+}
+
+static void cphy_override_rx_mode(u8 sata_port, u32 val)
+{
+	u8 lane = port_data[sata_port].lane_mapping;
+	u32 tmp;
+	tmp = combo_phy_read(sata_port, CPHY_RX_INPUT_STS + lane * SPHY_LANE);
+	tmp &= ~CPHY_SATA_OVERRIDE;
+	combo_phy_write(sata_port, CPHY_OVERRIDE + lane * SPHY_LANE, tmp);
+
+	tmp |= CPHY_SATA_OVERRIDE;
+	combo_phy_write(sata_port, CPHY_OVERRIDE + lane * SPHY_LANE, tmp);
+
+	tmp &= ~CPHY_SATA_DPLL_MODE;
+	tmp |= val << CPHY_SATA_DPLL_SHIFT;
+	combo_phy_write(sata_port, CPHY_OVERRIDE + lane * SPHY_LANE, tmp);
+
+	tmp |= CPHY_SATA_DPLL_RESET;
+	combo_phy_write(sata_port, CPHY_OVERRIDE + lane * SPHY_LANE, tmp);
+
+	tmp &= ~CPHY_SATA_DPLL_RESET;
+	combo_phy_write(sata_port, CPHY_OVERRIDE + lane * SPHY_LANE, tmp);
+
+	msleep(15);
+}
+
+static void highbank_cphy_override_lane(u8 sata_port)
+{
+	u8 lane = port_data[sata_port].lane_mapping;
+	u32 tmp, k = 0;
+
+	if (unlikely(port_data[sata_port].phy_base == NULL))
+		return;
+	do {
+		tmp = combo_phy_read(sata_port, CPHY_RX_INPUT_STS +
+						lane * SPHY_LANE);
+	} while ((tmp & SPHY_HALF_RATE) && (k++ < 1000));
+	cphy_override_rx_mode(sata_port, 3);
+}
+
+static int highbank_initialize_phys(struct device *dev, void __iomem *addr)
+{
+	struct device_node *sata_node = dev->of_node;
+	int phy_count = 0, phy, port = 0;
+	void __iomem *cphy_base[CPHY_PHY_COUNT];
+	struct device_node *phy_nodes[CPHY_PHY_COUNT];
+	memset(port_data, 0, sizeof(struct phy_lane_info) * CPHY_PORT_COUNT);
+	memset(phy_nodes, 0, sizeof(struct device_node*) * CPHY_PHY_COUNT);
+
+	do {
+		u32 tmp;
+		struct of_phandle_args phy_data;
+		if (of_parse_phandle_with_args(sata_node,
+				"calxeda,port-phys", "#phy-cells",
+				port, &phy_data))
+			break;
+		for (phy = 0; phy < phy_count; phy++) {
+			if (phy_nodes[phy] == phy_data.np)
+				break;
+		}
+		if (phy_nodes[phy] == NULL) {
+			phy_nodes[phy] = phy_data.np;
+			cphy_base[phy] = of_iomap(phy_nodes[phy], 0);
+			if (cphy_base[phy] == NULL) {
+				return 0;
+			}
+			phy_count += 1;
+		}
+		port_data[port].lane_mapping = phy_data.args[0];
+		of_property_read_u32(phy_nodes[phy], "phydev", &tmp);
+		port_data[port].phy_devs = tmp;
+		port_data[port].phy_base = cphy_base[phy];
+		of_node_put(phy_data.np);
+		port += 1;
+	} while (port < CPHY_PORT_COUNT);
+	return 0;
+}
+
+static int ahci_highbank_hardreset(struct ata_link *link, unsigned int *class,
+				unsigned long deadline)
+{
+	const unsigned long *timing = sata_ehc_deb_timing(&link->eh_context);
+	struct ata_port *ap = link->ap;
+	struct ahci_port_priv *pp = ap->private_data;
+	u8 *d2h_fis = pp->rx_fis + RX_FIS_D2H_REG;
+	struct ata_taskfile tf;
+	bool online;
+	u32 sstatus;
+	int rc;
+	int retry = 10;
+
+	ahci_stop_engine(ap);
+
+	/* clear D2H reception area to properly wait for D2H FIS */
+	ata_tf_init(link->device, &tf);
+	tf.command = 0x80;
+	ata_tf_to_fis(&tf, 0, 0, d2h_fis);
+
+	do {
+		highbank_cphy_disable_overrides(link->ap->port_no);
+		rc = sata_link_hardreset(link, timing, deadline, &online, NULL);
+		highbank_cphy_override_lane(link->ap->port_no);
+
+		/* If the status is 1, we are connected, but the link did not
+		 * come up. So retry resetting the link again.
+		 */
+		if (sata_scr_read(link, SCR_STATUS, &sstatus))
+			break;
+		if (!(sstatus & 0x3))
+			break;
+	} while (!online && retry--);
+
+	ahci_start_engine(ap);
+
+	if (online)
+		*class = ahci_dev_classify(ap);
+
+	return rc;
+}
+
+static struct ata_port_operations ahci_highbank_ops = {
+	.inherits		= &ahci_ops,
+	.hardreset		= ahci_highbank_hardreset,
+};
+
+static const struct ata_port_info ahci_highbank_port_info = {
+	.flags          = AHCI_FLAG_COMMON,
+	.pio_mask       = ATA_PIO4,
+	.udma_mask      = ATA_UDMA6,
+	.port_ops       = &ahci_highbank_ops,
+};
+
+static struct scsi_host_template ahci_highbank_platform_sht = {
+	AHCI_SHT("highbank-ahci"),
+};
+
+static const struct of_device_id ahci_of_match[] = {
+	{ .compatible = "calxeda,hb-ahci" },
+	{},
+};
+MODULE_DEVICE_TABLE(of, ahci_of_match);
+
+static int __init ahci_highbank_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct ahci_host_priv *hpriv;
+	struct ata_host *host;
+	struct resource *mem;
+	int irq;
+	int n_ports;
+	int i;
+	int rc;
+	struct ata_port_info pi = ahci_highbank_port_info;
+	const struct ata_port_info *ppi[] = { &pi, NULL };
+
+	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!mem) {
+		dev_err(dev, "no mmio space\n");
+		return -EINVAL;
+	}
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq <= 0) {
+		dev_err(dev, "no irq\n");
+		return -EINVAL;
+	}
+
+	hpriv = devm_kzalloc(dev, sizeof(*hpriv), GFP_KERNEL);
+	if (!hpriv) {
+		dev_err(dev, "can't alloc ahci_host_priv\n");
+		return -ENOMEM;
+	}
+
+	hpriv->flags |= (unsigned long)pi.private_data;
+
+	hpriv->mmio = devm_ioremap(dev, mem->start, resource_size(mem));
+	if (!hpriv->mmio) {
+		dev_err(dev, "can't map %pR\n", mem);
+		return -ENOMEM;
+	}
+
+	rc = highbank_initialize_phys(dev, hpriv->mmio);
+	if (rc)
+		return rc;
+
+
+	ahci_save_initial_config(dev, hpriv, 0, 0);
+
+	/* prepare host */
+	if (hpriv->cap & HOST_CAP_NCQ)
+		pi.flags |= ATA_FLAG_NCQ;
+
+	if (hpriv->cap & HOST_CAP_PMP)
+		pi.flags |= ATA_FLAG_PMP;
+
+	ahci_set_em_messages(hpriv, &pi);
+
+	/* CAP.NP sometimes indicate the index of the last enabled
+	 * port, at other times, that of the last possible port, so
+	 * determining the maximum port number requires looking at
+	 * both CAP.NP and port_map.
+	 */
+	n_ports = max(ahci_nr_ports(hpriv->cap), fls(hpriv->port_map));
+
+	host = ata_host_alloc_pinfo(dev, ppi, n_ports);
+	if (!host) {
+		rc = -ENOMEM;
+		goto err0;
+	}
+
+	host->private_data = hpriv;
+
+	if (!(hpriv->cap & HOST_CAP_SSS) || ahci_ignore_sss)
+		host->flags |= ATA_HOST_PARALLEL_SCAN;
+
+	if (pi.flags & ATA_FLAG_EM)
+		ahci_reset_em(host);
+
+	for (i = 0; i < host->n_ports; i++) {
+		struct ata_port *ap = host->ports[i];
+
+		ata_port_desc(ap, "mmio %pR", mem);
+		ata_port_desc(ap, "port 0x%x", 0x100 + ap->port_no * 0x80);
+
+		/* set enclosure management message type */
+		if (ap->flags & ATA_FLAG_EM)
+			ap->em_message_type = hpriv->em_msg_type;
+
+		/* disabled/not-implemented port */
+		if (!(hpriv->port_map & (1 << i)))
+			ap->ops = &ata_dummy_port_ops;
+	}
+
+	rc = ahci_reset_controller(host);
+	if (rc)
+		goto err0;
+
+	ahci_init_controller(host);
+	ahci_print_info(host, "platform");
+
+	rc = ata_host_activate(host, irq, ahci_interrupt, 0,
+					&ahci_highbank_platform_sht);
+	if (rc)
+		goto err0;
+
+	return 0;
+err0:
+	return rc;
+}
+
+static int __devexit ahci_highbank_remove(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct ata_host *host = dev_get_drvdata(dev);
+
+	ata_host_detach(host);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM
+static int ahci_highbank_suspend(struct device *dev)
+{
+	struct ata_host *host = dev_get_drvdata(dev);
+	struct ahci_host_priv *hpriv = host->private_data;
+	void __iomem *mmio = hpriv->mmio;
+	u32 ctl;
+	int rc;
+
+	if (hpriv->flags & AHCI_HFLAG_NO_SUSPEND) {
+		dev_err(dev, "firmware update required for suspend/resume\n");
+		return -EIO;
+	}
+
+	/*
+	 * AHCI spec rev1.1 section 8.3.3:
+	 * Software must disable interrupts prior to requesting a
+	 * transition of the HBA to D3 state.
+	 */
+	ctl = readl(mmio + HOST_CTL);
+	ctl &= ~HOST_IRQ_EN;
+	writel(ctl, mmio + HOST_CTL);
+	readl(mmio + HOST_CTL); /* flush */
+
+	rc = ata_host_suspend(host, PMSG_SUSPEND);
+	if (rc)
+		return rc;
+
+	return 0;
+}
+
+static int ahci_highbank_resume(struct device *dev)
+{
+	struct ata_host *host = dev_get_drvdata(dev);
+	int rc;
+
+	if (dev->power.power_state.event == PM_EVENT_SUSPEND) {
+		rc = ahci_reset_controller(host);
+		if (rc)
+			return rc;
+
+		ahci_init_controller(host);
+	}
+
+	ata_host_resume(host);
+
+	return 0;
+}
+#endif
+
+SIMPLE_DEV_PM_OPS(ahci_highbank_pm_ops,
+		  ahci_highbank_suspend, ahci_highbank_resume);
+
+static struct platform_driver ahci_highbank_driver = {
+        .remove = __devexit_p(ahci_highbank_remove),
+        .driver = {
+                .name = "highbank-ahci",
+                .owner = THIS_MODULE,
+                .of_match_table = ahci_of_match,
+                .pm = &ahci_highbank_pm_ops,
+        },
+	.probe = ahci_highbank_probe,
+};
+
+module_platform_driver(ahci_highbank_driver);
+
+MODULE_DESCRIPTION("Calxeda Highbank AHCI SATA platform driver");
+MODULE_AUTHOR("Mark Langsdorf <mark.langsdorf@calxeda.com>");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("sata:highbank");