1 files changed, 452 insertions, 0 deletions
diff --git a/drivers/net/ethernet/qualcomm/emac/emac-sgmii.c b/drivers/net/ethernet/qualcomm/emac/emac-sgmii.c
new file mode 100644
index 000000000..c694e3428
--- /dev/null
+++ b/drivers/net/ethernet/qualcomm/emac/emac-sgmii.c
@@ -0,0 +1,452 @@
+/* Copyright (c) 2015-2016, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that 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.
+ */
+
+/* Qualcomm Technologies, Inc. EMAC SGMII Controller driver.
+ */
+
+#include <linux/interrupt.h>
+#include <linux/iopoll.h>
+#include <linux/acpi.h>
+#include <linux/of_device.h>
+#include "emac.h"
+#include "emac-mac.h"
+#include "emac-sgmii.h"
+
+/* EMAC_SGMII register offsets */
+#define EMAC_SGMII_PHY_AUTONEG_CFG2		0x0048
+#define EMAC_SGMII_PHY_SPEED_CFG1		0x0074
+#define EMAC_SGMII_PHY_IRQ_CMD			0x00ac
+#define EMAC_SGMII_PHY_INTERRUPT_CLEAR		0x00b0
+#define EMAC_SGMII_PHY_INTERRUPT_MASK		0x00b4
+#define EMAC_SGMII_PHY_INTERRUPT_STATUS		0x00b8
+#define EMAC_SGMII_PHY_RX_CHK_STATUS		0x00d4
+
+#define FORCE_AN_TX_CFG				BIT(5)
+#define FORCE_AN_RX_CFG				BIT(4)
+#define AN_ENABLE				BIT(0)
+
+#define DUPLEX_MODE				BIT(4)
+#define SPDMODE_1000				BIT(1)
+#define SPDMODE_100				BIT(0)
+#define SPDMODE_10				0
+
+#define CDR_ALIGN_DET				BIT(6)
+
+#define IRQ_GLOBAL_CLEAR			BIT(0)
+
+#define DECODE_CODE_ERR				BIT(7)
+#define DECODE_DISP_ERR				BIT(6)
+
+#define SGMII_PHY_IRQ_CLR_WAIT_TIME		10
+
+#define SGMII_PHY_INTERRUPT_ERR		(DECODE_CODE_ERR | DECODE_DISP_ERR)
+#define SGMII_ISR_MASK  		(SGMII_PHY_INTERRUPT_ERR)
+
+#define SERDES_START_WAIT_TIMES			100
+
+int emac_sgmii_init(struct emac_adapter *adpt)
+{
+	if (!(adpt->phy.sgmii_ops && adpt->phy.sgmii_ops->init))
+		return 0;
+
+	return adpt->phy.sgmii_ops->init(adpt);
+}
+
+int emac_sgmii_open(struct emac_adapter *adpt)
+{
+	if (!(adpt->phy.sgmii_ops && adpt->phy.sgmii_ops->open))
+		return 0;
+
+	return adpt->phy.sgmii_ops->open(adpt);
+}
+
+void emac_sgmii_close(struct emac_adapter *adpt)
+{
+	if (!(adpt->phy.sgmii_ops && adpt->phy.sgmii_ops->close))
+		return;
+
+	adpt->phy.sgmii_ops->close(adpt);
+}
+
+int emac_sgmii_link_change(struct emac_adapter *adpt, bool link_state)
+{
+	if (!(adpt->phy.sgmii_ops && adpt->phy.sgmii_ops->link_change))
+		return 0;
+
+	return adpt->phy.sgmii_ops->link_change(adpt, link_state);
+}
+
+void emac_sgmii_reset(struct emac_adapter *adpt)
+{
+	if (!(adpt->phy.sgmii_ops && adpt->phy.sgmii_ops->reset))
+		return;
+
+	adpt->phy.sgmii_ops->reset(adpt);
+}
+
+/* Initialize the SGMII link between the internal and external PHYs. */
+static void emac_sgmii_link_init(struct emac_adapter *adpt)
+{
+	struct emac_sgmii *phy = &adpt->phy;
+	u32 val;
+
+	/* Always use autonegotiation. It works no matter how the external
+	 * PHY is configured.
+	 */
+	val = readl(phy->base + EMAC_SGMII_PHY_AUTONEG_CFG2);
+	val &= ~(FORCE_AN_RX_CFG | FORCE_AN_TX_CFG);
+	val |= AN_ENABLE;
+	writel(val, phy->base + EMAC_SGMII_PHY_AUTONEG_CFG2);
+}
+
+static int emac_sgmii_irq_clear(struct emac_adapter *adpt, u8 irq_bits)
+{
+	struct emac_sgmii *phy = &adpt->phy;
+	u8 status;
+
+	writel_relaxed(irq_bits, phy->base + EMAC_SGMII_PHY_INTERRUPT_CLEAR);
+	writel_relaxed(IRQ_GLOBAL_CLEAR, phy->base + EMAC_SGMII_PHY_IRQ_CMD);
+	/* Ensure interrupt clear command is written to HW */
+	wmb();
+
+	/* After set the IRQ_GLOBAL_CLEAR bit, the status clearing must
+	 * be confirmed before clearing the bits in other registers.
+	 * It takes a few cycles for hw to clear the interrupt status.
+	 */
+	if (readl_poll_timeout_atomic(phy->base +
+				      EMAC_SGMII_PHY_INTERRUPT_STATUS,
+				      status, !(status & irq_bits), 1,
+				      SGMII_PHY_IRQ_CLR_WAIT_TIME)) {
+		net_err_ratelimited("%s: failed to clear SGMII irq: status:0x%x bits:0x%x\n",
+				    adpt->netdev->name, status, irq_bits);
+		return -EIO;
+	}
+
+	/* Finalize clearing procedure */
+	writel_relaxed(0, phy->base + EMAC_SGMII_PHY_IRQ_CMD);
+	writel_relaxed(0, phy->base + EMAC_SGMII_PHY_INTERRUPT_CLEAR);
+
+	/* Ensure that clearing procedure finalization is written to HW */
+	wmb();
+
+	return 0;
+}
+
+/* The number of decode errors that triggers a reset */
+#define DECODE_ERROR_LIMIT	2
+
+static irqreturn_t emac_sgmii_interrupt(int irq, void *data)
+{
+	struct emac_adapter *adpt = data;
+	struct emac_sgmii *phy = &adpt->phy;
+	u8 status;
+
+	status = readl(phy->base + EMAC_SGMII_PHY_INTERRUPT_STATUS);
+	status &= SGMII_ISR_MASK;
+	if (!status)
+		return IRQ_HANDLED;
+
+	/* If we get a decoding error and CDR is not locked, then try
+	 * resetting the internal PHY.  The internal PHY uses an embedded
+	 * clock with Clock and Data Recovery (CDR) to recover the
+	 * clock and data.
+	 */
+	if (status & SGMII_PHY_INTERRUPT_ERR) {
+		int count;
+
+		/* The SGMII is capable of recovering from some decode
+		 * errors automatically.  However, if we get multiple
+		 * decode errors in a row, then assume that something
+		 * is wrong and reset the interface.
+		 */
+		count = atomic_inc_return(&phy->decode_error_count);
+		if (count == DECODE_ERROR_LIMIT) {
+			schedule_work(&adpt->work_thread);
+			atomic_set(&phy->decode_error_count, 0);
+		}
+	} else {
+		/* We only care about consecutive decode errors. */
+		atomic_set(&phy->decode_error_count, 0);
+	}
+
+	if (emac_sgmii_irq_clear(adpt, status))
+		schedule_work(&adpt->work_thread);
+
+	return IRQ_HANDLED;
+}
+
+static void emac_sgmii_reset_prepare(struct emac_adapter *adpt)
+{
+	struct emac_sgmii *phy = &adpt->phy;
+	u32 val;
+
+	/* Reset PHY */
+	val = readl(phy->base + EMAC_EMAC_WRAPPER_CSR2);
+	writel(((val & ~PHY_RESET) | PHY_RESET), phy->base +
+	       EMAC_EMAC_WRAPPER_CSR2);
+	/* Ensure phy-reset command is written to HW before the release cmd */
+	msleep(50);
+	val = readl(phy->base + EMAC_EMAC_WRAPPER_CSR2);
+	writel((val & ~PHY_RESET), phy->base + EMAC_EMAC_WRAPPER_CSR2);
+	/* Ensure phy-reset release command is written to HW before initializing
+	 * SGMII
+	 */
+	msleep(50);
+}
+
+static void emac_sgmii_common_reset(struct emac_adapter *adpt)
+{
+	int ret;
+
+	emac_sgmii_reset_prepare(adpt);
+	emac_sgmii_link_init(adpt);
+
+	ret = emac_sgmii_init(adpt);
+	if (ret)
+		netdev_err(adpt->netdev,
+			   "could not reinitialize internal PHY (error=%i)\n",
+			   ret);
+}
+
+static int emac_sgmii_common_open(struct emac_adapter *adpt)
+{
+	struct emac_sgmii *sgmii = &adpt->phy;
+	int ret;
+
+	if (sgmii->irq) {
+		/* Make sure interrupts are cleared and disabled first */
+		ret = emac_sgmii_irq_clear(adpt, 0xff);
+		if (ret)
+			return ret;
+		writel(0, sgmii->base + EMAC_SGMII_PHY_INTERRUPT_MASK);
+
+		ret = request_irq(sgmii->irq, emac_sgmii_interrupt, 0,
+				  "emac-sgmii", adpt);
+		if (ret) {
+			netdev_err(adpt->netdev,
+				   "could not register handler for internal PHY\n");
+			return ret;
+		}
+	}
+
+	return 0;
+}
+
+static void emac_sgmii_common_close(struct emac_adapter *adpt)
+{
+	struct emac_sgmii *sgmii = &adpt->phy;
+
+	/* Make sure interrupts are disabled */
+	writel(0, sgmii->base + EMAC_SGMII_PHY_INTERRUPT_MASK);
+	free_irq(sgmii->irq, adpt);
+}
+
+/* The error interrupts are only valid after the link is up */
+static int emac_sgmii_common_link_change(struct emac_adapter *adpt, bool linkup)
+{
+	struct emac_sgmii *sgmii = &adpt->phy;
+	int ret;
+
+	if (linkup) {
+		/* Clear and enable interrupts */
+		ret = emac_sgmii_irq_clear(adpt, 0xff);
+		if (ret)
+			return ret;
+
+		writel(SGMII_ISR_MASK,
+		       sgmii->base + EMAC_SGMII_PHY_INTERRUPT_MASK);
+	} else {
+		/* Disable interrupts */
+		writel(0, sgmii->base + EMAC_SGMII_PHY_INTERRUPT_MASK);
+		synchronize_irq(sgmii->irq);
+	}
+
+	return 0;
+}
+
+static struct sgmii_ops fsm9900_ops = {
+	.init = emac_sgmii_init_fsm9900,
+	.open = emac_sgmii_common_open,
+	.close = emac_sgmii_common_close,
+	.link_change = emac_sgmii_common_link_change,
+	.reset = emac_sgmii_common_reset,
+};
+
+static struct sgmii_ops qdf2432_ops = {
+	.init = emac_sgmii_init_qdf2432,
+	.open = emac_sgmii_common_open,
+	.close = emac_sgmii_common_close,
+	.link_change = emac_sgmii_common_link_change,
+	.reset = emac_sgmii_common_reset,
+};
+
+#ifdef CONFIG_ACPI
+static struct sgmii_ops qdf2400_ops = {
+	.init = emac_sgmii_init_qdf2400,
+	.open = emac_sgmii_common_open,
+	.close = emac_sgmii_common_close,
+	.link_change = emac_sgmii_common_link_change,
+	.reset = emac_sgmii_common_reset,
+};
+#endif
+
+static int emac_sgmii_acpi_match(struct device *dev, void *data)
+{
+#ifdef CONFIG_ACPI
+	static const struct acpi_device_id match_table[] = {
+		{
+			.id = "QCOM8071",
+		},
+		{}
+	};
+	const struct acpi_device_id *id = acpi_match_device(match_table, dev);
+	struct sgmii_ops **ops = data;
+
+	if (id) {
+		acpi_handle handle = ACPI_HANDLE(dev);
+		unsigned long long hrv;
+		acpi_status status;
+
+		status = acpi_evaluate_integer(handle, "_HRV", NULL, &hrv);
+		if (status) {
+			if (status == AE_NOT_FOUND)
+				/* Older versions of the QDF2432 ACPI tables do
+				 * not have an _HRV property.
+				 */
+				hrv = 1;
+			else
+				/* Something is wrong with the tables */
+				return 0;
+		}
+
+		switch (hrv) {
+		case 1:
+			*ops = &qdf2432_ops;
+			return 1;
+		case 2:
+			*ops = &qdf2400_ops;
+			return 1;
+		}
+	}
+#endif
+
+	return 0;
+}
+
+static const struct of_device_id emac_sgmii_dt_match[] = {
+	{
+		.compatible = "qcom,fsm9900-emac-sgmii",
+		.data = &fsm9900_ops,
+	},
+	{
+		.compatible = "qcom,qdf2432-emac-sgmii",
+		.data = &qdf2432_ops,
+	},
+	{}
+};
+
+int emac_sgmii_config(struct platform_device *pdev, struct emac_adapter *adpt)
+{
+	struct platform_device *sgmii_pdev = NULL;
+	struct emac_sgmii *phy = &adpt->phy;
+	struct resource *res;
+	int ret;
+
+	if (has_acpi_companion(&pdev->dev)) {
+		struct device *dev;
+
+		dev = device_find_child(&pdev->dev, &phy->sgmii_ops,
+					emac_sgmii_acpi_match);
+
+		if (!dev) {
+			dev_warn(&pdev->dev, "cannot find internal phy node\n");
+			return 0;
+		}
+
+		sgmii_pdev = to_platform_device(dev);
+	} else {
+		const struct of_device_id *match;
+		struct device_node *np;
+
+		np = of_parse_phandle(pdev->dev.of_node, "internal-phy", 0);
+		if (!np) {
+			dev_err(&pdev->dev, "missing internal-phy property\n");
+			return -ENODEV;
+		}
+
+		sgmii_pdev = of_find_device_by_node(np);
+		of_node_put(np);
+		if (!sgmii_pdev) {
+			dev_err(&pdev->dev, "invalid internal-phy property\n");
+			return -ENODEV;
+		}
+
+		match = of_match_device(emac_sgmii_dt_match, &sgmii_pdev->dev);
+		if (!match) {
+			dev_err(&pdev->dev, "unrecognized internal phy node\n");
+			ret = -ENODEV;
+			goto error_put_device;
+		}
+
+		phy->sgmii_ops = (struct sgmii_ops *)match->data;
+	}
+
+	/* Base address is the first address */
+	res = platform_get_resource(sgmii_pdev, IORESOURCE_MEM, 0);
+	if (!res) {
+		ret = -EINVAL;
+		goto error_put_device;
+	}
+
+	phy->base = ioremap(res->start, resource_size(res));
+	if (!phy->base) {
+		ret = -ENOMEM;
+		goto error_put_device;
+	}
+
+	/* v2 SGMII has a per-lane digital digital, so parse it if it exists */
+	res = platform_get_resource(sgmii_pdev, IORESOURCE_MEM, 1);
+	if (res) {
+		phy->digital = ioremap(res->start, resource_size(res));
+		if (!phy->digital) {
+			ret = -ENOMEM;
+			goto error_unmap_base;
+		}
+	}
+
+	ret = emac_sgmii_init(adpt);
+	if (ret)
+		goto error;
+
+	emac_sgmii_link_init(adpt);
+
+	ret = platform_get_irq(sgmii_pdev, 0);
+	if (ret > 0)
+		phy->irq = ret;
+
+	/* We've remapped the addresses, so we don't need the device any
+	 * more.  of_find_device_by_node() says we should release it.
+	 */
+	put_device(&sgmii_pdev->dev);
+
+	return 0;
+
+error:
+	if (phy->digital)
+		iounmap(phy->digital);
+error_unmap_base:
+	iounmap(phy->base);
+error_put_device:
+	put_device(&sgmii_pdev->dev);
+
+	return ret;
+}