spi: iproc-qspi: Add Broadcom iProc SoCs support

This spi driver uses the common spi-bcm-qspi driver and implements iProc
SoCs specific interrupt controller. The common driver now calls the SoC
handlers when present. Adding support for both muxed l1 and unmuxed interrupt
sources.

Signed-off-by: Kamal Dasu <[email protected]>
Signed-off-by: Yendapally Reddy Dhananjaya Reddy <[email protected]>
Signed-off-by: Mark Brown <[email protected]>
diff --git a/drivers/spi/spi-iproc-qspi.c b/drivers/spi/spi-iproc-qspi.c
new file mode 100644
index 0000000..be6ccb2
--- /dev/null
+++ b/drivers/spi/spi-iproc-qspi.c
@@ -0,0 +1,163 @@
+/*
+ * Copyright 2016 Broadcom Limited
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License 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.
+ */
+
+#include <linux/device.h>
+#include <linux/io.h>
+#include <linux/ioport.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+#include "spi-bcm-qspi.h"
+
+#define INTR_BASE_BIT_SHIFT			0x02
+#define INTR_COUNT				0x07
+
+struct bcm_iproc_intc {
+	struct bcm_qspi_soc_intc soc_intc;
+	struct platform_device *pdev;
+	void __iomem *int_reg;
+	void __iomem *int_status_reg;
+	spinlock_t soclock;
+	bool big_endian;
+};
+
+static u32 bcm_iproc_qspi_get_l2_int_status(struct bcm_qspi_soc_intc *soc_intc)
+{
+	struct bcm_iproc_intc *priv =
+			container_of(soc_intc, struct bcm_iproc_intc, soc_intc);
+	void __iomem *mmio = priv->int_status_reg;
+	int i;
+	u32 val = 0, sts = 0;
+
+	for (i = 0; i < INTR_COUNT; i++) {
+		if (bcm_qspi_readl(priv->big_endian, mmio + (i * 4)))
+			val |= 1UL << i;
+	}
+
+	if (val & INTR_MSPI_DONE_MASK)
+		sts |= MSPI_DONE;
+
+	if (val & BSPI_LR_INTERRUPTS_ALL)
+		sts |= BSPI_DONE;
+
+	if (val & BSPI_LR_INTERRUPTS_ERROR)
+		sts |= BSPI_ERR;
+
+	return sts;
+}
+
+static void bcm_iproc_qspi_int_ack(struct bcm_qspi_soc_intc *soc_intc, int type)
+{
+	struct bcm_iproc_intc *priv =
+			container_of(soc_intc, struct bcm_iproc_intc, soc_intc);
+	void __iomem *mmio = priv->int_status_reg;
+	u32 mask = get_qspi_mask(type);
+	int i;
+
+	for (i = 0; i < INTR_COUNT; i++) {
+		if (mask & (1UL << i))
+			bcm_qspi_writel(priv->big_endian, 1, mmio + (i * 4));
+	}
+}
+
+static void bcm_iproc_qspi_int_set(struct bcm_qspi_soc_intc *soc_intc, int type,
+				   bool en)
+{
+	struct bcm_iproc_intc *priv =
+			container_of(soc_intc, struct bcm_iproc_intc, soc_intc);
+	void __iomem *mmio = priv->int_reg;
+	u32 mask = get_qspi_mask(type);
+	u32 val;
+	unsigned long flags;
+
+	spin_lock_irqsave(&priv->soclock, flags);
+
+	val = bcm_qspi_readl(priv->big_endian, mmio);
+
+	if (en)
+		val = val | (mask << INTR_BASE_BIT_SHIFT);
+	else
+		val = val & ~(mask << INTR_BASE_BIT_SHIFT);
+
+	bcm_qspi_writel(priv->big_endian, val, mmio);
+
+	spin_unlock_irqrestore(&priv->soclock, flags);
+}
+
+static int bcm_iproc_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct bcm_iproc_intc *priv;
+	struct bcm_qspi_soc_intc *soc_intc;
+	struct resource *res;
+
+	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+	soc_intc = &priv->soc_intc;
+	priv->pdev = pdev;
+
+	spin_lock_init(&priv->soclock);
+
+	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "intr_regs");
+	priv->int_reg = devm_ioremap_resource(dev, res);
+	if (IS_ERR(priv->int_reg))
+		return PTR_ERR(priv->int_reg);
+
+	res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
+					   "intr_status_reg");
+	priv->int_status_reg = devm_ioremap_resource(dev, res);
+	if (IS_ERR(priv->int_status_reg))
+		return PTR_ERR(priv->int_status_reg);
+
+	priv->big_endian = of_device_is_big_endian(dev->of_node);
+
+	bcm_iproc_qspi_int_ack(soc_intc, MSPI_BSPI_DONE);
+	bcm_iproc_qspi_int_set(soc_intc, MSPI_BSPI_DONE, false);
+
+	soc_intc->bcm_qspi_int_ack = bcm_iproc_qspi_int_ack;
+	soc_intc->bcm_qspi_int_set = bcm_iproc_qspi_int_set;
+	soc_intc->bcm_qspi_get_int_status = bcm_iproc_qspi_get_l2_int_status;
+
+	return bcm_qspi_probe(pdev, soc_intc);
+}
+
+static int bcm_iproc_remove(struct platform_device *pdev)
+{
+	return bcm_qspi_remove(pdev);
+}
+
+static const struct of_device_id bcm_iproc_of_match[] = {
+	{ .compatible = "brcm,spi-nsp-qspi" },
+	{ .compatible = "brcm,spi-ns2-qspi" },
+	{},
+};
+MODULE_DEVICE_TABLE(of, bcm_iproc_of_match);
+
+static struct platform_driver bcm_iproc_driver = {
+	.probe			= bcm_iproc_probe,
+	.remove			= bcm_iproc_remove,
+	.driver = {
+		.name		= "bcm_iproc",
+		.pm		= &bcm_qspi_pm_ops,
+		.of_match_table = bcm_iproc_of_match,
+	}
+};
+module_platform_driver(bcm_iproc_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Kamal Dasu");
+MODULE_DESCRIPTION("SPI flash driver for Broadcom iProc SoCs");