gpio: octeon_gpio: Add GPIO controller driver for Octeon

Add support for GPIO controllers found on Octeon II/III and Octeon TX
TX2 SoC platforms.

Signed-off-by: Aaron Williams <awilliams@marvell.com>
Signed-off-by: Suneel Garapati <sgarapati@marvell.com>
Signed-off-by: Stefan Roese <sr@denx.de>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
diff --git a/drivers/gpio/octeon_gpio.c b/drivers/gpio/octeon_gpio.c
new file mode 100644
index 0000000..45acaad
--- /dev/null
+++ b/drivers/gpio/octeon_gpio.c
@@ -0,0 +1,242 @@
+// SPDX-License-Identifier:    GPL-2.0
+/*
+ * Copyright (C) 2018 Marvell International Ltd.
+ *
+ * (C) Copyright 2011
+ * eInfochips Ltd. <www.einfochips.com>
+ * Written-by: Ajay Bhargav <ajay.bhargav@einfochips.com>
+ *
+ * (C) Copyright 2010
+ * Marvell Semiconductor <www.marvell.com>
+ */
+
+#include <dm.h>
+#include <pci.h>
+#include <pci_ids.h>
+#include <asm/gpio.h>
+#include <asm/io.h>
+#include <linux/bitfield.h>
+#include <linux/compat.h>
+#include <dt-bindings/gpio/gpio.h>
+
+/* Returns the bit value to write or read based on the offset */
+#define GPIO_BIT(x)		BIT_ULL((x) & 0x3f)
+
+#define GPIO_RX_DAT		0x00
+#define GPIO_TX_SET		0x08
+#define GPIO_TX_CLR		0x10
+#define GPIO_CONST		0x90	/* OcteonTX only */
+
+/* Offset to register-set for 2nd GPIOs (> 63), OcteonTX only */
+#define GPIO1_OFFSET		0x1400
+
+/* GPIO_CONST register bits */
+#define GPIO_CONST_GPIOS_MASK	GENMASK_ULL(7, 0)
+
+/* GPIO_BIT_CFG register bits */
+#define GPIO_BIT_CFG_TX_OE	BIT_ULL(0)
+#define GPIO_BIT_CFG_PIN_XOR	BIT_ULL(1)
+#define GPIO_BIT_CFG_INT_EN	BIT_ULL(2)
+#define GPIO_BIT_CFG_PIN_SEL_MASK GENMASK_ULL(26, 16)
+
+enum {
+	PROBE_PCI = 0,		/* PCI based probing */
+	PROBE_DT,		/* DT based probing */
+};
+
+struct octeon_gpio_data {
+	int probe;
+	u32 reg_offs;
+	u32 gpio_bit_cfg_offs;
+};
+
+struct octeon_gpio {
+	void __iomem *base;
+	const struct octeon_gpio_data *data;
+};
+
+/* Returns the offset to the output register based on the offset and value */
+static u32 gpio_tx_reg(int offset, int value)
+{
+	u32 ret;
+
+	ret = value ? GPIO_TX_SET : GPIO_TX_CLR;
+	if (offset > 63)
+		ret += GPIO1_OFFSET;
+
+	return ret;
+}
+
+/* Returns the offset to the input data register based on the offset */
+static u32 gpio_rx_dat_reg(int offset)
+{
+	u32 ret;
+
+	ret = GPIO_RX_DAT;
+	if (offset > 63)
+		ret += GPIO1_OFFSET;
+
+	return ret;
+}
+
+static int octeon_gpio_dir_input(struct udevice *dev, unsigned int offset)
+{
+	struct octeon_gpio *gpio = dev_get_priv(dev);
+
+	debug("%s(%s, %u)\n", __func__, dev->name, offset);
+	clrbits_64(gpio->base + gpio->data->gpio_bit_cfg_offs + 8 * offset,
+		   GPIO_BIT_CFG_TX_OE | GPIO_BIT_CFG_PIN_XOR |
+		   GPIO_BIT_CFG_INT_EN | GPIO_BIT_CFG_PIN_SEL_MASK);
+
+	return 0;
+}
+
+static int octeon_gpio_dir_output(struct udevice *dev, unsigned int offset,
+				  int value)
+{
+	struct octeon_gpio *gpio = dev_get_priv(dev);
+
+	debug("%s(%s, %u, %d)\n", __func__, dev->name, offset, value);
+	writeq(GPIO_BIT(offset), gpio->base + gpio->data->reg_offs +
+	       gpio_tx_reg(offset, value));
+
+	clrsetbits_64(gpio->base + gpio->data->gpio_bit_cfg_offs + 8 * offset,
+		      GPIO_BIT_CFG_PIN_SEL_MASK | GPIO_BIT_CFG_INT_EN,
+		      GPIO_BIT_CFG_TX_OE);
+
+	return 0;
+}
+
+static int octeon_gpio_get_value(struct udevice *dev, unsigned int offset)
+{
+	struct octeon_gpio *gpio = dev_get_priv(dev);
+	u64 reg = readq(gpio->base + gpio->data->reg_offs +
+			gpio_rx_dat_reg(offset));
+
+	debug("%s(%s, %u): value: %d\n", __func__, dev->name, offset,
+	      !!(reg & GPIO_BIT(offset)));
+
+	return !!(reg & GPIO_BIT(offset));
+}
+
+static int octeon_gpio_set_value(struct udevice *dev,
+				 unsigned int offset, int value)
+{
+	struct octeon_gpio *gpio = dev_get_priv(dev);
+
+	debug("%s(%s, %u, %d)\n", __func__, dev->name, offset, value);
+	writeq(GPIO_BIT(offset), gpio->base + gpio->data->reg_offs +
+	       gpio_tx_reg(offset, value));
+
+	return 0;
+}
+
+static int octeon_gpio_get_function(struct udevice *dev, unsigned int offset)
+{
+	struct octeon_gpio *gpio = dev_get_priv(dev);
+	u64 val = readq(gpio->base + gpio->data->gpio_bit_cfg_offs +
+			8 * offset);
+	int pin_sel;
+
+	debug("%s(%s, %u): GPIO_BIT_CFG: 0x%llx\n", __func__, dev->name,
+	      offset, val);
+	pin_sel = FIELD_GET(GPIO_BIT_CFG_PIN_SEL_MASK, val);
+	if (pin_sel)
+		return GPIOF_FUNC;
+	else if (val & GPIO_BIT_CFG_TX_OE)
+		return GPIOF_OUTPUT;
+	else
+		return GPIOF_INPUT;
+}
+
+static int octeon_gpio_xlate(struct udevice *dev, struct gpio_desc *desc,
+			     struct ofnode_phandle_args *args)
+{
+	if (args->args_count < 1)
+		return -EINVAL;
+
+	desc->offset = args->args[0];
+	desc->flags = 0;
+	if (args->args_count > 1) {
+		if (args->args[1] & GPIO_ACTIVE_LOW)
+			desc->flags |= GPIOD_ACTIVE_LOW;
+		/* In the future add tri-state flag support */
+	}
+	return 0;
+}
+
+static const struct dm_gpio_ops octeon_gpio_ops = {
+	.direction_input	= octeon_gpio_dir_input,
+	.direction_output	= octeon_gpio_dir_output,
+	.get_value		= octeon_gpio_get_value,
+	.set_value		= octeon_gpio_set_value,
+	.get_function		= octeon_gpio_get_function,
+	.xlate			= octeon_gpio_xlate,
+};
+
+static int octeon_gpio_probe(struct udevice *dev)
+{
+	struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(dev);
+	struct octeon_gpio *priv = dev_get_priv(dev);
+	char *end;
+
+	priv->data = (const struct octeon_gpio_data *)dev_get_driver_data(dev);
+
+	if (priv->data->probe == PROBE_PCI) {
+		priv->base = dm_pci_map_bar(dev, PCI_BASE_ADDRESS_0,
+					    PCI_REGION_MEM);
+		uc_priv->gpio_count = readq(priv->base +
+					    priv->data->reg_offs + GPIO_CONST) &
+			GPIO_CONST_GPIOS_MASK;
+	} else {
+		priv->base = dev_remap_addr(dev);
+		uc_priv->gpio_count = ofnode_read_u32_default(dev->node,
+							      "nr-gpios", 32);
+	}
+
+	if (!priv->base) {
+		debug("%s(%s): Could not get base address\n",
+		      __func__, dev->name);
+		return -ENODEV;
+	}
+
+	uc_priv->bank_name  = strdup(dev->name);
+	end = strchr(uc_priv->bank_name, '@');
+	end[0] = 'A' + dev->seq;
+	end[1] = '\0';
+
+	debug("%s(%s): base address: %p, pin count: %d\n",
+	      __func__, dev->name, priv->base, uc_priv->gpio_count);
+
+	return 0;
+}
+
+static const struct octeon_gpio_data gpio_octeon_data = {
+	.probe = PROBE_DT,
+	.reg_offs = 0x80,
+	.gpio_bit_cfg_offs = 0x100,
+};
+
+static const struct octeon_gpio_data gpio_octeontx_data = {
+	.probe = PROBE_PCI,
+	.reg_offs = 0x00,
+	.gpio_bit_cfg_offs = 0x400,
+};
+
+static const struct udevice_id octeon_gpio_ids[] = {
+	{ .compatible = "cavium,thunder-8890-gpio",
+	  .data = (ulong)&gpio_octeontx_data },
+	{ .compatible = "cavium,octeon-7890-gpio",
+	  .data = (ulong)&gpio_octeon_data },
+	{ }
+};
+
+U_BOOT_DRIVER(octeon_gpio) = {
+	.name	= "octeon_gpio",
+	.id	= UCLASS_GPIO,
+	.of_match = of_match_ptr(octeon_gpio_ids),
+	.probe = octeon_gpio_probe,
+	.priv_auto_alloc_size = sizeof(struct octeon_gpio),
+	.ops	= &octeon_gpio_ops,
+	.flags	= DM_FLAG_PRE_RELOC,
+};