[U-Boot] [U-BOOT PATCH] gpio: fu540: add support for DM based gpio driver for FU540 SoC

Sagar Shrikant Kadam sagar.kadam at sifive.com
Fri Aug 23 01:01:38 UTC 2019


This patch adds a DM based driver model for gpio controller present in
FU540-C000 SoC on HiFive Unleashed A00 board. This SoC has one GPIO
bank and 16 GPIO lines in total, out of which GPIO0 to GPIO9 and
GPIO15 are routed to the J1 header on the board.

This implementation is ported from linux based gpio driver submitted
for review by Wesley W. Terpstra <wesley at sifive.com> and/or Atish Patra
<atish.patra at wdc.com>. The linux driver can be referred
here [1]

[1]: https://lkml.org/lkml/2018/10/9/1103

Signed-off-by: Sagar Shrikant Kadam <sagar.kadam at sifive.com>
---
 arch/riscv/include/asm/arch-generic/gpio.h |  35 +++++++
 arch/riscv/include/asm/gpio.h              |   6 ++
 board/sifive/fu540/Kconfig                 |   3 +
 drivers/gpio/Kconfig                       |   8 ++
 drivers/gpio/Makefile                      |   1 +
 drivers/gpio/fu540-gpio.c                  | 145 +++++++++++++++++++++++++++++
 6 files changed, 198 insertions(+)
 create mode 100644 arch/riscv/include/asm/arch-generic/gpio.h
 create mode 100644 arch/riscv/include/asm/gpio.h
 create mode 100644 drivers/gpio/fu540-gpio.c

diff --git a/arch/riscv/include/asm/arch-generic/gpio.h b/arch/riscv/include/asm/arch-generic/gpio.h
new file mode 100644
index 0000000..bedb8d8
--- /dev/null
+++ b/arch/riscv/include/asm/arch-generic/gpio.h
@@ -0,0 +1,35 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright (C) 2019 SiFive, Inc.
+ */
+
+#ifndef _GPIO_FU540_H
+#define _GPIO_FU540_H
+
+#define GPIO_INPUT_VAL	0x00
+#define GPIO_INPUT_EN	0x04
+#define GPIO_OUTPUT_EN	0x08
+#define GPIO_OUTPUT_VAL	0x0C
+#define GPIO_RISE_IE	0x18
+#define GPIO_RISE_IP	0x1C
+#define GPIO_FALL_IE	0x20
+#define GPIO_FALL_IP	0x24
+#define GPIO_HIGH_IE	0x28
+#define GPIO_HIGH_IP	0x2C
+#define GPIO_LOW_IE	0x30
+#define GPIO_LOW_IP	0x34
+#define GPIO_OUTPUT_XOR	0x40
+
+#define NR_GPIOS	16
+
+enum gpio_state {
+	LOW,
+	HIGH
+};
+
+/* Details about a GPIO bank */
+struct fu540_gpio_platdata {
+	u8 *base;     /* address of registers in physical memory */
+};
+
+#endif /* _GPIO_FU540_H */
diff --git a/arch/riscv/include/asm/gpio.h b/arch/riscv/include/asm/gpio.h
new file mode 100644
index 0000000..008d756
--- /dev/null
+++ b/arch/riscv/include/asm/gpio.h
@@ -0,0 +1,6 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright 2018 SiFive, Inc.
+ */
+
+#include <asm-generic/gpio.h>
diff --git a/board/sifive/fu540/Kconfig b/board/sifive/fu540/Kconfig
index 5d65080..f939ed2 100644
--- a/board/sifive/fu540/Kconfig
+++ b/board/sifive/fu540/Kconfig
@@ -44,6 +44,9 @@ config BOARD_SPECIFIC_OPTIONS # dummy
 	imply MMC_SPI
 	imply MMC_BROKEN_CD
 	imply CMD_MMC
+	imply DM_GPIO
+	imply FU540_GPIO
+	imply CMD_GPIO
 	imply SMP
 
 endif
diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 7d9c97f..b93092a 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -280,6 +280,14 @@ config STM32_GPIO
 	  usable on many stm32 families like stm32f4/f7/h7 and stm32mp1.
 	  Tested on STM32F7.
 
+config FU540_GPIO
+	bool "FU540 GPIO Driver"
+	depends on DM_GPIO
+	help
+	  Device model driver for GPIO controller present in FU540 SoC. This
+	  driver enables GPIO interface on HiFive Unleashed A00 board a board
+	  from SiFive Inc. having FU540-C000 SoC.
+
 config MVEBU_GPIO
 	bool "Marvell MVEBU GPIO driver"
 	depends on DM_GPIO && ARCH_MVEBU
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index 4a8aa0f..238ad17 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -61,3 +61,4 @@ obj-$(CONFIG_$(SPL_)PCF8575_GPIO)	+= pcf8575_gpio.o
 obj-$(CONFIG_PM8916_GPIO)	+= pm8916_gpio.o
 obj-$(CONFIG_MT7621_GPIO)	+= mt7621_gpio.o
 obj-$(CONFIG_MSCC_SGPIO)	+= mscc_sgpio.o
+obj-$(CONFIG_FU540_GPIO)	+= fu540-gpio.o
diff --git a/drivers/gpio/fu540-gpio.c b/drivers/gpio/fu540-gpio.c
new file mode 100644
index 0000000..7761689
--- /dev/null
+++ b/drivers/gpio/fu540-gpio.c
@@ -0,0 +1,145 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * SiFive GPIO driver
+ *
+ * Copyright (C) 2019 SiFive, Inc.
+ *
+ * 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.
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <asm/arch/gpio.h>
+#include <asm/io.h>
+#include <errno.h>
+#include <asm-generic/gpio.h>
+
+static int fu540_gpio_probe(struct udevice *dev)
+{
+	struct fu540_gpio_platdata *plat = dev_get_platdata(dev);
+	struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(dev);
+	char name[18], *str;
+
+	sprintf(name, "gpio@%4p", plat->base);
+	str = strdup(name);
+	if (!str)
+		return -ENOMEM;
+	uc_priv->bank_name = str;
+	uc_priv->gpio_count = NR_GPIOS;
+
+	return 0;
+}
+
+static void fu540_update_gpio_reg(u8 *bptr, u32 offset, bool value)
+{
+	void __iomem *ptr = (void __iomem *)bptr;
+
+	u32 bit = BIT(offset), old = readl(ptr);
+
+	if (value)
+		writel(old | bit, ptr);
+	else
+		writel(old & ~bit, ptr);
+}
+
+static int fu540_gpio_direction_input(struct udevice *dev, u32 offset)
+{
+	struct fu540_gpio_platdata *plat = dev_get_platdata(dev);
+
+	if (offset > NR_GPIOS)
+		return -EINVAL;
+
+	/* Configure GPIO direction as input. */
+	fu540_update_gpio_reg(plat->base + GPIO_INPUT_EN,  offset, true);
+	fu540_update_gpio_reg(plat->base + GPIO_OUTPUT_EN, offset, false);
+
+	return 0;
+}
+
+static int fu540_gpio_direction_output(struct udevice *dev, u32 offset,
+				       int value)
+{
+	struct fu540_gpio_platdata *plat = dev_get_platdata(dev);
+
+	if (offset > NR_GPIOS)
+		return -EINVAL;
+
+	/* Configure GPIO direction as output. */
+	fu540_update_gpio_reg(plat->base + GPIO_OUTPUT_EN, offset, true);
+	fu540_update_gpio_reg(plat->base + GPIO_INPUT_EN,  offset, false);
+
+	/* Set the Output state of the PIN */
+	fu540_update_gpio_reg(plat->base + GPIO_OUTPUT_VAL, offset, value);
+
+	return 0;
+}
+
+static int fu540_gpio_get_value(struct udevice *dev, u32 offset)
+{
+	struct fu540_gpio_platdata *plat = dev_get_platdata(dev);
+	int val;
+	int dir;
+
+	if (offset > NR_GPIOS)
+		return -EINVAL;
+
+	/* Get direction of the pin OUTPUT=0 INPUT=1 */
+	dir = !(readl(plat->base + GPIO_OUTPUT_EN) & BIT(offset));
+
+	if (dir)
+		val = readl(plat->base + GPIO_INPUT_VAL) & BIT(offset);
+	else
+		val = readl(plat->base + GPIO_OUTPUT_VAL) & BIT(offset);
+
+	return val ? HIGH : LOW;
+}
+
+static int fu540_gpio_set_value(struct udevice *dev, u32 offset, int value)
+{
+	struct fu540_gpio_platdata *plat = dev_get_platdata(dev);
+
+	if (offset > NR_GPIOS)
+		return -EINVAL;
+
+	fu540_update_gpio_reg(plat->base + GPIO_OUTPUT_VAL, offset, value);
+
+	return 0;
+}
+
+static const struct udevice_id fu540_gpio_match[] = {
+	{ .compatible = "sifive,gpio0" },
+	{ }
+};
+
+static const struct dm_gpio_ops gpio_sifive_ops = {
+	.direction_input        = fu540_gpio_direction_input,
+	.direction_output       = fu540_gpio_direction_output,
+	.get_value              = fu540_gpio_get_value,
+	.set_value              = fu540_gpio_set_value,
+};
+
+static int fu540_gpio_ofdata_to_platdata(struct udevice *dev)
+{
+	struct fu540_gpio_platdata *plat = dev_get_platdata(dev);
+	fdt_addr_t addr;
+
+	addr = devfdt_get_addr(dev);
+	if (addr == FDT_ADDR_T_NONE)
+		return -EINVAL;
+
+	plat->base = (u8 *)addr;
+	return 0;
+}
+
+U_BOOT_DRIVER(gpio_sifive) = {
+	.name	= "gpio_sifive",
+	.id	= UCLASS_GPIO,
+	.of_match = fu540_gpio_match,
+	.ofdata_to_platdata = of_match_ptr(fu540_gpio_ofdata_to_platdata),
+	.platdata_auto_alloc_size = sizeof(struct fu540_gpio_platdata),
+	.ops	= &gpio_sifive_ops,
+	.probe	= fu540_gpio_probe,
+	.priv_auto_alloc_size	= sizeof(struct fu540_gpio_platdata),
+};
-- 
2.7.4



More information about the U-Boot mailing list