arm: gpio: add pl061 driver

Add PL061 GPIO driver that is depend on gpio framework.

Signed-off-by: Haojian Zhuang <haojian.zhuang@linaro.org>

1 files changed, 165 insertions, 0 deletions

diff --git a/drivers/arm/pl061/pl061_gpio.c b/drivers/arm/pl061/pl061_gpio.c
new file mode 100644
index 00000000..fca00565
--- /dev/null
+++ b/drivers/arm/pl061/pl061_gpio.c
@@ -0,0 +1,165 @@
+/*
+ * Copyright (c) 2016, ARM Limited and Contributors. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * Redistributions of source code must retain the above copyright notice, this
+ * list of conditions and the following disclaimer.
+ *
+ * Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ *
+ * Neither the name of ARM nor the names of its contributors may be used
+ * to endorse or promote products derived from this software without specific
+ * prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ * ARM PL061 GPIO Driver.
+ * Reference to ARM DDI 0190B document.
+ *
+ */
+
+#include <assert.h>
+#include <cassert.h>
+#include <debug.h>
+#include <errno.h>
+#include <gpio.h>
+#include <mmio.h>
+#include <pl061_gpio.h>
+
+#if !PLAT_PL061_MAX_GPIOS
+# define PLAT_PL061_MAX_GPIOS	32
+#endif	/* PLAT_PL061_MAX_GPIOS */
+
+CASSERT(PLAT_PL061_MAX_GPIOS > 0, assert_plat_pl061_max_gpios);
+
+#define MAX_GPIO_DEVICES	((PLAT_PL061_MAX_GPIOS +		\
+				 (GPIOS_PER_PL061 - 1)) / GPIOS_PER_PL061)
+
+#define PL061_GPIO_DIR		0x400
+
+#define GPIOS_PER_PL061		8
+#define BIT(nr)			(1UL << (nr))
+
+static int pl061_get_direction(int gpio);
+static void pl061_set_direction(int gpio, int direction);
+static int pl061_get_value(int gpio);
+static void pl061_set_value(int gpio, int value);
+
+static uintptr_t pl061_reg_base[MAX_GPIO_DEVICES];
+
+static const gpio_ops_t pl061_gpio_ops = {
+	.get_direction	= pl061_get_direction,
+	.set_direction	= pl061_set_direction,
+	.get_value	= pl061_get_value,
+	.set_value	= pl061_set_value,
+};
+
+static int pl061_get_direction(int gpio)
+{
+	uintptr_t base_addr;
+	unsigned int data, offset;
+
+	assert((gpio >= 0) && (gpio < PLAT_PL061_MAX_GPIOS));
+
+	base_addr = pl061_reg_base[gpio / GPIOS_PER_PL061];
+	offset = gpio % GPIOS_PER_PL061;
+	data = mmio_read_8(base_addr + PL061_GPIO_DIR);
+	if (data & BIT(offset))
+		return GPIO_DIR_OUT;
+	return GPIO_DIR_IN;
+}
+
+static void pl061_set_direction(int gpio, int direction)
+{
+	uintptr_t base_addr;
+	unsigned int data, offset;
+
+	assert((gpio >= 0) && (gpio < PLAT_PL061_MAX_GPIOS));
+
+	base_addr = pl061_reg_base[gpio / GPIOS_PER_PL061];
+	offset = gpio % GPIOS_PER_PL061;
+	if (direction == GPIO_DIR_OUT) {
+		data = mmio_read_8(base_addr + PL061_GPIO_DIR) | BIT(offset);
+		mmio_write_8(base_addr + PL061_GPIO_DIR, data);
+	} else {
+		data = mmio_read_8(base_addr + PL061_GPIO_DIR) & ~BIT(offset);
+		mmio_write_8(base_addr + PL061_GPIO_DIR, data);
+	}
+}
+
+/*
+ * The offset of GPIODATA register is 0.
+ * The values read from GPIODATA are determined for each bit, by the mask bit
+ * derived from the address used to access the data register, PADDR[9:2].
+ * Bits that are 1 in the address mask cause the corresponding bits in GPIODATA
+ * to be read, and bits that are 0 in the address mask cause the corresponding
+ * bits in GPIODATA to be read as 0, regardless of their value.
+ */
+static int pl061_get_value(int gpio)
+{
+	uintptr_t base_addr;
+	unsigned int offset;
+
+	assert((gpio >= 0) && (gpio < PLAT_PL061_MAX_GPIOS));
+
+	base_addr = pl061_reg_base[gpio / GPIOS_PER_PL061];
+	offset = gpio % GPIOS_PER_PL061;
+	if (mmio_read_8(base_addr + BIT(offset + 2)))
+		return GPIO_LEVEL_HIGH;
+	return GPIO_LEVEL_LOW;
+}
+
+/*
+ * In order to write GPIODATA, the corresponding bits in the mask, resulting
+ * from the address bus, PADDR[9:2], must be HIGH. Otherwise the bit values
+ * remain unchanged by the write.
+ */
+static void pl061_set_value(int gpio, int value)
+{
+	uintptr_t base_addr;
+	int offset;
+
+	assert((gpio >= 0) && (gpio < PLAT_PL061_MAX_GPIOS));
+
+	base_addr = pl061_reg_base[gpio / GPIOS_PER_PL061];
+	offset = gpio % GPIOS_PER_PL061;
+	if (value == GPIO_LEVEL_HIGH)
+		mmio_write_8(base_addr + BIT(offset + 2), BIT(offset));
+	else
+		mmio_write_8(base_addr + BIT(offset + 2), 0);
+}
+
+
+/*
+ * Register the PL061 GPIO controller with a base address and the offset
+ * of start pin in this GPIO controller.
+ * This function is called after pl061_gpio_ops_init().
+ */
+void pl061_gpio_register(uintptr_t base_addr, int gpio_dev)
+{
+	assert((gpio_dev >= 0) && (gpio_dev < MAX_GPIO_DEVICES));
+
+	pl061_reg_base[gpio_dev] = base_addr;
+}
+
+/*
+ * Initialize PL061 GPIO controller with the total GPIO numbers in SoC.
+ */
+void pl061_gpio_init(void)
+{
+	gpio_init(&pl061_gpio_ops);
+}