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path: root/drivers/brcm/iproc_gpio.c
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Diffstat (limited to 'drivers/brcm/iproc_gpio.c')
-rw-r--r--drivers/brcm/iproc_gpio.c232
1 files changed, 232 insertions, 0 deletions
diff --git a/drivers/brcm/iproc_gpio.c b/drivers/brcm/iproc_gpio.c
new file mode 100644
index 0000000..f61a3bc
--- /dev/null
+++ b/drivers/brcm/iproc_gpio.c
@@ -0,0 +1,232 @@
+/*
+ * Copyright (c) 2019-2020, Broadcom
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <assert.h>
+
+#include <drivers/gpio.h>
+#include <lib/mmio.h>
+#include <plat/common/platform.h>
+
+#include <iproc_gpio.h>
+#include <platform_def.h>
+
+#define IPROC_GPIO_DATA_IN_OFFSET 0x00
+#define IPROC_GPIO_DATA_OUT_OFFSET 0x04
+#define IPROC_GPIO_OUT_EN_OFFSET 0x08
+#define IPROC_GPIO_PAD_RES_OFFSET 0x34
+#define IPROC_GPIO_RES_EN_OFFSET 0x38
+
+#define PINMUX_OFFSET(gpio) ((gpio) * 4)
+#define PINCONF_OFFSET(gpio) ((gpio) * 4)
+#define PINCONF_PULL_UP BIT(4)
+#define PINCONF_PULL_DOWN BIT(5)
+
+/*
+ * iProc GPIO bank is always 0x200 per bank,
+ * with each bank supporting 32 GPIOs.
+ */
+#define GPIO_BANK_SIZE 0x200
+#define NGPIOS_PER_BANK 32
+#define GPIO_BANK(pin) ((pin) / NGPIOS_PER_BANK)
+
+#define IPROC_GPIO_REG(pin, reg) (GPIO_BANK(pin) * GPIO_BANK_SIZE + (reg))
+#define IPROC_GPIO_SHIFT(pin) ((pin) % NGPIOS_PER_BANK)
+
+#define MUX_GPIO_MODE 0x3
+
+/*
+ * @base: base address of the gpio controller
+ * @pinconf_base: base address of the pinconf
+ * @pinmux_base: base address of the mux controller
+ * @nr_gpios: maxinum number of GPIOs
+ */
+struct iproc_gpio {
+ uintptr_t base;
+ uintptr_t pinconf_base;
+ uintptr_t pinmux_base;
+ int nr_gpios;
+};
+
+static struct iproc_gpio iproc_gpio;
+
+static void gpio_set_bit(uintptr_t base, unsigned int reg, int gpio, bool set)
+{
+ unsigned int offset = IPROC_GPIO_REG(gpio, reg);
+ unsigned int shift = IPROC_GPIO_SHIFT(gpio);
+ uint32_t val;
+
+ val = mmio_read_32(base + offset);
+ if (set)
+ val |= BIT(shift);
+ else
+ val &= ~BIT(shift);
+
+ mmio_write_32(base + offset, val);
+}
+
+static bool gpio_get_bit(uintptr_t base, unsigned int reg, int gpio)
+{
+ unsigned int offset = IPROC_GPIO_REG(gpio, reg);
+ unsigned int shift = IPROC_GPIO_SHIFT(gpio);
+
+ return !!(mmio_read_32(base + offset) & BIT(shift));
+}
+
+static void mux_to_gpio(struct iproc_gpio *g, int gpio)
+{
+ /* mux pad to GPIO if IOPAD configuration is mandatory */
+ if (g->pinmux_base)
+ mmio_write_32(g->pinmux_base + PINMUX_OFFSET(gpio),
+ MUX_GPIO_MODE);
+}
+
+static void set_direction(int gpio, int direction)
+{
+ struct iproc_gpio *g = &iproc_gpio;
+ bool dir = (direction == GPIO_DIR_OUT) ? true : false;
+
+ assert(gpio < g->nr_gpios);
+
+ mux_to_gpio(g, gpio);
+ gpio_set_bit(g->base, IPROC_GPIO_OUT_EN_OFFSET, gpio, dir);
+}
+
+static int get_direction(int gpio)
+{
+ struct iproc_gpio *g = &iproc_gpio;
+ int dir;
+
+ assert(gpio < g->nr_gpios);
+
+ mux_to_gpio(g, gpio);
+ dir = gpio_get_bit(g->base, IPROC_GPIO_OUT_EN_OFFSET, gpio) ?
+ GPIO_DIR_OUT : GPIO_DIR_IN;
+
+ return dir;
+}
+
+static int get_value(int gpio)
+{
+ struct iproc_gpio *g = &iproc_gpio;
+ unsigned int offset;
+
+ assert(gpio < g->nr_gpios);
+
+ mux_to_gpio(g, gpio);
+
+ /*
+ * If GPIO is configured as output, read from the GPIO_OUT register;
+ * otherwise, read from the GPIO_IN register
+ */
+ offset = gpio_get_bit(g->base, IPROC_GPIO_OUT_EN_OFFSET, gpio) ?
+ IPROC_GPIO_DATA_OUT_OFFSET : IPROC_GPIO_DATA_IN_OFFSET;
+
+ return gpio_get_bit(g->base, offset, gpio);
+}
+
+static void set_value(int gpio, int val)
+{
+ struct iproc_gpio *g = &iproc_gpio;
+
+ assert(gpio < g->nr_gpios);
+
+ mux_to_gpio(g, gpio);
+
+ /* make sure GPIO is configured to output, and then set the value */
+ gpio_set_bit(g->base, IPROC_GPIO_OUT_EN_OFFSET, gpio, true);
+ gpio_set_bit(g->base, IPROC_GPIO_DATA_OUT_OFFSET, gpio, !!(val));
+}
+
+static int get_pull(int gpio)
+{
+ struct iproc_gpio *g = &iproc_gpio;
+ uint32_t val;
+
+ assert(gpio < g->nr_gpios);
+ mux_to_gpio(g, gpio);
+
+ /* when there's a valid pinconf_base, use it */
+ if (g->pinconf_base) {
+ val = mmio_read_32(g->pinconf_base + PINCONF_OFFSET(gpio));
+
+ if (val & PINCONF_PULL_UP)
+ return GPIO_PULL_UP;
+ else if (val & PINCONF_PULL_DOWN)
+ return GPIO_PULL_DOWN;
+ else
+ return GPIO_PULL_NONE;
+ }
+
+ /* no pinconf_base. fall back to GPIO internal pull control */
+ if (!gpio_get_bit(g->base, IPROC_GPIO_RES_EN_OFFSET, gpio))
+ return GPIO_PULL_NONE;
+
+ return gpio_get_bit(g->base, IPROC_GPIO_PAD_RES_OFFSET, gpio) ?
+ GPIO_PULL_UP : GPIO_PULL_DOWN;
+}
+
+static void set_pull(int gpio, int pull)
+{
+ struct iproc_gpio *g = &iproc_gpio;
+ uint32_t val;
+
+ assert(gpio < g->nr_gpios);
+ mux_to_gpio(g, gpio);
+
+ /* when there's a valid pinconf_base, use it */
+ if (g->pinconf_base) {
+ val = mmio_read_32(g->pinconf_base + PINCONF_OFFSET(gpio));
+
+ if (pull == GPIO_PULL_NONE) {
+ val &= ~(PINCONF_PULL_UP | PINCONF_PULL_DOWN);
+ } else if (pull == GPIO_PULL_UP) {
+ val |= PINCONF_PULL_UP;
+ val &= ~PINCONF_PULL_DOWN;
+ } else if (pull == GPIO_PULL_DOWN) {
+ val |= PINCONF_PULL_DOWN;
+ val &= ~PINCONF_PULL_UP;
+ } else {
+ return;
+ }
+ mmio_write_32(g->pinconf_base + PINCONF_OFFSET(gpio), val);
+ }
+
+ /* no pinconf_base. fall back to GPIO internal pull control */
+ if (pull == GPIO_PULL_NONE) {
+ gpio_set_bit(g->base, IPROC_GPIO_RES_EN_OFFSET, gpio, false);
+ return;
+ }
+
+ /* enable pad register and pull up or down */
+ gpio_set_bit(g->base, IPROC_GPIO_RES_EN_OFFSET, gpio, true);
+ gpio_set_bit(g->base, IPROC_GPIO_PAD_RES_OFFSET, gpio,
+ !!(pull == GPIO_PULL_UP));
+}
+
+const gpio_ops_t iproc_gpio_ops = {
+ .get_direction = get_direction,
+ .set_direction = set_direction,
+ .get_value = get_value,
+ .set_value = set_value,
+ .get_pull = get_pull,
+ .set_pull = set_pull,
+};
+
+void iproc_gpio_init(uintptr_t base, int nr_gpios, uintptr_t pinmux_base,
+ uintptr_t pinconf_base)
+{
+ iproc_gpio.base = base;
+ iproc_gpio.nr_gpios = nr_gpios;
+
+ /* pinmux/pinconf base is optional for some SoCs */
+ if (pinmux_base)
+ iproc_gpio.pinmux_base = pinmux_base;
+
+ if (pinconf_base)
+ iproc_gpio.pinconf_base = pinconf_base;
+
+ gpio_init(&iproc_gpio_ops);
+}