zephyr/drivers/gpio/gpio_sifive.c

477 lines
10 KiB
C

/*
* Copyright (c) 2017 Jean-Paul Etienne <fractalclone@gmail.com>
*
* SPDX-License-Identifier: Apache-2.0
*/
/**
* @file GPIO driver for the SiFive Freedom Processor
*/
#include <errno.h>
#include <kernel.h>
#include <device.h>
#include <soc.h>
#include <gpio.h>
#include <misc/util.h>
#include "gpio_utils.h"
typedef void (*sifive_cfg_func_t)(void);
/* sifive GPIO register-set structure */
struct gpio_sifive_t {
unsigned int in_val;
unsigned int in_en;
unsigned int out_en;
unsigned int out_val;
unsigned int pue;
unsigned int ds;
unsigned int rise_ie;
unsigned int rise_ip;
unsigned int fall_ie;
unsigned int fall_ip;
unsigned int high_ie;
unsigned int high_ip;
unsigned int low_ie;
unsigned int low_ip;
unsigned int iof_en;
unsigned int iof_sel;
unsigned int invert;
};
struct gpio_sifive_config {
u32_t gpio_base_addr;
u32_t gpio_irq_base;
sifive_cfg_func_t gpio_cfg_func;
};
struct gpio_sifive_data {
/* list of callbacks */
sys_slist_t cb;
};
/* Helper Macros for GPIO */
#define DEV_GPIO_CFG(dev) \
((const struct gpio_sifive_config * const)(dev)->config->config_info)
#define DEV_GPIO(dev) \
((volatile struct gpio_sifive_t *)(DEV_GPIO_CFG(dev))->gpio_base_addr)
#define DEV_GPIO_DATA(dev) \
((struct gpio_sifive_data *)(dev)->driver_data)
static void gpio_sifive_irq_handler(void *arg)
{
struct device *dev = (struct device *)arg;
struct gpio_sifive_data *data = DEV_GPIO_DATA(dev);
volatile struct gpio_sifive_t *gpio = DEV_GPIO(dev);
const struct gpio_sifive_config *cfg = DEV_GPIO_CFG(dev);
int pin_mask;
/* Get the pin number generating the interrupt */
pin_mask = 1 << (riscv_plic_get_irq() -
(cfg->gpio_irq_base - RISCV_MAX_GENERIC_IRQ));
/* Call the corresponding callback registered for the pin */
gpio_fire_callbacks(&data->cb, dev, pin_mask);
/*
* Write to either the rise_ip, fall_ip, high_ip or low_ip registers
* to indicate to GPIO controller that interrupt for the corresponding
* pin has been handled.
*/
if (gpio->rise_ip & pin_mask)
gpio->rise_ip = pin_mask;
else if (gpio->fall_ip & pin_mask)
gpio->fall_ip = pin_mask;
else if (gpio->high_ip & pin_mask)
gpio->high_ip = pin_mask;
else if (gpio->low_ip & pin_mask)
gpio->low_ip = pin_mask;
}
/**
* @brief Configure pin
*
* @param dev Device structure
* @param access_op Access operation
* @param pin The pin number
* @param flags Flags of pin or port
*
* @return 0 if successful, failed otherwise
*/
static int gpio_sifive_config(struct device *dev,
int access_op,
u32_t pin,
int flags)
{
volatile struct gpio_sifive_t *gpio = DEV_GPIO(dev);
if (access_op != GPIO_ACCESS_BY_PIN)
return -ENOTSUP;
if (pin >= SIFIVE_PINMUX_PINS)
return -EINVAL;
/* Configure gpio direction */
if (flags & GPIO_DIR_OUT) {
gpio->in_en &= ~BIT(pin);
gpio->out_en |= BIT(pin);
/*
* Account for polarity only for GPIO_DIR_OUT.
* invert register handles only output gpios
*/
if (flags & GPIO_POL_INV)
gpio->invert |= BIT(pin);
else
gpio->invert &= ~BIT(pin);
} else {
gpio->out_en &= ~BIT(pin);
gpio->in_en |= BIT(pin);
/* Polarity inversion is not supported for input gpio */
if (flags & GPIO_POL_INV)
return -EINVAL;
/*
* Pull-up can be configured only for input gpios.
* Only Pull-up can be enabled or disabled.
*/
if ((flags & GPIO_PUD_MASK) == GPIO_PUD_PULL_DOWN)
return -EINVAL;
if ((flags & GPIO_PUD_MASK) == GPIO_PUD_PULL_UP)
gpio->pue |= BIT(pin);
else
gpio->pue &= ~BIT(pin);
}
/*
* Configure interrupt if GPIO_INT is set.
* Here, we just configure the gpio interrupt behavior,
* we do not enable/disable interrupt for a particular
* gpio.
* Interrupt for a gpio is:
* 1) enabled only via a call to gpio_sifive_enable_callback.
* 2) disabled only via a call to gpio_sifive_disabled_callback.
*/
if (!(flags & GPIO_INT))
return 0;
/*
* Interrupt cannot be set for GPIO_DIR_OUT
*/
if (flags & GPIO_DIR_OUT)
return -EINVAL;
/* Edge or Level triggered ? */
if (flags & GPIO_INT_EDGE) {
gpio->high_ie &= ~BIT(pin);
gpio->low_ie &= ~BIT(pin);
/* Rising Edge, Falling Edge or Double Edge ? */
if (flags & GPIO_INT_DOUBLE_EDGE) {
gpio->rise_ie |= BIT(pin);
gpio->fall_ie |= BIT(pin);
} else if (flags & GPIO_INT_ACTIVE_HIGH) {
gpio->rise_ie |= BIT(pin);
gpio->fall_ie &= ~BIT(pin);
} else {
gpio->rise_ie &= ~BIT(pin);
gpio->fall_ie |= BIT(pin);
}
} else {
gpio->rise_ie &= ~BIT(pin);
gpio->fall_ie &= ~BIT(pin);
/* Level High ? */
if (flags & GPIO_INT_ACTIVE_HIGH) {
gpio->high_ie |= BIT(pin);
gpio->low_ie &= ~BIT(pin);
} else {
gpio->high_ie &= ~BIT(pin);
gpio->low_ie |= BIT(pin);
}
}
return 0;
}
/**
* @brief Set the pin
*
* @param dev Device struct
* @param access_op Access operation
* @param pin The pin number
* @param value Value to set (0 or 1)
*
* @return 0 if successful, failed otherwise
*/
static int gpio_sifive_write(struct device *dev,
int access_op,
u32_t pin,
u32_t value)
{
volatile struct gpio_sifive_t *gpio = DEV_GPIO(dev);
if (access_op != GPIO_ACCESS_BY_PIN)
return -ENOTSUP;
if (pin >= SIFIVE_PINMUX_PINS)
return -EINVAL;
/* If pin is configured as input return with error */
if (gpio->in_en & BIT(pin))
return -EINVAL;
if (value)
gpio->out_val |= BIT(pin);
else
gpio->out_val &= ~BIT(pin);
return 0;
}
/**
* @brief Read the pin
*
* @param dev Device struct
* @param access_op Access operation
* @param pin The pin number
* @param value Value of input pin(s)
*
* @return 0 if successful, failed otherwise
*/
static int gpio_sifive_read(struct device *dev,
int access_op,
u32_t pin,
u32_t *value)
{
volatile struct gpio_sifive_t *gpio = DEV_GPIO(dev);
if (access_op != GPIO_ACCESS_BY_PIN)
return -ENOTSUP;
if (pin >= SIFIVE_PINMUX_PINS)
return -EINVAL;
/*
* If gpio is configured as output,
* read gpio value from out_val register,
* otherwise read gpio value from in_val register
*/
if (gpio->out_en & BIT(pin))
*value = !!(gpio->out_val & BIT(pin));
else
*value = !!(gpio->in_val & BIT(pin));
return 0;
}
static int gpio_sifive_manage_callback(struct device *dev,
struct gpio_callback *callback,
bool set)
{
struct gpio_sifive_data *data = DEV_GPIO_DATA(dev);
return gpio_manage_callback(&data->cb, callback, set);
}
static int gpio_sifive_enable_callback(struct device *dev,
int access_op,
u32_t pin)
{
const struct gpio_sifive_config *cfg = DEV_GPIO_CFG(dev);
if (access_op != GPIO_ACCESS_BY_PIN)
return -ENOTSUP;
if (pin >= SIFIVE_PINMUX_PINS)
return -EINVAL;
/* Enable interrupt for the pin at PLIC level */
irq_enable(cfg->gpio_irq_base + pin);
return 0;
}
static int gpio_sifive_disable_callback(struct device *dev,
int access_op,
u32_t pin)
{
const struct gpio_sifive_config *cfg = DEV_GPIO_CFG(dev);
if (access_op != GPIO_ACCESS_BY_PIN)
return -ENOTSUP;
if (pin >= SIFIVE_PINMUX_PINS)
return -EINVAL;
/* Disable interrupt for the pin at PLIC level */
irq_disable(cfg->gpio_irq_base + pin);
return 0;
}
static const struct gpio_driver_api gpio_sifive_driver = {
.config = gpio_sifive_config,
.write = gpio_sifive_write,
.read = gpio_sifive_read,
.manage_callback = gpio_sifive_manage_callback,
.enable_callback = gpio_sifive_enable_callback,
.disable_callback = gpio_sifive_disable_callback,
};
/**
* @brief Initialize a GPIO controller
*
* Perform basic initialization of a GPIO controller
*
* @param dev GPIO device struct
*
* @return 0
*/
static int gpio_sifive_init(struct device *dev)
{
volatile struct gpio_sifive_t *gpio = DEV_GPIO(dev);
const struct gpio_sifive_config *cfg = DEV_GPIO_CFG(dev);
/* Ensure that all gpio registers are reset to 0 initially */
gpio->in_en = 0U;
gpio->out_en = 0U;
gpio->pue = 0U;
gpio->rise_ie = 0U;
gpio->fall_ie = 0U;
gpio->high_ie = 0U;
gpio->low_ie = 0U;
gpio->invert = 0U;
/* Setup IRQ handler for each gpio pin */
cfg->gpio_cfg_func();
return 0;
}
static void gpio_sifive_cfg_0(void);
static const struct gpio_sifive_config gpio_sifive_config0 = {
.gpio_base_addr = DT_SIFIVE_GPIO_0_BASE_ADDR,
.gpio_irq_base = RISCV_MAX_GENERIC_IRQ + DT_SIFIVE_GPIO_0_IRQ_0,
.gpio_cfg_func = gpio_sifive_cfg_0,
};
static struct gpio_sifive_data gpio_sifive_data0;
DEVICE_AND_API_INIT(gpio_sifive_0, CONFIG_GPIO_SIFIVE_GPIO_NAME,
gpio_sifive_init,
&gpio_sifive_data0, &gpio_sifive_config0,
POST_KERNEL, CONFIG_KERNEL_INIT_PRIORITY_DEVICE,
&gpio_sifive_driver);
#define IRQ_INIT(n) \
IRQ_CONNECT(RISCV_MAX_GENERIC_IRQ + DT_SIFIVE_GPIO_0_IRQ_##n, \
CONFIG_GPIO_SIFIVE_##n##_PRIORITY, \
gpio_sifive_irq_handler, \
DEVICE_GET(gpio_sifive_0), \
0);
static void gpio_sifive_cfg_0(void)
{
#ifdef DT_SIFIVE_GPIO_0_IRQ_0
IRQ_INIT(0);
#endif
#ifdef DT_SIFIVE_GPIO_0_IRQ_1
IRQ_INIT(1);
#endif
#ifdef DT_SIFIVE_GPIO_0_IRQ_2
IRQ_INIT(2);
#endif
#ifdef DT_SIFIVE_GPIO_0_IRQ_3
IRQ_INIT(3);
#endif
#ifdef DT_SIFIVE_GPIO_0_IRQ_4
IRQ_INIT(4);
#endif
#ifdef DT_SIFIVE_GPIO_0_IRQ_5
IRQ_INIT(5);
#endif
#ifdef DT_SIFIVE_GPIO_0_IRQ_6
IRQ_INIT(6);
#endif
#ifdef DT_SIFIVE_GPIO_0_IRQ_7
IRQ_INIT(7);
#endif
#ifdef DT_SIFIVE_GPIO_0_IRQ_8
IRQ_INIT(8);
#endif
#ifdef DT_SIFIVE_GPIO_0_IRQ_9
IRQ_INIT(9);
#endif
#ifdef DT_SIFIVE_GPIO_0_IRQ_10
IRQ_INIT(10);
#endif
#ifdef DT_SIFIVE_GPIO_0_IRQ_11
IRQ_INIT(11);
#endif
#ifdef DT_SIFIVE_GPIO_0_IRQ_12
IRQ_INIT(12);
#endif
#ifdef DT_SIFIVE_GPIO_0_IRQ_13
IRQ_INIT(13);
#endif
#ifdef DT_SIFIVE_GPIO_0_IRQ_14
IRQ_INIT(14);
#endif
#ifdef DT_SIFIVE_GPIO_0_IRQ_15
IRQ_INIT(15);
#endif
#ifdef DT_SIFIVE_GPIO_0_IRQ_16
IRQ_INIT(16);
#endif
#ifdef DT_SIFIVE_GPIO_0_IRQ_17
IRQ_INIT(17);
#endif
#ifdef DT_SIFIVE_GPIO_0_IRQ_18
IRQ_INIT(18);
#endif
#ifdef DT_SIFIVE_GPIO_0_IRQ_19
IRQ_INIT(19);
#endif
#ifdef DT_SIFIVE_GPIO_0_IRQ_20
IRQ_INIT(20);
#endif
#ifdef DT_SIFIVE_GPIO_0_IRQ_21
IRQ_INIT(21);
#endif
#ifdef DT_SIFIVE_GPIO_0_IRQ_22
IRQ_INIT(22);
#endif
#ifdef DT_SIFIVE_GPIO_0_IRQ_23
IRQ_INIT(23);
#endif
#ifdef DT_SIFIVE_GPIO_0_IRQ_24
IRQ_INIT(24);
#endif
#ifdef DT_SIFIVE_GPIO_0_IRQ_25
IRQ_INIT(25);
#endif
#ifdef DT_SIFIVE_GPIO_0_IRQ_26
IRQ_INIT(26);
#endif
#ifdef DT_SIFIVE_GPIO_0_IRQ_27
IRQ_INIT(27);
#endif
#ifdef DT_SIFIVE_GPIO_0_IRQ_28
IRQ_INIT(28);
#endif
#ifdef DT_SIFIVE_GPIO_0_IRQ_29
IRQ_INIT(29);
#endif
#ifdef DT_SIFIVE_GPIO_0_IRQ_30
IRQ_INIT(30);
#endif
#ifdef DT_SIFIVE_GPIO_0_IRQ_31
IRQ_INIT(31);
#endif
}