coreboot-libre-fam15h-rdimm/3rdparty/chromeec/chip/stm32/gpio.c

162 lines
3.8 KiB
C

/* Copyright 2014 The Chromium OS Authors. All rights reserved.
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
/* GPIO module for Chrome EC */
#include "clock.h"
#include "common.h"
#include "console.h"
#include "gpio_chip.h"
#include "hooks.h"
#include "registers.h"
#include "system.h"
#include "task.h"
#include "util.h"
/* Console output macros */
#define CPRINTS(format, args...) cprints(CC_GPIO, format, ## args)
/* For each EXTI bit, record which GPIO entry is using it */
static uint8_t exti_events[16];
void gpio_pre_init(void)
{
const struct gpio_info *g = gpio_list;
int is_warm = system_is_reboot_warm();
int i;
/* Required to configure external IRQ lines (SYSCFG_EXTICRn) */
#ifdef CHIP_FAMILY_STM32H7
STM32_RCC_APB4ENR |= STM32_RCC_SYSCFGEN;
#else
STM32_RCC_APB2ENR |= STM32_RCC_SYSCFGEN;
#endif
/* Delay 1 APB clock cycle after the clock is enabled */
clock_wait_bus_cycles(BUS_APB, 1);
/* Disable all GPIO EXTINTs (EXTINT0..15) left enabled after sysjump. */
STM32_EXTI_IMR &= ~0xFFFF;
if (!is_warm)
gpio_enable_clocks();
/* Set all GPIOs to defaults */
for (i = 0; i < GPIO_COUNT; i++, g++) {
int flags = g->flags;
if (flags & GPIO_DEFAULT)
continue;
/*
* If this is a warm reboot, don't set the output levels or
* we'll shut off the AP.
*/
if (is_warm)
flags &= ~(GPIO_LOW | GPIO_HIGH);
/* Set up GPIO based on flags */
gpio_set_flags_by_mask(g->port, g->mask, flags);
}
}
test_mockable int gpio_get_level(enum gpio_signal signal)
{
return !!(STM32_GPIO_IDR(gpio_list[signal].port) &
gpio_list[signal].mask);
}
void gpio_set_level(enum gpio_signal signal, int value)
{
STM32_GPIO_BSRR(gpio_list[signal].port) =
gpio_list[signal].mask << (value ? 0 : 16);
}
int gpio_enable_interrupt(enum gpio_signal signal)
{
const struct gpio_info *g = gpio_list + signal;
const struct gpio_info *g_old = gpio_list;
uint32_t bit, group, shift, bank;
/* Fail if not implemented or no interrupt handler */
if (!g->mask || signal >= GPIO_IH_COUNT)
return EC_ERROR_INVAL;
bit = GPIO_MASK_TO_NUM(g->mask);
g_old += exti_events[bit];
if ((exti_events[bit]) && (exti_events[bit] != signal)) {
CPRINTS("Overriding %s with %s on EXTI%d",
g_old->name, g->name, bit);
}
exti_events[bit] = signal;
group = bit / 4;
shift = (bit % 4) * 4;
bank = (g->port - STM32_GPIOA_BASE) / 0x400;
STM32_SYSCFG_EXTICR(group) = (STM32_SYSCFG_EXTICR(group) &
~(0xF << shift)) | (bank << shift);
STM32_EXTI_IMR |= g->mask;
return EC_SUCCESS;
}
int gpio_disable_interrupt(enum gpio_signal signal)
{
const struct gpio_info *g = gpio_list + signal;
uint32_t bit;
/* Fail if not implemented or no interrupt handler */
if (!g->mask || signal >= GPIO_IH_COUNT)
return EC_ERROR_INVAL;
STM32_EXTI_IMR &= ~g->mask;
bit = GPIO_MASK_TO_NUM(g->mask);
exti_events[bit] = 0;
return EC_SUCCESS;
}
int gpio_clear_pending_interrupt(enum gpio_signal signal)
{
const struct gpio_info *g = gpio_list + signal;
if (!g->mask || signal >= GPIO_IH_COUNT)
return EC_ERROR_INVAL;
STM32_EXTI_PR |= g->mask;
return EC_SUCCESS;
}
/*****************************************************************************/
/* Interrupt handler */
void __keep gpio_interrupt(void)
{
int bit;
/* process only GPIO EXTINTs (EXTINT0..15) not other EXTINTs */
uint32_t pending = STM32_EXTI_PR & 0xFFFF;
uint8_t signal;
STM32_EXTI_PR = pending;
while (pending) {
bit = get_next_bit(&pending);
signal = exti_events[bit];
if (signal < GPIO_IH_COUNT)
gpio_irq_handlers[signal](signal);
}
}
#ifdef CHIP_FAMILY_STM32F0
DECLARE_IRQ(STM32_IRQ_EXTI0_1, gpio_interrupt, STM32_IRQ_EXT0_1_PRIORITY);
DECLARE_IRQ(STM32_IRQ_EXTI2_3, gpio_interrupt, STM32_IRQ_EXT2_3_PRIORITY);
DECLARE_IRQ(STM32_IRQ_EXTI4_15, gpio_interrupt, STM32_IRQ_EXTI4_15_PRIORITY);
#endif