diff options
Diffstat (limited to 'chip/mec1322/uart.c')
-rw-r--r-- | chip/mec1322/uart.c | 219 |
1 files changed, 0 insertions, 219 deletions
diff --git a/chip/mec1322/uart.c b/chip/mec1322/uart.c deleted file mode 100644 index a913cf36ab..0000000000 --- a/chip/mec1322/uart.c +++ /dev/null @@ -1,219 +0,0 @@ -/* Copyright 2013 The ChromiumOS Authors - * Use of this source code is governed by a BSD-style license that can be - * found in the LICENSE file. - */ - -/* UART module for MEC1322 */ - -#include "clock.h" -#include "common.h" -#include "console.h" -#include "gpio.h" -#include "lpc.h" -#include "registers.h" -#include "system.h" -#include "task.h" -#include "uart.h" -#include "util.h" - -#define TX_FIFO_SIZE 16 - -static int init_done; -static int tx_fifo_used; - -int uart_init_done(void) -{ - return init_done; -} - -void uart_tx_start(void) -{ - /* If interrupt is already enabled, nothing to do */ - if (MEC1322_UART_IER & BIT(1)) - return; - - /* Do not allow deep sleep while transmit in progress */ - disable_sleep(SLEEP_MASK_UART); - - /* - * Re-enable the transmit interrupt, then forcibly trigger the - * interrupt. This works around a hardware problem with the - * UART where the FIFO only triggers the interrupt when its - * threshold is _crossed_, not just met. - */ - MEC1322_UART_IER |= BIT(1); - task_trigger_irq(MEC1322_IRQ_UART); -} - -void uart_tx_stop(void) -{ - MEC1322_UART_IER &= ~BIT(1); - - /* Re-allow deep sleep */ - enable_sleep(SLEEP_MASK_UART); -} - -void uart_tx_flush(void) -{ - /* Wait for transmit FIFO empty */ - while (!(MEC1322_UART_LSR & MEC1322_LSR_TX_EMPTY)) - ; -} - -int uart_tx_ready(void) -{ - /* - * We have no indication of free space in transmit FIFO. To work around - * this, we check transmit FIFO empty bit every 16 characters written. - */ - return tx_fifo_used != 0 || (MEC1322_UART_LSR & MEC1322_LSR_TX_EMPTY); -} - -int uart_tx_in_progress(void) -{ - /* return 0: FIFO is empty, 1: FIFO NOT Empty */ - return !(MEC1322_UART_LSR & MEC1322_LSR_TX_EMPTY); -} - -int uart_rx_available(void) -{ - return MEC1322_UART_LSR & BIT(0); -} - -void uart_write_char(char c) -{ - /* Wait for space in transmit FIFO. */ - while (!uart_tx_ready()) - ; - - tx_fifo_used = (tx_fifo_used + 1) % TX_FIFO_SIZE; - MEC1322_UART_TB = c; -} - -int uart_read_char(void) -{ - return MEC1322_UART_RB; -} - -static void uart_clear_rx_fifo(int channel) -{ - MEC1322_UART_FCR = BIT(0) | BIT(1); -} - -/** - * Interrupt handler for UART - */ -static void uart_ec_interrupt(void) -{ - /* Read input FIFO until empty, then fill output FIFO */ - uart_process_input(); - uart_process_output(); -} -DECLARE_IRQ(MEC1322_IRQ_UART, uart_ec_interrupt, 1); - -void uart_init(void) -{ - /* Set UART to reset on VCC1_RESET instaed of nSIO_RESET */ - MEC1322_UART_CFG &= ~BIT(1); - - /* Baud rate = 115200. 1.8432MHz clock. Divisor = 1 */ - - /* Set CLK_SRC = 0 */ - MEC1322_UART_CFG &= ~BIT(0); - - /* Set DLAB = 1 */ - MEC1322_UART_LCR |= BIT(7); - - /* PBRG0/PBRG1 */ - MEC1322_UART_PBRG0 = 1; - MEC1322_UART_PBRG1 = 0; - - /* Set DLAB = 0 */ - MEC1322_UART_LCR &= ~BIT(7); - - /* Set word length to 8-bit */ - MEC1322_UART_LCR |= BIT(0) | BIT(1); - - /* Enable FIFO */ - MEC1322_UART_FCR = BIT(0); - - /* Activate UART */ - MEC1322_UART_ACT |= BIT(0); - - /* - clock_enable_peripheral(CGC_OFFSET_UART, mask, - CGC_MODE_RUN | CGC_MODE_SLEEP);*/ - - gpio_config_module(MODULE_UART, 1); - - /* - * Enable interrupts for UART0. - */ - uart_clear_rx_fifo(0); - MEC1322_UART_IER |= BIT(0); - MEC1322_UART_MCR |= BIT(3); - MEC1322_INT_ENABLE(15) |= BIT(0); - MEC1322_INT_BLK_EN |= BIT(15); - task_enable_irq(MEC1322_IRQ_UART); - - init_done = 1; -} - -#ifdef CONFIG_LOW_POWER_IDLE -void uart_enter_dsleep(void) -{ - /* Disable the UART interrupt. */ - task_disable_irq(MEC1322_IRQ_UART); /* NVIC interrupt for UART=13 */ - - /* - * Set the UART0 RX pin to be a GPIO-162(fixed pin) interrupt - * with the flags defined in the gpio.inc file. - */ - gpio_reset(GPIO_UART0_RX); - - /* power-down/de-activate UART0 */ - MEC1322_UART_ACT &= ~BIT(0); - - /* Clear pending interrupts on GPIO_UART0_RX(GPIO162, girq=8, bit=18) */ - MEC1322_INT_SOURCE(8) = (1 << 18); - - /* Enable GPIO interrupts on the UART0 RX pin. */ - gpio_enable_interrupt(GPIO_UART0_RX); -} - -void uart_exit_dsleep(void) -{ - /* - * If the UART0 RX GPIO interrupt has not fired, then no edge has been - * detected. Disable the GPIO interrupt so that switching the pin over - * to a UART pin doesn't inadvertently cause a GPIO edge interrupt. - * Note: we can't disable this interrupt if it has already fired - * because then the IRQ will not run at all. - */ - if (!(BIT(18) & MEC1322_INT_SOURCE(8))) /* if edge interrupt */ - gpio_disable_interrupt(GPIO_UART0_RX); - - /* Configure UART0 pins for use in UART peripheral. */ - gpio_config_module(MODULE_UART, 1); - - /* Clear pending interrupts on UART peripheral and enable interrupts. */ - uart_clear_rx_fifo(0); - task_enable_irq(MEC1322_IRQ_UART); /* NVIC interrupt for UART = 13 */ - - /* power-up/activate UART0 */ - MEC1322_UART_ACT |= BIT(0); -} - -void uart_deepsleep_interrupt(enum gpio_signal signal) -{ - /* - * Activity seen on UART RX pin while UART was disabled for deep sleep. - * The console won't see that character because the UART is disabled, - * so we need to inform the clock module of UART activity ourselves. - */ - clock_refresh_console_in_use(); - - /* Disable interrupts on UART0 RX pin to avoid repeated interrupts. */ - gpio_disable_interrupt(GPIO_UART0_RX); -} -#endif /* CONFIG_LOW_POWER_IDLE */ |