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Diffstat (limited to 'chip/mt_scp/rv32i_common/uart.c')
-rw-r--r--chip/mt_scp/rv32i_common/uart.c161
1 files changed, 0 insertions, 161 deletions
diff --git a/chip/mt_scp/rv32i_common/uart.c b/chip/mt_scp/rv32i_common/uart.c
deleted file mode 100644
index 35b4003c9f..0000000000
--- a/chip/mt_scp/rv32i_common/uart.c
+++ /dev/null
@@ -1,161 +0,0 @@
-/* Copyright 2020 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.
- */
-
-/* SCP UART module */
-
-#include "csr.h"
-#include "system.h"
-#include "uart.h"
-#include "uart_regs.h"
-#include "util.h"
-
-/*
- * UARTN == 0, SCP UART0
- * UARTN == 1, SCP UART1
- * UARTN == 2, AP UART1
- */
-#define UARTN CONFIG_UART_CONSOLE
-#define UART_IDLE_WAIT_US 500
-#define UART_INTC_GROUP 12
-
-static uint8_t init_done, tx_started;
-
-void uart_init(void)
-{
- const uint32_t baud_rate = CONFIG_UART_BAUD_RATE;
- const uint32_t uart_clock = 26000000;
- const uint32_t div = DIV_ROUND_NEAREST(uart_clock, baud_rate * 16);
-
- uart_init_pinmux();
-
- /* Clear FIFO */
- UART_FCR(UARTN) = UART_FCR_ENABLE_FIFO
- | UART_FCR_CLEAR_RCVR
- | UART_FCR_CLEAR_XMIT;
- /* Line control: parity none, 8 bit, 1 stop bit */
- UART_LCR(UARTN) = UART_LCR_WLEN8;
- /* For baud rate <= 115200 */
- UART_HIGHSPEED(UARTN) = 0;
-
- /* DLAB start */
- UART_LCR(UARTN) |= UART_LCR_DLAB;
- UART_DLL(UARTN) = div & 0xff;
- UART_DLH(UARTN) = (div >> 8) & 0xff;
- UART_LCR(UARTN) &= ~UART_LCR_DLAB;
- /* DLAB end */
-
- /* Enable received data interrupt */
- UART_IER(UARTN) |= UART_IER_RDI;
-
-#if (UARTN < SCP_UART_COUNT)
- task_enable_irq(UART_TX_IRQ(UARTN));
- task_enable_irq(UART_RX_IRQ(UARTN));
-#endif
-
- init_done = 1;
-}
-
-int uart_init_done(void)
-{
- return init_done;
-}
-
-void uart_tx_flush(void)
-{
- while (!(UART_LSR(UARTN) & UART_LSR_TEMT))
- ;
-}
-
-int uart_tx_ready(void)
-{
- return UART_LSR(UARTN) & UART_LSR_THRE;
-}
-
-int uart_rx_available(void)
-{
- return UART_LSR(UARTN) & UART_LSR_DR;
-}
-
-void uart_write_char(char c)
-{
- while (!uart_tx_ready())
- ;
-
- UART_THR(UARTN) = c;
-}
-
-int uart_read_char(void)
-{
- return UART_RBR(UARTN);
-}
-
-void uart_tx_start(void)
-{
- tx_started = 1;
- if (UART_IER(UARTN) & UART_IER_THRI)
- return;
- disable_sleep(SLEEP_MASK_UART);
- UART_IER(UARTN) |= UART_IER_THRI;
-}
-
-void uart_tx_stop(void)
-{
- /*
- * Workaround for b/157541273.
- * Don't unset the THRI flag unless we are in the UART ISR.
- *
- * Note:
- * MICAUSE denotes current INTC group number.
- */
- if (in_interrupt_context() &&
- read_csr(CSR_VIC_MICAUSE) != UART_INTC_GROUP)
- return;
-
- tx_started = 0;
- UART_IER(UARTN) &= ~UART_IER_THRI;
- enable_sleep(SLEEP_MASK_UART);
-}
-
-static void uart_process(void)
-{
- uart_process_input();
- uart_process_output();
-}
-
-#if (UARTN < SCP_UART_COUNT)
-static void uart_irq_handler(void)
-{
- extern volatile int ec_int;
-
- switch (ec_int) {
- case UART_TX_IRQ(UARTN):
- uart_process();
- task_clear_pending_irq(ec_int);
- break;
- case UART_RX_IRQ(UARTN):
- uart_process();
- SCP_CORE0_INTC_UART_RX_IRQ(UARTN) = BIT(0);
- asm volatile ("fence.i" ::: "memory");
- task_clear_pending_irq(ec_int);
- break;
- }
-}
-DECLARE_IRQ(UART_INTC_GROUP, uart_irq_handler, 0);
-#else
-
-#ifndef HAS_TASK_APUART
-#error "APUART task hasn't defined in ec.tasklist."
-#endif
-
-void uart_task(void)
-{
- while (1) {
- if (uart_rx_available() || tx_started)
- uart_process();
- else
- task_wait_event(UART_IDLE_WAIT_US);
- }
-}
-#endif