aos/kernel/arch/arm/rpi3_miniuart.c
Daniel Schwyn 6d444bf552 Main handout
Signed-off-by: Daniel Schwyn <daniel.schwyn@inf.ethz.ch>
2022-03-03 14:57:51 +01:00

119 lines
3.7 KiB
C

/**
* \file
* \brief ARM pl011 UART kernel-level driver.
*/
/*
* Copyright (c) 2007, 2008, ETH Zurich.
* All rights reserved.
*
* This file is distributed under the terms in the attached LICENSE file.
* If you do not find this file, copies can be found by writing to:
* ETH Zurich D-INFK, Universitaetstrasse 6, CH-8092 Zurich. Attn: Systems Group.
*/
#include <arch/arm/rpi3_miniuart.h>
#include <kernel.h>
#include <paging_kernel_arch.h>
#include <arch/arm/arm.h>
#include <arch/arm/platform.h>
#include <serial.h>
#include <dev/rpi3_miniuart_dev.h>
static rpi3_miniuart_t uart;
#define MSG(format, ...) printk( LOG_NOTE, "rpi3_miniuart: "format, ## __VA_ARGS__ )
/*
* \brief Initialize a serial port. The MMU is turned on.
*/
void rpi3_miniuart_init(lvaddr_t base, bool hwinit)
{
// assert(paging_mmu_enabled());
// assert(port < serial_num_physical_ports);
//
// pl011_uart_t *u = &uarts[port];
//
// // [Re]initialize the Mackerel state for the UART
rpi3_miniuart_initialize(&uart, (mackerel_addr_t) base);
//
// if (hwinit) {
// // Mask all interrupts: set all bits to zero
// pl011_uart_IMSC_rawwr(u, INTERRUPTS_MASK);
//
// // Disable the UART before reconfiguring it.
// pl011_uart_CR_uarten_wrf(u, 0);
//
// // Clear and enable the receive interrupt.
// pl011_uart_ICR_rxic_wrf(u, 1);
// pl011_uart_IMSC_rxim_wrf(u, 1);
//
// // Configure port to 38400 baud, 8 data, no parity, 1 stop (8-N-1)
// //
// // (This is a mild scam as system is running in QEMU)
// //
// // Note baud rate changes not committed in h/w until lcr_h
// // written.
// pl011_uart_IBRD_divint_wrf(u, 0xc); // Assuming UARTCLK is 7.3728MHz
// pl011_uart_FBRD_divfrac_wrf(u, 0);
//
// /* Configure the line control register. */
// pl011_uart_LCR_H_t lcr= (pl011_uart_LCR_H_t)0;
// /* Disable FIFOs. There's no way to get an interrupt when a single
// * character arrives with FIFOs, so it's useless as a console. */
// lcr= pl011_uart_LCR_H_fen_insert(lcr, 0);
// /* Eight data bits. */
// lcr= pl011_uart_LCR_H_wlen_insert(lcr, pl011_uart_bits8);
// /* No parity. */
// lcr= pl011_uart_LCR_H_pen_insert(lcr, 0);
// /* One stop bit. */
// lcr= pl011_uart_LCR_H_stp2_insert(lcr, 0);
// pl011_uart_LCR_H_wr(u, lcr);
//
// /* Configure the main control register. */
// pl011_uart_CR_t cr = (pl011_uart_CR_t)0;
// /* No flow control. */
// cr= pl011_uart_CR_ctsen_insert(cr, 0);
// cr= pl011_uart_CR_rtsen_insert(cr, 0);
// /* Enable transmit and receive. */
// cr= pl011_uart_CR_txe_insert(cr, 1);
// cr= pl011_uart_CR_rxe_insert(cr, 1);
// /* Enable UART. */
// cr= pl011_uart_CR_uarten_insert(cr, 1);
// pl011_uart_CR_wr(u, cr);
// }
}
/*
* \brief Put a character to the port
*/
void serial_putchar(unsigned port, char c)
{
while(rpi3_miniuart_STAT_txff_rdf(&uart) == 1) ;
rpi3_miniuart_DR_rawwr(&uart, c);
// assert(port < MAX_PORTS);
// pl011_uart_t *u = &uarts[port];
// assert(u->base != 0);
//
// while(pl011_uart_FR_txff_rdf(u) == 1) ;
// pl011_uart_DR_rawwr(u, c);
}
/*
* \brief Read a character from a port
*/
char serial_getchar(unsigned port)
{
// assert(port < MAX_PORTS);
// pl011_uart_t *u = &uarts[port];
// assert(u->base != 0);
//
// /* Wait for data. */
// while(pl011_uart_FR_rxfe_rdf(u) == 1);
//
// /* Acknowledge any interrupt. */
// pl011_uart_ICR_rxic_wrf(u, 1);
//
// return (char)pl011_uart_DR_data_rdf(u);
return 0;
}