u-boot/drivers/serial/serial_pxa.c
Wolfgang Denk 1a4596601f Add GPL-2.0+ SPDX-License-Identifier to source files
Signed-off-by: Wolfgang Denk <wd@denx.de>
[trini: Fixup common/cmd_io.c]
Signed-off-by: Tom Rini <trini@ti.com>
2013-07-24 09:44:38 -04:00

300 lines
6.6 KiB
C

/*
* Copyright (C) 2011 Marek Vasut <marek.vasut@gmail.com>
*
* (C) Copyright 2002
* Wolfgang Denk, DENX Software Engineering, <wd@denx.de>
*
* (C) Copyright 2002
* Sysgo Real-Time Solutions, GmbH <www.elinos.com>
* Marius Groeger <mgroeger@sysgo.de>
*
* (C) Copyright 2002
* Sysgo Real-Time Solutions, GmbH <www.elinos.com>
* Alex Zuepke <azu@sysgo.de>
*
* Copyright (C) 1999 2000 2001 Erik Mouw (J.A.K.Mouw@its.tudelft.nl)
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <watchdog.h>
#include <serial.h>
#include <asm/arch/pxa-regs.h>
#include <asm/arch/regs-uart.h>
#include <asm/io.h>
#include <linux/compiler.h>
DECLARE_GLOBAL_DATA_PTR;
/*
* The numbering scheme differs here for PXA25x, PXA27x and PXA3xx so we can
* easily handle enabling of clock.
*/
#ifdef CONFIG_CPU_MONAHANS
#define UART_CLK_BASE CKENA_21_BTUART
#define UART_CLK_REG CKENA
#define BTUART_INDEX 0
#define FFUART_INDEX 1
#define STUART_INDEX 2
#elif CONFIG_CPU_PXA25X
#define UART_CLK_BASE (1 << 4) /* HWUART */
#define UART_CLK_REG CKEN
#define HWUART_INDEX 0
#define STUART_INDEX 1
#define FFUART_INDEX 2
#define BTUART_INDEX 3
#else /* PXA27x */
#define UART_CLK_BASE CKEN5_STUART
#define UART_CLK_REG CKEN
#define STUART_INDEX 0
#define FFUART_INDEX 1
#define BTUART_INDEX 2
#endif
/*
* Only PXA250 has HWUART, to avoid poluting the code with more macros,
* artificially introduce this.
*/
#ifndef CONFIG_CPU_PXA25X
#define HWUART_INDEX 0xff
#endif
static uint32_t pxa_uart_get_baud_divider(void)
{
if (gd->baudrate == 1200)
return 768;
else if (gd->baudrate == 9600)
return 96;
else if (gd->baudrate == 19200)
return 48;
else if (gd->baudrate == 38400)
return 24;
else if (gd->baudrate == 57600)
return 16;
else if (gd->baudrate == 115200)
return 8;
else /* Unsupported baudrate */
return 0;
}
static struct pxa_uart_regs *pxa_uart_index_to_regs(uint32_t uart_index)
{
switch (uart_index) {
case FFUART_INDEX: return (struct pxa_uart_regs *)FFUART_BASE;
case BTUART_INDEX: return (struct pxa_uart_regs *)BTUART_BASE;
case STUART_INDEX: return (struct pxa_uart_regs *)STUART_BASE;
case HWUART_INDEX: return (struct pxa_uart_regs *)HWUART_BASE;
default:
return NULL;
}
}
static void pxa_uart_toggle_clock(uint32_t uart_index, int enable)
{
uint32_t clk_reg, clk_offset, reg;
clk_reg = UART_CLK_REG;
clk_offset = UART_CLK_BASE << uart_index;
reg = readl(clk_reg);
if (enable)
reg |= clk_offset;
else
reg &= ~clk_offset;
writel(reg, clk_reg);
}
/*
* Enable clock and set baud rate, parity etc.
*/
void pxa_setbrg_dev(uint32_t uart_index)
{
uint32_t divider = 0;
struct pxa_uart_regs *uart_regs;
divider = pxa_uart_get_baud_divider();
if (!divider)
hang();
uart_regs = pxa_uart_index_to_regs(uart_index);
if (!uart_regs)
hang();
pxa_uart_toggle_clock(uart_index, 1);
/* Disable interrupts and FIFOs */
writel(0, &uart_regs->ier);
writel(0, &uart_regs->fcr);
/* Set baud rate */
writel(LCR_WLS0 | LCR_WLS1 | LCR_DLAB, &uart_regs->lcr);
writel(divider & 0xff, &uart_regs->dll);
writel(divider >> 8, &uart_regs->dlh);
writel(LCR_WLS0 | LCR_WLS1, &uart_regs->lcr);
/* Enable UART */
writel(IER_UUE, &uart_regs->ier);
}
/*
* Initialise the serial port with the given baudrate. The settings
* are always 8 data bits, no parity, 1 stop bit, no start bits.
*/
int pxa_init_dev(unsigned int uart_index)
{
pxa_setbrg_dev (uart_index);
return 0;
}
/*
* Output a single byte to the serial port.
*/
void pxa_putc_dev(unsigned int uart_index, const char c)
{
struct pxa_uart_regs *uart_regs;
uart_regs = pxa_uart_index_to_regs(uart_index);
if (!uart_regs)
hang();
while (!(readl(&uart_regs->lsr) & LSR_TEMT))
WATCHDOG_RESET();
writel(c, &uart_regs->thr);
/* If \n, also do \r */
if (c == '\n')
pxa_putc_dev (uart_index,'\r');
}
/*
* Read a single byte from the serial port. Returns 1 on success, 0
* otherwise. When the function is succesfull, the character read is
* written into its argument c.
*/
int pxa_tstc_dev(unsigned int uart_index)
{
struct pxa_uart_regs *uart_regs;
uart_regs = pxa_uart_index_to_regs(uart_index);
if (!uart_regs)
return -1;
return readl(&uart_regs->lsr) & LSR_DR;
}
/*
* Read a single byte from the serial port. Returns 1 on success, 0
* otherwise. When the function is succesfull, the character read is
* written into its argument c.
*/
int pxa_getc_dev(unsigned int uart_index)
{
struct pxa_uart_regs *uart_regs;
uart_regs = pxa_uart_index_to_regs(uart_index);
if (!uart_regs)
return -1;
while (!(readl(&uart_regs->lsr) & LSR_DR))
WATCHDOG_RESET();
return readl(&uart_regs->rbr) & 0xff;
}
void pxa_puts_dev(unsigned int uart_index, const char *s)
{
while (*s)
pxa_putc_dev(uart_index, *s++);
}
#define pxa_uart(uart, UART) \
int uart##_init(void) \
{ \
return pxa_init_dev(UART##_INDEX); \
} \
\
void uart##_setbrg(void) \
{ \
return pxa_setbrg_dev(UART##_INDEX); \
} \
\
void uart##_putc(const char c) \
{ \
return pxa_putc_dev(UART##_INDEX, c); \
} \
\
void uart##_puts(const char *s) \
{ \
return pxa_puts_dev(UART##_INDEX, s); \
} \
\
int uart##_getc(void) \
{ \
return pxa_getc_dev(UART##_INDEX); \
} \
\
int uart##_tstc(void) \
{ \
return pxa_tstc_dev(UART##_INDEX); \
} \
#define pxa_uart_desc(uart) \
struct serial_device serial_##uart##_device = \
{ \
.name = "serial_"#uart, \
.start = uart##_init, \
.stop = NULL, \
.setbrg = uart##_setbrg, \
.getc = uart##_getc, \
.tstc = uart##_tstc, \
.putc = uart##_putc, \
.puts = uart##_puts, \
};
#define pxa_uart_multi(uart, UART) \
pxa_uart(uart, UART) \
pxa_uart_desc(uart)
#if defined(CONFIG_HWUART)
pxa_uart_multi(hwuart, HWUART)
#endif
#if defined(CONFIG_STUART)
pxa_uart_multi(stuart, STUART)
#endif
#if defined(CONFIG_FFUART)
pxa_uart_multi(ffuart, FFUART)
#endif
#if defined(CONFIG_BTUART)
pxa_uart_multi(btuart, BTUART)
#endif
__weak struct serial_device *default_serial_console(void)
{
#if CONFIG_CONS_INDEX == 1
return &serial_hwuart_device;
#elif CONFIG_CONS_INDEX == 2
return &serial_stuart_device;
#elif CONFIG_CONS_INDEX == 3
return &serial_ffuart_device;
#elif CONFIG_CONS_INDEX == 4
return &serial_btuart_device;
#else
#error "Bad CONFIG_CONS_INDEX."
#endif
}
void pxa_serial_initialize(void)
{
#if defined(CONFIG_FFUART)
serial_register(&serial_ffuart_device);
#endif
#if defined(CONFIG_BTUART)
serial_register(&serial_btuart_device);
#endif
#if defined(CONFIG_STUART)
serial_register(&serial_stuart_device);
#endif
}