zephyr/drivers/console/xtensa_sim_console.c

81 lines
1.8 KiB
C

/*
* Copyright (c) 2016 Cadence Design Systems, Inc.
* SPDX-License-Identifier: Apache-2.0
*/
#include <xtensa/simcall.h>
#include <device.h>
#include <init.h>
#if defined(CONFIG_PRINTK) || defined(CONFIG_STDOUT_CONSOLE)
/**
* @brief Output one character to SIMULATOR console
* @param c Character to output
* @return The character passed as input.
*/
static int console_out(int c)
{
char buf[16];
register int a2 __asm__ ("a2") = SYS_write;
register int a3 __asm__ ("a3") = 1;
register char *a4 __asm__ ("a4") = buf;
register int a5 __asm__ ("a5") = 1;
register int ret_val __asm__ ("a2");
register int ret_err __asm__ ("a3");
buf[0] = (char)c;
__asm__ volatile ("simcall"
: "=a" (ret_val), "=a" (ret_err)
: "a" (a2), "a" (a3), "a" (a4), "a" (a5)
: "memory");
return c;
}
#endif
#if defined(CONFIG_STDOUT_CONSOLE)
extern void __stdout_hook_install(int (*hook)(int));
#else
#define __stdout_hook_install(x) \
do {/* nothing */ \
} while ((0))
#endif
#if defined(CONFIG_PRINTK)
extern void __printk_hook_install(int (*fn)(int));
#else
#define __printk_hook_install(x) \
do {/* nothing */ \
} while ((0))
#endif
/**
* @brief Install printk/stdout hook for Xtensa Simulator console output
* @return N/A
*/
static void xt_sim_console_hook_install(void)
{
__stdout_hook_install(console_out);
__printk_hook_install(console_out);
}
/**
* @brief Initialize the console/debug port
* @return 0 if successful, otherwise failed.
*/
static int xt_sim_console_init(struct device *arg)
{
ARG_UNUSED(arg);
xt_sim_console_hook_install();
return 0;
}
/* UART consloe initializes after the UART device itself */
SYS_INIT(xt_sim_console_init,
#if defined(CONFIG_EARLY_CONSOLE)
PRE_KERNEL_1,
#else
POST_KERNEL,
#endif
CONFIG_XTENSA_CONSOLE_INIT_PRIORITY);