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de880632fc
With printch() the console messages are sent out one character at a time which is agonizingly slow especially with semihosting as the whole trap intercept, remote byte access, and system resume danse is performed for every single character across a relatively slow remote debug connection. Let's use printascii() to send a whole string at once. This is also going to be more efficient, albeit to a quite lesser extent, with serial ports as well. Signed-off-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
51 lines
1.1 KiB
C
51 lines
1.1 KiB
C
/*
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* linux/arch/arm/kernel/early_printk.c
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*
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* Copyright (C) 2009 Sascha Hauer <s.hauer@pengutronix.de>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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#include <linux/kernel.h>
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#include <linux/console.h>
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#include <linux/init.h>
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#include <linux/string.h>
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extern void printascii(const char *);
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static void early_write(const char *s, unsigned n)
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{
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char buf[128];
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while (n) {
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unsigned l = min(n, sizeof(buf)-1);
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memcpy(buf, s, l);
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buf[l] = 0;
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s += l;
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n -= l;
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printascii(buf);
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}
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}
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static void early_console_write(struct console *con, const char *s, unsigned n)
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{
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early_write(s, n);
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}
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static struct console early_console_dev = {
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.name = "earlycon",
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.write = early_console_write,
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.flags = CON_PRINTBUFFER | CON_BOOT,
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.index = -1,
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};
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static int __init setup_early_printk(char *buf)
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{
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early_console = &early_console_dev;
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register_console(&early_console_dev);
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return 0;
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}
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early_param("earlyprintk", setup_early_printk);
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