linux/arch/s390/boot/alternative.c

// SPDX-License-Identifier: GPL-2.0
#define boot_fmt(fmt)	"alt: " fmt
#include "boot.h"

#define a_debug		boot_debug

#include "../kernel/alternative.c"

static void alt_debug_all(int type)
{
	int i;

	switch (type) {
	case ALT_TYPE_FACILITY:
		for (i = 0; i < ARRAY_SIZE(alt_debug.facilities); i++)
			alt_debug.facilities[i] = -1UL;
		break;
	case ALT_TYPE_FEATURE:
		for (i = 0; i < ARRAY_SIZE(alt_debug.mfeatures); i++)
			alt_debug.mfeatures[i] = -1UL;
		break;
	case ALT_TYPE_SPEC:
		alt_debug.spec = 1;
		break;
	}
}

static void alt_debug_modify(int type, unsigned int nr, bool clear)
{
	switch (type) {
	case ALT_TYPE_FACILITY:
		if (clear)
			__clear_facility(nr, alt_debug.facilities);
		else
			__set_facility(nr, alt_debug.facilities);
		break;
	case ALT_TYPE_FEATURE:
		if (clear)
			__clear_machine_feature(nr, alt_debug.mfeatures);
		else
			__set_machine_feature(nr, alt_debug.mfeatures);
		break;
	}
}

static char *alt_debug_parse(int type, char *str)
{
	unsigned long val, endval;
	char *endp;
	bool clear;
	int i;

	if (*str == ':') {
		str++;
	} else {
		alt_debug_all(type);
		return str;
	}
	clear = false;
	if (*str == '!') {
		alt_debug_all(type);
		clear = true;
		str++;
	}
	while (*str) {
		val = simple_strtoull(str, &endp, 0);
		if (str == endp)
			break;
		str = endp;
		if (*str == '-') {
			str++;
			endval = simple_strtoull(str, &endp, 0);
			if (str == endp)
				break;
			str = endp;
			while (val <= endval) {
				alt_debug_modify(type, val, clear);
				val++;
			}
		} else {
			alt_debug_modify(type, val, clear);
		}
		if (*str != ',')
			break;
		str++;
	}
	return str;
}

/*
 * Use debug-alternative command line parameter for debugging:
 * "debug-alternative"
 *  -> print debug message for every single alternative
 *
 * "debug-alternative=0;2"
 * -> print debug message for all alternatives with type 0 and 2
 *
 * "debug-alternative=0:0-7"
 * -> print debug message for all alternatives with type 0 and with
 *    facility numbers within the range of 0-7
 *    (if type 0 is ALT_TYPE_FACILITY)
 *
 * "debug-alternative=0:!8;1"
 * -> print debug message for all alternatives with type 0, for all
 *    facility number, except facility 8, and in addition print all
 *    alternatives with type 1
 */
void alt_debug_setup(char *str)
{
	unsigned long type;
	char *endp;
	int i;

	if (!str) {
		alt_debug_all(ALT_TYPE_FACILITY);
		alt_debug_all(ALT_TYPE_FEATURE);
		alt_debug_all(ALT_TYPE_SPEC);
		return;
	}
	while (*str) {
		type = simple_strtoull(str, &endp, 0);
		if (str == endp)
			break;
		str = endp;
		switch (type) {
		case ALT_TYPE_FACILITY:
		case ALT_TYPE_FEATURE:
			str = alt_debug_parse(type, str);
			break;
		case ALT_TYPE_SPEC:
			alt_debug_all(ALT_TYPE_SPEC);
			break;
		}
		if (*str != ';')
			break;
		str++;
	}
}