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// SPDX-License-Identifier: GPL-2.0-or-later
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/*
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 *  RouterBoard 500 specific prom routines
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 *
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 *  Copyright (C) 2003, Peter Sadik <[email protected]>
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 *  Copyright (C) 2005-2006, P.Christeas <[email protected]>
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 *  Copyright (C) 2007, Gabor Juhos <[email protected]>
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 *			Felix Fietkau <[email protected]>
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 *			Florian Fainelli <[email protected]>
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 */
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#include <linux/init.h>
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#include <linux/mm.h>
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#include <linux/export.h>
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#include <linux/string.h>
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#include <linux/console.h>
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#include <linux/memblock.h>
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#include <linux/ioport.h>
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#include <asm/bootinfo.h>
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#include <asm/mach-rc32434/ddr.h>
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#include <asm/mach-rc32434/prom.h>
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unsigned int idt_cpu_freq = 132000000;
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EXPORT_SYMBOL(idt_cpu_freq);
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static struct resource ddr_reg[] = {
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	{
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		.name = "ddr-reg",
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		.start = DDR0_PHYS_ADDR,
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		.end = DDR0_PHYS_ADDR + sizeof(struct ddr_ram),
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		.flags = IORESOURCE_MEM,
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	}
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};
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static inline int match_tag(char *arg, const char *tag)
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{
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	return strncmp(arg, tag, strlen(tag)) == 0;
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}
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static inline unsigned long tag2ul(char *arg, const char *tag)
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{
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	char *num;
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	num = arg + strlen(tag);
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	return simple_strtoul(num, 0, 10);
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}
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static void __init prom_setup_cmdline(void)
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{
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	static char cmd_line[COMMAND_LINE_SIZE] __initdata;
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	char *cp, *board;
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	int prom_argc;
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	char **prom_argv;
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	int i;
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	size_t len;
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	prom_argc = fw_arg0;
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	prom_argv = (char **) fw_arg1;
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	cp = cmd_line;
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		/* Note: it is common that parameters start
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		 * at argv[1] and not argv[0],
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		 * however, our elf loader starts at [0] */
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	for (i = 0; i < prom_argc; i++) {
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		if (match_tag(prom_argv[i], FREQ_TAG)) {
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			idt_cpu_freq = tag2ul(prom_argv[i], FREQ_TAG);
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			continue;
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		}
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#ifdef IGNORE_CMDLINE_MEM
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		/* parses out the "mem=xx" arg */
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		if (match_tag(prom_argv[i], MEM_TAG))
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			continue;
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#endif
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		if (i > 0)
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			*(cp++) = ' ';
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		if (match_tag(prom_argv[i], BOARD_TAG)) {
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			board = prom_argv[i] + strlen(BOARD_TAG);
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			if (match_tag(board, BOARD_RB532A))
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				mips_machtype = MACH_MIKROTIK_RB532A;
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			else
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				mips_machtype = MACH_MIKROTIK_RB532;
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		}
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		len = strlen(prom_argv[i]);
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		memcpy(cp, prom_argv[i], len + 1);
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		cp += len;
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	}
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	*(cp++) = ' ';
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	len = strlen(arcs_cmdline);
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	if (len > 0) {
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		*(cp++) = ' ';
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		memcpy(cp, arcs_cmdline, len + 1);
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		cp += len;
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	}
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	cmd_line[COMMAND_LINE_SIZE - 1] = '\0';
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	strscpy(arcs_cmdline, cmd_line);
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}
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void __init prom_init(void)
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{
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	struct ddr_ram __iomem *ddr;
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	phys_addr_t memsize;
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	phys_addr_t ddrbase;
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	ddr = ioremap(ddr_reg[0].start,
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			ddr_reg[0].end - ddr_reg[0].start);
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	if (!ddr) {
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		printk(KERN_ERR "Unable to remap DDR register\n");
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		return;
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	}
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	ddrbase = (phys_addr_t)&ddr->ddrbase;
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	memsize = (phys_addr_t)&ddr->ddrmask;
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	memsize = 0 - memsize;
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	prom_setup_cmdline();
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	/* give all RAM to boot allocator,
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	 * except for the first 0x400 and the last 0x200 bytes */
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	memblock_add(ddrbase + 0x400, memsize - 0x600);
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}
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