text: /*
   * This file is subject to the terms and conditions of the GNU General Public
   * License.  See the file "COPYING" in the main directory of this archive
   * for more details.
   *
   * PROM library functions for acquiring/using memory descriptors given to
   * us from the YAMON.
   *
   * Copyright (C) 1999,2000,2012  MIPS Technologies, Inc.
   * All rights reserved.
   * Authors: Carsten Langgaard <carstenl@mips.com>
   *          Steven J. Hill <sjhill@mips.com>
   */
  #include <linux/init.h>
  #include <linux/bootmem.h>
  #include <linux/string.h>
  
  #include <asm/bootinfo.h>
  #include <asm/cdmm.h>
  #include <asm/maar.h>
  #include <asm/sections.h>
  #include <asm/fw/fw.h>
  
  static fw_memblock_t mdesc[FW_MAX_MEMBLOCKS];
  
  /* determined physical memory size, not overridden by command line args	 */
  unsigned long physical_memsize = 0L;
  
  fw_memblock_t * __init fw_getmdesc(int eva)
  {
  	char *memsize_str, *ememsize_str = NULL, *ptr;
  	unsigned long memsize = 0, ememsize = 0;
  	static char cmdline[COMMAND_LINE_SIZE] __initdata;
  	int tmp;
  
  	/* otherwise look in the environment */
  
  	memsize_str = fw_getenv("memsize");
  	if (memsize_str) {
  		tmp = kstrtoul(memsize_str, 0, &memsize);
  		if (tmp)
  			pr_warn("Failed to read the 'memsize' env variable.\n");
  	}
  	if (eva) {
  	/* Look for ememsize for EVA */
  		ememsize_str = fw_getenv("ememsize");
  		if (ememsize_str) {
  			tmp = kstrtoul(ememsize_str, 0, &ememsize);
  			if (tmp)
  				pr_warn("Failed to read the 'ememsize' env variable.\n");
  		}
  	}
  	if (!memsize && !ememsize) {
  		pr_warn("memsize not set in YAMON, set to default (32Mb)\n");
  		physical_memsize = 0x02000000;
  	} else {
  		if (memsize > (256 << 20)) { /* memsize should be capped to 256M */
  			pr_warn("Unsupported memsize value (0x%lx) detected! "
  				"Using 0x10000000 (256M) instead\n",
  				memsize);
  			memsize = 256 << 20;
  		}
  		/* If ememsize is set, then set physical_memsize to that */
  		physical_memsize = ememsize ? : memsize;
  	}
  
  #ifdef CONFIG_CPU_BIG_ENDIAN
  	/* SOC-it swaps, or perhaps doesn't swap, when DMA'ing the last
  	   word of physical memory */
  	physical_memsize -= PAGE_SIZE;
  #endif
  
  	/* Check the command line for a memsize directive that overrides
  	   the physical/default amount */
  	strcpy(cmdline, arcs_cmdline);
  	ptr = strstr(cmdline, "memsize=");
  	if (ptr && (ptr != cmdline) && (*(ptr - 1) != ' '))
  		ptr = strstr(ptr, " memsize=");
  	/* And now look for ememsize */
  	if (eva) {
  		ptr = strstr(cmdline, "ememsize=");
  		if (ptr && (ptr != cmdline) && (*(ptr - 1) != ' '))
  			ptr = strstr(ptr, " ememsize=");
  	}
  
  	if (ptr)
  		memsize = memparse(ptr + 8 + (eva ? 1 : 0), &ptr);
  	else
  		memsize = physical_memsize;
  
  	/* Last 64K for HIGHMEM arithmetics */
  	if (memsize > 0x7fff0000)
  		memsize = 0x7fff0000;
  
  	memset(mdesc, 0, sizeof(mdesc));
  
  	mdesc[0].type = fw_dontuse;
  	mdesc[0].base = PHYS_OFFSET;
  	mdesc[0].size = 0x00001000;
  
  	mdesc[1].type = fw_code;
  	mdesc[1].base = mdesc[0].base + 0x00001000UL;
  	mdesc[1].size = 0x000ef000;
  
  	/*
  	 * The area 0x000f0000-0x000fffff is allocated for BIOS memory by the
  	 * south bridge and PCI access always forwarded to the ISA Bus and
  	 * BIOSCS# is always generated.
  	 * This mean that this area can't be used as DMA memory for PCI
  	 * devices.
  	 */
  	mdesc[2].type = fw_dontuse;
  	mdesc[2].base = mdesc[0].base + 0x000f0000UL;
  	mdesc[2].size = 0x00010000;
  
  	mdesc[3].type = fw_dontuse;
  	mdesc[3].base = mdesc[0].base + 0x00100000UL;
  	mdesc[3].size = CPHYSADDR(PFN_ALIGN((unsigned long)&_end)) -
  		0x00100000UL;
  
  	mdesc[4].type = fw_free;
  	mdesc[4].base = mdesc[0].base + CPHYSADDR(PFN_ALIGN(&_end));
  	mdesc[4].size = memsize - CPHYSADDR(mdesc[4].base);
  
  	return &mdesc[0];
  }
  
  static void free_init_pages_eva_malta(void *begin, void *end)
  {
  	free_init_pages("unused kernel", __pa_symbol((unsigned long *)begin),
  			__pa_symbol((unsigned long *)end));
  }
  
  static int __init fw_memtype_classify(unsigned int type)
  {
  	switch (type) {
  	case fw_free:
  		return BOOT_MEM_RAM;
  	case fw_code:
  		return BOOT_MEM_ROM_DATA;
  	default:
  		return BOOT_MEM_RESERVED;
  	}
  }
  
  void __init fw_meminit(void)
  {
  	fw_memblock_t *p;
  
  	p = fw_getmdesc(config_enabled(CONFIG_EVA));
  	free_init_pages_eva = (config_enabled(CONFIG_EVA) ?
  			       free_init_pages_eva_malta : NULL);
  
  	while (p->size) {
  		long type;
  		unsigned long base, size;
  
  		type = fw_memtype_classify(p->type);
  		base = p->base;
  		size = p->size;
  
  		add_memory_region(base, size, type);
  		p++;
  	}
  }
  
  void __init prom_free_prom_memory(void)
  {
  	unsigned long addr;
  	int i;
  
  	for (i = 0; i < boot_mem_map.nr_map; i++) {
  		if (boot_mem_map.map[i].type != BOOT_MEM_ROM_DATA)
  			continue;
  
  		addr = boot_mem_map.map[i].addr;
  		free_init_pages("YAMON memory",
  				addr, addr + boot_mem_map.map[i].size);
  	}
  }
  
  unsigned platform_maar_init(unsigned num_pairs)
  {
  	phys_addr_t mem_end = (physical_memsize & ~0xffffull) - 1;
  	struct maar_config cfg[] = {
  		/* DRAM preceding I/O */
  		{ 0x00000000, 0x0fffffff, MIPS_MAAR_S },
  
  		/* DRAM following I/O */
  		{ 0x20000000, mem_end, MIPS_MAAR_S },
  
  		/* DRAM alias in upper half of physical */
  		{ 0x80000000, 0x80000000 + mem_end, MIPS_MAAR_S },
  	};
  	unsigned i, num_cfg = ARRAY_SIZE(cfg);
  
  	/* If DRAM fits before I/O, drop the region following it */
  	if (physical_memsize <= 0x10000000) {
  		num_cfg--;
  		for (i = 1; i < num_cfg; i++)
  			cfg[i] = cfg[i + 1];
  	}
  
  	return maar_config(cfg, num_cfg, num_pairs);
  }
  
  phys_addr_t mips_cdmm_phys_base(void)
  {
  	/* This address is "typically unused" */
  	return 0x1fc10000;
  }
  