/*
   * devtree.c - convenience functions for device tree manipulation
   * Copyright 2007 David Gibson, IBM Corporation.
   * Copyright (c) 2007 Freescale Semiconductor, Inc.
   *
   * Authors: David Gibson <david@gibson.dropbear.id.au>
   *	    Scott Wood <scottwood@freescale.com>
   *
   * This program is free software; you can redistribute it and/or
   * modify it under the terms of the GNU General Public License
   * as published by the Free Software Foundation; either version
   * 2 of the License, or (at your option) any later version.
   */
  #include <stdarg.h>
  #include <stddef.h>
  #include "types.h"
  #include "string.h"
  #include "stdio.h"
  #include "ops.h"
  
  void dt_fixup_memory(u64 start, u64 size)
  {
  	void *root, *memory;
  	int naddr, nsize, i;
  	u32 memreg[4];
  
  	root = finddevice("/");
  	if (getprop(root, "#address-cells", &naddr, sizeof(naddr)) < 0)
  		naddr = 2;
  	if (naddr < 1 || naddr > 2)
  		fatal("Can't cope with #address-cells == %d in /
  \r", naddr);
  
  	if (getprop(root, "#size-cells", &nsize, sizeof(nsize)) < 0)
  		nsize = 1;
  	if (nsize < 1 || nsize > 2)
  		fatal("Can't cope with #size-cells == %d in /
  \r", nsize);
  
  	i = 0;
  	if (naddr == 2)
  		memreg[i++] = start >> 32;
  	memreg[i++] = start & 0xffffffff;
  	if (nsize == 2)
  		memreg[i++] = size >> 32;
  	memreg[i++] = size & 0xffffffff;
  
  	memory = finddevice("/memory");
  	if (! memory) {
  		memory = create_node(NULL, "memory");
  		setprop_str(memory, "device_type", "memory");
  	}
  
  	printf("Memory <- <0x%x", memreg[0]);
  	for (i = 1; i < (naddr + nsize); i++)
  		printf(" 0x%x", memreg[i]);
  	printf("> (%ldMB)
  \r", (unsigned long)(size >> 20));
  
  	setprop(memory, "reg", memreg, (naddr + nsize)*sizeof(u32));
  }
  
  #define MHZ(x)	((x + 500000) / 1000000)
  
  void dt_fixup_cpu_clocks(u32 cpu, u32 tb, u32 bus)
  {
  	void *devp = NULL;
  
  	printf("CPU clock-frequency <- 0x%x (%dMHz)
  \r", cpu, MHZ(cpu));
  	printf("CPU timebase-frequency <- 0x%x (%dMHz)
  \r", tb, MHZ(tb));
  	if (bus > 0)
  		printf("CPU bus-frequency <- 0x%x (%dMHz)
  \r", bus, MHZ(bus));
  
  	while ((devp = find_node_by_devtype(devp, "cpu"))) {
  		setprop_val(devp, "clock-frequency", cpu);
  		setprop_val(devp, "timebase-frequency", tb);
  		if (bus > 0)
  			setprop_val(devp, "bus-frequency", bus);
  	}

  
  	timebase_period_ns = 1000000000 / tb;

  }
  
  void dt_fixup_clock(const char *path, u32 freq)
  {
  	void *devp = finddevice(path);
  
  	if (devp) {
  		printf("%s: clock-frequency <- %x (%dMHz)
  \r", path, freq, MHZ(freq));
  		setprop_val(devp, "clock-frequency", freq);
  	}
  }

  void dt_fixup_mac_address_by_alias(const char *alias, const u8 *addr)
  {
  	void *devp = find_node_by_alias(alias);
  
  	if (devp) {
  		printf("%s: local-mac-address <-"
  		       " %02x:%02x:%02x:%02x:%02x:%02x
  \r", alias,
  		       addr[0], addr[1], addr[2],
  		       addr[3], addr[4], addr[5]);
  
  		setprop(devp, "local-mac-address", addr, 6);
  	}
  }

  void dt_fixup_mac_address(u32 index, const u8 *addr)
  {
  	void *devp = find_node_by_prop_value(NULL, "linux,network-index",
  	                                     (void*)&index, sizeof(index));
  
  	if (devp) {
  		printf("ENET%d: local-mac-address <-"
  		       " %02x:%02x:%02x:%02x:%02x:%02x
  \r", index,
  		       addr[0], addr[1], addr[2],
  		       addr[3], addr[4], addr[5]);
  
  		setprop(devp, "local-mac-address", addr, 6);
  	}
  }

  void __dt_fixup_mac_addresses(u32 startindex, ...)
  {
  	va_list ap;
  	u32 index = startindex;

  	const u8 *addr;
  
  	va_start(ap, startindex);

  	while ((addr = va_arg(ap, const u8 *)))
  		dt_fixup_mac_address(index++, addr);

  	va_end(ap);
  }

  
  #define MAX_ADDR_CELLS 4

  void dt_get_reg_format(void *node, u32 *naddr, u32 *nsize)

  {
  	if (getprop(node, "#address-cells", naddr, 4) != 4)
  		*naddr = 2;
  	if (getprop(node, "#size-cells", nsize, 4) != 4)
  		*nsize = 1;
  }
  
  static void copy_val(u32 *dest, u32 *src, int naddr)
  {

  	int pad = MAX_ADDR_CELLS - naddr;
  
  	memset(dest, 0, pad * 4);
  	memcpy(dest + pad, src, naddr * 4);

  }
  
  static int sub_reg(u32 *reg, u32 *sub)
  {
  	int i, borrow = 0;

  	for (i = MAX_ADDR_CELLS - 1; i >= 0; i--) {

  		int prev_borrow = borrow;
  		borrow = reg[i] < sub[i] + prev_borrow;
  		reg[i] -= sub[i] + prev_borrow;
  	}
  
  	return !borrow;
  }

  static int add_reg(u32 *reg, u32 *add, int naddr)

  {
  	int i, carry = 0;

  	for (i = MAX_ADDR_CELLS - 1; i >= MAX_ADDR_CELLS - naddr; i--) {

  		u64 tmp = (u64)reg[i] + add[i] + carry;
  		carry = tmp >> 32;
  		reg[i] = (u32)tmp;
  	}
  
  	return !carry;
  }
  
  /* It is assumed that if the first byte of reg fits in a
   * range, then the whole reg block fits.
   */
  static int compare_reg(u32 *reg, u32 *range, u32 *rangesize)
  {
  	int i;
  	u32 end;
  
  	for (i = 0; i < MAX_ADDR_CELLS; i++) {
  		if (reg[i] < range[i])
  			return 0;
  		if (reg[i] > range[i])
  			break;
  	}
  
  	for (i = 0; i < MAX_ADDR_CELLS; i++) {
  		end = range[i] + rangesize[i];
  
  		if (reg[i] < end)
  			break;
  		if (reg[i] > end)
  			return 0;
  	}
  
  	return reg[i] != end;
  }
  
  /* reg must be MAX_ADDR_CELLS */
  static int find_range(u32 *reg, u32 *ranges, int nregaddr,
                        int naddr, int nsize, int buflen)
  {
  	int nrange = nregaddr + naddr + nsize;
  	int i;
  
  	for (i = 0; i + nrange <= buflen; i += nrange) {
  		u32 range_addr[MAX_ADDR_CELLS];
  		u32 range_size[MAX_ADDR_CELLS];

  		copy_val(range_addr, ranges + i, nregaddr);

  		copy_val(range_size, ranges + i + nregaddr + naddr, nsize);
  
  		if (compare_reg(reg, range_addr, range_size))
  			return i;
  	}
  
  	return -1;
  }
  
  /* Currently only generic buses without special encodings are supported.
   * In particular, PCI is not supported.  Also, only the beginning of the
   * reg block is tracked; size is ignored except in ranges.
   */

  static u32 prop_buf[MAX_PROP_LEN / 4];

  
  static int dt_xlate(void *node, int res, int reglen, unsigned long *addr,
  		unsigned long *size)

  {
  	u32 last_addr[MAX_ADDR_CELLS];
  	u32 this_addr[MAX_ADDR_CELLS];

  	void *parent;
  	u64 ret_addr, ret_size;

  	u32 naddr, nsize, prev_naddr, prev_nsize;

  	int buflen, offset;
  
  	parent = get_parent(node);
  	if (!parent)
  		return 0;

  	dt_get_reg_format(parent, &naddr, &nsize);

  
  	if (nsize > 2)
  		return 0;

  	offset = (naddr + nsize) * res;

  	if (reglen < offset + naddr + nsize ||

  	    MAX_PROP_LEN < (offset + naddr + nsize) * 4)

  		return 0;

  	copy_val(last_addr, prop_buf + offset, naddr);

  	ret_size = prop_buf[offset + naddr];

  	if (nsize == 2) {
  		ret_size <<= 32;

  		ret_size |= prop_buf[offset + naddr + 1];

  	}

  	for (;;) {

  		prev_naddr = naddr;

  		prev_nsize = nsize;
  		node = parent;

  		parent = get_parent(node);
  		if (!parent)
  			break;

  		dt_get_reg_format(parent, &naddr, &nsize);

  		buflen = getprop(node, "ranges", prop_buf,
  				sizeof(prop_buf));

  		if (buflen == 0)

  			continue;

  		if (buflen < 0 || buflen > sizeof(prop_buf))

  			return 0;

  		offset = find_range(last_addr, prop_buf, prev_naddr,

  		                    naddr, prev_nsize, buflen / 4);

  
  		if (offset < 0)
  			return 0;

  		copy_val(this_addr, prop_buf + offset, prev_naddr);

  
  		if (!sub_reg(last_addr, this_addr))
  			return 0;

  		copy_val(this_addr, prop_buf + offset + prev_naddr, naddr);

  		if (!add_reg(last_addr, this_addr, naddr))

  			return 0;
  	}
  
  	if (naddr > 2)
  		return 0;

  	ret_addr = ((u64)last_addr[2] << 32) | last_addr[3];

  
  	if (sizeof(void *) == 4 &&
  	    (ret_addr >= 0x100000000ULL || ret_size > 0x100000000ULL ||
  	     ret_addr + ret_size > 0x100000000ULL))
  		return 0;
  
  	*addr = ret_addr;
  	if (size)
  		*size = ret_size;
  
  	return 1;
  }

  
  int dt_xlate_reg(void *node, int res, unsigned long *addr, unsigned long *size)
  {
  	int reglen;

  	reglen = getprop(node, "reg", prop_buf, sizeof(prop_buf)) / 4;

  	return dt_xlate(node, res, reglen, addr, size);
  }
  
  int dt_xlate_addr(void *node, u32 *buf, int buflen, unsigned long *xlated_addr)
  {

  	if (buflen > sizeof(prop_buf))

  		return 0;

  	memcpy(prop_buf, buf, buflen);

  	return dt_xlate(node, 0, buflen / 4, xlated_addr, NULL);
  }

  
  int dt_is_compatible(void *node, const char *compat)
  {
  	char *buf = (char *)prop_buf;
  	int len, pos;
  
  	len = getprop(node, "compatible", buf, MAX_PROP_LEN);
  	if (len < 0)
  		return 0;
  
  	for (pos = 0; pos < len; pos++) {
  		if (!strcmp(buf + pos, compat))
  			return 1;
  
  		pos += strnlen(&buf[pos], len - pos);
  	}
  
  	return 0;
  }

  
  int dt_get_virtual_reg(void *node, void **addr, int nres)
  {
  	unsigned long xaddr;
  	int n;
  
  	n = getprop(node, "virtual-reg", addr, nres * 4);
  	if (n > 0)
  		return n / 4;
  
  	for (n = 0; n < nres; n++) {
  		if (!dt_xlate_reg(node, n, &xaddr, NULL))
  			break;
  
  		addr[n] = (void *)xaddr;
  	}
  
  	return n;
  }