linux/arch/powerpc/boot/devtree.c
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   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * devtree.c - convenience functions for device tree manipulation
   4 * Copyright 2007 David Gibson, IBM Corporation.
   5 * Copyright (c) 2007 Freescale Semiconductor, Inc.
   6 *
   7 * Authors: David Gibson <david@gibson.dropbear.id.au>
   8 *          Scott Wood <scottwood@freescale.com>
   9 */
  10#include <stdarg.h>
  11#include <stddef.h>
  12#include "types.h"
  13#include "string.h"
  14#include "stdio.h"
  15#include "ops.h"
  16
  17void dt_fixup_memory(u64 start, u64 size)
  18{
  19        void *root, *memory;
  20        int naddr, nsize, i;
  21        u32 memreg[4];
  22
  23        root = finddevice("/");
  24        if (getprop(root, "#address-cells", &naddr, sizeof(naddr)) < 0)
  25                naddr = 2;
  26        if (naddr < 1 || naddr > 2)
  27                fatal("Can't cope with #address-cells == %d in /\n\r", naddr);
  28
  29        if (getprop(root, "#size-cells", &nsize, sizeof(nsize)) < 0)
  30                nsize = 1;
  31        if (nsize < 1 || nsize > 2)
  32                fatal("Can't cope with #size-cells == %d in /\n\r", nsize);
  33
  34        i = 0;
  35        if (naddr == 2)
  36                memreg[i++] = start >> 32;
  37        memreg[i++] = start & 0xffffffff;
  38        if (nsize == 2)
  39                memreg[i++] = size >> 32;
  40        memreg[i++] = size & 0xffffffff;
  41
  42        memory = finddevice("/memory");
  43        if (! memory) {
  44                memory = create_node(NULL, "memory");
  45                setprop_str(memory, "device_type", "memory");
  46        }
  47
  48        printf("Memory <- <0x%x", memreg[0]);
  49        for (i = 1; i < (naddr + nsize); i++)
  50                printf(" 0x%x", memreg[i]);
  51        printf("> (%ldMB)\n\r", (unsigned long)(size >> 20));
  52
  53        setprop(memory, "reg", memreg, (naddr + nsize)*sizeof(u32));
  54}
  55
  56#define MHZ(x)  ((x + 500000) / 1000000)
  57
  58void dt_fixup_cpu_clocks(u32 cpu, u32 tb, u32 bus)
  59{
  60        void *devp = NULL;
  61
  62        printf("CPU clock-frequency <- 0x%x (%dMHz)\n\r", cpu, MHZ(cpu));
  63        printf("CPU timebase-frequency <- 0x%x (%dMHz)\n\r", tb, MHZ(tb));
  64        if (bus > 0)
  65                printf("CPU bus-frequency <- 0x%x (%dMHz)\n\r", bus, MHZ(bus));
  66
  67        while ((devp = find_node_by_devtype(devp, "cpu"))) {
  68                setprop_val(devp, "clock-frequency", cpu);
  69                setprop_val(devp, "timebase-frequency", tb);
  70                if (bus > 0)
  71                        setprop_val(devp, "bus-frequency", bus);
  72        }
  73
  74        timebase_period_ns = 1000000000 / tb;
  75}
  76
  77void dt_fixup_clock(const char *path, u32 freq)
  78{
  79        void *devp = finddevice(path);
  80
  81        if (devp) {
  82                printf("%s: clock-frequency <- %x (%dMHz)\n\r", path, freq, MHZ(freq));
  83                setprop_val(devp, "clock-frequency", freq);
  84        }
  85}
  86
  87void dt_fixup_mac_address_by_alias(const char *alias, const u8 *addr)
  88{
  89        void *devp = find_node_by_alias(alias);
  90
  91        if (devp) {
  92                printf("%s: local-mac-address <-"
  93                       " %02x:%02x:%02x:%02x:%02x:%02x\n\r", alias,
  94                       addr[0], addr[1], addr[2],
  95                       addr[3], addr[4], addr[5]);
  96
  97                setprop(devp, "local-mac-address", addr, 6);
  98        }
  99}
 100
 101void dt_fixup_mac_address(u32 index, const u8 *addr)
 102{
 103        void *devp = find_node_by_prop_value(NULL, "linux,network-index",
 104                                             (void*)&index, sizeof(index));
 105
 106        if (devp) {
 107                printf("ENET%d: local-mac-address <-"
 108                       " %02x:%02x:%02x:%02x:%02x:%02x\n\r", index,
 109                       addr[0], addr[1], addr[2],
 110                       addr[3], addr[4], addr[5]);
 111
 112                setprop(devp, "local-mac-address", addr, 6);
 113        }
 114}
 115
 116void __dt_fixup_mac_addresses(u32 startindex, ...)
 117{
 118        va_list ap;
 119        u32 index = startindex;
 120        const u8 *addr;
 121
 122        va_start(ap, startindex);
 123
 124        while ((addr = va_arg(ap, const u8 *)))
 125                dt_fixup_mac_address(index++, addr);
 126
 127        va_end(ap);
 128}
 129
 130#define MAX_ADDR_CELLS 4
 131
 132void dt_get_reg_format(void *node, u32 *naddr, u32 *nsize)
 133{
 134        if (getprop(node, "#address-cells", naddr, 4) != 4)
 135                *naddr = 2;
 136        if (getprop(node, "#size-cells", nsize, 4) != 4)
 137                *nsize = 1;
 138}
 139
 140static void copy_val(u32 *dest, u32 *src, int naddr)
 141{
 142        int pad = MAX_ADDR_CELLS - naddr;
 143
 144        memset(dest, 0, pad * 4);
 145        memcpy(dest + pad, src, naddr * 4);
 146}
 147
 148static int sub_reg(u32 *reg, u32 *sub)
 149{
 150        int i, borrow = 0;
 151
 152        for (i = MAX_ADDR_CELLS - 1; i >= 0; i--) {
 153                int prev_borrow = borrow;
 154                borrow = reg[i] < sub[i] + prev_borrow;
 155                reg[i] -= sub[i] + prev_borrow;
 156        }
 157
 158        return !borrow;
 159}
 160
 161static int add_reg(u32 *reg, u32 *add, int naddr)
 162{
 163        int i, carry = 0;
 164
 165        for (i = MAX_ADDR_CELLS - 1; i >= MAX_ADDR_CELLS - naddr; i--) {
 166                u64 tmp = (u64)reg[i] + add[i] + carry;
 167                carry = tmp >> 32;
 168                reg[i] = (u32)tmp;
 169        }
 170
 171        return !carry;
 172}
 173
 174/* It is assumed that if the first byte of reg fits in a
 175 * range, then the whole reg block fits.
 176 */
 177static int compare_reg(u32 *reg, u32 *range, u32 *rangesize)
 178{
 179        int i;
 180        u32 end;
 181
 182        for (i = 0; i < MAX_ADDR_CELLS; i++) {
 183                if (reg[i] < range[i])
 184                        return 0;
 185                if (reg[i] > range[i])
 186                        break;
 187        }
 188
 189        for (i = 0; i < MAX_ADDR_CELLS; i++) {
 190                end = range[i] + rangesize[i];
 191
 192                if (reg[i] < end)
 193                        break;
 194                if (reg[i] > end)
 195                        return 0;
 196        }
 197
 198        return reg[i] != end;
 199}
 200
 201/* reg must be MAX_ADDR_CELLS */
 202static int find_range(u32 *reg, u32 *ranges, int nregaddr,
 203                      int naddr, int nsize, int buflen)
 204{
 205        int nrange = nregaddr + naddr + nsize;
 206        int i;
 207
 208        for (i = 0; i + nrange <= buflen; i += nrange) {
 209                u32 range_addr[MAX_ADDR_CELLS];
 210                u32 range_size[MAX_ADDR_CELLS];
 211
 212                copy_val(range_addr, ranges + i, nregaddr);
 213                copy_val(range_size, ranges + i + nregaddr + naddr, nsize);
 214
 215                if (compare_reg(reg, range_addr, range_size))
 216                        return i;
 217        }
 218
 219        return -1;
 220}
 221
 222/* Currently only generic buses without special encodings are supported.
 223 * In particular, PCI is not supported.  Also, only the beginning of the
 224 * reg block is tracked; size is ignored except in ranges.
 225 */
 226static u32 prop_buf[MAX_PROP_LEN / 4];
 227
 228static int dt_xlate(void *node, int res, int reglen, unsigned long *addr,
 229                unsigned long *size)
 230{
 231        u32 last_addr[MAX_ADDR_CELLS];
 232        u32 this_addr[MAX_ADDR_CELLS];
 233        void *parent;
 234        u64 ret_addr, ret_size;
 235        u32 naddr, nsize, prev_naddr, prev_nsize;
 236        int buflen, offset;
 237
 238        parent = get_parent(node);
 239        if (!parent)
 240                return 0;
 241
 242        dt_get_reg_format(parent, &naddr, &nsize);
 243
 244        if (nsize > 2)
 245                return 0;
 246
 247        offset = (naddr + nsize) * res;
 248
 249        if (reglen < offset + naddr + nsize ||
 250            MAX_PROP_LEN < (offset + naddr + nsize) * 4)
 251                return 0;
 252
 253        copy_val(last_addr, prop_buf + offset, naddr);
 254
 255        ret_size = prop_buf[offset + naddr];
 256        if (nsize == 2) {
 257                ret_size <<= 32;
 258                ret_size |= prop_buf[offset + naddr + 1];
 259        }
 260
 261        for (;;) {
 262                prev_naddr = naddr;
 263                prev_nsize = nsize;
 264                node = parent;
 265
 266                parent = get_parent(node);
 267                if (!parent)
 268                        break;
 269
 270                dt_get_reg_format(parent, &naddr, &nsize);
 271
 272                buflen = getprop(node, "ranges", prop_buf,
 273                                sizeof(prop_buf));
 274                if (buflen == 0)
 275                        continue;
 276                if (buflen < 0 || buflen > sizeof(prop_buf))
 277                        return 0;
 278
 279                offset = find_range(last_addr, prop_buf, prev_naddr,
 280                                    naddr, prev_nsize, buflen / 4);
 281
 282                if (offset < 0)
 283                        return 0;
 284
 285                copy_val(this_addr, prop_buf + offset, prev_naddr);
 286
 287                if (!sub_reg(last_addr, this_addr))
 288                        return 0;
 289
 290                copy_val(this_addr, prop_buf + offset + prev_naddr, naddr);
 291
 292                if (!add_reg(last_addr, this_addr, naddr))
 293                        return 0;
 294        }
 295
 296        if (naddr > 2)
 297                return 0;
 298
 299        ret_addr = ((u64)last_addr[2] << 32) | last_addr[3];
 300
 301        if (sizeof(void *) == 4 &&
 302            (ret_addr >= 0x100000000ULL || ret_size > 0x100000000ULL ||
 303             ret_addr + ret_size > 0x100000000ULL))
 304                return 0;
 305
 306        *addr = ret_addr;
 307        if (size)
 308                *size = ret_size;
 309
 310        return 1;
 311}
 312
 313int dt_xlate_reg(void *node, int res, unsigned long *addr, unsigned long *size)
 314{
 315        int reglen;
 316
 317        reglen = getprop(node, "reg", prop_buf, sizeof(prop_buf)) / 4;
 318        return dt_xlate(node, res, reglen, addr, size);
 319}
 320
 321int dt_xlate_addr(void *node, u32 *buf, int buflen, unsigned long *xlated_addr)
 322{
 323
 324        if (buflen > sizeof(prop_buf))
 325                return 0;
 326
 327        memcpy(prop_buf, buf, buflen);
 328        return dt_xlate(node, 0, buflen / 4, xlated_addr, NULL);
 329}
 330
 331int dt_is_compatible(void *node, const char *compat)
 332{
 333        char *buf = (char *)prop_buf;
 334        int len, pos;
 335
 336        len = getprop(node, "compatible", buf, MAX_PROP_LEN);
 337        if (len < 0)
 338                return 0;
 339
 340        for (pos = 0; pos < len; pos++) {
 341                if (!strcmp(buf + pos, compat))
 342                        return 1;
 343
 344                pos += strnlen(&buf[pos], len - pos);
 345        }
 346
 347        return 0;
 348}
 349
 350int dt_get_virtual_reg(void *node, void **addr, int nres)
 351{
 352        unsigned long xaddr;
 353        int n;
 354
 355        n = getprop(node, "virtual-reg", addr, nres * 4);
 356        if (n > 0)
 357                return n / 4;
 358
 359        for (n = 0; n < nres; n++) {
 360                if (!dt_xlate_reg(node, n, &xaddr, NULL))
 361                        break;
 362
 363                addr[n] = (void *)xaddr;
 364        }
 365
 366        return n;
 367}
 368
 369