// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * 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>
 */
#include <stdarg.h>
#include <stddef.h>
#include "types.h"
#include "string.h"
#include "stdio.h"
#include "ops.h"
#include "of.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;
        else
                naddr = be32_to_cpu(naddr);
        if (naddr < 1 || naddr > 2)
                fatal("Can't cope with #address-cells == %d in /\n\r", naddr);

        if (getprop(root, "#size-cells", &nsize, sizeof(nsize)) < 0)
                nsize = 1;
        else
                nsize = be32_to_cpu(nsize);
        if (nsize < 1 || nsize > 2)
                fatal("Can't cope with #size-cells == %d in /\n\r", nsize);

        i = 0;
        if (naddr == 2)
                memreg[i++] = cpu_to_be32(start >> 32);
        memreg[i++] = cpu_to_be32(start & 0xffffffff);
        if (nsize == 2)
                memreg[i++] = cpu_to_be32(size >> 32);
        memreg[i++] = cpu_to_be32(size & 0xffffffff);

        memory = finddevice("/memory");
        if (! memory) {
                memory = create_node(NULL, "memory");
                setprop_str(memory, "device_type", "memory");
        }

        printf("Memory <- <0x%x", be32_to_cpu(memreg[0]));
        for (i = 1; i < (naddr + nsize); i++)
                printf(" 0x%x", be32_to_cpu(memreg[i]));
        printf("> (%ldMB)\n\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)\n\r", cpu, MHZ(cpu));
        printf("CPU timebase-frequency <- 0x%x (%dMHz)\n\r", tb, MHZ(tb));
        if (bus > 0)
                printf("CPU bus-frequency <- 0x%x (%dMHz)\n\r", bus, MHZ(bus));

        while ((devp = find_node_by_devtype(devp, "cpu"))) {
                setprop_val(devp, "clock-frequency", cpu_to_be32(cpu));
                setprop_val(devp, "timebase-frequency", cpu_to_be32(tb));
                if (bus > 0)
                        setprop_val(devp, "bus-frequency", cpu_to_be32(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)\n\r", path, freq, MHZ(freq));
                setprop_val(devp, "clock-frequency", cpu_to_be32(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\n\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\n\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;
        else
                *naddr = be32_to_cpu(*naddr);
        if (getprop(node, "#size-cells", nsize, 4) != 4)
                *nsize = 1;
        else
                *nsize = be32_to_cpu(*nsize);
}

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)be32_to_cpu(reg[i]) + be32_to_cpu(add[i]) + carry;
                carry = tmp >> 32;
                reg[i] = cpu_to_be32((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 (be32_to_cpu(reg[i]) < be32_to_cpu(range[i]))
                        return 0;
                if (be32_to_cpu(reg[i]) > be32_to_cpu(range[i]))
                        break;
        }

        for (i = 0; i < MAX_ADDR_CELLS; i++) {
                end = be32_to_cpu(range[i]) + be32_to_cpu(rangesize[i]);

                if (be32_to_cpu(reg[i]) < end)
                        break;
                if (be32_to_cpu(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 = be32_to_cpu(prop_buf[offset + naddr]);
        if (nsize == 2) {
                ret_size <<= 32;
                ret_size |= be32_to_cpu(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)be32_to_cpu(last_addr[2]) << 32) | be32_to_cpu(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, i;

        n = getprop(node, "virtual-reg", addr, nres * 4);
        if (n > 0) {
                for (i = 0; i < n/4; i ++)
                        ((u32 *)addr)[i] = be32_to_cpu(((u32 *)addr)[i]);
                return n / 4;
        }

        for (n = 0; n < nres; n++) {
                if (!dt_xlate_reg(node, n, &xaddr, NULL))
                        break;

                addr[n] = (void *)xaddr;
        }

        return n;
}