// SPDX-License-Identifier: GPL-2.0+
/*
 * Copyright (C) 2016 Stefan Roese <sr@denx.de>
 * Copyright (C) 2020 Marek Behun <marek.behun@nic.cz>
 */

#include <common.h>
#include <cpu_func.h>
#include <dm.h>
#include <fdtdec.h>
#include <fdt_support.h>
#include <init.h>
#include <asm/global_data.h>
#include <linux/bitops.h>
#include <linux/libfdt.h>
#include <asm/io.h>
#include <asm/system.h>
#include <asm/arch/cpu.h>
#include <asm/arch/soc.h>
#include <asm/armv8/mmu.h>
#include <sort.h>

/* Armada 3700 */
#define MVEBU_GPIO_NB_REG_BASE          (MVEBU_REGISTER(0x13800))

#define MVEBU_TEST_PIN_LATCH_N          (MVEBU_GPIO_NB_REG_BASE + 0x8)
#define MVEBU_XTAL_MODE_MASK            BIT(9)
#define MVEBU_XTAL_MODE_OFFS            9
#define MVEBU_XTAL_CLOCK_25MHZ          0x0
#define MVEBU_XTAL_CLOCK_40MHZ          0x1

#define MVEBU_NB_WARM_RST_REG           (MVEBU_GPIO_NB_REG_BASE + 0x40)
#define MVEBU_NB_WARM_RST_MAGIC_NUM     0x1d1e

/* Armada 3700 CPU Address Decoder registers */
#define MVEBU_CPU_DEC_WIN_REG_BASE      (size_t)(MVEBU_REGISTER(0xcf00))
#define MVEBU_CPU_DEC_WIN_CTRL(w) \
        (MVEBU_CPU_DEC_WIN_REG_BASE + ((w) << 4))
#define MVEBU_CPU_DEC_WIN_CTRL_EN       BIT(0)
#define MVEBU_CPU_DEC_WIN_CTRL_TGT_MASK 0xf
#define MVEBU_CPU_DEC_WIN_CTRL_TGT_OFFS 4
#define MVEBU_CPU_DEC_WIN_CTRL_TGT_DRAM 0
#define MVEBU_CPU_DEC_WIN_CTRL_TGT_PCIE 2
#define MVEBU_CPU_DEC_WIN_SIZE(w)       (MVEBU_CPU_DEC_WIN_CTRL(w) + 0x4)
#define MVEBU_CPU_DEC_WIN_BASE(w)       (MVEBU_CPU_DEC_WIN_CTRL(w) + 0x8)
#define MVEBU_CPU_DEC_WIN_REMAP(w)      (MVEBU_CPU_DEC_WIN_CTRL(w) + 0xc)
#define MVEBU_CPU_DEC_WIN_GRANULARITY   16
#define MVEBU_CPU_DEC_WINS              5

#define MAX_MEM_MAP_REGIONS             (MVEBU_CPU_DEC_WINS + 2)

#define A3700_PTE_BLOCK_NORMAL \
        (PTE_BLOCK_MEMTYPE(MT_NORMAL) | PTE_BLOCK_INNER_SHARE)
#define A3700_PTE_BLOCK_DEVICE \
        (PTE_BLOCK_MEMTYPE(MT_DEVICE_NGNRNE) | PTE_BLOCK_NON_SHARE)

DECLARE_GLOBAL_DATA_PTR;

static struct mm_region mvebu_mem_map[MAX_MEM_MAP_REGIONS] = {
        {
                /*
                 * SRAM, MMIO regions
                 * Don't remove this, a3700_build_mem_map needs it.
                 */
                .phys = SOC_REGS_PHY_BASE,
                .virt = SOC_REGS_PHY_BASE,
                .size = 0x02000000UL,   /* 32MiB internal registers */
                .attrs = A3700_PTE_BLOCK_DEVICE
        },
};

struct mm_region *mem_map = mvebu_mem_map;

static int get_cpu_dec_win(int win, u32 *tgt, u32 *base, u32 *size)
{
        u32 reg;

        reg = readl(MVEBU_CPU_DEC_WIN_CTRL(win));
        if (!(reg & MVEBU_CPU_DEC_WIN_CTRL_EN))
                return -1;

        if (tgt) {
                reg >>= MVEBU_CPU_DEC_WIN_CTRL_TGT_OFFS;
                reg &= MVEBU_CPU_DEC_WIN_CTRL_TGT_MASK;
                *tgt = reg;
        }

        if (base) {
                reg = readl(MVEBU_CPU_DEC_WIN_BASE(win));
                *base = reg << MVEBU_CPU_DEC_WIN_GRANULARITY;
        }

        if (size) {
                /*
                 * Window size is encoded as the number of 1s from LSB to MSB,
                 * followed by 0s. The number of 1s specifies the size in 64 KiB
                 * granularity.
                 */
                reg = readl(MVEBU_CPU_DEC_WIN_SIZE(win));
                *size = ((reg + 1) << MVEBU_CPU_DEC_WIN_GRANULARITY);
        }

        return 0;
}

/*
 * Builds mem_map according to CPU Address Decoder settings, which were set by
 * the TIMH image on the Cortex-M3 secure processor, or by ARM Trusted Firmware
 */
static void build_mem_map(void)
{
        int win, region;

        region = 1;
        for (win = 0; win < MVEBU_CPU_DEC_WINS; ++win) {
                u32 base, tgt, size;
                u64 attrs;

                /* skip disabled windows */
                if (get_cpu_dec_win(win, &tgt, &base, &size))
                        continue;

                if (tgt == MVEBU_CPU_DEC_WIN_CTRL_TGT_DRAM)
                        attrs = A3700_PTE_BLOCK_NORMAL;
                else if (tgt == MVEBU_CPU_DEC_WIN_CTRL_TGT_PCIE)
                        attrs = A3700_PTE_BLOCK_DEVICE;
                else
                        /* skip windows with other targets */
                        continue;

                mvebu_mem_map[region].phys = base;
                mvebu_mem_map[region].virt = base;
                mvebu_mem_map[region].size = size;
                mvebu_mem_map[region].attrs = attrs;
                ++region;
        }

        /* add list terminator */
        mvebu_mem_map[region].size = 0;
        mvebu_mem_map[region].attrs = 0;
}

void enable_caches(void)
{
        build_mem_map();

        icache_enable();
        dcache_enable();
}

int a3700_dram_init(void)
{
        int win;

        gd->ram_size = 0;
        for (win = 0; win < MVEBU_CPU_DEC_WINS; ++win) {
                u32 base, tgt, size;

                /* skip disabled windows */
                if (get_cpu_dec_win(win, &tgt, &base, &size))
                        continue;

                /* skip non-DRAM windows */
                if (tgt != MVEBU_CPU_DEC_WIN_CTRL_TGT_DRAM)
                        continue;

                /*
                 * It is possible that one image was built for boards with
                 * different RAM sizes, for example 512 MiB and 1 GiB.
                 * We therefore try to determine the actual RAM size in the
                 * window with get_ram_size.
                 */
                gd->ram_size += get_ram_size((void *)(size_t)base, size);
        }

        return 0;
}

struct a3700_dram_window {
        size_t base, size;
};

static int dram_win_cmp(const void *a, const void *b)
{
        size_t ab, bb;

        ab = ((const struct a3700_dram_window *)a)->base;
        bb = ((const struct a3700_dram_window *)b)->base;

        if (ab < bb)
                return -1;
        else if (ab > bb)
                return 1;
        else
                return 0;
}

int a3700_dram_init_banksize(void)
{
        struct a3700_dram_window dram_wins[MVEBU_CPU_DEC_WINS];
        int bank, win, ndram_wins;
        u32 last_end;
        size_t size;

        ndram_wins = 0;
        for (win = 0; win < MVEBU_CPU_DEC_WINS; ++win) {
                u32 base, tgt, size;

                /* skip disabled windows */
                if (get_cpu_dec_win(win, &tgt, &base, &size))
                        continue;

                /* skip non-DRAM windows */
                if (tgt != MVEBU_CPU_DEC_WIN_CTRL_TGT_DRAM)
                        continue;

                dram_wins[win].base = base;
                dram_wins[win].size = size;
                ++ndram_wins;
        }

        qsort(dram_wins, ndram_wins, sizeof(dram_wins[0]), dram_win_cmp);

        bank = 0;
        last_end = -1;

        for (win = 0; win < ndram_wins; ++win) {
                /* again determining actual RAM size as in a3700_dram_init */
                size = get_ram_size((void *)dram_wins[win].base,
                                    dram_wins[win].size);

                /*
                 * Check if previous window ends as the current starts. If yes,
                 * merge these windows into one "bank". This is possible by this
                 * simple check thanks to mem_map regions being qsorted in
                 * build_mem_map.
                 */
                if (last_end == dram_wins[win].base) {
                        gd->bd->bi_dram[bank - 1].size += size;
                        last_end += size;
                } else {
                        if (bank == CONFIG_NR_DRAM_BANKS) {
                                printf("Need more CONFIG_NR_DRAM_BANKS\n");
                                return -ENOBUFS;
                        }

                        gd->bd->bi_dram[bank].start = dram_wins[win].base;
                        gd->bd->bi_dram[bank].size = size;
                        last_end = dram_wins[win].base + size;
                        ++bank;
                }
        }

        /*
         * If there is more place for DRAM BANKS definitions than needed, fill
         * the rest with zeros.
         */
        for (; bank < CONFIG_NR_DRAM_BANKS; ++bank) {
                gd->bd->bi_dram[bank].start = 0;
                gd->bd->bi_dram[bank].size = 0;
        }

        return 0;
}

static u32 find_pcie_window_base(void)
{
        int win;

        for (win = 0; win < MVEBU_CPU_DEC_WINS; ++win) {
                u32 base, tgt;

                /* skip disabled windows */
                if (get_cpu_dec_win(win, &tgt, &base, NULL))
                        continue;

                if (tgt == MVEBU_CPU_DEC_WIN_CTRL_TGT_PCIE)
                        return base;
        }

        return -1;
}

static int fdt_setprop_inplace_u32_partial(void *blob, int node,
                                           const char *name,
                                           u32 idx, u32 val)
{
        val = cpu_to_fdt32(val);

        return fdt_setprop_inplace_namelen_partial(blob, node, name,
                                                   strlen(name),
                                                   idx * sizeof(u32),
                                                   &val, sizeof(u32));
}

int a3700_fdt_fix_pcie_regions(void *blob)
{
        int acells, pacells, scells;
        u32 base, fix_offset;
        const u32 *ranges;
        int node, pnode;
        int ret, i, len;

        base = find_pcie_window_base();
        if (base == -1)
                return -ENOENT;

        node = fdt_node_offset_by_compatible(blob, -1, "marvell,armada-3700-pcie");
        if (node < 0)
                return node;

        ranges = fdt_getprop(blob, node, "ranges", &len);
        if (!ranges || len % sizeof(u32))
                return -ENOENT;

        /*
         * The "ranges" property is an array of
         * { <child address> <parent address> <size in child address space> }
         *
         * All 3 elements can span a diffent number of cells. Fetch their sizes.
         */
        pnode = fdt_parent_offset(blob, node);
        acells = fdt_address_cells(blob, node);
        pacells = fdt_address_cells(blob, pnode);
        scells = fdt_size_cells(blob, node);

        /* Child PCI addresses always use 3 cells */
        if (acells != 3)
                return -ENOENT;

        /* Calculate fixup offset from first child address (in last cell) */
        fix_offset = base - fdt32_to_cpu(ranges[2]);

        /* If fixup offset is zero then there is nothing to fix */
        if (!fix_offset)
                return 0;

        /*
         * Fix address (last cell) of each child address and each parent
         * address
         */
        for (i = 0; i < len / sizeof(u32); i += acells + pacells + scells) {
                int idx;

                /* fix child address */
                idx = i + acells - 1;
                ret = fdt_setprop_inplace_u32_partial(blob, node, "ranges", idx,
                                                      fdt32_to_cpu(ranges[idx]) +
                                                      fix_offset);
                if (ret)
                        return ret;

                /* fix parent address */
                idx = i + acells + pacells - 1;
                ret = fdt_setprop_inplace_u32_partial(blob, node, "ranges", idx,
                                                      fdt32_to_cpu(ranges[idx]) +
                                                      fix_offset);
                if (ret)
                        return ret;
        }

        return 0;
}

void reset_cpu(void)
{
        /*
         * Write magic number of 0x1d1e to North Bridge Warm Reset register
         * to trigger warm reset
         */
        writel(MVEBU_NB_WARM_RST_MAGIC_NUM, MVEBU_NB_WARM_RST_REG);
}

/*
 * get_ref_clk
 *
 * return: reference clock in MHz (25 or 40)
 */
u32 get_ref_clk(void)
{
        u32 regval;

        regval = (readl(MVEBU_TEST_PIN_LATCH_N) & MVEBU_XTAL_MODE_MASK) >>
                MVEBU_XTAL_MODE_OFFS;

        if (regval == MVEBU_XTAL_CLOCK_25MHZ)
                return 25;
        else
                return 40;
}