// SPDX-License-Identifier: GPL-2.0-only
/*
 *  PS3 pagetable management routines.
 *
 *  Copyright (C) 2006 Sony Computer Entertainment Inc.
 *  Copyright 2006, 2007 Sony Corporation
 */

#include <linux/kernel.h>
#include <linux/memblock.h>

#include <asm/machdep.h>
#include <asm/prom.h>
#include <asm/udbg.h>
#include <asm/lv1call.h>
#include <asm/ps3fb.h>

#define PS3_VERBOSE_RESULT
#include "platform.h"

/**
 * enum lpar_vas_id - id of LPAR virtual address space.
 * @lpar_vas_id_current: Current selected virtual address space
 *
 * Identify the target LPAR address space.
 */

enum ps3_lpar_vas_id {
        PS3_LPAR_VAS_ID_CURRENT = 0,
};


static DEFINE_SPINLOCK(ps3_htab_lock);

static long ps3_hpte_insert(unsigned long hpte_group, unsigned long vpn,
        unsigned long pa, unsigned long rflags, unsigned long vflags,
        int psize, int apsize, int ssize)
{
        int result;
        u64 hpte_v, hpte_r;
        u64 inserted_index;
        u64 evicted_v, evicted_r;
        u64 hpte_v_array[4], hpte_rs;
        unsigned long flags;
        long ret = -1;

        /*
         * lv1_insert_htab_entry() will search for victim
         * entry in both primary and secondary pte group
         */
        vflags &= ~HPTE_V_SECONDARY;

        hpte_v = hpte_encode_v(vpn, psize, apsize, ssize) | vflags | HPTE_V_VALID;
        hpte_r = hpte_encode_r(ps3_mm_phys_to_lpar(pa), psize, apsize) | rflags;

        spin_lock_irqsave(&ps3_htab_lock, flags);

        /* talk hvc to replace entries BOLTED == 0 */
        result = lv1_insert_htab_entry(PS3_LPAR_VAS_ID_CURRENT, hpte_group,
                                       hpte_v, hpte_r,
                                       HPTE_V_BOLTED, 0,
                                       &inserted_index,
                                       &evicted_v, &evicted_r);

        if (result) {
                /* all entries bolted !*/
                pr_info("%s:result=%s vpn=%lx pa=%lx ix=%lx v=%llx r=%llx\n",
                        __func__, ps3_result(result), vpn, pa, hpte_group,
                        hpte_v, hpte_r);
                BUG();
        }

        /*
         * see if the entry is inserted into secondary pteg
         */
        result = lv1_read_htab_entries(PS3_LPAR_VAS_ID_CURRENT,
                                       inserted_index & ~0x3UL,
                                       &hpte_v_array[0], &hpte_v_array[1],
                                       &hpte_v_array[2], &hpte_v_array[3],
                                       &hpte_rs);
        BUG_ON(result);

        if (hpte_v_array[inserted_index % 4] & HPTE_V_SECONDARY)
                ret = (inserted_index & 7) | (1 << 3);
        else
                ret = inserted_index & 7;

        spin_unlock_irqrestore(&ps3_htab_lock, flags);

        return ret;
}

static long ps3_hpte_remove(unsigned long hpte_group)
{
        panic("ps3_hpte_remove() not implemented");
        return 0;
}

static long ps3_hpte_updatepp(unsigned long slot, unsigned long newpp,
                              unsigned long vpn, int psize, int apsize,
                              int ssize, unsigned long inv_flags)
{
        int result;
        u64 hpte_v, want_v, hpte_rs;
        u64 hpte_v_array[4];
        unsigned long flags;
        long ret;

        want_v = hpte_encode_avpn(vpn, psize, ssize);

        spin_lock_irqsave(&ps3_htab_lock, flags);

        result = lv1_read_htab_entries(PS3_LPAR_VAS_ID_CURRENT, slot & ~0x3UL,
                                       &hpte_v_array[0], &hpte_v_array[1],
                                       &hpte_v_array[2], &hpte_v_array[3],
                                       &hpte_rs);

        if (result) {
                pr_info("%s: result=%s read vpn=%lx slot=%lx psize=%d\n",
                        __func__, ps3_result(result), vpn, slot, psize);
                BUG();
        }

        hpte_v = hpte_v_array[slot % 4];

        /*
         * As lv1_read_htab_entries() does not give us the RPN, we can
         * not synthesize the new hpte_r value here, and therefore can
         * not update the hpte with lv1_insert_htab_entry(), so we
         * instead invalidate it and ask the caller to update it via
         * ps3_hpte_insert() by returning a -1 value.
         */
        if (!HPTE_V_COMPARE(hpte_v, want_v) || !(hpte_v & HPTE_V_VALID)) {
                /* not found */
                ret = -1;
        } else {
                /* entry found, just invalidate it */
                result = lv1_write_htab_entry(PS3_LPAR_VAS_ID_CURRENT,
                                              slot, 0, 0);
                ret = -1;
        }

        spin_unlock_irqrestore(&ps3_htab_lock, flags);
        return ret;
}

static void ps3_hpte_updateboltedpp(unsigned long newpp, unsigned long ea,
        int psize, int ssize)
{
        panic("ps3_hpte_updateboltedpp() not implemented");
}

static void ps3_hpte_invalidate(unsigned long slot, unsigned long vpn,
                                int psize, int apsize, int ssize, int local)
{
        unsigned long flags;
        int result;

        spin_lock_irqsave(&ps3_htab_lock, flags);

        result = lv1_write_htab_entry(PS3_LPAR_VAS_ID_CURRENT, slot, 0, 0);

        if (result) {
                pr_info("%s: result=%s vpn=%lx slot=%lx psize=%d\n",
                        __func__, ps3_result(result), vpn, slot, psize);
                BUG();
        }

        spin_unlock_irqrestore(&ps3_htab_lock, flags);
}

static void ps3_hpte_clear(void)
{
        unsigned long hpte_count = (1UL << ppc64_pft_size) >> 4;
        u64 i;

        for (i = 0; i < hpte_count; i++)
                lv1_write_htab_entry(PS3_LPAR_VAS_ID_CURRENT, i, 0, 0);

        ps3_mm_shutdown();
        ps3_mm_vas_destroy();
}

void __init ps3_hpte_init(unsigned long htab_size)
{
        mmu_hash_ops.hpte_invalidate = ps3_hpte_invalidate;
        mmu_hash_ops.hpte_updatepp = ps3_hpte_updatepp;
        mmu_hash_ops.hpte_updateboltedpp = ps3_hpte_updateboltedpp;
        mmu_hash_ops.hpte_insert = ps3_hpte_insert;
        mmu_hash_ops.hpte_remove = ps3_hpte_remove;
        mmu_hash_ops.hpte_clear_all = ps3_hpte_clear;

        ppc64_pft_size = __ilog2(htab_size);
}