/*
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License, version 2, as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 *
 * Copyright IBM Corp. 2008
 *
 * Authors: Hollis Blanchard <hollisb@us.ibm.com>
 */

#include <linux/kvm_host.h>
#include <linux/slab.h>
#include <linux/err.h>
#include <linux/export.h>
#include <linux/module.h>
#include <linux/miscdevice.h>

#include <asm/reg.h>
#include <asm/cputable.h>
#include <asm/tlbflush.h>
#include <asm/kvm_44x.h>
#include <asm/kvm_ppc.h>

#include "44x_tlb.h"
#include "booke.h"

static void kvmppc_core_vcpu_load_44x(struct kvm_vcpu *vcpu, int cpu)
{
        kvmppc_booke_vcpu_load(vcpu, cpu);
        kvmppc_44x_tlb_load(vcpu);
}

static void kvmppc_core_vcpu_put_44x(struct kvm_vcpu *vcpu)
{
        kvmppc_44x_tlb_put(vcpu);
        kvmppc_booke_vcpu_put(vcpu);
}

int kvmppc_core_check_processor_compat(void)
{
        int r;

        if (strncmp(cur_cpu_spec->platform, "ppc440", 6) == 0)
                r = 0;
        else
                r = -ENOTSUPP;

        return r;
}

int kvmppc_core_vcpu_setup(struct kvm_vcpu *vcpu)
{
        struct kvmppc_vcpu_44x *vcpu_44x = to_44x(vcpu);
        struct kvmppc_44x_tlbe *tlbe = &vcpu_44x->guest_tlb[0];
        int i;

        tlbe->tid = 0;
        tlbe->word0 = PPC44x_TLB_16M | PPC44x_TLB_VALID;
        tlbe->word1 = 0;
        tlbe->word2 = PPC44x_TLB_SX | PPC44x_TLB_SW | PPC44x_TLB_SR;

        tlbe++;
        tlbe->tid = 0;
        tlbe->word0 = 0xef600000 | PPC44x_TLB_4K | PPC44x_TLB_VALID;
        tlbe->word1 = 0xef600000;
        tlbe->word2 = PPC44x_TLB_SX | PPC44x_TLB_SW | PPC44x_TLB_SR
                      | PPC44x_TLB_I | PPC44x_TLB_G;

        /* Since the guest can directly access the timebase, it must know the
         * real timebase frequency. Accordingly, it must see the state of
         * CCR1[TCS]. */
        /* XXX CCR1 doesn't exist on all 440 SoCs. */
        vcpu->arch.ccr1 = mfspr(SPRN_CCR1);

        for (i = 0; i < ARRAY_SIZE(vcpu_44x->shadow_refs); i++)
                vcpu_44x->shadow_refs[i].gtlb_index = -1;

        vcpu->arch.cpu_type = KVM_CPU_440;
        vcpu->arch.pvr = mfspr(SPRN_PVR);

        return 0;
}

/* 'linear_address' is actually an encoding of AS|PID|EADDR . */
int kvmppc_core_vcpu_translate(struct kvm_vcpu *vcpu,
                               struct kvm_translation *tr)
{
        int index;
        gva_t eaddr;
        u8 pid;
        u8 as;

        eaddr = tr->linear_address;
        pid = (tr->linear_address >> 32) & 0xff;
        as = (tr->linear_address >> 40) & 0x1;

        index = kvmppc_44x_tlb_index(vcpu, eaddr, pid, as);
        if (index == -1) {
                tr->valid = 0;
                return 0;
        }

        tr->physical_address = kvmppc_mmu_xlate(vcpu, index, eaddr);
        /* XXX what does "writeable" and "usermode" even mean? */
        tr->valid = 1;

        return 0;
}

static int kvmppc_core_get_sregs_44x(struct kvm_vcpu *vcpu,
                                      struct kvm_sregs *sregs)
{
        return kvmppc_get_sregs_ivor(vcpu, sregs);
}

static int kvmppc_core_set_sregs_44x(struct kvm_vcpu *vcpu,
                                     struct kvm_sregs *sregs)
{
        return kvmppc_set_sregs_ivor(vcpu, sregs);
}

static int kvmppc_get_one_reg_44x(struct kvm_vcpu *vcpu, u64 id,
                                  union kvmppc_one_reg *val)
{
        return -EINVAL;
}

static int kvmppc_set_one_reg_44x(struct kvm_vcpu *vcpu, u64 id,
                                  union kvmppc_one_reg *val)
{
        return -EINVAL;
}

static struct kvm_vcpu *kvmppc_core_vcpu_create_44x(struct kvm *kvm,
                                                    unsigned int id)
{
        struct kvmppc_vcpu_44x *vcpu_44x;
        struct kvm_vcpu *vcpu;
        int err;

        vcpu_44x = kmem_cache_zalloc(kvm_vcpu_cache, GFP_KERNEL);
        if (!vcpu_44x) {
                err = -ENOMEM;
                goto out;
        }

        vcpu = &vcpu_44x->vcpu;
        err = kvm_vcpu_init(vcpu, kvm, id);
        if (err)
                goto free_vcpu;

        vcpu->arch.shared = (void*)__get_free_page(GFP_KERNEL|__GFP_ZERO);
        if (!vcpu->arch.shared)
                goto uninit_vcpu;

        return vcpu;

uninit_vcpu:
        kvm_vcpu_uninit(vcpu);
free_vcpu:
        kmem_cache_free(kvm_vcpu_cache, vcpu_44x);
out:
        return ERR_PTR(err);
}

static void kvmppc_core_vcpu_free_44x(struct kvm_vcpu *vcpu)
{
        struct kvmppc_vcpu_44x *vcpu_44x = to_44x(vcpu);

        free_page((unsigned long)vcpu->arch.shared);
        kvm_vcpu_uninit(vcpu);
        kmem_cache_free(kvm_vcpu_cache, vcpu_44x);
}

static int kvmppc_core_init_vm_44x(struct kvm *kvm)
{
        return 0;
}

static void kvmppc_core_destroy_vm_44x(struct kvm *kvm)
{
}

static struct kvmppc_ops kvm_ops_44x = {
        .get_sregs = kvmppc_core_get_sregs_44x,
        .set_sregs = kvmppc_core_set_sregs_44x,
        .get_one_reg = kvmppc_get_one_reg_44x,
        .set_one_reg = kvmppc_set_one_reg_44x,
        .vcpu_load   = kvmppc_core_vcpu_load_44x,
        .vcpu_put    = kvmppc_core_vcpu_put_44x,
        .vcpu_create = kvmppc_core_vcpu_create_44x,
        .vcpu_free   = kvmppc_core_vcpu_free_44x,
        .mmu_destroy  = kvmppc_mmu_destroy_44x,
        .init_vm = kvmppc_core_init_vm_44x,
        .destroy_vm = kvmppc_core_destroy_vm_44x,
        .emulate_op = kvmppc_core_emulate_op_44x,
        .emulate_mtspr = kvmppc_core_emulate_mtspr_44x,
        .emulate_mfspr = kvmppc_core_emulate_mfspr_44x,
};

static int __init kvmppc_44x_init(void)
{
        int r;

        r = kvmppc_booke_init();
        if (r)
                goto err_out;

        r = kvm_init(NULL, sizeof(struct kvmppc_vcpu_44x), 0, THIS_MODULE);
        if (r)
                goto err_out;
        kvm_ops_44x.owner = THIS_MODULE;
        kvmppc_pr_ops = &kvm_ops_44x;

err_out:
        return r;
}

static void __exit kvmppc_44x_exit(void)
{
        kvmppc_pr_ops = NULL;
        kvmppc_booke_exit();
}

module_init(kvmppc_44x_init);
module_exit(kvmppc_44x_exit);
MODULE_ALIAS_MISCDEV(KVM_MINOR);
MODULE_ALIAS("devname:kvm");