/*
 * ARM SMMU Support
 *
 * Copyright (C) 2015-2016 Broadcom Corporation
 * Copyright (c) 2017 Red Hat, Inc.
 * Written by Prem Mallappa, Eric Auger
 *
 * 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.
 *
 */

#ifndef HW_ARM_SMMU_COMMON_H
#define HW_ARM_SMMU_COMMON_H

#include "hw/sysbus.h"
#include "hw/pci/pci.h"

#define SMMU_PCI_BUS_MAX      256
#define SMMU_PCI_DEVFN_MAX    256
#define SMMU_PCI_DEVFN(sid)   (sid & 0xFF)

#define SMMU_MAX_VA_BITS      48

/*
 * Page table walk error types
 */
typedef enum {
    SMMU_PTW_ERR_NONE,
    SMMU_PTW_ERR_WALK_EABT,   /* Translation walk external abort */
    SMMU_PTW_ERR_TRANSLATION, /* Translation fault */
    SMMU_PTW_ERR_ADDR_SIZE,   /* Address Size fault */
    SMMU_PTW_ERR_ACCESS,      /* Access fault */
    SMMU_PTW_ERR_PERMISSION,  /* Permission fault */
} SMMUPTWEventType;

typedef struct SMMUPTWEventInfo {
    SMMUPTWEventType type;
    dma_addr_t addr; /* fetched address that induced an abort, if any */
} SMMUPTWEventInfo;

typedef struct SMMUTransTableInfo {
    bool disabled;             /* is the translation table disabled? */
    uint64_t ttb;              /* TT base address */
    uint8_t tsz;               /* input range, ie. 2^(64 -tsz)*/
    uint8_t granule_sz;        /* granule page shift */
} SMMUTransTableInfo;

/*
 * Generic structure populated by derived SMMU devices
 * after decoding the configuration information and used as
 * input to the page table walk
 */
typedef struct SMMUTransCfg {
    int stage;                 /* translation stage */
    bool aa64;                 /* arch64 or aarch32 translation table */
    bool disabled;             /* smmu is disabled */
    bool bypassed;             /* translation is bypassed */
    bool aborted;              /* translation is aborted */
    uint64_t ttb;              /* TT base address */
    uint8_t oas;               /* output address width */
    uint8_t tbi;               /* Top Byte Ignore */
    uint16_t asid;
    SMMUTransTableInfo tt[2];
    uint32_t iotlb_hits;       /* counts IOTLB hits for this asid */
    uint32_t iotlb_misses;     /* counts IOTLB misses for this asid */
} SMMUTransCfg;

typedef struct SMMUDevice {
    void               *smmu;
    PCIBus             *bus;
    int                devfn;
    IOMMUMemoryRegion  iommu;
    AddressSpace       as;
    uint32_t           cfg_cache_hits;
    uint32_t           cfg_cache_misses;
    QLIST_ENTRY(SMMUDevice) next;
} SMMUDevice;

typedef struct SMMUPciBus {
    PCIBus       *bus;
    SMMUDevice   *pbdev[0]; /* Parent array is sparse, so dynamically alloc */
} SMMUPciBus;

typedef struct SMMUIOTLBKey {
    uint64_t iova;
    uint16_t asid;
} SMMUIOTLBKey;

typedef struct SMMUState {
    /* <private> */
    SysBusDevice  dev;
    const char *mrtypename;
    MemoryRegion iomem;

    GHashTable *smmu_pcibus_by_busptr;
    GHashTable *configs; /* cache for configuration data */
    GHashTable *iotlb;
    SMMUPciBus *smmu_pcibus_by_bus_num[SMMU_PCI_BUS_MAX];
    PCIBus *pci_bus;
    QLIST_HEAD(, SMMUDevice) devices_with_notifiers;
    uint8_t bus_num;
    PCIBus *primary_bus;
} SMMUState;

typedef struct {
    /* <private> */
    SysBusDeviceClass parent_class;

    /*< public >*/

    DeviceRealize parent_realize;

} SMMUBaseClass;

#define TYPE_ARM_SMMU "arm-smmu"
#define ARM_SMMU(obj) OBJECT_CHECK(SMMUState, (obj), TYPE_ARM_SMMU)
#define ARM_SMMU_CLASS(klass)                                    \
    OBJECT_CLASS_CHECK(SMMUBaseClass, (klass), TYPE_ARM_SMMU)
#define ARM_SMMU_GET_CLASS(obj)                              \
    OBJECT_GET_CLASS(SMMUBaseClass, (obj), TYPE_ARM_SMMU)

/* Return the SMMUPciBus handle associated to a PCI bus number */
SMMUPciBus *smmu_find_smmu_pcibus(SMMUState *s, uint8_t bus_num);

/* Return the stream ID of an SMMU device */
static inline uint16_t smmu_get_sid(SMMUDevice *sdev)
{
    return PCI_BUILD_BDF(pci_bus_num(sdev->bus), sdev->devfn);
}

/**
 * smmu_ptw - Perform the page table walk for a given iova / access flags
 * pair, according to @cfg translation config
 */
int smmu_ptw(SMMUTransCfg *cfg, dma_addr_t iova, IOMMUAccessFlags perm,
             IOMMUTLBEntry *tlbe, SMMUPTWEventInfo *info);

/**
 * select_tt - compute which translation table shall be used according to
 * the input iova and translation config and return the TT specific info
 */
SMMUTransTableInfo *select_tt(SMMUTransCfg *cfg, dma_addr_t iova);

/* Return the iommu mr associated to @sid, or NULL if none */
IOMMUMemoryRegion *smmu_iommu_mr(SMMUState *s, uint32_t sid);

#define SMMU_IOTLB_MAX_SIZE 256

void smmu_iotlb_inv_all(SMMUState *s);
void smmu_iotlb_inv_asid(SMMUState *s, uint16_t asid);
void smmu_iotlb_inv_iova(SMMUState *s, uint16_t asid, dma_addr_t iova);

/* Unmap the range of all the notifiers registered to any IOMMU mr */
void smmu_inv_notifiers_all(SMMUState *s);

/* Unmap the range of all the notifiers registered to @mr */
void smmu_inv_notifiers_mr(IOMMUMemoryRegion *mr);

#endif /* HW_ARM_SMMU_COMMON_H */