/* SPDX-License-Identifier: GPL-2.0-only */
/*
 * Copyright (C) 2013 Red Hat
 * Author: Rob Clark <robdclark@gmail.com>
 */

#ifndef __MSM_MMU_H__
#define __MSM_MMU_H__

#include <linux/iommu.h>

struct msm_mmu_prealloc;
struct msm_mmu;
struct msm_gpu;

struct msm_mmu_funcs {
        void (*detach)(struct msm_mmu *mmu);
        void (*prealloc_count)(struct msm_mmu *mmu, struct msm_mmu_prealloc *p,
                               uint64_t iova, size_t len);
        int (*prealloc_allocate)(struct msm_mmu *mmu, struct msm_mmu_prealloc *p);
        void (*prealloc_cleanup)(struct msm_mmu *mmu, struct msm_mmu_prealloc *p);
        int (*map)(struct msm_mmu *mmu, uint64_t iova, struct sg_table *sgt,
                        size_t off, size_t len, int prot);
        int (*unmap)(struct msm_mmu *mmu, uint64_t iova, size_t len);
        void (*destroy)(struct msm_mmu *mmu);
        void (*set_stall)(struct msm_mmu *mmu, bool enable);
};

enum msm_mmu_type {
        MSM_MMU_GPUMMU,
        MSM_MMU_IOMMU,
        MSM_MMU_IOMMU_PAGETABLE,
};

/**
 * struct msm_mmu_prealloc - Tracking for pre-allocated pages for MMU updates.
 */
struct msm_mmu_prealloc {
        /** @count: Number of pages reserved. */
        uint32_t count;
        /** @ptr: Index of first unused page in @pages */
        uint32_t ptr;
        /**
         * @pages: Array of pages preallocated for MMU table updates.
         *
         * After a VM operation, there might be free pages remaining in this
         * array (since the amount allocated is a worst-case).  These are
         * returned to the pt_cache at mmu->prealloc_cleanup().
         */
        void **pages;
};

struct msm_mmu {
        const struct msm_mmu_funcs *funcs;
        struct device *dev;
        int (*handler)(void *arg, unsigned long iova, int flags, void *data);
        void *arg;
        enum msm_mmu_type type;

        /**
         * @prealloc: pre-allocated pages for pgtable
         *
         * Set while a VM_BIND job is running, serialized under
         * msm_gem_vm::mmu_lock.
         */
        struct msm_mmu_prealloc *prealloc;
};

static inline void msm_mmu_init(struct msm_mmu *mmu, struct device *dev,
                const struct msm_mmu_funcs *funcs, enum msm_mmu_type type)
{
        mmu->dev = dev;
        mmu->funcs = funcs;
        mmu->type = type;
}

struct msm_mmu *msm_iommu_new(struct device *dev, unsigned long quirks);
struct msm_mmu *msm_iommu_gpu_new(struct device *dev, struct msm_gpu *gpu, unsigned long quirks);
struct msm_mmu *msm_iommu_disp_new(struct device *dev, unsigned long quirks);

static inline void msm_mmu_set_fault_handler(struct msm_mmu *mmu, void *arg,
                int (*handler)(void *arg, unsigned long iova, int flags, void *data))
{
        mmu->arg = arg;
        mmu->handler = handler;
}

struct msm_mmu *msm_iommu_pagetable_create(struct msm_mmu *parent, bool kernel_managed);

int msm_iommu_pagetable_params(struct msm_mmu *mmu, phys_addr_t *ttbr,
                               int *asid);
int msm_iommu_pagetable_walk(struct msm_mmu *mmu, unsigned long iova, uint64_t ptes[4]);
struct iommu_domain_geometry *msm_iommu_get_geometry(struct msm_mmu *mmu);

#endif /* __MSM_MMU_H__ */