system/dev/display/intel-i915/gtt.h

// Copyright 2017 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#pragma once

#include <ddk/protocol/display-controller.h>
#include <fbl/unique_ptr.h>
#include <fbl/vector.h>
#include <hwreg/mmio.h>
#include <region-alloc/region-alloc.h>
#include <lib/zx/bti.h>
#include <lib/zx/vmo.h>

namespace i915 {

class Controller;
class Gtt;

class GttRegion {
public:
    explicit GttRegion(Gtt* gtt);
    ~GttRegion();

    void SetRotation(uint32_t rotation, const image_t& image);

    zx_status_t PopulateRegion(zx_handle_t vmo, uint64_t page_offset,
                               uint64_t length, bool writable = false);
    void ClearRegion(bool close_vmo);

    uint64_t base() const { return region_->base; }
    uint64_t size() const { return region_->size; }
private:
    fbl::unique_ptr<const RegionAllocator::Region> region_;
    Gtt* gtt_;

    fbl::Vector<zx::pmt> pmts_;
    uint32_t mapped_end_ = 0;
    // The region's current vmo. The region does not own the vmo handle; it
    // is up to the owner of the region to determine when the vmo should be
    // closed.
    zx_handle_t vmo_ = ZX_HANDLE_INVALID;

    bool is_rotated_;

    friend class Gtt;
};

class Gtt {
public:
    Gtt();
    ~Gtt();
    zx_status_t Init(Controller* controller);
    zx_status_t AllocRegion(uint32_t length,
                            uint32_t align_pow2, fbl::unique_ptr<GttRegion>* region_out);
    void SetupForMexec(uintptr_t stolen_fb, uint32_t length);

    uint64_t size() const { return gfx_mem_size_; }
private:
    Controller* controller_;

    uint64_t gfx_mem_size_;
    RegionAllocator region_allocator_;
    zx::vmo scratch_buffer_;
    zx::bti bti_;
    zx::pmt scratch_buffer_pmt_;
    zx_paddr_t scratch_buffer_paddr_ = 0;
    uint64_t min_contiguity_;

    friend class GttRegion;

    DISALLOW_COPY_ASSIGN_AND_MOVE(Gtt);
};

} // namespace i915