| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| */ |
| |
| /*! |
| * \file virtual_memory.h |
| * \brief The virtual memory manager for device simulation |
| */ |
| |
| #ifndef VTA_VMEM_VIRTUAL_MEMORY_H_ |
| #define VTA_VMEM_VIRTUAL_MEMORY_H_ |
| |
| #include <vta/driver.h> |
| #include <cstdint> |
| #include <type_traits> |
| #include <mutex> |
| #include <vector> |
| #include <map> |
| #include <unordered_map> |
| #include <memory> |
| |
| enum VMemCopyType { |
| kVirtualMemCopyFromHost = 0, |
| kVirtualMemCopyToHost = 1 |
| }; |
| |
| namespace vta { |
| namespace vmem { |
| |
| /*! |
| * \brief DRAM memory manager |
| * Implements simple paging to allow physical address translation. |
| */ |
| class VirtualMemoryManager { |
| public: |
| /*! |
| * \brief Get virtual address given physical address. |
| * \param phy_addr The simulator phyiscal address. |
| * \return The true virtual address; |
| */ |
| void* GetAddr(uint64_t phy_addr); |
| /*! |
| * \brief Get physical address |
| * \param buf The virtual address. |
| * \return The true physical address; |
| */ |
| vta_phy_addr_t GetPhyAddr(void* buf); |
| /*! |
| * \brief Allocate memory from manager |
| * \param size The size of memory |
| * \return The virtual address |
| */ |
| void* Alloc(size_t size); |
| /*! |
| * \brief Free the memory. |
| * \param size The size of memory |
| * \return The virtual address |
| */ |
| void Free(void* data); |
| /*! |
| * \brief Copy from the host memory to device memory (virtual). |
| * \param dst The device memory address (virtual) |
| * \param src The host memory address |
| * \param size The size of memory |
| */ |
| void MemCopyFromHost(void* dst, const void * src, size_t size); |
| /*! |
| * \brief Copy from the device memory (virtual) to host memory. |
| * \param dst The host memory address |
| * \param src The device memory address (virtual) |
| * \param size The size of memory |
| */ |
| void MemCopyToHost(void* dst, const void * src, size_t size); |
| static VirtualMemoryManager* Global(); |
| |
| private: |
| // The bits in page table |
| static constexpr vta_phy_addr_t kPageBits = VTA_PAGE_BITS; |
| // page size, also the maximum allocable size 16 K |
| static constexpr vta_phy_addr_t kPageSize = VTA_PAGE_BYTES; |
| /*! \brief A page in the DRAM */ |
| struct Page { |
| /*! \brief Data Type */ |
| using DType = typename std::aligned_storage<kPageSize, 256>::type; |
| /*! \brief Start location in page table */ |
| size_t ptable_begin; |
| /*! \brief The total number of pages */ |
| size_t num_pages; |
| /*! \brief Data */ |
| DType* data{nullptr}; |
| // construct a new page |
| explicit Page(size_t ptable_begin, size_t num_pages) |
| : ptable_begin(ptable_begin), num_pages(num_pages) { |
| data = new DType[num_pages]; |
| } |
| ~Page() { |
| delete [] data; |
| } |
| }; |
| // Internal lock |
| std::mutex mutex_; |
| // Physical address -> page |
| std::vector<Page*> ptable_; |
| // virtual addres -> page |
| std::unordered_map<void*, std::unique_ptr<Page> > pmap_; |
| // Free map |
| std::multimap<size_t, Page*> free_map_; |
| }; |
| |
| |
| } // namespace vmem |
| } // namespace vta |
| |
| #endif // VTA_VMEM_VIRTUAL_MEMORY_H_ |