| 1 | /* |
| 2 | * Copyright 2010-2017 Intel Corporation. |
| 3 | * |
| 4 | * This program is free software; you can redistribute it and/or modify |
| 5 | * it under the terms of the GNU General Public License, version 2, |
| 6 | * as published by the Free Software Foundation. |
| 7 | * |
| 8 | * This program is distributed in the hope that it will be useful, |
| 9 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 10 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 11 | * General Public License for more details. |
| 12 | * |
| 13 | * Disclaimer: The codes contained in these modules may be specific to |
| 14 | * the Intel Software Development Platform codenamed Knights Ferry, |
| 15 | * and the Intel product codenamed Knights Corner, and are not backward |
| 16 | * compatible with other Intel products. Additionally, Intel will NOT |
| 17 | * support the codes or instruction set in future products. |
| 18 | * |
| 19 | * Intel offers no warranty of any kind regarding the code. This code is |
| 20 | * licensed on an "AS IS" basis and Intel is not obligated to provide |
| 21 | * any support, assistance, installation, training, or other services |
| 22 | * of any kind. Intel is also not obligated to provide any updates, |
| 23 | * enhancements or extensions. Intel specifically disclaims any warranty |
| 24 | * of merchantability, non-infringement, fitness for any particular |
| 25 | * purpose, and any other warranty. |
| 26 | * |
| 27 | * Further, Intel disclaims all liability of any kind, including but |
| 28 | * not limited to liability for infringement of any proprietary rights, |
| 29 | * relating to the use of the code, even if Intel is notified of the |
| 30 | * possibility of such liability. Except as expressly stated in an Intel |
| 31 | * license agreement provided with this code and agreed upon with Intel, |
| 32 | * no license, express or implied, by estoppel or otherwise, to any |
| 33 | * intellectual property rights is granted herein. |
| 34 | */ |
| 35 | |
| 36 | /* |
| 37 | Description: This is a generic ring buffer implementation to be used by |
| 38 | anyone who needs a ring buffer. The ring buffer is maipulated |
| 39 | using Read and Write functions. These functions perform all of |
| 40 | the necessary space checks and only complete the operation if |
| 41 | if the requested number of items can be read or written. A |
| 42 | return value of false indicates that either the ring buffer |
| 43 | contains less then the requested number of items (for Read) or |
| 44 | there isn't enough space left in the ring buffer (for Write). |
| 45 | */ |
| 46 | |
| 47 | #ifndef _MICHOST_RING_BUFFER_DEFINE |
| 48 | |
| 49 | #define _MICHOST_RING_BUFFER_DEFINE |
| 50 | |
| 51 | // |
| 52 | // Requirements: |
| 53 | // Ring base should be already aligned properly |
| 54 | // Ring size should be just multiple of the alignment size |
| 55 | // All packets should be at least multiple of 4 bytes for the purpose of padding |
| 56 | // |
| 57 | |
| 58 | #define RINGBUFFER_ALIGNMENT_SIZE 64 // in byte |
| 59 | |
| 60 | typedef struct _ringbuffer |
| 61 | { |
| 62 | uint8_t *ringbuff_ptr; |
| 63 | volatile uint32_t *readptr; // Points to the read offset |
| 64 | volatile uint32_t *writeptr; // Points to the write offset |
| 65 | uint32_t ringbuffsize; |
| 66 | uint32_t curr_readoffset; // cache it to improve performance. |
| 67 | uint32_t curr_writeoffset; // cache it to improve performance. |
| 68 | uint32_t old_readoffset; |
| 69 | uint32_t old_writeoffset; |
| 70 | } ringbuffer; |
| 71 | |
| 72 | // Commands common across all ring buffers |
| 73 | typedef enum _rb_cmdopcode |
| 74 | { |
| 75 | // note: don't use 0, because the ring buffer |
| 76 | // is initialized to a bunch of 0's that aren't really commands. |
| 77 | MIC_RBCT_ERROR = 0x0, // an error has occurred if encountered |
| 78 | MIC_RBCT_NOP, // Used to skip empty space in the ringbuffer. |
| 79 | MIC_RBCT_DMAEXEC, // DMA buffer to transfer/execute |
| 80 | MIC_RBCT_SHUTDOWN, // bus power-down eminent |
| 81 | MIC_RBCT_CREATESTDPROCESS, // Launches an executable on the ramdisk. |
| 82 | MIC_RBCT_CREATENATIVEPROCESS, // Launches a native process. |
| 83 | // NRFIX : not implemented. If native apps are launched by loading shared |
| 84 | // libraries(DLLs) into a standard stub app then this command goes away. |
| 85 | MIC_RBCT_DESTROYPROCESS, // Destroys a process. |
| 86 | MIC_RBCT_VIRTUALALLOC, // Creates a uOS virtual address range |
| 87 | MIC_RBCT_MAPHOSTMEMORY, // Used by implement host kernel mode driver services |
| 88 | MIC_RBCT_UNMAPHOSTMEMORY, // Unmaps host memory |
| 89 | MIC_RBCT_UOSESCAPE, // Used to pass uOS escapes from the host |
| 90 | MIC_RBCT_RESERVED1, // Reserved for future use |
| 91 | MIC_RBCT_RESERVED2, // Reserved for future use |
| 92 | MIC_RBCT_UPLOADSTDAPPLICATION, // Uploads a standard application to the uOS |
| 93 | MIC_RBCT_CREATEUOSRESOURCE, // Creates a DPT page cache |
| 94 | MIC_RBCT_DESTROYUOSRESOURCE, // Destroys a DPT page cache |
| 95 | MIC_RBCT_RESERVE_RING_BANDWIDTH_DBOX_TRAFFIC, // Reserves a ring bandwidth for DBOX traffic |
| 96 | |
| 97 | // Following commands are from MIC->Host (CRBT => CPU ring buffer.) |
| 98 | MIC_CRBT_LOG_INFO, // Host logs information sent by the uOS. |
| 99 | |
| 100 | // Always make these the last ones in the list |
| 101 | #if defined(MIC_DEBUG) || defined(ENABLE_GFXDEBUG) |
| 102 | MIC_RBCT_READPHYSICALMEMORY = 0x8000, // Used by debug tools to read memory on the device |
| 103 | MIC_RBCT_WRITEPHYSICALMEMORY, // Used by debug tools to write memory on the device |
| 104 | #endif // defined(MIC_DEBUG) || defined(ENABLE_GFXDEBUG) |
| 105 | MIC_RBCT_CMD_MAX // No valid OpCodes above this one |
| 106 | }ringbuff_cmdop; |
| 107 | |
| 108 | typedef struct _ringbuff_cmdhdr |
| 109 | { |
| 110 | ringbuff_cmdop opcode:16; |
| 111 | uint32_t size:16; |
| 112 | }ringbuff_cmdhdr; |
| 113 | |
| 114 | #ifdef __cplusplus |
| 115 | extern "C" { |
| 116 | #endif |
| 117 | |
| 118 | //--------------------------------- |
| 119 | // methods used by both |
| 120 | //--------------------------------- |
| 121 | // initialize cached ring buffer structure |
| 122 | void rb_initialize(ringbuffer* ringbuff, volatile uint32_t* readptr, |
| 123 | volatile uint32_t* writeptr, void *buff, const uint32_t size); |
| 124 | |
| 125 | //--------------------------------- |
| 126 | // writer-only methods |
| 127 | //--------------------------------- |
| 128 | // write a new command. Must follow with fence/MMIO, then RingBufferCommit() |
| 129 | int rb_write(ringbuffer* ringbuff, ringbuff_cmdhdr* cmd_header); |
| 130 | // After write(), do an mfence(), an MMIO write to serialize, then Commit() |
| 131 | void rb_commit(ringbuffer* ringbuff); |
| 132 | // used on power state change to reset cached pointers |
| 133 | void rb_reset(ringbuffer* ringbuff); |
| 134 | // used to determine the largest possible command that could be sent next |
| 135 | uint32_t rb_get_available_space(ringbuffer* ringbuff); |
| 136 | |
| 137 | // TODO: It may be more optimal to have "Reserve" function exposed to the client |
| 138 | // instead of requiring it to create a command that will be copied into the ring buffer. |
| 139 | |
| 140 | |
| 141 | //--------------------------------- |
| 142 | // reader-only methods |
| 143 | //--------------------------------- |
| 144 | // uses (updates) the cached read pointer to get the next command, so writer doesn't |
| 145 | // see the command as consumed |
| 146 | ringbuff_cmdhdr* rb_get_next_cmd(ringbuffer* ringbuff); |
| 147 | // updates the control block read pointer, which will be visible to the writer so it |
| 148 | // can re-use the space |
| 149 | void rb_update_readptr(ringbuffer* ringbuff, ringbuff_cmdhdr* cmd_header); |
| 150 | // reader skips all commands, updating its next read offset |
| 151 | void rb_skip_to_offset(ringbuffer* ringbuff, uint32_t new_readptr); |
| 152 | |
| 153 | // uOS used this method to determine if RingBuffer is empty or not before attempting |
| 154 | // to fetch command out of ring buffer If ringbuffer is empty, means uOS would have |
| 155 | // fetched it earlier. |
| 156 | uint32_t rb_empty(ringbuffer* ringbuff); |
| 157 | |
| 158 | // only used by host simulator |
| 159 | void rb_sync(ringbuffer* ringbuff); |
| 160 | |
| 161 | #ifdef __cplusplus |
| 162 | } |
| 163 | #endif |
| 164 | |
| 165 | #ifdef __LINUX_GPL__ |
| 166 | //============================================================================== |
| 167 | // FUNCTION: AlignLow |
| 168 | // |
| 169 | // DESCRIPTION: Returns trunk(in_data / in_granularity) * in_granularity |
| 170 | // |
| 171 | // PARAMETERS: |
| 172 | // in_data - Data to be aligned |
| 173 | // in_granularity - Alignment chunk size - must be a power of 2 |
| 174 | #if defined(__cplusplus) |
| 175 | template <typename TData> |
| 176 | #else // no C++ |
| 177 | #define TData uint64_t |
| 178 | #endif // if C++ |
| 179 | |
| 180 | static inline TData AlignLow(TData in_data, uintptr_t in_granularity) |
| 181 | { |
| 182 | TData mask = (TData)(in_granularity-1); // 64 -> 0x3f |
| 183 | |
| 184 | // floor to granularity |
| 185 | TData low = in_data & ~mask; |
| 186 | |
| 187 | return low; |
| 188 | } |
| 189 | |
| 190 | #if !defined(__cplusplus) |
| 191 | #undef TData |
| 192 | #endif // if no C++ |
| 193 | #endif // __LINUX_GPL_ |
| 194 | |
| 195 | #endif //_MICHOST_RING_BUFFER_DEFINE |