1 /* SPDX-License-Identifier: (BSD-3-Clause OR LGPL-2.1) 2 * Copyright(c) 2010-2013 Intel Corporation. 3 * Copyright(c) 2013-2017 Wind River Systems, Inc. 4 */ 5 6 #ifndef _RTE_AVP_FIFO_H_ 7 #define _RTE_AVP_FIFO_H_ 8 9 #include "rte_avp_common.h" 10 11 #ifdef __KERNEL__ 12 /* Write memory barrier for kernel compiles */ 13 #define AVP_WMB() smp_wmb() 14 /* Read memory barrier for kernel compiles */ 15 #define AVP_RMB() smp_rmb() 16 #else 17 /* Write memory barrier for userspace compiles */ 18 #define AVP_WMB() rte_wmb() 19 /* Read memory barrier for userspace compiles */ 20 #define AVP_RMB() rte_rmb() 21 #endif 22 23 #ifndef __KERNEL__ 24 #include <rte_debug.h> 25 26 #ifdef __cplusplus 27 extern "C" { 28 #endif 29 30 /** 31 * Initializes the avp fifo structure 32 */ 33 static inline void 34 avp_fifo_init(struct rte_avp_fifo *fifo, unsigned int size) 35 { 36 /* Ensure size is power of 2 */ 37 if (size & (size - 1)) 38 rte_panic("AVP fifo size must be power of 2\n"); 39 40 fifo->write = 0; 41 fifo->read = 0; 42 fifo->len = size; 43 fifo->elem_size = sizeof(void *); 44 } 45 #endif 46 47 /** 48 * Adds num elements into the fifo. Return the number actually written 49 */ 50 static inline unsigned 51 avp_fifo_put(struct rte_avp_fifo *fifo, void **data, unsigned int num) 52 { 53 unsigned int i = 0; 54 unsigned int fifo_write = fifo->write; 55 unsigned int fifo_read = fifo->read; 56 unsigned int new_write = fifo_write; 57 58 for (i = 0; i < num; i++) { 59 new_write = (new_write + 1) & (fifo->len - 1); 60 61 if (new_write == fifo_read) 62 break; 63 fifo->buffer[fifo_write] = data[i]; 64 fifo_write = new_write; 65 } 66 AVP_WMB(); 67 fifo->write = fifo_write; 68 return i; 69 } 70 71 /** 72 * Get up to num elements from the fifo. Return the number actually read 73 */ 74 static inline unsigned int 75 avp_fifo_get(struct rte_avp_fifo *fifo, void **data, unsigned int num) 76 { 77 unsigned int i = 0; 78 unsigned int new_read = fifo->read; 79 unsigned int fifo_write = fifo->write; 80 81 if (new_read == fifo_write) 82 return 0; /* empty */ 83 84 for (i = 0; i < num; i++) { 85 if (new_read == fifo_write) 86 break; 87 88 data[i] = fifo->buffer[new_read]; 89 new_read = (new_read + 1) & (fifo->len - 1); 90 } 91 AVP_RMB(); 92 fifo->read = new_read; 93 return i; 94 } 95 96 /** 97 * Get the num of elements in the fifo 98 */ 99 static inline unsigned int 100 avp_fifo_count(struct rte_avp_fifo *fifo) 101 { 102 return (fifo->len + fifo->write - fifo->read) & (fifo->len - 1); 103 } 104 105 /** 106 * Get the num of available elements in the fifo 107 */ 108 static inline unsigned int 109 avp_fifo_free_count(struct rte_avp_fifo *fifo) 110 { 111 return (fifo->read - fifo->write - 1) & (fifo->len - 1); 112 } 113 114 #ifdef __cplusplus 115 } 116 #endif 117 118 #endif /* _RTE_AVP_FIFO_H_ */ 119