1/***********************license start*************** 2 * Copyright (c) 2003-2010 Cavium Inc. (support@cavium.com). All rights 3 * reserved. 4 * 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions are 8 * met: 9 * 10 * * Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 13 * * Redistributions in binary form must reproduce the above 14 * copyright notice, this list of conditions and the following 15 * disclaimer in the documentation and/or other materials provided 16 * with the distribution. 17 18 * * Neither the name of Cavium Inc. nor the names of 19 * its contributors may be used to endorse or promote products 20 * derived from this software without specific prior written 21 * permission. 22 23 * This Software, including technical data, may be subject to U.S. export control 24 * laws, including the U.S. Export Administration Act and its associated 25 * regulations, and may be subject to export or import regulations in other 26 * countries. 27 28 * TO THE MAXIMUM EXTENT PERMITTED BY LAW, THE SOFTWARE IS PROVIDED "AS IS" 29 * AND WITH ALL FAULTS AND CAVIUM INC. MAKES NO PROMISES, REPRESENTATIONS OR 30 * WARRANTIES, EITHER EXPRESS, IMPLIED, STATUTORY, OR OTHERWISE, WITH RESPECT TO 31 * THE SOFTWARE, INCLUDING ITS CONDITION, ITS CONFORMITY TO ANY REPRESENTATION OR 32 * DESCRIPTION, OR THE EXISTENCE OF ANY LATENT OR PATENT DEFECTS, AND CAVIUM 33 * SPECIFICALLY DISCLAIMS ALL IMPLIED (IF ANY) WARRANTIES OF TITLE, 34 * MERCHANTABILITY, NONINFRINGEMENT, FITNESS FOR A PARTICULAR PURPOSE, LACK OF 35 * VIRUSES, ACCURACY OR COMPLETENESS, QUIET ENJOYMENT, QUIET POSSESSION OR 36 * CORRESPONDENCE TO DESCRIPTION. THE ENTIRE RISK ARISING OUT OF USE OR 37 * PERFORMANCE OF THE SOFTWARE LIES WITH YOU. 38 ***********************license end**************************************/ 39 40 41 42 43 44 45 46/** 47 * @file 48 * 49 * Interface to the hardware work queue timers. 50 * 51`* <hr>$Revision: 70030 $<hr> 52 */ 53 54#ifndef __CVMX_TIM_H__ 55#define __CVMX_TIM_H__ 56 57#include "cvmx-clock.h" 58#include "cvmx-fpa.h" 59#include "cvmx-wqe.h" 60 61#include "executive-config.h" 62#ifdef CVMX_ENABLE_TIMER_FUNCTIONS 63#include "cvmx-config.h" 64#endif 65 66#ifdef __cplusplus 67extern "C" { 68#endif 69 70#define CVMX_TIM_NUM_TIMERS (OCTEON_IS_MODEL(OCTEON_CN68XX) ? 64 : 16) 71#define CVMX_TIM_NUM_BUCKETS 2048 72 73typedef enum 74{ 75 CVMX_TIM_STATUS_SUCCESS = 0, 76 CVMX_TIM_STATUS_NO_MEMORY = -1, 77 CVMX_TIM_STATUS_TOO_FAR_AWAY = -2, 78 CVMX_TIM_STATUS_BUSY = -3 79} cvmx_tim_status_t; 80 81/** 82 * Each timer bucket contains a list of work queue entries to 83 * schedule when the timer fires. The list is implemented as 84 * a linked list of blocks. Each block contains an array of 85 * work queue entries followed by a next block pointer. Since 86 * these blocks are dynamically allocated off of a hardware 87 * memory pool, there actual size isn't known compile time. 88 * The next block pointer is stored in the last 8 bytes of 89 * the memory block. 90 */ 91typedef struct cvmx_tim_entry_chunk 92{ 93 volatile uint64_t entries[0]; 94} cvmx_tim_entry_chunk_t; 95 96/** 97 * Each timer contains an array of buckets. Each bucket 98 * represents the list of work queue entries that should be 99 * scheduled when the timer fires. The first 3 entries are used 100 * byt the hardware. 101 */ 102typedef struct 103{ 104 volatile uint64_t first_chunk_addr; 105 volatile uint32_t num_entries; /**< Zeroed by HW after traversing list */ 106 volatile uint32_t chunk_remainder;/**< Zeroed by HW after traversing list */ 107 108 // the remaining 16 bytes are not touched by hardware 109 volatile cvmx_tim_entry_chunk_t *last_chunk; 110 uint64_t pad; 111} cvmx_tim_bucket_entry_t; 112 113/** 114 * Structure representing an individual timer. Each timer has 115 * a timer period, a memory management pool, and a list of 116 * buckets. 117 */ 118typedef struct 119{ 120 cvmx_tim_bucket_entry_t*bucket; /**< The timer buckets. Array of [CVMX_TIM_NUM_TIMERS][CVMX_TIM_NUM_BUCKETS] */ 121 uint64_t tick_cycles; /**< How long a bucket represents */ 122 uint64_t start_time; /**< Time the timer started in cycles */ 123 uint32_t bucket_shift; /**< How long a bucket represents in ms */ 124 uint32_t num_buckets; /**< How many buckets per wheel */ 125 uint32_t max_ticks; /**< maximum number of ticks allowed for timer */ 126} cvmx_tim_t; 127 128/** 129 * Structure used to store state information needed to delete 130 * an already scheduled timer entry. An instance of this 131 * structure must be passed to cvmx_tim_add_entry in order 132 * to be able to delete an entry later with 133 * cvmx_tim_delete_entry. 134 * 135 * NOTE: This structure should be considered opaque by the application, 136 * and the application should not access its members 137 */ 138typedef struct 139{ 140 uint64_t commit_cycles; /**< After this time the timer can't be changed */ 141 uint64_t * timer_entry_ptr;/**< Where the work entry is. Zero this 142 location to delete the entry */ 143} cvmx_tim_delete_t; 144 145/** 146 * Global structure holding the state of all timers. 147 */ 148extern cvmx_tim_t cvmx_tim; 149 150 151 152 153#ifdef CVMX_ENABLE_TIMER_FUNCTIONS 154/** 155 * Setup a timer for use. Must be called before the timer 156 * can be used. 157 * 158 * @param tick Time between each bucket in microseconds. This must not be 159 * smaller than 1024/(clock frequency in MHz). 160 * @param max_ticks The maximum number of ticks the timer must be able 161 * to schedule in the future. There are guaranteed to be enough 162 * timer buckets such that: 163 * number of buckets >= max_ticks. 164 * @return Zero on success. Negative on error. Failures are possible 165 * if the number of buckets needed is too large or memory 166 * allocation fails for creating the buckets. 167 */ 168int cvmx_tim_setup(uint64_t tick, uint64_t max_ticks); 169#endif 170 171/** 172 * Start the hardware timer processing 173 */ 174extern void cvmx_tim_start(void); 175 176 177/** 178 * Stop the hardware timer processing. Timers stay configured. 179 */ 180extern void cvmx_tim_stop(void); 181 182 183/** 184 * Stop the timer. After this the timer must be setup again 185 * before use. 186 */ 187#ifdef CVMX_ENABLE_TIMER_FUNCTIONS 188extern void cvmx_tim_shutdown(void); 189#endif 190 191#ifdef CVMX_ENABLE_TIMER_FUNCTIONS 192/** 193 * Add a work queue entry to the timer. 194 * 195 * @param work_entry Work queue entry to add. 196 * @param ticks_from_now 197 * @param delete_info 198 * Optional pointer where to store information needed to 199 * delete the timer entry. If non NULL information needed 200 * to delete the timer entry before it fires is stored here. 201 * If you don't need to be able to delete the timer, pass 202 * NULL. 203 * @return Result return code 204 */ 205static inline cvmx_tim_status_t cvmx_tim_add_entry(cvmx_wqe_t *work_entry, uint64_t ticks_from_now, cvmx_tim_delete_t *delete_info) 206{ 207 cvmx_tim_bucket_entry_t* work_bucket_ptr; 208 uint64_t work_bucket; 209 volatile uint64_t * tim_entry_ptr; /* pointer to wqe address in timer chunk */ 210 uint64_t entries_per_chunk; 211 212 const uint64_t cycles = cvmx_clock_get_count(CVMX_CLOCK_TIM); /* Get our reference time early for accuracy */ 213 const uint64_t core_num = cvmx_get_core_num(); /* One timer per processor, so use this to select */ 214 215 /* Make sure the specified time won't wrap our bucket list */ 216 if (ticks_from_now > cvmx_tim.max_ticks) 217 { 218 cvmx_dprintf("cvmx_tim_add_entry: Tried to schedule work too far away.\n"); 219 return CVMX_TIM_STATUS_TOO_FAR_AWAY; 220 } 221 222 /* Since we have no way to synchronize, we can't update a timer that is 223 being used by the hardware. Two buckets forward should be safe */ 224 if (ticks_from_now < 2) 225 { 226 cvmx_dprintf("cvmx_tim_add_entry: Tried to schedule work too soon. Delaying it.\n"); 227 ticks_from_now = 2; 228 } 229 230 /* Get the bucket this work queue entry should be in. Remember the bucket 231 array is circular */ 232 work_bucket = (((ticks_from_now * cvmx_tim.tick_cycles) + cycles - cvmx_tim.start_time) 233 >> cvmx_tim.bucket_shift); 234 235 work_bucket_ptr = cvmx_tim.bucket + core_num * cvmx_tim.num_buckets + (work_bucket & (cvmx_tim.num_buckets - 1)); 236 entries_per_chunk = (CVMX_FPA_TIMER_POOL_SIZE/8 - 1); 237 238 /* Check if we have room to add this entry into the existing list */ 239 if (work_bucket_ptr->chunk_remainder) 240 { 241 /* Adding the work entry to the end of the existing list */ 242 tim_entry_ptr = &(work_bucket_ptr->last_chunk->entries[entries_per_chunk - work_bucket_ptr->chunk_remainder]); 243 *tim_entry_ptr = cvmx_ptr_to_phys(work_entry); 244 work_bucket_ptr->chunk_remainder--; 245 work_bucket_ptr->num_entries++; 246 } 247 else 248 { 249 /* Current list is either completely empty or completely full. We need 250 to allocate a new chunk for storing this work entry */ 251 cvmx_tim_entry_chunk_t *new_chunk = (cvmx_tim_entry_chunk_t *)cvmx_fpa_alloc(CVMX_FPA_TIMER_POOL); 252 if (new_chunk == NULL) 253 { 254 cvmx_dprintf("cvmx_tim_add_entry: Failed to allocate memory for new chunk.\n"); 255 return CVMX_TIM_STATUS_NO_MEMORY; 256 } 257 258 /* Does a chunk currently exist? We have to check num_entries since 259 the hardware doesn't NULL out the chunk pointers on free */ 260 if (work_bucket_ptr->num_entries) 261 { 262 /* This chunk must be appended to an existing list by putting 263 ** its address in the last spot of the existing chunk. */ 264 work_bucket_ptr->last_chunk->entries[entries_per_chunk] = cvmx_ptr_to_phys(new_chunk); 265 work_bucket_ptr->num_entries++; 266 } 267 else 268 { 269 /* This is the very first chunk. Add it */ 270 work_bucket_ptr->first_chunk_addr = cvmx_ptr_to_phys(new_chunk); 271 work_bucket_ptr->num_entries = 1; 272 } 273 work_bucket_ptr->last_chunk = new_chunk; 274 work_bucket_ptr->chunk_remainder = entries_per_chunk - 1; 275 tim_entry_ptr = &(new_chunk->entries[0]); 276 *tim_entry_ptr = cvmx_ptr_to_phys(work_entry); 277 } 278 279 /* If the user supplied a delete info structure then fill it in */ 280 if (delete_info) 281 { 282 /* It would be very bad to delete a timer entry after, or during the 283 timer's processing. During the processing could yield unpredicatable 284 results, but after would always be bad. Modifying the entry after 285 processing means we would be changing data in a buffer that has been 286 freed, and possible allocated again. For this reason we store a 287 commit cycle count in the delete structure. If we are after this 288 count we will refuse to delete the timer entry. */ 289 delete_info->commit_cycles = cycles + (ticks_from_now - 2) * cvmx_tim.tick_cycles; 290 delete_info->timer_entry_ptr = (uint64_t *)tim_entry_ptr; /* Cast to non-volatile type */ 291 } 292 293 CVMX_SYNCWS; /* Make sure the hardware timer unit can access valid data from L2 */ 294 295 return CVMX_TIM_STATUS_SUCCESS; 296} 297#endif 298 299 300/** 301 * Delete a timer entry scheduled using cvmx_tim_add_entry. 302 * Deleting a timer will fail if it has already triggered or 303 * might be in progress. The actual state of the work queue 304 * entry isn't changed. You need to dispose of it properly. 305 * 306 * @param delete_info 307 * Structure passed to cvmx_tim_add_entry to store the 308 * information needed to delete a timer entry. 309 * @return CVMX_TIM_STATUS_BUSY if the timer was not deleted, otherwise 310 * CVMX_TIM_STATUS_SUCCESS. 311 */ 312static inline cvmx_tim_status_t cvmx_tim_delete_entry(cvmx_tim_delete_t *delete_info) 313{ 314 const uint64_t cycles = cvmx_clock_get_count(CVMX_CLOCK_TIM); 315 316 if ((int64_t)(cycles - delete_info->commit_cycles) < 0) 317 { 318 /* Timer is far enough away. Safe to delete */ 319 *delete_info->timer_entry_ptr = 0; 320 return CVMX_TIM_STATUS_SUCCESS; 321 } 322 else 323 { 324 /* Timer is passed the commit time. It cannot be stopped */ 325 return CVMX_TIM_STATUS_BUSY; 326 } 327} 328 329#ifdef __cplusplus 330} 331#endif 332 333#endif // __CVMX_TIM_H__ 334