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   1 /******************************************************************************
   2 *
   3 * Copyright (C) 2010 - 2015 Xilinx, Inc.  All rights reserved.
   4 *
   5 * Permission is hereby granted, free of charge, to any person obtaining a copy
   6 * of this software and associated documentation files (the "Software"), to deal
   7 * in the Software without restriction, including without limitation the rights
   8 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
   9 * copies of the Software, and to permit persons to whom the Software is
  10 * furnished to do so, subject to the following conditions:
  11 *
  12 * The above copyright notice and this permission notice shall be included in
  13 * all copies or substantial portions of the Software.
  14 *
  15 * Use of the Software is limited solely to applications:
  16 * (a) running on a Xilinx device, or
  17 * (b) that interact with a Xilinx device through a bus or interconnect.
  18 *
  19 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  20 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  21 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
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  23 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF
  24 * OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  25 * SOFTWARE.
  26 *
  27 * Except as contained in this notice, the name of the Xilinx shall not be used
  28 * in advertising or otherwise to promote the sale, use or other dealings in
  29 * this Software without prior written authorization from Xilinx.
  30 *
  31 ******************************************************************************/
  32 /*****************************************************************************/
  33 /**
  34 *
  35 * @file xttcps.c
  36 * @addtogroup ttcps_v3_0
  37 * @{
  38 *
  39 * This file contains the implementation of the XTtcPs driver. This driver
  40 * controls the operation of one timer counter in the Triple Timer Counter (TTC)
  41 * module in the Ps block. Refer to xttcps.h for more detailed description
  42 * of the driver.
  43 *
  44 * <pre>
  45 * MODIFICATION HISTORY:
  46 *
  47 * Ver   Who    Date     Changes
  48 * ----- ------ -------- -------------------------------------------------
  49 * 1.00a drg/jz 01/21/10 First release
  50 * 3.00  kvn    02/13/15 Modified code for MISRA-C:2012 compliance.
  51 * 3.01  pkp        01/30/16 Modified XTtcPs_CfgInitialize to add XTtcps_Stop
  52 *                                               to stop the timer before configuring
  53 *
  54 * </pre>
  55 *
  56 ******************************************************************************/
  57
  58 /***************************** Include Files *********************************/
  59
  60 #include "xttcps.h"
  61
  62 /************************** Constant Definitions *****************************/
  63
  64 /**************************** Type Definitions *******************************/
  65
  66 /***************** Macros (Inline Functions) Definitions *********************/
  67
  68 /************************** Function Prototypes ******************************/
  69
  70 /************************** Variable Definitions *****************************/
  71
  72
  73 /*****************************************************************************/
  74 /**
  75 *
  76 * Initializes a specific XTtcPs instance such that the driver is ready to use.
  77 * This function initializes a single timer counter in the triple timer counter
  78 * function block.
  79 *
  80 * The state of the device after initialization is:
  81 *  - Overflow Mode
  82 *  - Internal (pclk) selected
  83 *  - Counter disabled
  84 *  - All Interrupts disabled
  85 *  - Output waveforms disabled
  86 *
  87 * @param        InstancePtr is a pointer to the XTtcPs instance.
  88 * @param        ConfigPtr is a reference to a structure containing information
  89 *               about a specific TTC device.
  90 * @param        EffectiveAddr is the device base address in the virtual memory
  91 *               address space. The caller is responsible for keeping the address
  92 *               mapping from EffectiveAddr to the device physical base address
  93 *               unchanged once this function is invoked. Unexpected errors may
  94 *               occur if the address mapping changes after this function is
  95 *               called. If address translation is not used, then use
  96 *               ConfigPtr->BaseAddress for this parameter, passing the physical
  97 *               address instead.
  98 *
  99 * @return
 100 *
 101 *               - XST_SUCCESS if the initialization is successful.
 102 *               - XST_DEVICE_IS_STARTED if the device is started. It must be
 103 *                 stopped to re-initialize.
 104 *
 105 * @note         Device has to be stopped first to call this function to
 106 *               initialize it.
 107 *
 108 ******************************************************************************/
 109 s32 XTtcPs_CfgInitialize(XTtcPs *InstancePtr, XTtcPs_Config *ConfigPtr,
 110                               u32 EffectiveAddr)
 111 {
 112         s32 Status;
 113         u32 IsStartResult;
 114         /*
 115          * Assert to validate input arguments.
 116          */
 117         Xil_AssertNonvoid(InstancePtr != NULL);
 118         Xil_AssertNonvoid(ConfigPtr != NULL);
 119
 120         /*
 121          * Set some default values
 122          */
 123         InstancePtr->Config.DeviceId = ConfigPtr->DeviceId;
 124         InstancePtr->Config.BaseAddress = EffectiveAddr;
 125         InstancePtr->Config.InputClockHz = ConfigPtr->InputClockHz;
 126
 127         IsStartResult = XTtcPs_IsStarted(InstancePtr);
 128         /*
 129          * If the timer counter has already started, return an error
 130          * Device should be stopped first.
 131          */
 132         if(IsStartResult == (u32)TRUE) {
 133                 Status = XST_DEVICE_IS_STARTED;
 134         } else {
 135
 136                 /*
 137                  * stop the timer before configuring
 138                  */
 139                 XTtcPs_Stop(InstancePtr);
 140                 /*
 141                  * Reset the count control register to it's default value.
 142                  */
 143                 XTtcPs_WriteReg(InstancePtr->Config.BaseAddress,
 144                                   XTTCPS_CNT_CNTRL_OFFSET,
 145                                   XTTCPS_CNT_CNTRL_RESET_VALUE);
 146
 147                 /*
 148                  * Reset the rest of the registers to the default values.
 149                  */
 150                 XTtcPs_WriteReg(InstancePtr->Config.BaseAddress,
 151                                   XTTCPS_CLK_CNTRL_OFFSET, 0x00U);
 152                 XTtcPs_WriteReg(InstancePtr->Config.BaseAddress,
 153                                   XTTCPS_INTERVAL_VAL_OFFSET, 0x00U);
 154                 XTtcPs_WriteReg(InstancePtr->Config.BaseAddress,
 155                                   XTTCPS_MATCH_1_OFFSET, 0x00U);
 156                 XTtcPs_WriteReg(InstancePtr->Config.BaseAddress,
 157                                   XTTCPS_MATCH_2_OFFSET, 0x00U);
 158                 XTtcPs_WriteReg(InstancePtr->Config.BaseAddress,
 159                                   XTTCPS_MATCH_2_OFFSET, 0x00U);
 160                 XTtcPs_WriteReg(InstancePtr->Config.BaseAddress,
 161                                   XTTCPS_IER_OFFSET, 0x00U);
 162                 XTtcPs_WriteReg(InstancePtr->Config.BaseAddress,
 163                                   XTTCPS_ISR_OFFSET, XTTCPS_IXR_ALL_MASK);
 164
 165                 InstancePtr->IsReady = XIL_COMPONENT_IS_READY;
 166
 167                 /*
 168                  * Reset the counter value
 169                  */
 170                 XTtcPs_ResetCounterValue(InstancePtr);
 171                 Status = XST_SUCCESS;
 172         }
 173         return Status;
 174 }
 175
 176 /*****************************************************************************/
 177 /**
 178 *
 179 * This function is used to set the match registers. There are three match
 180 * registers.
 181 *
 182 * The match 0 register is special. If the waveform output mode is enabled, the
 183 * waveform will change polarity when the count matches the value in the match 0
 184 * register. The polarity of the waveform output can also be set using the
 185 * XTtcPs_SetOptions() function.
 186 *
 187 * @param        InstancePtr is a pointer to the XTtcPs instance.
 188 * @param        MatchIndex is the index to the match register to be set.
 189 *               Valid values are 0, 1, or 2.
 190 * @param        Value is the 16-bit value to be set in the match register.
 191 *
 192 * @return       None
 193 *
 194 * @note         None
 195 *
 196 ****************************************************************************/
 197 void XTtcPs_SetMatchValue(XTtcPs *InstancePtr, u8 MatchIndex, u16 Value)
 198 {
 199         /*
 200          * Assert to validate input arguments.
 201          */
 202         Xil_AssertVoid(InstancePtr != NULL);
 203         Xil_AssertVoid(InstancePtr->IsReady == XIL_COMPONENT_IS_READY);
 204         Xil_AssertVoid(MatchIndex < (u8)XTTCPS_NUM_MATCH_REG);
 205
 206         /*
 207          * Write the value to the correct match register with MatchIndex
 208          */
 209         XTtcPs_WriteReg(InstancePtr->Config.BaseAddress,
 210                           XTtcPs_Match_N_Offset(MatchIndex), Value);
 211 }
 212
 213 /*****************************************************************************/
 214 /**
 215 *
 216 * This function is used to get the value of the match registers. There are
 217 * three match registers.
 218 *
 219 * @param        InstancePtr is a pointer to the XTtcPs instance.
 220 * @param        MatchIndex is the index to the match register to be set.
 221 *               Valid values are 0, 1, or 2.
 222 *
 223 * @return       None
 224 *
 225 * @note         None
 226 *
 227 ****************************************************************************/
 228 u16 XTtcPs_GetMatchValue(XTtcPs *InstancePtr, u8 MatchIndex)
 229 {
 230         u32 MatchReg;
 231
 232         /*
 233          * Assert to validate input arguments.
 234          */
 235         Xil_AssertNonvoid(InstancePtr != NULL);
 236         Xil_AssertNonvoid(InstancePtr->IsReady == XIL_COMPONENT_IS_READY);
 237         Xil_AssertNonvoid(MatchIndex < XTTCPS_NUM_MATCH_REG);
 238
 239         MatchReg = XTtcPs_ReadReg(InstancePtr->Config.BaseAddress,
 240                             XTtcPs_Match_N_Offset(MatchIndex));
 241
 242         return (u16) MatchReg;
 243 }
 244
 245 /*****************************************************************************/
 246 /**
 247 *
 248 * This function sets the prescaler enable bit and if needed sets the prescaler
 249 * bits in the control register.
 250 *
 251 * @param        InstancePtr is a pointer to the XTtcPs instance.
 252 * @param        PrescalerValue is a number from 0-16 that sets the prescaler
 253 *               to use.
 254 *               If the parameter is 0 - 15, use a prescaler on the clock of
 255 *               2^(PrescalerValue+1), or 2-65536.
 256 *               If the parameter is XTTCPS_CLK_CNTRL_PS_DISABLE, do not use a
 257 *               prescaler.
 258 *
 259 * @return       None
 260 *
 261 * @note         None
 262 *
 263 ****************************************************************************/
 264 void XTtcPs_SetPrescaler(XTtcPs *InstancePtr, u8 PrescalerValue)
 265 {
 266         u32 ClockReg;
 267
 268         /*
 269          * Assert to validate input arguments.
 270          */
 271         Xil_AssertVoid(InstancePtr != NULL);
 272         Xil_AssertVoid(InstancePtr->IsReady == XIL_COMPONENT_IS_READY);
 273         Xil_AssertVoid(PrescalerValue <= XTTCPS_CLK_CNTRL_PS_DISABLE);
 274
 275         /*
 276          * Read the clock control register
 277          */
 278         ClockReg = XTtcPs_ReadReg(InstancePtr->Config.BaseAddress,
 279                            XTTCPS_CLK_CNTRL_OFFSET);
 280
 281         /*
 282          * Clear all of the prescaler control bits in the register
 283          */
 284         ClockReg &=
 285                 ~(XTTCPS_CLK_CNTRL_PS_VAL_MASK | XTTCPS_CLK_CNTRL_PS_EN_MASK);
 286
 287         if (PrescalerValue < XTTCPS_CLK_CNTRL_PS_DISABLE) {
 288                 /*
 289                  * Set the prescaler value and enable prescaler
 290                  */
 291                 ClockReg |= (u32)(((u32)PrescalerValue << (u32)XTTCPS_CLK_CNTRL_PS_VAL_SHIFT) &
 292                         (u32)XTTCPS_CLK_CNTRL_PS_VAL_MASK);
 293                 ClockReg |= (u32)XTTCPS_CLK_CNTRL_PS_EN_MASK;
 294         }
 295
 296         /*
 297          * Write the register with the new values.
 298          */
 299         XTtcPs_WriteReg(InstancePtr->Config.BaseAddress,
 300                           XTTCPS_CLK_CNTRL_OFFSET, ClockReg);
 301 }
 302
 303 /*****************************************************************************/
 304 /**
 305 *
 306 * This function gets the input clock prescaler
 307 *
 308 * @param        InstancePtr is a pointer to the XTtcPs instance.
 309 *
 310 * <pre>
 311 * @return       The value(n) from which the prescalar value is calculated
 312 *               as 2^(n+1). Some example values are given below :
 313 *
 314 *       Value           Prescaler
 315 *       0               2
 316 *       1               4
 317 *       N               2^(n+1)
 318 *       15              65536
 319 *       16              1
 320 * </pre>
 321 *
 322 * @note         None.
 323 *
 324 ****************************************************************************/
 325 u8 XTtcPs_GetPrescaler(XTtcPs *InstancePtr)
 326 {
 327         u8 Status;
 328         u32 ClockReg;
 329
 330         /*
 331          * Assert to validate input arguments.
 332          */
 333         Xil_AssertNonvoid(InstancePtr != NULL);
 334         Xil_AssertNonvoid(InstancePtr->IsReady == XIL_COMPONENT_IS_READY);
 335
 336         /*
 337          * Read the clock control register
 338          */
 339         ClockReg = XTtcPs_ReadReg(InstancePtr->Config.BaseAddress,
 340                                     XTTCPS_CLK_CNTRL_OFFSET);
 341
 342         if (0 == (ClockReg & XTTCPS_CLK_CNTRL_PS_EN_MASK)) {
 343                 /*
 344                  * Prescaler is disabled. Return the correct flag value
 345                  */
 346                 Status = (u8)XTTCPS_CLK_CNTRL_PS_DISABLE;
 347         }
 348         else {
 349
 350                 Status = (u8)((ClockReg & (u32)XTTCPS_CLK_CNTRL_PS_VAL_MASK) >>
 351                         (u32)XTTCPS_CLK_CNTRL_PS_VAL_SHIFT);
 352         }
 353         return Status;
 354 }
 355
 356 /*****************************************************************************/
 357 /**
 358 *
 359 * This function calculates the interval value as well as the prescaler value
 360 * for a given frequency.
 361 *
 362 * @param        InstancePtr is a pointer to the XTtcPs instance.
 363 * @param        Freq is the requested output frequency for the device.
 364 * @param        Interval is the interval value for the given frequency,
 365 *               it is the output value for this function.
 366 * @param        Prescaler is the prescaler value for the given frequency,
 367 *               it is the output value for this function.
 368 *
 369 * @return       None.
 370 *
 371 * @note
 372 *  Upon successful calculation for the given frequency, Interval and Prescaler
 373 *  carry the settings for the timer counter; Upon unsuccessful calculation,
 374 *  Interval and Prescaler are set to 0xFF(FF) for their maximum values to
 375 *  signal the caller of failure. Therefore, caller needs to check the return
 376 *  interval or prescaler values for whether the function has succeeded.
 377 *
 378 ****************************************************************************/
 379 void XTtcPs_CalcIntervalFromFreq(XTtcPs *InstancePtr, u32 Freq,
 380         u16 *Interval, u8 *Prescaler)
 381 {
 382         u8 TmpPrescaler;
 383         u32 TempValue;
 384         u32 InputClock;
 385
 386         InputClock = InstancePtr->Config.InputClockHz;
 387         /*
 388          * Find the smallest prescaler that will work for a given frequency. The
 389          * smaller the prescaler, the larger the count and the more accurate the
 390          *  PWM setting.
 391          */
 392         TempValue = InputClock/ Freq;
 393
 394         if (TempValue < 4U) {
 395                 /*
 396                  * The frequency is too high, it is too close to the input
 397                  * clock value. Use maximum values to signal caller.
 398                  */
 399                 *Interval = 0xFFFFU;
 400                 *Prescaler = 0xFFU;
 401                 return;
 402         }
 403
 404         /*
 405          * First, do we need a prescaler or not?
 406          */
 407         if (((u32)65536U) > TempValue) {
 408                 /*
 409                  * We do not need a prescaler, so set the values appropriately
 410                  */
 411                 *Interval = (u16)TempValue;
 412                 *Prescaler = XTTCPS_CLK_CNTRL_PS_DISABLE;
 413                 return;
 414         }
 415
 416
 417         for (TmpPrescaler = 0U; TmpPrescaler < XTTCPS_CLK_CNTRL_PS_DISABLE;
 418              TmpPrescaler++) {
 419                 TempValue =     InputClock/ (Freq * (1U << (TmpPrescaler + 1U)));
 420
 421                 /*
 422                  * The first value less than 2^16 is the best bet
 423                  */
 424                 if (((u32)65536U) > TempValue) {
 425                         /*
 426                          * Set the values appropriately
 427                          */
 428                         *Interval = (u16)TempValue;
 429                         *Prescaler = TmpPrescaler;
 430                         return;
 431                 }
 432         }
 433
 434         /* Can not find interval values that work for the given frequency.
 435          * Return maximum values to signal caller.
 436          */
 437         *Interval = 0XFFFFU;
 438         *Prescaler = 0XFFU;
 439         return;
 440 }
 441 /** @} */