Projects/AVRISP-MKII/Lib/XPROG/TINYNVM.c

   1 /*
   2              LUFA Library
   3      Copyright (C) Dean Camera, 2010.
   4
   5   dean [at] fourwalledcubicle [dot] com
   6       www.fourwalledcubicle.com
   7 */
   8
   9 /*
  10   Copyright 2010  Dean Camera (dean [at] fourwalledcubicle [dot] com)
  11
  12   Permission to use, copy, modify, distribute, and sell this
  13   software and its documentation for any purpose is hereby granted
  14   without fee, provided that the above copyright notice appear in
  15   all copies and that both that the copyright notice and this
  16   permission notice and warranty disclaimer appear in supporting
  17   documentation, and that the name of the author not be used in
  18   advertising or publicity pertaining to distribution of the
  19   software without specific, written prior permission.
  20
  21   The author disclaim all warranties with regard to this
  22   software, including all implied warranties of merchantability
  23   and fitness.  In no event shall the author be liable for any
  24   special, indirect or consequential damages or any damages
  25   whatsoever resulting from loss of use, data or profits, whether
  26   in an action of contract, negligence or other tortious action,
  27   arising out of or in connection with the use or performance of
  28   this software.
  29 */
  30
  31 /** \file
  32  *
  33  *  Target-related functions for the TINY target's NVM module.
  34  */
  35
  36 #define  INCLUDE_FROM_TINYNVM_C
  37 #include "TINYNVM.h"
  38
  39 #if defined(ENABLE_XPROG_PROTOCOL) || defined(__DOXYGEN__)
  40
  41 /** Sends the given pointer address to the target's TPI pointer register */
  42 static void TINYNVM_SendPointerAddress(const uint16_t AbsoluteAddress)
  43 {
  44         /* Send the given 16-bit address to the target, LSB first */
  45         XPROGTarget_SendByte(TPI_CMD_SSTPR | 0);
  46         XPROGTarget_SendByte(((uint8_t*)&AbsoluteAddress)[0]);
  47         XPROGTarget_SendByte(TPI_CMD_SSTPR | 1);
  48         XPROGTarget_SendByte(((uint8_t*)&AbsoluteAddress)[1]);
  49 }
  50
  51 /** Sends a SIN command to the target with the specified I/O address, ready for the data byte to be written.
  52  *
  53  *  \param[in] Address  6-bit I/O address to write to in the target's I/O memory space
  54  */
  55 static void TINYNVM_SendReadNVMRegister(const uint8_t Address)
  56 {
  57         /* The TPI command for reading from the I/O space uses strange addressing, where the I/O address's upper
  58          * two bits of the 6-bit address are shifted left once */
  59         XPROGTarget_SendByte(TPI_CMD_SIN | ((Address & 0x30) << 1) | (Address & 0x0F));
  60 }
  61
  62 /** Sends a SOUT command to the target with the specified I/O address, ready for the data byte to be read.
  63  *
  64  *  \param[in] Address  6-bit I/O address to read from in the target's I/O memory space
  65  */
  66 static void TINYNVM_SendWriteNVMRegister(const uint8_t Address)
  67 {
  68         /* The TPI command for reading from the I/O space uses strange addressing, where the I/O address's upper
  69          * two bits of the 6-bit address are shifted left once */
  70         XPROGTarget_SendByte(TPI_CMD_SOUT | ((Address & 0x30) << 1) | (Address & 0x0F));
  71 }
  72
  73 /** Busy-waits while the NVM controller is busy performing a NVM operation, such as a FLASH page read.
  74  *
  75  *  \return Boolean true if the NVM controller became ready within the timeout period, false otherwise
  76  */
  77 bool TINYNVM_WaitWhileNVMBusBusy(void)
  78 {
  79         /* Poll the STATUS register to check to see if NVM access has been enabled */
  80         for (;;)
  81         {
  82                 /* Send the SLDCS command to read the TPI STATUS register to see the NVM bus is active */
  83                 XPROGTarget_SendByte(TPI_CMD_SLDCS | TPI_STATUS_REG);
  84
  85                 uint8_t StatusRegister = XPROGTarget_ReceiveByte();
  86
  87                 /* We might have timed out waiting for the status register read response, check here */
  88                 if (!(TimeoutTicksRemaining))
  89                   return false;
  90
  91                 /* Check the status register read response to see if the NVM bus is enabled */
  92                 if (StatusRegister & TPI_STATUS_NVM)
  93                   return true;
  94         }
  95 }
  96
  97 /** Waits while the target's NVM controller is busy performing an operation, exiting if the
  98  *  timeout period expires.
  99  *
 100  *  \return Boolean true if the NVM controller became ready within the timeout period, false otherwise
 101  */
 102 bool TINYNVM_WaitWhileNVMControllerBusy(void)
 103 {
 104         /* Poll the STATUS register to check to see if NVM access has been enabled */
 105         for (;;)
 106         {
 107                 /* Send the SIN command to read the TPI STATUS register to see the NVM bus is busy */
 108                 TINYNVM_SendReadNVMRegister(XPROG_Param_NVMCSRRegAddr);
 109
 110                 uint8_t StatusRegister = XPROGTarget_ReceiveByte();
 111
 112                 /* We might have timed out waiting for the status register read response, check here */
 113                 if (!(TimeoutTicksRemaining))
 114                   return false;
 115
 116                 /* Check to see if the BUSY flag is still set */
 117                 if (!(StatusRegister & (1 << 7)))
 118                   return true;
 119         }
 120 }
 121
 122 /** Reads memory from the target's memory spaces.
 123  *
 124  *  \param[in]  ReadAddress  Start address to read from within the target's address space
 125  *  \param[out] ReadBuffer   Buffer to store read data into
 126  *  \param[in]  ReadSize     Length of the data to read from the device
 127  *
 128  *  \return Boolean true if the command sequence complete successfully
 129  */
 130 bool TINYNVM_ReadMemory(const uint16_t ReadAddress,
 131                         uint8_t* ReadBuffer,
 132                         uint16_t ReadSize)
 133 {
 134         /* Wait until the NVM controller is no longer busy */
 135         if (!(TINYNVM_WaitWhileNVMControllerBusy()))
 136           return false;
 137
 138         /* Set the NVM control register to the NO OP command for memory reading */
 139         TINYNVM_SendWriteNVMRegister(XPROG_Param_NVMCMDRegAddr);
 140         XPROGTarget_SendByte(TINY_NVM_CMD_NOOP);
 141
 142         /* Send the address of the location to read from */
 143         TINYNVM_SendPointerAddress(ReadAddress);
 144
 145         while (ReadSize-- && TimeoutTicksRemaining)
 146         {
 147                 /* Read the byte of data from the target */
 148                 XPROGTarget_SendByte(TPI_CMD_SLD | TPI_POINTER_INDIRECT_PI);
 149                 *(ReadBuffer++) = XPROGTarget_ReceiveByte();
 150         }
 151
 152         return (TimeoutTicksRemaining != 0);
 153 }
 154
 155 /** Writes word addressed memory to the target's memory spaces.
 156  *
 157  *  \param[in] WriteAddress  Start address to write to within the target's address space
 158  *  \param[in] WriteBuffer   Buffer to source data from
 159  *  \param[in] WriteLength   Total number of bytes to write to the device (must be an integer multiple of 2)
 160  *
 161  *  \return Boolean true if the command sequence complete successfully
 162  */
 163 bool TINYNVM_WriteMemory(const uint16_t WriteAddress,
 164                          uint8_t* WriteBuffer,
 165                          uint16_t WriteLength)
 166 {
 167         /* Wait until the NVM controller is no longer busy */
 168         if (!(TINYNVM_WaitWhileNVMControllerBusy()))
 169           return false;
 170
 171         /* Must have an integer number of words to write - if extra byte, word-align via a dummy high byte */
 172         if (WriteLength & 0x01)
 173           WriteBuffer[WriteLength++] = 0xFF;
 174
 175         /* Set the NVM control register to the WORD WRITE command for memory reading */
 176         TINYNVM_SendWriteNVMRegister(XPROG_Param_NVMCMDRegAddr);
 177         XPROGTarget_SendByte(TINY_NVM_CMD_WORDWRITE);
 178
 179         /* Send the address of the location to write to */
 180         TINYNVM_SendPointerAddress(WriteAddress);
 181
 182         while (WriteLength)
 183         {
 184                 /* Wait until the NVM controller is no longer busy */
 185                 if (!(TINYNVM_WaitWhileNVMControllerBusy()))
 186                   return false;
 187
 188                 /* Write the low byte of data to the target */
 189                 XPROGTarget_SendByte(TPI_CMD_SST | TPI_POINTER_INDIRECT_PI);
 190                 XPROGTarget_SendByte(*(WriteBuffer++));
 191
 192                 /* Write the high byte of data to the target */
 193                 XPROGTarget_SendByte(TPI_CMD_SST | TPI_POINTER_INDIRECT_PI);
 194                 XPROGTarget_SendByte(*(WriteBuffer++));
 195
 196                 /* Need to decrement the write length twice, since we read out a whole word */
 197                 WriteLength -= 2;
 198         }
 199
 200         return true;
 201 }
 202
 203 /** Erases the target's memory space.
 204  *
 205  *  \param[in] EraseCommand  NVM erase command to send to the device
 206  *  \param[in] Address       Address inside the memory space to erase
 207  *
 208  *  \return Boolean true if the command sequence complete successfully
 209  */
 210 bool TINYNVM_EraseMemory(const uint8_t EraseCommand,
 211                          const uint16_t Address)
 212 {
 213         /* Wait until the NVM controller is no longer busy */
 214         if (!(TINYNVM_WaitWhileNVMControllerBusy()))
 215           return false;
 216
 217         /* Set the NVM control register to the target memory erase command */
 218         TINYNVM_SendWriteNVMRegister(XPROG_Param_NVMCMDRegAddr);
 219         XPROGTarget_SendByte(EraseCommand);
 220
 221         /* Write to a high byte location within the target address space to start the erase process */
 222         TINYNVM_SendPointerAddress(Address | 0x0001);
 223         XPROGTarget_SendByte(TPI_CMD_SST | TPI_POINTER_INDIRECT);
 224         XPROGTarget_SendByte(0x00);
 225
 226         /* Wait until the NVM controller is no longer busy */
 227         if (!(TINYNVM_WaitWhileNVMControllerBusy()))
 228           return false;
 229
 230         return true;
 231 }
 232
 233 #endif