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/*--------------------------------------------------------------------

 * TITLE: Plasma Flash

 * AUTHOR: Steve Rhoads (rhoadss@yahoo.com)

 * DATE CREATED: 12/17/05

 * FILENAME: plasma.h

 * PROJECT: Plasma CPU core

 * COPYRIGHT: Software placed into the public domain by the author.

 *    Software 'as is' without warranty.  Author liable for nothing.

 * DESCRIPTION:

 *    Plasma flash controller

 *    Only the lower 16-bits of each 32-bit word are connected --

 *    this changes the address mapping to the flash.

 *    ByteOffset and bytes must be a multiple of two.

 *--------------------------------------------------------------------*/

#include "plasma.h"

#include "rtos.h"

static OS_Mutex_t *mutexFlash;

void FlashLock(void)

{

   if(mutexFlash == NULL)

      mutexFlash = OS_MutexCreate("flash");

   OS_MutexPend(mutexFlash);

}

void FlashUnlock(void)

{

   OS_MutexPost(mutexFlash);

}

void FlashRead(uint16 *dst, uint32 byteOffset, int bytes)

{

   volatile uint32 *ptr=(uint32*)(FLASH_BASE + (byteOffset << 1));

   FlashLock();

   *ptr = 0xff;                   //read mode

   while(bytes > 0)

   {

      *dst++ = (uint16)*ptr++;

      bytes -= 2;

   }

   FlashUnlock();

}

void FlashWrite(uint16 *src, uint32 byteOffset, int bytes)

{

   volatile uint32 *ptr=(uint32*)(FLASH_BASE + (byteOffset << 1));

   FlashLock();

   while(bytes > 0)

   {

      *ptr = 0x40;                //write mode

      *ptr++ = *src++;            //write data

      while((*ptr & 0x80) == 0)   //check status

         ;

      bytes -= 2;

   }

   FlashUnlock();

}

void FlashErase(uint32 byteOffset)

{

   volatile uint32 *ptr=(uint32*)(FLASH_BASE + (byteOffset << 1));

   FlashLock();

   *ptr = 0x20;                   //erase block

   *ptr = 0xd0;                   //confirm

   while((*ptr & 0x80) == 0)      //check status

      ;

   FlashUnlock();

}