?? nandfs.c
字號:
{ // // There are 1024 blocks in this device. // sNAND.usNumBlocks = 1024; // // There are 32 pages per block in this device. // sNAND.ucPagesPerBlock = 32; // // Fill in the function pointers for accessing this FLASH // device. // sNAND.pfnRead = NANDRead_512_3; sNAND.pfnWrite = NANDWrite_512_3; sNAND.pfnErase = NANDErase_32_3; // // We've interpreted the device ID. // break; } // // The device capacity is 32MB. // case 0x75: { // // There are 2048 blocks in this device. // sNAND.usNumBlocks = 2048; // // There are 32 pages per block in this device. // sNAND.ucPagesPerBlock = 32; // // Fill in the function pointers for accessing this FLASH // device. // sNAND.pfnRead = NANDRead_512_3; sNAND.pfnWrite = NANDWrite_512_3; sNAND.pfnErase = NANDErase_32_3; // // We've interpreted the device ID. // break; } // // The device capacity is 64MB. // case 0x76: { // // There are 4096 blocks in this device. // sNAND.usNumBlocks = 4096; // // There are 32 pages pre block in this device. // sNAND.ucPagesPerBlock = 32; // // Fill in the function pointers for accessing this FLASH // device. // sNAND.pfnRead = NANDRead_512_4; sNAND.pfnWrite = NANDWrite_512_4; sNAND.pfnErase = NANDErase_32_4; // // We've interpreted the device ID. // break; } // // The device capacity is 128MB. // case 0x79: { // // There are 8192 blocks in this device. // sNAND.usNumBlocks = 8192; // // There are 32 pages per block in this device. // sNAND.ucPagesPerBlock = 32; // // Fill in the function pointers for accessing this FLASH // device. // sNAND.pfnRead = NANDRead_512_4; sNAND.pfnWrite = NANDWrite_512_4; sNAND.pfnErase = NANDErase_32_4; // // We've interpreted the device ID. // break; } // // Either the FLASH device could not be found or it has an unknown // device ID. // default: { // // Return a failure. // sNAND.usNumBlocks = 0; sNAND.ucPagesPerBlock = 0; pulGPIO[HwPortABCD >> 2] |= HwPortABCD_NAND1_CS; return(0); } } // // See if the on-board NAND FLASH is formatted. // if(!CheckNAND(pucScratch, pucWriteBuffer)) { // // The on-board NAND FLASH is not formatted, so format it now. // FormatNAND(pucScratch, pucWriteBuffer); } // // Read the length of the file. // ulDeviceID = sNAND.ucPagesPerBlock - 1; NextPage(&ulDeviceID); (sNAND.pfnRead)(HwNANDAddress, ulDeviceID, pucScratch, pucWriteBuffer); sNAND.ulFileLength = pucScratch[0] | (pucScratch[1] << 8) | (pucScratch[2] << 16) | (pucScratch[3] << 24); // // De-select the on-board NAND FLASH. // pulGPIO[HwPortABCD >> 2] |= HwPortABCD_NAND1_CS; // // Success. // return(1); } // // Make sure that we were able to successfully initialize the on-board NAND // FLASH. Return a failure if we could not. // if(sNAND.usNumBlocks == 0) { return(0); } // // Determine what to do based on the specified IOCTL. // switch(ulIoctl) { // // Return the media unique ID. // case IOCTL_FS_GETMEDIAID: { // // We do not support a media unique ID, so return failure. // return(0); } // // Open the specified file. We do not support multiple files, so we // also don't care what the file name is...any open will work for the // single file in the file system. // case IOCTL_FS_OPEN: { tNANDFile *pFile; // // We do not support writing to a file that we do not create. // if((ulParam2 & FS_OPEN_CREATE) && !(ulParam2 & FS_OPEN_WRITE)) { return(0); } // // Get a pointer to the file structure. // pFile = (tNANDFile *)ulInstance; // // Get the first page used to store file data. // pFile->ulPage = sNAND.ucPagesPerBlock - 1; NextPage(&(pFile->ulPage)); // // Select the on-board NAND FLASH. // pulGPIO[HwPortABCD >> 2] &= ~HwPortABCD_NAND1_CS; // // Are we reading or writing? // if(ulParam2 & FS_OPEN_READ) { // // If the file length is zero, then there is no file in the // on-board NAND FLASH, so return a failure. // if(sNAND.ulFileLength == 0) { pulGPIO[HwPortABCD >> 2] |= HwPortABCD_NAND1_CS; return(0); } } else { // // Erase the first block of the on-board NAND FLASH. // NANDWaitTilNotBusy(HwNANDAddress); (sNAND.pfnErase)(HwNANDAddress, pFile->ulPage / sNAND.ucPagesPerBlock); // // Skip to the next page of the on-board NAND FLASH. // NextPage(&(pFile->ulPage)); // // The initial file length is zero. // sNAND.ulFileLength = 0; } // // Set the file position to the beginning. // pFile->ulFilePos = 0; // // De-select the on-board NAND FLASH. // pulGPIO[HwPortABCD >> 2] |= HwPortABCD_NAND1_CS; // // Success. // return(1); } // // Create the specified file. // case IOCTL_FS_CREATE: { tNANDFile *pFile; // // Get a pointer to the file structure. // pFile = (tNANDFile *)ulInstance; // // Get the first page used to store file data. // pFile->ulPage = sNAND.ucPagesPerBlock - 1; NextPage(&(pFile->ulPage)); // // Select the on-board NAND FLASH. // pulGPIO[HwPortABCD >> 2] &= ~HwPortABCD_NAND1_CS; // // Erase the first block of the on-board NAND FLASH. // NANDWaitTilNotBusy(HwNANDAddress); (sNAND.pfnErase)(HwNANDAddress, pFile->ulPage / sNAND.ucPagesPerBlock); // // Skip to the next page of the on-board NAND FLASH. // NextPage(&(pFile->ulPage)); // // The initial file length is zero. // sNAND.ulFileLength = 0; // // Set the file position to the beginning. // pFile->ulFilePos = 0; // // De-select the on-board NAND FLASH. // pulGPIO[HwPortABCD >> 2] |= HwPortABCD_NAND1_CS; // // Success. // return(1); } // // Read data from the currently opened file. // case IOCTL_FS_READ: { tNANDFile *pFile; unsigned long ulCount; // // Make sure that the number of bytes requested is a multiple of // 512. // if(ulParam2 & 511) { return(0); } // // Get a pointer to the file structure. // pFile = (tNANDFile *)ulInstance; // // Select the on-board NAND FLASH. // pulGPIO[HwPortABCD >> 2] &= ~HwPortABCD_NAND1_CS; // // Read pages from the on-board NAND FLASH. // ulCount = 0; while(ulParam2) { // // Stop reading if we've reached the end of the file. // if(pFile->ulFilePos >= sNAND.ulFileLength) { break; } // // Read the next page from the on-board NAND FLASH. // (sNAND.pfnRead)(HwNANDAddress, NextPage(&(pFile->ulPage)), (unsigned char *)ulParam1, pucScratch); // // Increment the read buffer pointer. // ulParam1 += 512; // // Decrement the count of bytes to read. // ulParam2 -= 512; // // Increment the file position. // pFile->ulFilePos += 512; // // Increment the count of bytes read. // ulCount += 512; } // // De-select the on-board NAND FLASH. // pulGPIO[HwPortABCD >> 2] |= HwPortABCD_NAND1_CS; // // Success. // return(ulCount); } // // Read data from the currently opened file, performing a byte-swap. // case IOCTL_FS_READ_BS: { tNANDFile *pFile; unsigned long ulCount, ulIdx; // // Make sure that the number of bytes requested is a multiple of // 512. // if(ulParam2 & 511) { return(0); } // // Get a pointer to the file structure. // pFile = (tNANDFile *)ulInstance; // // Select the on-board NAND FLASH. // pulGPIO[HwPortABCD >> 2] &= ~HwPortABCD_NAND1_CS; // // Read pages from the on-board NAND FLASH. // ulCount = 0; while(ulParam2) { // // Stop reading if we've reached the end of the file. // if(pFile->ulFilePos >= sNAND.ulFileLength) { break; } // // Read the next page from the on-board NAND FLASH, byte // swapping the data as we read it. // (sNAND.pfnRead)(HwNANDAddress, NextPage(&(pFile->ulPage)), (unsigned char *)ulParam1, pucScratch); // // Swap the bytes in the page. // for(ulIdx = 0; ulIdx < 512; ulIdx += 4) { unsigned long ulTemp; ulTemp = ((unsigned long *)ulParam1)[ulIdx >> 2]; ulTemp = ((ulTemp << 24) & 0xff000000) | ((ulTemp << 8) & 0x00ff0000) | ((ulTemp >> 8) & 0x0000ff00) | ((ulTemp >> 24) & 0x000000ff); ((unsigned long *)ulParam1)[ulIdx >> 2] = ulTemp; } // // Increment the read buffer pointer. // ulParam1 += 512; // // Decrement the count of bytes to read. // ulParam2 -= 512; // // Increment the file position. // pFile->ulFilePos += 512; // // Increment the count of bytes read.?? 快捷鍵說明
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