Question about reading NORflash data using ioremap16

Source: Internet
Author: User
For more information about how to use ioremap16 to read NORflash data-Linux general technology-Linux programming and kernel, see the following. Let me explain the situation first:
I am now using AT91RM9200 to read a mounted 28F128J3D norflash with a size of 16 M and a physical address starting from 0x1000 0000

Now we can test the reading flash data in the driver: the code is as follows:
# Define BASE_FLASH (unsigned long) 0x10640000)
Static int _ init eth_init (void)
Volatile unsigned int data;
Void * flash_add;
Int I;
Request_mem_region (BASE_FLASH, 0x18, "flash ");
Flash_add = ioremap (BASE_FLASH, 0x18 );
For (I = 0; I <12; I ++ ){
Iowrite16 (WORD_PROGRAM_COMMAND, flash_add );
Iowrite16 (0x1234, flash_add + 0x2 * I );
Iowrite16 (READ_ARRAY_COMMAND, flash_add );
Data = ioread16 (flash_add + 0x2 * I );
Printk ("data = % d \ n", data );
Printk ("init module \ n ");
Return 0;

The following problems occur:
1. If flash writing can only write two bytes, that is, the iowrite16 () function is executed only once;
2. If ioread16 () is executed after iowrite16 (), you can write all the pairs;
3. If the data read by ioread16 () is incorrect, all data is 127;
Bytes ----------------------------------------------------------------------------------------------------------
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