SPI Flash, how to find the System memory addresses?

Question

How to determine the System memory addresses of SPI Flash used in device running eCos operating system? For example, show flash command returns the following info:

 Flash Device Information:

      CFI Compliant: no
        Command Set: Generic SPI Flash
   Device/Bus Width: x16
 Little Word Endian: no
    Fast Bulk Erase: no
    Multibyte Write: 256 bytes max
  Phys base address: 0xbadf1a5
 Uncached Virt addr: 0x1badf1a5
   Cached Virt addr: 0x2badf1a5
   Number of blocks: 129
         Total size: 8388608 bytes, 8 Mbytes
       Current mode: Read Array
        Device Size: 8388608, Write buffer: 256, Busy bit: 

      Size  Device      Device     Region
Block  kB   Address     Offset     Offset   Region Allocation
----- ---- ---------- ----------- --------- -----------------
    0   32 0x1badf1a5           0         0 Bootloader (32768 bytes)
    1   32 0x1bae71a5       32768       ??? {unassigned}
    2   64 0x1baef1a5       65536         0 Permanent NonVol (65536 bytes)
    3   64 0x1baff1a5      131072         0 Image1
    4   64 0x1bb0f1a5      196608     65536 Image1
    5   64 0x1bb1f1a5      262144    131072 Image1
    6   64 0x1bb2f1a5      327680    196608 Image1
    7   64 0x1bb3f1a5      393216    262144 Image1
    ..  .. ........ 
  127   64 0x1c2bf1a5     8257536   4063232 Image2 (4128768 bytes)
  128   64 0x1c2cf1a5     8323072         0 Dynamic NonVol (65536 bytes)

But these addresses seems is not an actual addresses of memory locations. Because when I try readmem command, it always returns errors. For example, there is an example of readmem command:

readmem -s 4 -n 64 0x80001234 -- Reads 64 bytes as 32-bit values.

When I tried readmem -s 4 -n 16384 0x1baef1a5 it always returns error: ERROR - Address(for any addresses from above table). So I assume these addresses is not an actual Flash Memory addresses. I tnink is this because processor’s memory controller maps the flash address space to the system address space. And flash word-size differs from system word-size. How to find the System memory address to read SPI Flash?

Answer 1

I'm not too familiar with eCos, but my guess is that device address is not a memory address but the address of the hardware device used to access the SPI chip by the OS and bootloader, i.e. something similar to the PCI address like B0:D31:F0 (bus 0, device 31, function 0) on the PC. You should try to find where the flash is mapped into memory and read the chunks using the Offset column.