[U-Boot] CFI Driver Problem: flash not ready

Ross Morley
2008-10-23T02:20:12Z

I ran into this symptom once. In that instance a compiler bug
caused 'volatile' not to be honored when there were two reads
in a single expression, so it read the status only once and
saw no toggle. The workaround was to split the expression to
two statements so each read was in a different statement (the
compiler has since been fixed). Check your generated ASM code.

Ross Morley

Wolfgang Denk wrote:

>Hi,
>
>while tryong to convert the TQM8260 board to using the CFI flash
>driver (instead of a perfectly working legacy flash driver) I ran
>into a strange problem: after an erase operation, the CFI driver
>returns without any error indication, but the flash is not ready yet.
>It takes some more milliseconds before the flash gets ready - by then
>it's indeed erased, but this behaviour makes things like "saveenv" or
>any "erase;cp" command sequences fail with a "Flash not Erased" error
>message.
>
>Symptoms look like this:
>
>=> md 40300000 10 ; era 40300000 +1 ; md 40300000 ; echo ===== ; sleep 1 ; md 40300000
>40300000: 19852003 0000000c f060dc98 ffffffff .. ......`......
>40300010: ffffffff ffffffff ffffffff ffffffff ................
>40300020: ffffffff ffffffff ffffffff ffffffff ................
>40300030: ffffffff ffffffff ffffffff ffffffff ................
>
>. done
>Erased 1 sectors
>40300000: 004c004c 00080008 004c004c 00080008 .L.L.....L.L....
>40300010: 004c004c 00080008 004c004c 00080008 .L.L.....L.L....
>40300020: 004c004c 00080008 004c004c 00080008 .L.L.....L.L....
>40300030: 004c004c 00080008 004c004c 00080008 .L.L.....L.L....
>=====
>40300000: ffffffff ffffffff ffffffff ffffffff ................
>40300010: ffffffff ffffffff ffffffff ffffffff ................
>40300020: ffffffff ffffffff ffffffff ffffffff ................
>40300030: ffffffff ffffffff ffffffff ffffffff ................
>=>
>
>The board uses 4 x 29LV652UE-90 flash chips for a single 32 MiB flash
>bank, 64 bit wide; the old legacy driver showed:
>
> Bank # 1: FUJITSU 29LV640D (64 M, uniform sector)
> Size: 32 MB in 128 Sectors
>
>The CFI driver says:
>
> Bank # 1: CFI conformant FLASH (64 x 16) Size: 32 MB in 128 Sectors
> AMD Standard command set, Manufacturer ID: 0x04, Device ID: 0x22D7
> Erase timeout: 16384 ms, write timeout: 1 ms
>
>CFI debugging shows nothing unusual (at least as far as I can tell):
>
> ...
> FLASH: flash detect cfi
> fwc addr 40000000 cmd f0 f0 8bit x 8 bit
> fwc addr 40000000 cmd ff ff 8bit x 8 bit
> fwc addr 40000055 cmd 98 98 8bit x 8 bit
> is= cmd 51(Q) addr 40000010 is= 80 51
> fwc addr 40000555 cmd 98 98 8bit x 8 bit
> is= cmd 51(Q) addr 40000010 is= 80 51
> fwc addr 40000000 cmd f0 f0f0 16bit x 8 bit
> fwc addr 40000000 cmd ff ffff 16bit x 8 bit
> fwc addr 400000aa cmd 98 9898 16bit x 8 bit
> is= cmd 51(Q) addr 40000020 is= 0000 5151
> fwc addr 40000aaa cmd 98 9898 16bit x 8 bit
> is= cmd 51(Q) addr 40000020 is= 0000 5151
> fwc addr 40000000 cmd f0 00f0 16bit x 16 bit
> fwc addr 40000000 cmd ff 00ff 16bit x 16 bit
> fwc addr 400000aa cmd 98 0098 16bit x 16 bit
> is= cmd 51(Q) addr 40000020 is= 0000 0051
> fwc addr 40000aaa cmd 98 0098 16bit x 16 bit
> is= cmd 51(Q) addr 40000020 is= 0000 0051
> fwc addr 40000000 cmd f0 f0f0f0f0 32bit x 8 bit
> fwc addr 40000000 cmd ff ffffffff 32bit x 8 bit
> fwc addr 40000154 cmd 98 98989898 32bit x 8 bit
> is= cmd 51(Q) addr 40000040 is= 00000000 51515151
> fwc addr 40001554 cmd 98 98989898 32bit x 8 bit
> is= cmd 51(Q) addr 40000040 is= 00000000 51515151
> fwc addr 40000000 cmd f0 00f000f0 32bit x 16 bit
> fwc addr 40000000 cmd ff 00ff00ff 32bit x 16 bit
> fwc addr 40000154 cmd 98 00980098 32bit x 16 bit
> is= cmd 51(Q) addr 40000040 is= 00000000 00510051
> fwc addr 40001554 cmd 98 00980098 32bit x 16 bit
> is= cmd 51(Q) addr 40000040 is= 00000000 00510051
> fwc addr 40000000 cmd f0 000000f0 32bit x 32 bit
> fwc addr 40000000 cmd ff 000000ff 32bit x 32 bit
> fwc addr 40000154 cmd 98 00000098 32bit x 32 bit
> is= cmd 51(Q) addr 40000040 is= 00000000 00000051
> fwc addr 40001554 cmd 98 00000098 32bit x 32 bit
> is= cmd 51(Q) addr 40000040 is= 00000000 00000051
> fwrite addr 40000000 cmd f0 f0f0f0f0f0f0f0f0 64 bit x 8 bit
> fwrite addr 40000000 cmd ff ffffffffffffffff 64 bit x 8 bit
> fwrite addr 400002a8 cmd 98 9898989898989898 64 bit x 8 bit
> is= cmd 51(Q) addr 40000080 is= 0051005100510051 5151515151515151
> fwrite addr 40002aa8 cmd 98 9898989898989898 64 bit x 8 bit
> is= cmd 51(Q) addr 40000080 is= 0051005100510051 5151515151515151
> fwrite addr 40000000 cmd f0 00f000f000f000f0 64 bit x 16 bit
> fwrite addr 40000000 cmd ff 00ff00ff00ff00ff 64 bit x 16 bit
> fwrite addr 400002a8 cmd 98 0098009800980098 64 bit x 16 bit
> is= cmd 51(Q) addr 40000080 is= 0051005100510051 0051005100510051
> is= cmd 52(R) addr 40000088 is= 0052005200520052 0052005200520052
> is= cmd 59(Y) addr 40000090 is= 0059005900590059 0059005900590059
> device interface is 1
> found port 8 chip 2 port 64 bits chip 16 bits
> 00 : 51 52 59 02 00 40 00 00 00 00 00 27 36 00 00 04 QRY.. at .....'6...
> 10 : 00 0a 00 05 00 04 00 17 01 00 00 00 01 7f 00 00 ................
> 20 : 01 00 00 00 00 00 00 00 00 00 00 00 00 ff ff ff ................
> fwrite addr 40000000 cmd f0 00f000f000f000f0 64 bit x 16 bit
> fwrite addr 40002aa8 cmd aa 00aa00aa00aa00aa 64 bit x 16 bit
> fwrite addr 40001550 cmd 55 0055005500550055 64 bit x 16 bit
> fwrite addr 40002aa8 cmd 90 0090009000900090 64 bit x 16 bit
> fwrite addr 40000000 cmd f0 00f000f000f000f0 64 bit x 16 bit
> fwrite addr 400002a8 cmd 98 0098009800980098 64 bit x 16 bit
> manufacturer is 2
> manufacturer id is 0x4
> device id is 0x22d7
> device id2 is 0x0
> cfi version is 0x3131
> size_ratio 4 port 64 bits chip 16 bits
> found 1 erase regions
> erase region 0: 0x0100007f
> erase_region_count = 128 erase_region_size = 65536
> fwrite addr 40000000 cmd f0 00f000f000f000f0 64 bit x 16 bit
> 32 MB
>
>The test from above with debug enabled looks like this:
>
> => md 40300000 10 ; era 40300000 +1 ; md 40300000 ; echo ===== ; sleep 1 ; md 40300000
> 40300000: 19852003 0000000c f060dc98 ffffffff .. ......`......
> 40300010: ffffffff ffffffff ffffffff ffffffff ................
> 40300020: ffffffff ffffffff ffffffff ffffffff ................
> 40300030: ffffffff ffffffff ffffffff ffffffff ................
>
> fwrite addr 40302aa8 cmd aa 00aa00aa00aa00aa 64 bit x 16 bit
> fwrite addr 40301550 cmd 55 0055005500550055 64 bit x 16 bit
> fwrite addr 40302aa8 cmd 80 0080008000800080 64 bit x 16 bit
> fwrite addr 40302aa8 cmd aa 00aa00aa00aa00aa 64 bit x 16 bit
> fwrite addr 40301550 cmd 55 0055005500550055 64 bit x 16 bit
> fwrite addr 40300000 cmd 30 0030003000300030 64 bit x 16 bit
> flash_is_busy: 0
> . done
> Erased 1 sectors
> 40300000: 004c004c 00080008 004c004c 00080008 .L.L.....L.L....
> 40300010: 004c004c 00080008 004c004c 00080008 .L.L.....L.L....
> 40300020: 004c004c 00080008 004c004c 00080008 .L.L.....L.L....
> 40300030: 004c004c 00080008 004c004c 00080008 .L.L.....L.L....
> =====
> 40300000: ffffffff ffffffff ffffffff ffffffff ................
> 40300010: ffffffff ffffffff ffffffff ffffffff ................
> 40300020: ffffffff ffffffff ffffffff ffffffff ................
> 40300030: ffffffff ffffffff ffffffff ffffffff ................
> =>
>
>Why the heck does flash_is_busy() return 0 when the flashobviously is
>still busy?
>
>Thanks in advance.
>
>Best regards,
>
>Wolfgang Denk
>
>
>