[SPAM] [PATCH 1/1] mtd: spi-nor: aspeed: set the decoding size to at least 2MB for AST2600

[Potin Lai (賴柏廷)]

Cédric Le Goater 於 2022/3/5 上午 02:00 寫道:
> On 3/4/22 18:29, Cédric Le Goater wrote:
>> Hello Potin,
>>
>> On 3/4/22 18:07, Potin Lai wrote:
>>> In AST2600, the unit of SPI CEx decoding range register is 1MB, and end
>>> address offset is set to the acctual offset - 1MB. If the flash only has
>>> 1MB, the end address will has same value as start address, which will
>>> causing unexpected errors.
>>
>> Yes. That's probably true.
>>
>>> This patch set the decoding size to at least 2MB to avoid decoding errors.
>>>
>>> Tested:
>>> root at bletchley:~# dmesg | grep "aspeed-smc 1e631000.spi: CE0 window"
>>
>> Could you send all the "aspeed-smc" logs please ? I would like to
>> reproduce on QEMU. You can use these machine options :
>>
>>    fmc-model=<string>     - Change the FMC Flash model
>>    spi-model=<string>     - Change the SPI Flash model
>>
>> to change the default flash device models and see how the driver reacts.
>> Add -trace aspeed_smc_flash_set_segment to see how the QEMU model is
>> configured.
>>
Hi Cédric,

I set spi-model with "mx25l8005", which is actual 1MB flash we are using. Please have a look with logs below.


- Original aspeed-smc.c

[    0.562453] aspeed-smc 1e630000.spi: Using 100 MHz SPI frequency
[    0.562792] aspeed-smc 1e630000.spi: mx25l8005 (1024 Kbytes)
aspeed_smc_flash_set_segment CS0 segreg=0x0 [ 0x30000000 - 0x30000000 ]
[    0.563207] aspeed-smc 1e630000.spi: CE0 window [ 0x30000000 - 0x30100000 ] 1MB
[    0.563377] aspeed-smc 1e630000.spi: CE1 window [ 0x30100000 - 0x30100000 ] 0MB (disabled)
[    0.563593] aspeed-smc 1e630000.spi: read control register: 000b0045
[    0.564044] aspeed-smc 1e630000.spi: Calibration area too uniform, using low speed


- Applied with this patch

[    0.589828] aspeed-smc 1e630000.spi: Using 100 MHz SPI frequency
[    0.590186] aspeed-smc 1e630000.spi: mx25l8005 (1024 Kbytes)
[    0.590410] aspeed-smc 1e630000.spi: CE0 window resized to 2MB (AST2600 Decoding)
aspeed_smc_flash_set_segment CS0 segreg=0x100000 [ 0x30000000 - 0x30200000 ]
[    0.590814] aspeed-smc 1e630000.spi: CE0 window [ 0x30000000 - 0x30200000 ] 2MB
[    0.590996] aspeed-smc 1e630000.spi: CE1 window [ 0x30200000 - 0x30200000 ] 0MB (disabled)
[    0.591184] aspeed-smc 1e630000.spi: read control register: 000b0045
[    0.593019] aspeed-smc 1e630000.spi: Calibration area too uniform, using low speed


>>> [   59.328134] aspeed-smc 1e631000.spi: CE0 window resized to 2MB (AST2600 Decoding)
>>> [   59.343001] aspeed-smc 1e631000.spi: CE0 window [ 0x50000000 - 0x50200000 ] 2MB
>>> root at bletchley:~# devmem 0x1e631030
>>> 0x00100000
>>
>> I thought devmem was banned :)
>>
>> We could expose the main FMC/SPI registers under sysfs or debugfs.
>> The segment registers and the timing registers would be nice to
>> have. I can revive some experimental patch I did a few years ago.
>>
>> If you have some time, could you please try the new driver based
>> on spi-mem ?
>>
>> v3 is pushed here :
>>
>>    https://apc01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgithub.com%2Flegoater%2Flinux%2Fcommits%2Fopenbmc-5.15&data=04%7C01%7Cpotin.lai%40quantatw.com%7C8718347359824295b40408d9fe08e189%7C179b032707fc4973ac738de7313561b2%7C1%7C0%7C637820136390590807%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000&sdata=ZdTzgpoSZRgOqifP%2BuBj%2FXWm1dgDmwiHTN%2FaVPibT8o%3D&reserved=0
>>
>> The patch looks correct but we also want to fix the new driver and
>> I have reworked the window setting part. It should be less fragile.
>> aspeed_spi_chip_adjust_window() still needs to handle HW quirks
>> though.
>
I tested with spi-mem v3 patch, it looks same issue appeared. (spi-model=mx25l800)


[    0.541050] spi-nor spi1.0: mx25l8005 (1024 Kbytes)
aspeed_smc_flash_set_segment CS0 segreg=0x0 [ 0x30000000 - 0x30000000 ]
aspeed_smc_flash_set_segment CS1 segreg=0x7f00010 [ 0x30100000 - 0x38000000 ]
[    0.541976] spi-aspeed-smc 1e630000.spi: Calibration area too uniform, using low speed
[    0.542267] spi-aspeed-smc 1e630000.spi: CE0 read buswidth:1 [0x000b0041]

I think the model mx25l1606e you tested is 2MB flash.


Thanks,
Potin
> Using a mx25l1606e on SPI1, here is what we get :
>
> $ qemu-system-arm -M ast2600-evb,spi-model=mx25l1606e ....
>
> [    1.069297] spi-aspeed-smc 1e630000.spi: registered master spi1
> [    1.069863] spi-aspeed-smc 1e630000.spi: CE0 default window [ 0x30000000 - 0x37ffffff ] 128MB
> [    1.070161] spi-aspeed-smc 1e630000.spi: CE0 setup done
> [    1.070359] spi spi1.0: setup mode 0, 8 bits/w, 100000000 Hz max --> 0
> [    1.071245] spi-aspeed-smc 1e630000.spi: CE0 read OP 0x9f mode:1.0.0.1 naddr:0x0 ndummies:0x0 len:0x6
> [    1.071747] spi-nor spi1.0: mx25l1606e (2048 Kbytes)
> aspeed_smc_flash_set_segment CS0 segreg=0x100000 [ 0x30000000 - 0x30200000 ]
> [    1.072253] spi-aspeed-smc 1e630000.spi: CE0 new window [ 0x30000000 - 0x301fffff ] 2MB
> aspeed_smc_flash_set_segment CS1 segreg=0x7f00020 [ 0x30200000 - 0x38000000 ]
> [    1.072833] spi-aspeed-smc 1e630000.spi: CE1 new window [ 0x30200000 - 0x37ffffff ] 126MB
> [    1.073162] spi-aspeed-smc 1e630000.spi: calculate timing compensation - AHB freq: 200 MHz
> [    1.079692] spi-aspeed-smc 1e630000.spi: Trying HCLK/5 [000b0d41] ...
> [    1.143327] spi-aspeed-smc 1e630000.spi:   * [00000000] 0 HCLK delay, DI delay none : PASS
> [    1.143642] spi-aspeed-smc 1e630000.spi: Trying HCLK/4 [000b0641] ...
> [    1.207062] spi-aspeed-smc 1e630000.spi:   * [00000000] 0 HCLK delay, DI delay none : PASS
> [    1.207404] spi-aspeed-smc 1e630000.spi: Trying HCLK/3 [000b0e41] ...
> [    1.273171] spi-aspeed-smc 1e630000.spi:   * [00000000] 0 HCLK delay, DI delay none : PASS
> [    1.273512] spi-aspeed-smc 1e630000.spi: Trying HCLK/2 [000b0741] ...
> [    1.341648] spi-aspeed-smc 1e630000.spi:   * [00000000] 0 HCLK delay, DI delay none : PASS
> [    1.341942] spi-aspeed-smc 1e630000.spi: Found good read timings at HCLK/2
> [    1.342190] spi-aspeed-smc 1e630000.spi: CE0 read buswidth:1 [0x000b0741]
> [    1.363662] spi-aspeed-smc 1e630000.spi: registered child spi1.0
>
> The new spi-mem driver behaves better (on QEMU).
>
> Thanks,
>
> C.