[U-Boot] How to reduce SDcard speed in u-boot

[Michael Trimarchi]

Hi

On Wed, Apr 8, 2015 at 3:22 PM, Marco Cavallini
<cavallini.koan at gmail.com> wrote:
> 2015-04-03 16:26 GMT+02:00 Michael Trimarchi <michael at amarulasolutions.com>:
>> Hi
>>
>> Increase the divisor of the clock
>>
>> MXC_CCM_CSCDR1_USDHC[X]_PODF_MASK
>> MXC_CCM_CSCDR1_USDHC[X]_PODF_OFFSET
>>
>> I'm not sure because I have not a board and no time before Easter
>> to open documentation ;)
>>
>> Michael
>>
>
>
>
> Hi Michael,
> the register CCM_CSCDR1 did the trick, thank you.
> Unfortunately on the buggy hardware I have the same problem (printed below).
>
> =========
>
> On the working board
>
>> md.l 020c4024 1
>
>> clocks
> PLL_SYS         792 MHz
> PLL_BUS         528 MHz
> PLL_OTG         480 MHz
> PLL_NET          50 MHz
>
> IPG           66000 kHz
> UART          80000 kHz
> AHB          132000 kHz
> AXI          198000 kHz
> DDR          396000 kHz
> USDHC1       198000 kHz
> USDHC2       198000 kHz
> USDHC3       198000 kHz
> USDHC4       198000 kHz
> EMI SLOW      99000 kHz
> IPG PERCLK    66000 kHz
>
>> run loadk
> reading uImage
> 5157968 bytes read in 454 ms (10.8 MiB/s)
>
> Increased divisor below:
>
>> mw.l 020c4024 00790b00
>
>> clocks
> PLL_SYS         792 MHz
> PLL_BUS         528 MHz
> PLL_OTG         480 MHz
> PLL_NET          50 MHz
>
> IPG           66000 kHz
> UART          80000 kHz
> AHB          132000 kHz
> AXI          198000 kHz
> DDR          396000 kHz
> USDHC1       198000 kHz
> USDHC2       198000 kHz
> USDHC3        49500 kHz  <-------

Try 25Mhz

Michael

> USDHC4       198000 kHz
> EMI SLOW      99000 kHz
> IPG PERCLK    66000 kHz
>
>> run loadk
> reading uImage
> 5157968 bytes read in 882 ms (5.6 MiB/s) <--- slower upload into memory
>
> =========
>
> On the buggy board : ERROR
>
>> fatload mmc 0:1 0x12000000 uImage
> reading uImage
> Error reading cluster
> ** Unable to read file uImage **
>> fatload mmc 0:1 0x12000000 uImage
> ** Can't read partition table on 0:0 **
> ** Invalid partition 1 **
>> fatload mmc 0:1 0x12000000 uImage
> ** Can't read partition table on 0:0 **
> ** Invalid partition 1 **
>
> Ciao
> --
> Marco
> _______________________________________________
> U-Boot mailing list
> U-Boot at lists.denx.de
> http://lists.denx.de/mailman/listinfo/u-boot



-- 
| Michael Nazzareno Trimarchi                     Amarula Solutions BV |
| COO  -  Founder                                      Cruquiuskade 47 |
| +31(0)851119172                                 Amsterdam 1018 AM NL |
|                  [`as] http://www.amarulasolutions.com               |