66AK2E05: Changing clock frequency

Ashwini Udupa

Intellectual 330 points

Part Number: 66AK2E05
Other Parts Discussed in Thread: CDCM6208V1, CDCM6208

Hi,

We are designing a 66AK2E05 custom board and we are using PLL settings different from the EVM board.

The EVM board has following clock frequencies:

NETCPCLK : 100MHz

DDRCLK:100MHz

CORECLK:100MHz

SGMII0CLK:156.25MHz

Whereas in our custom board, we have NETCPCLK: 125MHz and DDRCLK:125MHz; the CORECLK and SGMII0CLK are the same.

I have tested the initial bring-up on EVM board but wanted to make sure if bring-up will be fine even in our custom board. So, I wanted to change EVM's frequency to our custom board frequencies and test the initial boot-up. We are using UART bootmode initially and then use SPI bootmode.

Can you please tell me how can I change EVM's clock frequency to NETCLK:125MHz and DDRCLK:125MHz? Can it be done through U-boot or BMC?

Can you please advise the method to do this.

Regards,

Ashwini

over 6 years ago

0 Cvetolin Shulev-XID over 6 years ago

TI__Guru 65405 points

Hi Ashwini,

I've forwarded your query to the hardware design experts. Their feedback should be posted here.

BR
Tsvetolin Shulev

0 Tom Johnson 16214 over 6 years ago in reply to Cvetolin Shulev-XID

TI__Mastermind 46460 points

Ashwini,

I believe the table of configuration values is built into the BMC code. It would need to be modified and rebuilt. The CDCM6208V1 device has a program that can be downloaded to change the settings and then to generate the required configuration values that need to be written over the SPI interface.

Tom

0 Ashwini Udupa over 6 years ago in reply to Tom Johnson 16214

Intellectual 330 points

Hi Tom,

After changing the table of config values in BMC, whether the NETCPCLK and DDRCLK will be changed to 125MHz? Or does it need any additional settings in U-boot too to select this frequency?

Ashwini

0 Tom Johnson 16214 over 6 years ago in reply to Ashwini Udupa

TI__Mastermind 46460 points

Ashwini,

Changing the settings in the BMC will adjust the output from the CDCM6208 clock generator. This has no effect on the programming inside the K2E device. You will need to make appropriate changes to the code running on the K2E device to allow it to operate correctly with the new reference clock frequencies.

Tom

0 Ashwini Udupa over 6 years ago in reply to Tom Johnson 16214

Intellectual 330 points

Thanks Tom. Where can we get the program to change the settings of CDCM6208 clock generator through BMC? Can you please provide? Also, please provide the steps to program it.

Ashwini

0 Tom Johnson 16214 over 6 years ago in reply to Ashwini Udupa

TI__Mastermind 46460 points

Ashwini,

The BMC code is on the website of the 3rd party manufacturer that produces the K2E EVMs: https://www.einfochips.com/partnerships-and-alliances/system-partnerships/texas-instruments/k2e-evm/. The BMC code is available at: https://d1l70g7bseoin8.cloudfront.net/wp-content/uploads/texas-instrument/K2EEVM/ks2evm-bmc-post_v1.1.0.6.zip on this page. This is available as-is. You are welcome to modify it but it is sample code that has limited support.

Tom

Processors

Processors forum

66AK2E05: Changing clock frequency