Main clock changed,ethernet doesn't work

winds2001

Intellectual 350 points

Other Parts Discussed in Thread: AM3358

I design my am3358 board using 25Mhz as main clock, however the am335x_evm board uses 24Mhz.

my uboot version is 2013.01-psp06.00.00.00(in sdk6.0), i modify the code in board.c as belows:

#define V_OSCK 25000000 /*default: 24000000*/

now my ethernet can't link to the host PC.

however if i use 24mhz and change the boot switch ,the ethernet can work.

so ,i think ,if i want use 25mhz as main clock,there my be other sites need to be modified in uboot2013.01-psp06.00.00.00(in sdk6.0) to make ethernet to work.could you help me? thanks

over 11 years ago

0 Biser Gatchev-XID over 11 years ago

TI__Guru**** 393215 points

Hi,

The define you modify is correct. I suppose you change SYSBOOT[15:14] to 10b when you use the 25MHz crystal? You can check also these forum threads:

http://e2e.ti.com/support/arm/sitara_arm/f/791/t/302598.aspx

http://e2e.ti.com/support/arm/sitara_arm/f/791/t/366976.aspx

0 winds2001 over 11 years ago in reply to Biser Gatchev-XID

Intellectual 350 points

when i use 25Mhz as main clock, i change sysboot[15:14] to 10b.

now when i ping 192.168.135.221 in the debug terminal ,the debug terminal then say:

cpsw Waiting for phy auto negotiation to complete …………TIMEOUT!

so does it mean that the phy(AR8031) can't link with host PC(Gigabit). i measure the GTX_CLK is 25Mhz, howerver it seems to be 125Mhz when links to Gigabit host PC.

However,if i use uboot-2011.09-psp04.06.00.03(old uboot) and the main clock is also 25mhz, then the ethernet is ok.

so doesn't it mean my hardware seems to be trouble or the uboot doesn't work?

i am confused.

0 Biser Gatchev-XID over 11 years ago in reply to winds2001

TI__Guru**** 393215 points

winds2001 said:
However,if i use uboot-2011.09-psp04.06.00.03(old uboot) and the main clock is also 25mhz, then the ethernet is ok.

You mean it's OK both in 100Mbit and 1Gbit? Then it's surely a SW issue in the new u-boot.

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Main clock changed,ethernet doesn't work