RMII interfere SPI Flash in OMAPL138 EVM

Hi Ran,

     GP6[2] is connected to LAN8710 and Voltage Translator IC whose output[SPI clock and data] is connected to the SPI flash[BUFF_OEn]. BUFF_OEn needs to be low for the SPI flash operation as well as LAN8710 operation . BUFF_OEn is used to enable[BUFF_OEn =0] and disable[BUFF_OEn = 1] the MII MDC clock. During RMII operation, MDC clock to the LAN8710  is disabled by configuring the GP6[2] as output and driving the output high. Since this line also drives the Voltage Translator IC,  output of the IC moves to high impedance state and hence clock as well as data to the SPI clock is disabled..

I have attached the schematics for your reference.

Regards,

N.Sugumar

Hi,

So is it possible to work with both RMII and SPI Flashin the OMAP L138 EVM ?

should I put the mux configuration of G6[2] in remark so that both RMII and SPI Flash would work ?

Regards,

Ran

Hi Ran,

       G6[2] needs to be driven high for the RMII to work. So, both RMII and SPI cannot work together. You can make the hardware change to make them work simultaneously. Remove the connection between BUFF_OEn and 2OE (Active Low) pin of Voltage Translator IC or simply remove the R171 resistor.

Regards,

N.Sugumar

do you have the reference desing how to connect customer board to mac PHY using RMII interface?

Hi,

Just enable the RMII (and disable the MII flags)..

/*
 * Network & Ethernet Configuration
 */

#define CONFIG_DRIVER_TI_EMAC
#ifdef CONFIG_DRIVER_TI_EMAC
#define CONFIG_MII
#undef CONFIG_DRIVER_TI_EMAC_USE_RMII
#define CONFIG_BOOTP_DEFAULT
#define CONFIG_BOOTP_DNS
#define CONFIG_BOOTP_DNS2
#define CONFIG_BOOTP_SEND_HOSTNAME
#define CONFIG_NET_RETRY_COUNT 10
#define CONFIG_NET_MULTI
#define CONFIG_NETCONSOLE

#define CONFIG_DRIVER_TI_EMAC_USE_RMII
#undef CONFIG_MII

#endif /* CONFIG_DRIVER_TI_EMAC */

If you still have problems maybe its better to check that there is no duplicated confiuration of the same pins (pinmux) as the RMII pins:

#ifdef CONFIG_DRIVER_TI_EMAC_USE_RMII
 { pinmux[14], 8, 2 },
 { pinmux[14], 8, 3 },
 { pinmux[14], 8, 4 },
 { pinmux[14], 8, 5 },
 { pinmux[14], 8, 6 },
 { pinmux[14], 8, 7 },
 { pinmux[15], 8, 1 },
#else...

Regards,

Ran

Hi, Ran,

thanks for replying, do you have any schematic attached for the network part?

and I found another way to modify this

use RMII phy: menuconfig menu,
system type->ti davinci implementation->select peripherals connected to expender on UI board->RMII

Regards,

Power Pan

Hi,

I have configured it in the U-boot so far, I guess you are talking about the kernel configuration.

About the schematic, did you try look at the EVM schematics:

http://focus.ti.com/docs/toolsw/folders/print/tmdxoskl138bet.html

Regards,

Ran

Hi,

thanks for the reply. I have a logicPD evm here, but they use MII interface, no RMII interface for reference.

can you tell me how you make it in u-boot? thanks.

Regards,

Pan

Hi Pan,

In one of my previous replies I wrote which flags you should add in the u-boot (da850evm.h for example).
After you done that, you can test your ethernet RMII connection with ping for example (while the console is still the serial).

Regards,

Ran