Linux/66AK2G02: Controlling registers with device tree or Kernel API ?

Naoki Kawada

Guru 19890 points

Part Number: 66AK2G02

Tool/software: Linux

Hi,

My customer wants to configure BOOTCFG_ETHERNET_CLKCTL register by using device tree or Kernel API; They just wants to force RMII_MII_CLKSEL bitfield to 0 after Linux kernel booted. Now they are accessing this register by using mmap in the app. Also, they wanted to do the same thing, say, map TIMIx and TIMOx pins to the specific timer, for example, TIMI1 and TIMO1 pins to Timer4's TINPL and TOUTL signal. In the current implementation, they are also using mmap and control the register directly in their app. Could you comment ?

Best Regards,
Naoki Kawada

over 8 years ago

0 Cvetolin Shulev-XID over 8 years ago

TI__Guru 65405 points

Hi Naoki-San,

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

BR
Tsvetolin Shulev

0 Rex Chang over 8 years ago in reply to Cvetolin Shulev-XID

TI__Guru 50170 points

Hi, Naoki,

Why does it need to be in device tree? Device tree is usually used for generic and configurable entity. If they are fixed values, they don't need to be in device tree. Besides, the configuration should be done in u-boot. Specially the configuration for BOOTCFG, it should not be in the kernel. In U-boot, it can be either through memset or environment variable to set the values.

Rex

Processors

Processors forum

Linux/66AK2G02: Controlling registers with device tree or Kernel API ?