Joakim Tjernlund schrieb: >>I wrote, >> >> >>>I have an I2C RTC connected to my MPC855T to substitute the internal one. >>> >>>I noticed that between >>> >>> Verifying Checksum ... OK >>> Uncompressing Kernel Image ... OK >>> >>>and the next lines printed while booting "nothing" happens for THREE >>>seconds. >>> >>>I reckon that is has something to do with not having an external 32kHz >>>clock on the MPC. But I can't find the place in the sources! >> >>I migth have found it: >> >>Is it ok and enough to set >> >> ppc_md.set_rtc_time = NULL; >> ppc_md.get_rtc_time = NULL; >> >>in platform_init()? And then later - when I2C is initialized - set it >>to the appropriate I2C RTC functions? > > > Yes, that's it. If your kernel ever hangs after printing out > "calibrating delay loop ...", try adding a set_tb(0,0) somewhere in > m8xx_setup.c, > to see if it fixes it.
Thanks Jocke! > You may also want to add an "I2C reset sequence" in your firmware/kernel > if your I2C clock gets stuck and don't respond(can happen if reset/power down > while > reading the RTC). Look in u-boot for details. Yeah. I know. I should put into PPCBoot/U-Boot. But in the docs it says it's only for SOFT_I2C aka bitbang! So a) can I toggle the pins using GPIO and still use HARD_I2C? or b) can I use SOFT_I2C in PPCBoot and CPM I2C (8xx-algo) under linux? Steven ** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/
