Eric Heim wrote: > Anyone know of a patch for the MPC8349 clocking scheme. All my time > tests are indicating that the clock is running at half speed though I > see no indication in the /proc/cpuinfo. I run a sleep(5) and it takes > ten seconds but gettimeofday( ) and the time base register indicate that > 5 seconds passed. >
Hi Tim, Can you let us know the kernel and the u-boot version you are using (and the origin, eg. Freescale or Denx or ...). The issue could be in either U-Boot or Linux. 0n my MDS board with the latest U-Boot and Denx Linux kernel, bdinfo indication 528MHz CPU, 264MHz bus frequency, then Linux shows these same numbers in /proc/cpuinfo. date; sleep 10; date run on the x86 development machine at the same time as the MDS board (well, as fast as I could move my mouse), showed a 10s delay on both, and both finished at the same time. So, I think its fixed. grep for csb_clk in the latest U-boot source shows it up in cpu/mpc83xx/speed.c, lbiu_clk is also in there. (lbiu_clk is the local-bus interface unit clock). I'm not sure which clock is used for the timer time-base, so find out the clock source of the timer the kernel is using, and then check the clock settings in your U-Boot versus the latest source (which you can obtain using the git tool from Denx's repository). grep in the arch/ppc folder of the Linux source (Denx git version) didn't show anything for csb_clk or lbiu_clk, so either their names are different there, or the U-Boot source is the location of the problem setting. I believe Kumar posted a csb_clk (or lbiu_clk) patch that fixed a setting error ... but I can't recall if it was a U-Boot patch or a kernel patch. I looked in the CHANGELOG for U-Boot and I didn't see a comment related to the clock settings (searching based on Kumar, MPC8349, or MPC83xx). Perhaps someone reading the list has a better recollection than I :) Cheers Dave
