Hi Igor, What revision of imx27 silicon do you have? If it's a rev2.0 or 2.1, you shoult take a look a the freescale errata in order to set your PLL properly. Regards. 2012/2/14 Igor Trevisan > Hi, > > I'm working on a custom board based on iMX27L. Initially I worked with > Redboot > as Linux bootloader but now, I'm happily working with Barebox (2012.01.0) > having replaced Redboot with it. > > Everithing is fine (thanks to the guys in the list for helping me!) but... > I noticed that my Linux apps run more slowly within my system if it's > started by Barebox > then if it's started by Redbbot. > I think it's a matter of internal clocks settings. > > I see that Redboot, for example, set: > CSR=0x33F38107 > while Barebox does: > writel(0x33F30307 | CSCR_MPLL_RESTART | CSCR_SPLL_RESTART, CSCR) > That brings to CSR=0x33F30307 at the end of the PLLs restart procedure. > > Reading the Manual I can see that the differences between the two settings > mean having an arm_clk that is 2/3 and an AHB_clk that's the half. > > Is there a particular reason for having these "slower configuration"? > > I tried to change the lowlevel_init.S to force 0x33F38107 into CSCR > at startup but, after that change, my board starts, has time to write > somenthing on the > serial console: > > "barebox 2012.01.0-svn11070-dirty1 (Feb 14 2012 - 11:10:39) > > Board: Freescale iÿ" > > and then restarts... continuously. > > Can anybody help me to understand this and to make (if possible) my > system faster? > Thanks in advance, > Igor > > > -- > "Don't find fault, find a remedy." > (Henry Ford) > > _______________________________________________ > barebox mailing list > barebox@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/barebox > -- _______________________________ *Kamel BOUHARA* 62 Bis Rue Carnot 60610 Lacroix Saint-Ouen Tel n°1: +33634677323 n°2: +33617832904