From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thierry Bultel Date: Fri, 21 Mar 2014 19:47:48 +0100 Subject: [U-Boot] Running mx6qsabrelite at 1Gz with Freescale kernel rel_imx_3.0.35_4.1.0 In-Reply-To: <53283D62.7060200@denx.de> References: <1395142110.53282ddeee751@imp.free.fr> <53283D62.7060200@denx.de> Message-ID: <532C8954.3010409@free.fr> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Le 18/03/2014 13:34, Stefano Babic a ?crit : > Hi Thierry, > > > On 18/03/2014 12:28, tbultel at free.fr wrote: >> >> Hi, >> >> I am working on a board (AMOS820 from Via) based on the mx6qsabrelite. >> >> The BSP provided by the manufacturer is quite old. >> I managed to port it from Freescale uboot-imx rel_imx_3.0.35_4.1.0 to u-boot >> mainline, and basically the latest issue I have is the cpu frequency. >> >> The kernel I use is the rel_imx_3.0.35_4.1.0 as well (same tag name) >> >> With the old u-boot, it runs at 1Ghz because the BSP explicitly has a call to >> >> clk_config(CONFIG_REF_CLK_FREQ, 1000, CPU_CLK); >> >> With the new u-boot, it runs at default freq which is 800Mhz (at least, what I >> guess from the Bogomips because no other log says it) > It is can taken as reference, but checking the BogoMIPS is not the right > way to proof it. You should take a look at the CCM registers when Linux > is running ( CCM_ANALOG_PLL_ARM). > >> I have attempted to pass "arm_freq=1000" to the boot args but that does not >> change anything. > Well, this is a kernel issue, and related to an ancient version. > >> My concern is that clk_config does not seem to be available anymore, there is >> get_mcu_main_clk but no set routine. > It was never available in mainline. > >> I wonder if it is intentional, I could write a set routine but I wonder if it >> could be accepted as a patch. > Why not ? All patches are discussed here and if it makes sense to merge > it, it will be merged. Hi Stefano, many thanks for your advice, It is now running at 1Ghz. I still have a couple of issues that prevent me to submit a patch as is: 1) The kernel (old, I know) I am using does not like that PCIe to have been formerly probed by u-boot. It hangs at probing if so. Thus I have to patch my kernel, or add an environment variable to not initialize PCIe when set, in order to keep compatible with old kernels. For now, in order to boot, I have temporary disabled PCIe support in U-boot. 2) The splashscreen (loaded at 10000000) disappears when loading the kernel Would you have any idea or hints about it ? Best Regards Thierry > Best regards, > Stefano Babic >