Re: U-boot and linux command line parameters
I have done some experiments with u-boot (version 1.2.0) and with linux kernel (version 2.6.23) and it seems to be that the limitation of 8MB is not anymore the problem. I have built u-boot and linux for ppc405 (virtex-4). I have set the CFG_BOOTMAPSZ to 16 MB: #define CFG_BOOTMAPSZ (8 << 21) /* 16 MB */ and Linux has picked up the command line parameters which were set in u-boot. >/* > * For booting Linux, the board info and command line data > * have to be in the first 8 MB of memory, since this is > * the maximum mapped by the Linux kernel during initialization. > */ > #define CFG_BOOTMAPSZ (8 << 20) /* Initial Memory map for > Linux */ -- View this message in context: http://www.nabble.com/U-boot-and-linux-command-line-parameters-tp23698384p23712750.html Sent from the linuxppc-dev mailing list archive at Nabble.com. ___ Linuxppc-dev mailing list Linuxppc-dev@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-dev
Re: U-boot and linux command line parameters
Dear Mirek23, In message <23703397.p...@talk.nabble.com> you wrote: > > Thank you for your answer. When studying the u-boot source code I have found Will you please STOP posting the same questions on sevral mailing lists, especially without any form of cross-reference? Please read http://www.catb.org/~esr/faqs/smart-questions.html so you understand why you might not receive any further replies. Best regards, Wolfgang Denk -- DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: w...@denx.de How many NASA managers does it take to screw in a lightbulb? "That's a known problem... don't worry about it." ___ Linuxppc-dev mailing list Linuxppc-dev@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-dev
Re: U-boot and linux command line parameters
Thank you for your answer. When studying the u-boot source code I have found that it is indeed register r6 and r7 which pass the location of the command line parameters and the size. The location of the parameters could be changed in u-boot according to the macro: CFG_BOOTMAPSZ There is however the message in all configuration files for u-boot that Linux can only map first initial 8MB so it seems to be not possible to set CFG_BOOTMAPSZ to something higher than 8MB? /* * For booting Linux, the board info and command line data * have to be in the first 8 MB of memory, since this is * the maximum mapped by the Linux kernel during initialization. */ #define CFG_BOOTMAPSZ (8 << 20) /* Initial Memory map for Linux */ Does somebody have an idea how to bypass this limitation in linux 2.6.23 or higher? M. -- View this message in context: http://www.nabble.com/U-boot-and-linux-command-line-parameters-tp23698384p23703397.html Sent from the linuxppc-dev mailing list archive at Nabble.com. ___ Linuxppc-dev mailing list Linuxppc-dev@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-dev
Re: U-boot and linux command line parameters
On Sun, May 24, 2009 at 02:38:52PM -0700, Mirek23 wrote: > > Dear All, > > I use linux kernel 2.6.23 and u-boot 1.2.0 (on ppc405 virtex-4 ) for > some time. All works fine when the kernel together with initramfs is > smaller than 8MB. If it is bigger than the kernel does not boot > properly. > > First of all I would like to know how the address for the linux > command line parameters is "transferred" from u-boot to linux for > ppc405 (virtex4 chip)? (via some registers or is it a fixed address > in the memory ie. 8MB?) Does somebody know what should be changed, > in the kernel, in order to move this limitation from 8MB to let say > 12MB? I would be grateful for any hint. IIRC, U-boot 1.2.0 is a version of u-boot before it became device tree aware. Which means if I'm reading the cuboot.c code correctly, the command line address is passed to the kernel at entry in r6, with the length in r7. With later, device-tree aware u-boot versions, the command line is instead passed as a device tree property. -- David Gibson| I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_ | _way_ _around_! http://www.ozlabs.org/~dgibson ___ Linuxppc-dev mailing list Linuxppc-dev@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-dev
Re: U-boot and linux command line parameters
Have you considered using a kernel and initrd? Hunter Cobbs On May 24, 2009, at 4:38 PM, Mirek23 wrote: Dear All, I use linux kernel 2.6.23 and u-boot 1.2.0 (on ppc405 virtex-4 ) for some time. All works fine when the kernel together with initramfs is smaller than 8MB. If it is bigger than the kernel does not boot properly. First of all I would like to know how the address for the linux command line parameters is "transferred" from u-boot to linux for ppc405 (virtex4 chip)? (via some registers or is it a fixed address in the memory ie. 8MB?) Does somebody know what should be changed, in the kernel, in order to move this limitation from 8MB to let say 12MB? I would be grateful for any hint. Thanks in advance. M. -- View this message in context: http://www.nabble.com/U-boot-and-linux-command-line-parameters-tp23698384p23698384.html Sent from the linuxppc-dev mailing list archive at Nabble.com. ___ Linuxppc-dev mailing list Linuxppc-dev@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-dev ___ Linuxppc-dev mailing list Linuxppc-dev@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-dev
