Hi Folks,
Please see the following link for further details: https://fedoraproject.org/wiki/Architectures/ARM/Talks/ARMTechTalks
Today's talk is on debugging vexpress (Versatile Express) kernels running under qemu models with gdb. It will simply cover setting up a system for tracing a kernel with gdb and is introductory in nature.
I will host another Fedora ARM technical talk this afternoon. This will be my second, and so I am taking the opportunity to formalize this into a series of technical talks. Each 1-2 weeks I will host a deep dive technical session, on kernel debugging, atomic operations, and covering gnarly issues that I have helped track down (e.g. systemd-logind issue). This is not limited to me - drop me a line if you would like to give a talk, or would like to help organize this series :)
Jon.
On 02/15/2013 02:32 PM, Jon Masters wrote:
Please see the following link for further details: https://fedoraproject.org/wiki/Architectures/ARM/Talks/ARMTechTalks
Today's talk is on debugging vexpress (Versatile Express) kernels running under qemu models with gdb. It will simply cover setting up a system for tracing a kernel with gdb and is introductory in nature.
For today's meeting at 20:00 UTC (15:00 EST, in 20 minutes or so from now), you will want the following files:
* The Versatile Express images downloaded from the wiki instructions: http://fedoraproject.org/wiki/Architectures/ARM/F18/Versatile_Express * A debuginfo kernel for the 3.6.10-8 kernel that shipped with F18: http://armpkgs.fedoraproject.org/packages/kernel/3.6.10/8.fc18/armv7hl/kerne...
Jon.
On 02/15/2013 02:32 PM, Jon Masters wrote:
Please see the following link for further details: https://fedoraproject.org/wiki/Architectures/ARM/Talks/ARMTechTalks
Today's talk is on debugging vexpress (Versatile Express) kernels running under qemu models with gdb. It will simply cover setting up a system for tracing a kernel with gdb and is introductory in nature.
I will host another Fedora ARM technical talk this afternoon. This will be my second, and so I am taking the opportunity to formalize this into a series of technical talks. Each 1-2 weeks I will host a deep dive technical session, on kernel debugging, atomic operations, and covering gnarly issues that I have helped track down (e.g. systemd-logind issue). This is not limited to me - drop me a line if you would like to give a talk, or would like to help organize this series :)
Minutes from today's ARM Tech Talk hosted by me:
HTML: http://meetbot.fedoraproject.org/fedora-arm-talks/2013-02-15/fedora-arm-talk...
Text: http://meetbot.fedoraproject.org/fedora-arm-talks/2013-02-15/fedora-arm-talk...
Raw: http://meetbot.fedoraproject.org/fedora-arm-talks/2013-02-15/fedora-arm-talk...
Tune in next Friday at 20:00 UTC, when John Dulaney will tell us all about installing Fedora onto the Samsung ARM-powered Chromebook!
Jon.
On Fri, Feb 15, 2013 at 04:10:29PM -0500, Jon Masters wrote:
On 02/15/2013 02:32 PM, Jon Masters wrote:
Please see the following link for further details: https://fedoraproject.org/wiki/Architectures/ARM/Talks/ARMTechTalks
Today's talk is on debugging vexpress (Versatile Express) kernels running under qemu models with gdb. It will simply cover setting up a system for tracing a kernel with gdb and is introductory in nature.
I will host another Fedora ARM technical talk this afternoon. This will be my second, and so I am taking the opportunity to formalize this into a series of technical talks. Each 1-2 weeks I will host a deep dive technical session, on kernel debugging, atomic operations, and covering gnarly issues that I have helped track down (e.g. systemd-logind issue). This is not limited to me - drop me a line if you would like to give a talk, or would like to help organize this series :)
Minutes from today's ARM Tech Talk hosted by me:
HTML: http://meetbot.fedoraproject.org/fedora-arm-talks/2013-02-15/fedora-arm-talk...
Text: http://meetbot.fedoraproject.org/fedora-arm-talks/2013-02-15/fedora-arm-talk...
Raw: http://meetbot.fedoraproject.org/fedora-arm-talks/2013-02-15/fedora-arm-talk...
Thanks, this is pretty interesting and helpful :)
Hey everyone,
What would you like my next talk to be on? I will do a hardware debug session soon, but meanwhile I am open to suggestions for the topic after this week - this week John Dulaney is talking about Chromebooks!
Jon.
On Sun, Feb 17, 2013 at 11:55:00PM -0500, Jon Masters wrote:
Hey everyone,
What would you like my next talk to be on? I will do a hardware debug session soon, but meanwhile I am open to suggestions for the topic after this week - this week John Dulaney is talking about Chromebooks!
A talk about device-tree would be cool. An into with how to use/load a device-tree blob and extending into explaining how the plain-text files converted in to blobs cause the kernel to load certain drivers and how these drivers know what pins/memory/options/... to use.
Thanks, Niels
On Fri, Feb 22, 2013 at 3:40 AM, Niels de Vos devos@fedoraproject.orgwrote:
On Sun, Feb 17, 2013 at 11:55:00PM -0500, Jon Masters wrote:
Hey everyone,
What would you like my next talk to be on? I will do a hardware debug session soon, but meanwhile I am open to suggestions for the topic after this week - this week John Dulaney is talking about Chromebooks!
A talk about device-tree would be cool. An into with how to use/load a device-tree blob and extending into explaining how the plain-text files converted in to blobs cause the kernel to load certain drivers and how these drivers know what pins/memory/options/... to use.
This is a great idea. Here are some of my thought to add along with Niels':
* Building the DTB from source ** make some changes if you want
* loaded DTB ** Selecting a safe load addr ** What needs to be doen in u-boot to support loading DTB
* Appended DTB ** Why this is bad ** Why this is good ** example of making an appended DTB and booting.
* FIT images (chromebook) ** mkimage -f ** the dtc utility
* /proc/device-tree ** A guided tour of this new area of /proc ** how it can be used, it's purpose (besides proving the DTB is loaded and working).
It would be great to show the audience some use of Device Tree that help them at a personal level, besides being able to boot their device. For example, I believe the Pandaboard was used as an example early on of how to use DTB to set a persistent mac address. I'm not sure there are any other things the audience might ever want to customize in their DT, but it would be nice to share as many as possible.
** What needs to be done in u-boot to support loading DTB
as far as I can tell (so correct me if I am wrong somewhere).
adding:
#define CONFIG_OF_LIBFDT and possibly (im not sure this might be to use the included dtb files with the uboot source, but they are really kept in the kernel right now.)
#define CONFIG_DEFAULT_DEVICE_TREE I usually add for ext4 support also. :)
#define CONFIG_CMD_EXT4 to u-boot-src/include/configs/boardname.h
On the PogoPlugs You have to muck with the memory addresses since the default environment data is at 0x60000 and the u-boot binary with the dtb is bigger then the 368k so when you do a saveenv it writes over your uboot and crashes :) However the default uboot partition (as defined in uboot itself) starts at 0x0 and ends at 0x100000 (with 20k addresses = 128k) but the environment is 20k addresses, so the max without changing the partition is I think 0x080000. (ie #define CONFIG_ENV_OFFSET 0x80000 /* env starts here */ in the same configs file.)
I have been successful at getting uboot to build and load, and saveenv but I haven't gotten a kernel to boot. It acts like it does when you have the jtag and do a load but forgot to run nand probe 1 to activate it. It pretends to load really fast, but doesn't really work. :)
To build uboot, I have been using the guruplug with f18, rather then setting up the cross-compiler (which i ran into a bug). I'm getting to the uboot prompt so it seems to be working. :)
There are few more things I have to look at though to try and get it to work correctly.
If you aren't worried about trashing the original install on your nand, and have a working jtag or uart serial to load it with, you aren't going to get into too many issues. unless you don't have a working uboot file to reload.. :)
The initial partitions are set in uboot as well as the load addresses.
From: Jon jdisnard@gmail.com To: Fedora ARM secondary architecture list arm@lists.fedoraproject.org Sent: Friday, February 22, 2013 12:06 PM Subject: Re: [fedora-arm] Announcing: Fedora ARM Technical Talks
On Fri, Feb 22, 2013 at 3:40 AM, Niels de Vos devos@fedoraproject.org wrote:
On Sun, Feb 17, 2013 at 11:55:00PM -0500, Jon Masters wrote:
Hey everyone,
What would you like my next talk to be on? I will do a hardware debug session soon, but meanwhile I am open to suggestions for the topic after this week - this week John Dulaney is talking about Chromebooks!
A talk about device-tree would be cool. An into with how to use/load a device-tree blob and extending into explaining how the plain-text files converted in to blobs cause the kernel to load certain drivers and how these drivers know what pins/memory/options/... to use.
This is a great idea. Here are some of my thought to add along with Niels':
- Building the DTB from source
** make some changes if you want
- loaded DTB
** Selecting a safe load addr ** What needs to be doen in u-boot to support loading DTB
- Appended DTB
** Why this is bad ** Why this is good ** example of making an appended DTB and booting.
- FIT images (chromebook)
** mkimage -f ** the dtc utility
- /proc/device-tree
** A guided tour of this new area of /proc ** how it can be used, it's purpose (besides proving the DTB is loaded and working).
It would be great to show the audience some use of Device Tree that help them at a personal level, besides being able to boot their device. For example, I believe the Pandaboard was used as an example early on of how to use DTB to set a persistent mac address. I'm not sure there are any other things the audience might ever want to customize in their DT, but it would be nice to share as many as possible.
--
-Jon Disnard irc: masta fas: parasense _______________________________________________ arm mailing list arm@lists.fedoraproject.org https://admin.fedoraproject.org/mailman/listinfo/arm
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