[U-Boot] Getting started with SPL
*HI, *
*OS:* petalinux https://github.com/Xilinx/u-boot-xlnx/tree/master-next
*Board:* Xilinx z702 evaluation boardhttp://www.xilinx.com/products/boards-and-kits/EK-Z7-ZC702-G.htm having ARM Cortex A9 and FPGA on the zc700 SoC
* Background:* I observed that first message on the console comes after 1 second. It is the message from u-boot. Why this was happening? Because I had to use a fsbl (first stage boot loader)http://blog.fakultaet-technik.de/development-with-zynq-part-3-build-boot-files/ for initialization of hardware. I suspected that it is this fsbl that is consuming 1 second initializing useless hardware which I will not use at all. in fact I am not going to use any fpga bitstream also.
So I am trying to boot my Linux image using uboot-SPL methodhttp://www.denx.de/en/pub/Documents/Presentations/EWC2012_Roeder_Zundel_Fastboot.pdf bypassing fsbl.
The main advantage I can get is perhaps fastest possible boot.
I found thishttps://github.com/Xilinx/u-boot-xlnx/blob/master/doc/README.SPL (README.SPL) document that explains how to work with SPL. However I have following question w.r.t to the this passage in the document:
The building of SPL images can be with: define CONFIG_SPL
Because SPL images normally have a different text base, one has to be configured by defining CONFIG_SPL_TEXT_BASE. The linker script has to be defined with CONFIG_SPL_LDSCRIPT.
Questions:
1- In which file I should define #define CONFIG_SPL and CONFIG_SPL_TEXT_BASE?
2-Where is the linker script? Do I need to define CONFIG_SPL_LDSCRIPT in the linker script ? Source code of SPL enabled u-boot for xilinx board I am using is thishttps://github.com/Xilinx/u-boot-xlnx/tree/master-next
This is the first time I am trying to play with SPL so kindly help me proceed.
Thanks and regards,
HB
Hi
On 04/30/2014 11:32 AM, Heshsham Abdul Basit wrote:
*HI, *
*OS:* petalinux https://github.com/Xilinx/u-boot-xlnx/tree/master-next
it is not OS - it is just xilinx u-boot repo. And petalinux is using this repo too.
*Board:* Xilinx z702 evaluation boardhttp://www.xilinx.com/products/boards-and-kits/EK-Z7-ZC702-G.htm having ARM Cortex A9 and FPGA on the zc700 SoC
- Background:* I observed that first message on the console comes after 1
second. It is the message from u-boot. Why this was happening? Because I had to use a fsbl (first stage boot loader)http://blog.fakultaet-technik.de/development-with-zynq-part-3-build-boot-files/ for initialization of hardware. I suspected that it is this fsbl that is consuming 1 second initializing useless hardware which I will not use at all. in fact I am not going to use any fpga bitstream also.
In standard flow there is bootrom -> fsbl -> u-boot. I have never measured where we are spending time in boot.
So I am trying to boot my Linux image using uboot-SPL methodhttp://www.denx.de/en/pub/Documents/Presentations/EWC2012_Roeder_Zundel_Fastboot.pdf bypassing fsbl.
The main advantage I can get is perhaps fastest possible boot.
yes. But also keep in your mind that depends on which boot device you are using. QSPI mode should be the fastest one.
I found thishttps://github.com/Xilinx/u-boot-xlnx/blob/master/doc/README.SPL (README.SPL) document that explains how to work with SPL. However I have following question w.r.t to the this passage in the document:
The building of SPL images can be with: define CONFIG_SPL
Because SPL images normally have a different text base, one has to be configured by defining CONFIG_SPL_TEXT_BASE. The linker script has to be defined with CONFIG_SPL_LDSCRIPT.
Questions:
1- In which file I should define #define CONFIG_SPL and CONFIG_SPL_TEXT_BASE?
Just config file - you can just grep code and you will find out that it is in include/configs/ folder.
2-Where is the linker script? Do I need to define CONFIG_SPL_LDSCRIPT in the linker script ?
If you want to use private linker script then yes. There is also generic one.
Source code of SPL enabled u-boot for xilinx board I am using is thishttps://github.com/Xilinx/u-boot-xlnx/tree/master-next
yes. I have enabled it by default but for correct function you have to copy ps7_init.c/h files from your hardware design to be align with your hw design
Thanks, Michal
HI Michal.
Thanks for your answers. I have few related questions which I will ask separately.
Rgrds,
Heshsham
On 30/04/2014, Michal Simek monstr@monstr.eu wrote:
Hi
On 04/30/2014 11:32 AM, Heshsham Abdul Basit wrote:
*HI, *
*OS:* petalinux https://github.com/Xilinx/u-boot-xlnx/tree/master-next
it is not OS - it is just xilinx u-boot repo. And petalinux is using this repo too.
*Board:* Xilinx z702 evaluation boardhttp://www.xilinx.com/products/boards-and-kits/EK-Z7-ZC702-G.htm having ARM Cortex A9 and FPGA on the zc700 SoC
- Background:* I observed that first message on the console comes after 1
second. It is the message from u-boot. Why this was happening? Because I had to use a fsbl (first stage boot loader)http://blog.fakultaet-technik.de/development-with-zynq-part-3-build-boot-files/ for initialization of hardware. I suspected that it is this fsbl that is consuming 1 second initializing useless hardware which I will not use at all. in fact I am not going to use any fpga bitstream also.
In standard flow there is bootrom -> fsbl -> u-boot. I have never measured where we are spending time in boot.
So I am trying to boot my Linux image using uboot-SPL methodhttp://www.denx.de/en/pub/Documents/Presentations/EWC2012_Roeder_Zundel_Fastboot.pdf bypassing fsbl.
The main advantage I can get is perhaps fastest possible boot.
yes. But also keep in your mind that depends on which boot device you are using. QSPI mode should be the fastest one.
I found thishttps://github.com/Xilinx/u-boot-xlnx/blob/master/doc/README.SPL (README.SPL) document that explains how to work with SPL. However I have following question w.r.t to the this passage in the document:
The building of SPL images can be with: define CONFIG_SPL
Because SPL images normally have a different text base, one has to be configured by defining CONFIG_SPL_TEXT_BASE. The linker script has to be defined with CONFIG_SPL_LDSCRIPT.
Questions:
1- In which file I should define #define CONFIG_SPL and CONFIG_SPL_TEXT_BASE?
Just config file - you can just grep code and you will find out that it is in include/configs/ folder.
2-Where is the linker script? Do I need to define CONFIG_SPL_LDSCRIPT in the linker script ?
If you want to use private linker script then yes. There is also generic one.
Source code of SPL enabled u-boot for xilinx board I am using is thishttps://github.com/Xilinx/u-boot-xlnx/tree/master-next
yes. I have enabled it by default but for correct function you have to copy ps7_init.c/h files from your hardware design to be align with your hw design
Thanks, Michal
-- Michal Simek, Ing. (M.Eng), OpenPGP -> KeyID: FE3D1F91 w: www.monstr.eu p: +42-0-721842854 Maintainer of Linux kernel - Microblaze cpu - http://www.monstr.eu/fdt/ Maintainer of Linux kernel - Xilinx Zynq ARM architecture Microblaze U-BOOT custodian and responsible for u-boot arm zynq platform
participants (2)
-
Heshsham Abdul Basit -
Michal Simek