[U-Boot] Booting i.MX6UL via SPL?
Hi All,
I've been trying to boot a i.MX6UL based device I have here using SPL. It doesn't seem to want to work for me.
I see there's a number of i.MX6UL ports in U-Boot already, some use a custom DCD to configure the board, others seem to provide both options (DCD and SPL). Interestingly the Freescale i.MX 6UltraLite Evaluation Kit port (via mx6ul_14x14_evk_defconfig) appears to be using the SPL mechanism exclusively.
Can someone confirm that the above device boots using this config from SD card?
I seem to be able to boot from SD card using a custom DCD (which copies U-Boot into RAM), I'm also able to get the SPL to boot via USB (which copies the SPL to OCRAM). However when I try to boot the SPL from SD card it doesn't boot. If I boot the SPL via USB, insert an SD card and reset the device, it seems to boot from the SPL previously loaded from USB (as in it's still in the OCRAM) but carries on like it's booted from the SD card (looking on the SD card rather than USB for the main U-Boot image). The reason I think it's doing this is that if I rebuild U-Boot and flash a copy with an updated build time to the SD card, when I perform a reset I still see the old build time in the U-Boot banner. It looks to me like for some reason it's unable to copy the SPL to OCRAM, but carries on thinking it has.
Anyone got any pointers?
Thanks in advance,
Martyn
Hello Martyn,
Am 07.11.2018 um 21:46 schrieb Martyn Welch:
Hi All,
I've been trying to boot a i.MX6UL based device I have here using SPL. It doesn't seem to want to work for me.
I see there's a number of i.MX6UL ports in U-Boot already, some use a custom DCD to configure the board, others seem to provide both options (DCD and SPL). Interestingly the Freescale i.MX 6UltraLite Evaluation Kit port (via mx6ul_14x14_evk_defconfig) appears to be using the SPL mechanism exclusively.
Can someone confirm that the above device boots using this config from SD card?
I seem to be able to boot from SD card using a custom DCD (which copies U-Boot into RAM), I'm also able to get the SPL to boot via USB (which copies the SPL to OCRAM). However when I try to boot the SPL from SD card it doesn't boot. If I boot the SPL via USB, insert an SD card and reset the device, it seems to boot from the SPL previously loaded from USB (as in it's still in the OCRAM) but carries on like it's booted from the SD card (looking on the SD card rather than USB for the main U-Boot image). The reason I think it's doing this is that if I rebuild U-Boot and flash a copy with an updated build time to the SD card, when I perform a reset I still see the old build time in the U-Boot banner. It looks to me like for some reason it's unable to copy the SPL to OCRAM, but carries on thinking it has.
Anyone got any pointers?
Hard to say...
I have running U-Boot wit SPL on a imx6ull based board, booting from SPI NOR.
If you have a setup with DCD, also SPL should work, but be sure to setup correct RAM config. But you say, SPL works when loading through USB
I added for imx6ull:
#undef CONFIG_SPL_STACK #define CONFIG_SPL_STACK 0x00918000
You use CONFIG_SYS_EXTRA_OPTIONS="IMX_CONFIG=arch/arm/mach-imx/spl_sd.cfg"
?
bye, Heiko
Hi Martyn,
On 07/11/18 21:46, Martyn Welch wrote:
Hi All,
I've been trying to boot a i.MX6UL based device I have here using SPL. It doesn't seem to want to work for me.
I see there's a number of i.MX6UL ports in U-Boot already, some use a custom DCD to configure the board, others seem to provide both options (DCD and SPL). Interestingly the Freescale i.MX 6UltraLite Evaluation Kit port (via mx6ul_14x14_evk_defconfig) appears to be using the SPL mechanism exclusively.
Can someone confirm that the above device boots using this config from SD card?
I seem to be able to boot from SD card using a custom DCD (which copies U-Boot into RAM), I'm also able to get the SPL to boot via USB (which copies the SPL to OCRAM). However when I try to boot the SPL from SD card it doesn't boot. If I boot the SPL via USB, insert an SD card and reset the device, it seems to boot from the SPL previously loaded from USB (as in it's still in the OCRAM) but carries on like it's booted from the SD card (looking on the SD card rather than USB for the main U-Boot image). The reason I think it's doing this is that if I rebuild U-Boot and flash a copy with an updated build time to the SD card, when I perform a reset I still see the old build time in the U-Boot banner. It looks to me like for some reason it's unable to copy the SPL to OCRAM, but carries on thinking it has.
Anyone got any pointers?
I confirm that SPL works for a MX6UL, but I had this issue, too. It could depend on the Hardware Revision of your processor.
There is a bug in revision 1.2 of the processor that makes the first part of the OCRAM not available and SPL cannot be copied. This bug affects just some production charges, and NXP solved this later without changing the revision of the processor. That means there are some boards where everything is fine, some other boards with just a newer processor that do not boot. I do not know if this is your use case, but it makes sense to give a try.
I had just moved CONFIG_SPL_TEXT_BASE to a later offset:
define CONFIG_SPL_TEXT_BASE 0x00909000
However, there is no chance to know at runtime if a board is affected by this issue because the revision does not change, and I do not think it is a good idea to force all MX6UL to restrict their OCRAM due to a buggy and time constrained production by the manufacturer.
I hope this helps, Stefano
On Thu, 2018-11-08 at 11:25 +0100, Stefano Babic wrote:
Hi Martyn,
On 07/11/18 21:46, Martyn Welch wrote:
Hi All,
I've been trying to boot a i.MX6UL based device I have here using SPL. It doesn't seem to want to work for me.
I see there's a number of i.MX6UL ports in U-Boot already, some use a custom DCD to configure the board, others seem to provide both options (DCD and SPL). Interestingly the Freescale i.MX 6UltraLite Evaluation Kit port (via mx6ul_14x14_evk_defconfig) appears to be using the SPL mechanism exclusively.
Can someone confirm that the above device boots using this config from SD card?
I seem to be able to boot from SD card using a custom DCD (which copies U-Boot into RAM), I'm also able to get the SPL to boot via USB (which copies the SPL to OCRAM). However when I try to boot the SPL from SD card it doesn't boot. If I boot the SPL via USB, insert an SD card and reset the device, it seems to boot from the SPL previously loaded from USB (as in it's still in the OCRAM) but carries on like it's booted from the SD card (looking on the SD card rather than USB for the main U-Boot image). The reason I think it's doing this is that if I rebuild U-Boot and flash a copy with an updated build time to the SD card, when I perform a reset I still see the old build time in the U-Boot banner. It looks to me like for some reason it's unable to copy the SPL to OCRAM, but carries on thinking it has.
Anyone got any pointers?
I confirm that SPL works for a MX6UL, but I had this issue, too. It could depend on the Hardware Revision of your processor.
There is a bug in revision 1.2 of the processor that makes the first part of the OCRAM not available and SPL cannot be copied. This bug affects just some production charges, and NXP solved this later without changing the revision of the processor. That means there are some boards where everything is fine, some other boards with just a newer processor that do not boot. I do not know if this is your use case, but it makes sense to give a try.
I had just moved CONFIG_SPL_TEXT_BASE to a later offset:
define CONFIG_SPL_TEXT_BASE 0x00909000
Thanks Stefano, this was exactly the issue that I was hitting!
Martyn
However, there is no chance to know at runtime if a board is affected by this issue because the revision does not change, and I do not think it is a good idea to force all MX6UL to restrict their OCRAM due to a buggy and time constrained production by the manufacturer.
I hope this helps, Stefano
participants (3)
-
Heiko Schocher -
Martyn Welch -
Stefano Babic