Hi, experts:
Not find any cci-400 settings in current uefi code.
So, Not need to set cci-400 registers in uefi code?
Because ArmVExpress-CTA15-A7 supports big.LITTLE, so:
It should set cci-400 in its code.
Best wishes,
On 28 February 2014 03:14, TigerLiu@via-alliance.com wrote:
Hi, experts:
Not find any cci-400 settings in current uefi code.
So, Not need to set cci-400 registers in uefi code?
Because ArmVExpress-CTA15-A7 supports big.LITTLE, so:
It should set cci-400 in its code.
UEFI boots on a single A7 code on TC2, so it doesn't need CCI-400.
Best wishes,
Linaro-uefi mailing list Linaro-uefi@lists.linaro.org http://lists.linaro.org/mailman/listinfo/linaro-uefi
Hi, Ryan:
UEFI boots on a single A7 code on TC2, so it doesn't need CCI-400.
So, for a big.LITTLE platform, although it included 2 clusters and 4 cores.
But if UEFI used only 1 core as BSP, put other cores into WFI/WFE state, then no need to care CCI-400 settings?
Will OS kernel set CCI-400 registers?
Best wishes,
Hi Tiger,
On Fri, Feb 28, 2014 at 02:54:11PM +0800, TigerLiu@via-alliance.com wrote:
UEFI boots on a single A7 code on TC2, so it doesn't need CCI-400.
So, for a big.LITTLE platform, although it included 2 clusters and 4 cores.
But if UEFI used only 1 core as BSP, put other cores into WFI/WFE state, then no need to care CCI-400 settings?
Will OS kernel set CCI-400 registers?
I think in most real systems this will be done by pre-UEFI firmware, or even external system controllers.
For an example, look at the ARM Trusted Firmware suite[1], which is what is used on the TC2 platform.
[1] https://github.com/ARM-software/arm-trusted-firmware
Regards,
Leif
(And as Harry points out to me, TC2 doesn't use the ARM Trusted Firmware at all. Everything else below is correct though :)
*gets some more coffee*
On Fri, Feb 28, 2014 at 08:31:40AM +0000, Leif Lindholm wrote:
Hi Tiger,
On Fri, Feb 28, 2014 at 02:54:11PM +0800, TigerLiu@via-alliance.com wrote:
UEFI boots on a single A7 code on TC2, so it doesn't need CCI-400.
So, for a big.LITTLE platform, although it included 2 clusters and 4 cores.
But if UEFI used only 1 core as BSP, put other cores into WFI/WFE state, then no need to care CCI-400 settings?
Will OS kernel set CCI-400 registers?
I think in most real systems this will be done by pre-UEFI firmware, or even external system controllers.
For an example, look at the ARM Trusted Firmware suite[1], which is what is used on the TC2 platform.
[1] https://github.com/ARM-software/arm-trusted-firmware
Regards,
Leif
On 28 February 2014 09:47, TigerLiu@via-alliance.com wrote:
Hi, Leif:
(And as Harry points out to me, TC2 doesn't use the ARM Trusted Firmware at all. Everything else below is correct though :)
Well, I didn't want to say... ;-)
So, maybe Vexpress's boot monitor code has initialized cci-400 before jumping to UEFI code.
No, I don't think so. I don't think CCI-400 is initialised until the linux kernel sets it up.
Best wishes,
-
Leif Lindholm -
Ryan Harkin -
TigerLiu＠via-alliance.com