Hi Misha,
On 24 August 2015 at 03:55, Misha Komarovskiy zombah@gmail.com wrote:
Hello Simon, Confirmed, with vdd_arm set 1.1, snow boots fine.
Best Regards, Misha Komarovskiy zombahatgmaildotcom
Please avoid top posting as it leads to a confusing thread.
Would you like to send a patch to update this?
On Mon, Aug 24, 2015 at 12:31 PM, Misha Komarovskiy zombah@gmail.com wrote:
Hello Simon, 2015.07 and 2015.10-rc1 both boot fine. I use this U-Boot as third stage from SD card/USB stick, im not quite sure what right name for this position from reset vector. I will try to increase ret = exynos_set_regulator("vdd_arm", 1000000); to 1100000 and report result.
You say it is a 3rd-stage - does that mean you are booting U-Boot after the existing SPL and U-Boot have already run? That would explain the problem, since the built-in U-Boot sets the CPU speed to maximum.
We don't have support for CPU clock adjustment in mainline yet.
Best Regards, Misha Komarovskiy zombahatgmaildotcom
On Mon, Aug 24, 2015 at 12:21 AM, Simon Glass sjg@chromium.org wrote:
Hi,
On 21 August 2015 at 09:55, Misha Komarovskiy zombah@gmail.com wrote:
Hello, I have failure in attempt to boot Chromebook Snow with 2015.10-rc2 build snow_defconfig, here is error message, it maybe not full as i have some noise on serial console with device:
U-Boot 2015.10-rc2 (Aug 21 2015 - 15:43:43 +0000) for snow GPU: Exynos5250 @ 1.7 GHz Model: Google Snow Board: Google Snow DRAM: 2 GiB ERROR: read error from device: bad39118 register: 0x1e! at drivers/power/pmic/max77686.c:44/max77686_read() initcall sequence bfdaf3bc failed at call 43e0418c (err=-5) ### ERROR ### Please RESET the board ###
Register 1e is the BUCK3 voltage - see max77686.h.
I don't get the same addresses as you but I suppose we are using different toolchains.
But this is probably being called from exynos_power_init().
The ARM voltage is set to 1.0V. I wonder if that is borderline? We could increase it perhaps to 1.1V. - See the exynos_set_regulator() line for vdd_arm.
It was previous 1.3V in 2015.07 - see max77686_init().
Are you starting U-Boot SPL directly from the reset vector?
Regards, Simon
Regards, Simon