U-Boot expects PMU_MISC0 register bit 7 is set (see init_bandgap()
in arch/arm/mach-imx/mx6/soc.c) during boot. This bit indicates the
bandgap has stabilized.
With this change, the latest upstream U-Boot (v2021.01-rc3) for imx6
sabrelite board (mx6qsabrelite_defconfig), with a slight change made
by switching CONFIG_OF_SEPARATE to CONFIG_OF_EMBED, boots to U-Boot
shell on QEMU with the following command:
$ qemu-system-arm -M sabrelite -smp 4 -m 1G -kernel u-boot \
-display none -serial null -serial stdio
Boot log below:
U-Boot 2021.01-rc3 (Dec 12 2020 - 17:40:02 +0800)
CPU: Freescale i.MX?? rev1.0 at 792 MHz
Reset cause: POR
Model: Freescale i.MX6 Quad SABRE Lite Board
Board: SABRE Lite
I2C: ready
DRAM: 1 GiB
force_idle_bus: sda=0 scl=0 sda.gp=0x5c scl.gp=0x55
force_idle_bus: failed to clear bus, sda=0 scl=0
force_idle_bus: sda=0 scl=0 sda.gp=0x6d scl.gp=0x6c
force_idle_bus: failed to clear bus, sda=0 scl=0
force_idle_bus: sda=0 scl=0 sda.gp=0xcb scl.gp=0x5
force_idle_bus: failed to clear bus, sda=0 scl=0
MMC: FSL_SDHC: 0, FSL_SDHC: 1
Loading Environment from MMC... *** Warning - No block device, using default environment
In: serial
Out: serial
Err: serial
Net: Board Net Initialization Failed
No ethernet found.
starting USB...
Bus usb@2184000: usb dr_mode not found
USB EHCI 1.00
Bus usb@2184200: USB EHCI 1.00
scanning bus usb@2184000 for devices... 1 USB Device(s) found
scanning bus usb@2184200 for devices... 1 USB Device(s) found
scanning usb for storage devices... 0 Storage Device(s) found
scanning usb for ethernet devices... 0 Ethernet Device(s) found
Hit any key to stop autoboot: 0
=>
Signed-off-by: Bin Meng <bin.meng@windriver.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 20210106063504.10841-2-bmeng.cn@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
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