Hello, On 10/18/20 1:17 AM, Robert Carnecky (Neopsis) wrote: > On Sat, Oct 17, 2020 at 11:29 PM Ahmad Fatoum <a.fatoum@xxxxxxxxxxxxxx> wrote: >> >> Hi, >> >> On 10/17/20 1:31 PM, Robert Carnecky (Neopsis) wrote: >>> Finally, I managed to boot into barebox menu using UART1 (/dev/ttyS0) >>> as the console. The solution was to remove all UART related overlays >>> from config.txt and only activate UART1. >>> >>> enable_uart=1 >>> >>> Anyway, another problem occurred. When booting via barebox the CPU >>> serial number is wrong. Obviously, barebox somehow manipulates the >>> internal structures and >>> >>> cat /proc/cpuinfo >>> >>> returns always >>> >>> Hardware : BCM2835 >>> Revision : 0000 >>> Serial : 0000000000000000 >>> Model : Raspberry Pi Compute Module 3 IO board V3.0 >>> >>> When I boot the same image directly without barebox boot loader, the >>> info is OK. I found some discussions about U-Boot and wrong serial >>> number here >>> >>> https://www.raspberrypi.org/forums/viewtopic.php?t=183474#p1162778 >>> >>> maybe that's barebox related too. Anyway, that is a definitive no go >>> with barebox for us because parts of our software are expecting the >>> unique serial number. >> >> I believe you can boot Linux with /vc.dtb and you'll get the same >> device tree passed to Linux as if you booted without passing through >> barebox. > > Yes, but then I lose my Linux console! A summary, in all cases Barebox device > tree in arch/arm/dts/bcm2837-rpi-cm3.dts was updated following your hint, e.g. > > / { > chosen { > stdout-path = "&uart1"; > }; > }; > > &uart1 { > pinctrl-names = "default"; > pinctrl-0 = <&uart1_gpio14>; > status = "okay"; > }; > > &uart0 { > pinctrl-names = "default"; > pinctrl-0 = <&uart0_gpio32>; > status = "okay"; > }; > > 1. Booting kernel direct, works as expected (console on uart1), > expected behavior > > kernel=zImage > enable_uart=1 > dtoverlay=uart0,txd0_pin=32,rxd0_pin=33,pin_func=7 > dtoverlay=uart1,txd1_pin=14,rxd1_pin=15 > > 2. With Barebox loader. The same config.txt as in case 1), > - no Barebox console > - kernel boots with the console on uart1 > > kernel=barebox-raspberry-pi-cm3.img > enable_uart=1 > dtoverlay=uart0,txd0_pin=32,rxd0_pin=33,pin_func=7 > dtoverlay=uart1,txd1_pin=14,rxd1_pin=15 > > 3. With Barebox loader, no uart overlays in config.txt. > - Barebox console on uart1 ok, > - kernel console on uart1 > - almost done), but ... no cpuinfo > > kernel=barebox-raspberry-pi-cm3.img > enable_uart=1 > > 4. With Barebox loader, no uart overlays in config.txt, Linux boots with vc.dtb. > - Barebox console on uart1 ok > - no Linux console, Linux boots with cpuinfo ok > > kernel=barebox-raspberry-pi-cm3.img > enable_uart=1 > > I did not found any combination when I get the Barebox console and > Linux console on uart1 > and with cpuinfo ok. If the serial number is not needed, case 3) should be ok. What happens if you combine 2. and 4. ? So you have enable_uart=1, the uart overlays _and_ Linux boots with vc.dtb? > > Robert > >> >>> >>> Robert >>> >>> >>> On Fri, Oct 9, 2020 at 4:18 PM Ahmad Fatoum <a.fatoum@xxxxxxxxxxxxxx> wrote: >>>> >>>> Hello Robert, >>>> >>>> On 10/9/20 2:30 PM, Robert Carnecky (Neopsis) wrote: >>>>>> Try adding to arch/arm/dts/bcm2837-rpi-cm3.dts: >>>>>> >>>>>> &uart1 { >>>>>> pinctrl-names = "default"; >>>>>> pinctrl-0 = <&uart1_gpio14>; >>>>>> status = "okay"; >>>>>> }; >>>>> >>>>> I extended arch/arm/dts/bcm2837-rpi-cm3.dts as advised + >>>>> additionally I set UART0 to pins 32/33. >>>>> >>>>> &uart0 { >>>>> pinctrl-names = "default"; >>>>> pinctrl-0 = <&uart0_gpio32>; >>>>> status = "okay"; >>>>> }; >>>>> >>>>> I still cannot see Barebox console on boot, however, the Barebox loader >>>>> starts in 3 seconds my kernel and I get the Linux console output on >>>>> UART1/ttyS0. >>>> >>>> Strange that this made the kernel boot now. Maybe somewhere an unclocked >>>> peripheral was being accessed before? >>>> >>>>> Now my Linux boots as expected, unfortunately without >>>>> visible Barebox console. I tried all Barebox console setting >>>>> (NONE/ALL/FIRST), same result, no Barebox console output on UART0 >>>>> or UART1. >>>> >>>> Huh, you did listen at the UART0 _before_ the RS-485 transceiver? >>>> UART0 should work, at least it apparently did when the CM3 support >>>> was added. >>>> >>>>>> If that doesn't help, use CONSOLE_ACTIVATE_ALL and listen >>>>>> on UART0 before the RS-485 transceiver and paste the >>>>>> dmesg and devinfo input you get. >>>>> >>>>> # dmesg | grep tty >>>>> [ 0.000000] Kernel command line: console=ttyS0,115200 >>>>> coherent_pool=1M snd_bcm2835.enable_compat_alsa=0 >>>>> snd_bcm2835.enable_hdmi=1 snd_bcm2835.enable_headphones=1 >>>>> 8250.nr_uarts=1 bcm2708_fb.fbwidth=656 >>>>> bcm2708_fb.fbheight=416 bcm2708_fb.fbswap=1 >>>>> smsc95xx.macaddr=B8:27:EB:C5:7D:E3 vc_mem.mem_base=0x3ec00000 >>>>> vc_mem.mem_size=0x40000000 root=/dev/mmcblk0p2 console=ttyS0,115200 >>>>> rootfstype=ext4 elevator=deadline rootwait >>>>> [ 1.289058] printk: console [ttyS0] disabled >>>>> [ 1.289175] 3f215040.serial: ttyS0 at MMIO 0x0 (irq = 53, base_baud >>>>> = 50000000) is a 16550 >>>>> [ 1.945483] printk: console [ttyS0] enabled >>>>> [ 2.432604] 3f201000.serial: ttyAMA0 at MMIO 0x3f201000 (irq = 81, >>>>> base_baud = 0) is a PL011 rev2 >>>>> >>>>> # stty -F /dev/ttyAMA0 115200 >>>>> # cat /etc/inittab > /dev/ttyAMA0 <- OK >>>> >>>> I meant dmesg under barebox, if UART1 fails to output, but UART0 can be >>>> read before the transceiver. >>>> >>>> On 10/6/20 1:32 AM, Robert Carnecky (Neopsis) wrote: >>>>> I played a bit more with the config.txt settings and when I activated the flag >>>>> >>>>> uart_2ndstage=1 >>>>> >>>>> I got the barebox console! Here a snippet from the 2stage while >>>>> logging the UART lading. >>>> >>>> Oh. That would indicate that there is some sort of initialization missing. >>>> uart_2ndstage=1 initializes the UART for VideoCore use apparently and from >>>> there on, it works. >>>> >>>>> What I do not understand: how the loaded /mfs/sd/bcm2710-rpi-cm3.dtb >>>>> and the overlays >>>>> cooperate with the Barebox device tree? Does it mean we have two sets >>>>> of device tree >>>>> files? >>>> >>>> Yes. The VideoCore device tree is available in barebox as /vc.dtb, >>>> see e390c8799d91 ("ARM: rpi: save fdt that was passed from VideoCore") >>>> >>>> >>>> Hope this helps, >>>> Ahmad >>>> >>>> -- >>>> Pengutronix e.K. | | >>>> Steuerwalder Str. 21 | http://www.pengutronix.de/ | >>>> 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | >>>> Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | >>> >> >> -- >> Pengutronix e.K. | | >> Steuerwalder Str. 21 | http://www.pengutronix.de/ | >> 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | >> Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | > -- Pengutronix e.K. | | Steuerwalder Str. 21 | http://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | _______________________________________________ barebox mailing list barebox@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/barebox
