From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Seiderer Date: Mon, 9 May 2016 22:51:50 +0200 Subject: [Buildroot] [PATCH v2] raspberrypi3: fix serial console (load pi3-miniuart-bt overlay) In-Reply-To: References: <1462220744-6368-1-git-send-email-ps.report@gmx.net> <871t5jr7e6.fsf@dell.be.48ers.dk> <20160503210200.12d685a7@gmx.net> Message-ID: <20160509225150.7f4f40e7@gmx.net> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: buildroot@busybox.net Hello Martin, On Mon, 9 May 2016 14:19:48 +0100, Martin Bark wrote: > Peter, > > On 3 May 2016 at 20:02, Peter Seiderer wrote: > > Hello Martin, > > > > On Tue, 3 May 2016 11:23:50 +0100, Martin Bark wrote: > > > >> All, > >> > >> On 3 May 2016 at 07:18, Peter Korsgaard wrote: > >> >>>>>> "Oscar" == Oscar Gomez Fuente writes: > >> > > >> > > Hi Peter Seiderer, > >> > > What's the difference between enabling pi3-miniuart-bt instead of > >> > > pi3-disable-bt? > >> > > >> > > With pi3-disable-bt enables it works fine the serial console on (14 [TxD] & > >> > > 15 [RxD] pins). > >> > > >> > From the names I would guess it is the difference between completely > >> > disabling access to the bluetooth module and providing access to it > >> > though the secondary (mini) uart. > >> > > >> > The miniuart has some limitations, but I guess basic bluetooth stuff > >> > should work with it. > >> > >> I've got a bit lost in the rpi3 serial console issues but as i > >> understand the current situation all you need to do is set > >> enable_uart=1 in config.txt. See > >> https://github.com/raspberrypi/firmware/issues/553#issuecomment-199486644. > >> I've not tested this. > >> > >> I think you also need to change cmdline.txt to use console=serial0 as > >> the pi3-miniuart-bt will replace it with the correct serial device > >> (ttyAMA0 or ttyS0) depending if it's enabled or not. See the comments > >> in https://github.com/raspberrypi/linux/blob/rpi-4.1.y/arch/arm/boot/dts/overlays/pi3-miniuart-bt-overlay.dts. > >> > > > > This works too, not sure whats the better solution, explicit via device tree overlay > > or some firmware magic.... > > > > - pi3-miniuart-bt 'dmesg | grep tty': > > [ 0.000000] Kernel command line: 8250.nr_uarts=1 dma.dmachans=0x7f35 bcm2708_fb.fbwidth=1920 bcm2708_fb.fbheight=1200 bcm2709.boardrev=0xa02082 bcm2709.serial=0xa60340 smsc95xx.macaddr=B8:27:EB:A6:03:40 bcm2708_fb.fbswap=1 bcm2709.uart_clock=48000000 vc_mem.mem_base=0x3dc00000 vc_mem.mem_size=0x3f000000 root=/dev/mmcblk0p2 rootwait console=tty1 console=ttyAMA0,115200 > > [ 0.001320] console [tty1] enabled > > [ 0.318181] 3f215040.uart: ttyS0 at MMIO 0x3f215040 (irq = 59, base_baud = 50000000) is a 16550 > > [ 2.008162] 3f201000.uart: ttyAMA0 at MMIO 0x3f201000 (irq = 87, base_baud = 0) is a PL011 rev2 > > [ 3.296233] console [ttyAMA0] enabled > > > > - enable-uart=1, serial0 dmesg | grep tty': > > [ 0.000000] Kernel command line: 8250.nr_uarts=1 dma.dmachans=0x7f35 bcm2708_fb.fbwidth=1920 bcm2708_fb.fbheight=1200 bcm2709.boardrev=0xa02082 bcm2709.serial=0xa60340 smsc95xx.macaddr=B8:27:EB:A6:03:40 bcm2708_fb.fbswap=1 bcm2709.uart_clock=48000000 vc_mem.mem_base=0x3dc00000 vc_mem.mem_size=0x3f000000 root=/dev/mmcblk0p2 rootwait console=tty1 console=ttyS0,115200 > > [ 0.001318] console [tty1] enabled > > [ 0.318270] console [ttyS0] disabled > > [ 0.318389] 3f215040.uart: ttyS0 at MMIO 0x3f215040 (irq = 59, base_baud = 31250000) is a 16550 > > [ 1.042714] console [ttyS0] enabled > > [ 3.020277] 3f201000.uart: ttyAMA0 at MMIO 0x3f201000 (irq = 87, base_baud = 0) is a PL011 rev2 > > > > I wonder if the solution is to just document the situation in > board/raspberrypi/readme.txt. The documentation could just detail the > available choices for Bluetooth and serial console on the rpi3 and how > to configure each manually. A summary of the available choices is: > > 1) Default setup - Serial console does not work, Bluetooth works > 2) Add enable-uart=1 - Serial console works but the core frequency is > fixed. Serial console max baud rate is less than the rpi2. Bluetooth > works. > 3) Use pi3-miniuart-bt - Serial console works the same as the rpi2 but > Bluetooth runs slow. > 4) Use pi3-disable-bt - Serial console works the same as the rpi2 but > Bluetooth is disabled. > > What do you think? Agreed, with bias to 3) as the default (or one of the other solutions with serial console enabled)... Regards, Peter > > Thanks > > Martin > > > Regards, > > Peter > > > > > >> Thanks > >> > >> Martin > >> > >> > > >> > -- > >> > Venlig hilsen, > >> > Peter Korsgaard > >> > _______________________________________________ > >> > buildroot mailing list > >> > buildroot at busybox.net > >> > http://lists.busybox.net/mailman/listinfo/buildroot > >