Re: [PATCH v3 6/6] tty/serial: atmel: changed the driver to work under at91-usart mfd

From: Radu Pirea
Date: Fri May 25 2018 - 10:07:06 EST




On 05/25/2018 04:35 PM, Richard Genoud wrote:
On 25/05/2018 14:17, Radu Pirea wrote:


On 05/15/2018 04:14 PM, Richard Genoud wrote:
On 15/05/2018 14:47, Radu Pirea wrote:
On Mon, 2018-05-14 at 12:57 +0200, Richard Genoud wrote:
After your patch, the DMA is not selected anymore:
atmel_usart_serial atmel_usart_serial.0.auto: TX channel not
available, switch to pio
instead of:
atmel_usart fffff200.serial: using dma1chan2 for tx DMA transfers

Fixed.
And the kernel doesn't log anymore on the serial console, despite the
loglevel=8
(after reverting this series, the kernel logs reappears on the serial
console)

Which serial are you using as console?
fffff200.serial (sam9g35-cm)
( stdout-path = "serial0:115200n8"; in the DTS )

With this series applied, all the kernel log goes on the screen.
Without, it goes on the serial debug.

I tested again with archlinux arm and poky-linux4sam release as distros
and kernel log goes on the serial debug. Can you give me more details
like cmdline?
I used kernel 4.17-rc6
at91_dt_defconfig
at91sam9g35ek.dtb

Kernel command line: root=/dev/mtdblock1 rw rootfstype=ubifs ubi.mtd=1 root=ubi0:rootfs
I reproduced your issue.
If in cmdline console is not set like this "console=ttyS0,115200", the console goes to the lcd.
( the one from the DTS )

Detailed instructions:

git checkout v4.17-rc6
ARCH=arm CROSS_COMPILE=path_to_my_Xchain/arm-linux- LOADADDR=0x20008000 make -j 12 at91_dt_defconfig
ARCH=arm CROSS_COMPILE=path_to_my_Xchain/arm-linux- LOADADDR=0x20008000 make -j 12 uImage at91sam9g35ek.dtb
cp arch/arm/boot/uImage arch/arm/boot/dts/at91sam9g35ek.dtb /tftpboot/

From uboot:
tftpboot 0x20007FC0 uImage
tftpboot 0x26400000 at91sam9g35ek.dtb
bootm 0x20007FC0 - 0x26400000

[ I see the logs on the serial debug ]

git am \[PATCH\ v3\ [1-6]*

ARCH=arm CROSS_COMPILE=path_to_my_Xchain/arm-linux- LOADADDR=0x20008000 make -j 12 uImage at91sam9g35ek.dtb
cp arch/arm/boot/uImage arch/arm/boot/dts/at91sam9g35ek.dtb /tftpboot/

From uboot:
tftpboot 0x20007FC0 uImage
tftpboot 0x26400000 at91sam9g35ek.dtb
bootm 0x20007FC0 - 0x26400000

[ I don't see the logs on the serial debug anymore ]


(tests done on sam9g35)

I will consider the rest of suggestions.
regards,
Richard