topic earlycon on imx6sx Linux in i.MX Processors https://community.nxp.com/t5/i-MX-Processors/earlycon-on-imx6sx-Linux/m-p/891111#M134731 <HTML><HEAD></HEAD><BODY><P>I am trying to enable earlycon on imx6sx. I appended "earlycon=ec_imx21,0x02020000,1152008n" string to the kernel parameter passed from uboot to the kernel.&nbsp; Indeed, this enabled the early console, but unfortunately, text output became garbled on my terminal:</P><P></P><P><STRONG>setenv mmcargs setenv bootargs console=\${console},\${baudrate} root=/dev/mmcblk3p2 rootwait rw earlycon=ec_imx21,0x02020000,115200n8</STRONG><BR />=&gt; saveenv<BR />Saving Environment to MMC...<BR />Writing to MMC(2)... done<BR />=&gt;<BR />=&gt; boot<BR />----------------------------------------------<BR />Kernel image @ 0x80800000 [ 0x000000 - 0x458180 ]<BR />## Flattened Device Tree blob at 83000000<BR /> Booting using the fdt blob at 0x83000000<BR /> Using Device Tree in place at 83000000, end 8300f6fb<BR />switch to ldo_bypass mode!</P><P></P><P>Starting kernel ...</P><P></P><P>Uncompressing Linux... done, booting the kernel.<BR />[ 0.000000] Booting Linux on physical CPU 0x0<BR />[ 0.000000] Linux version 4.9.88-rt66-gf5546cd-dirty (warkene@lbnidevlinux01) (gcc version 7.3.0 (GCC) ) #9 SMP PREEMPT RT Tue Apr 23 16:08:54 CDT 2019<BR />[ 0.000000] CPU: ARMv7 Processor [412fc09a] revision 10 (ARMv7), cr=10c53c7d<BR />[ 0.000000] CPU: PIPT / VIPT nonaliasing data cache, VIPT aliasing instruction cache<BR />[ 0.000000] OF: fdt:Machine model: Freescale i.MX6 SoloX SDB RevB Board (Shure Blackhawk DSM eval)<BR />[ 0.000000]<STRONG> earlycon: ec_imx21 at MMIO 0x02020000 (options '115200n8')</STRONG><BR /><STRONG>ûÂðôo9!Dé`Û</STRONG><BR /><STRONG> ÿ</STRONG><BR /><STRONG> / Éâýä'»?K¡º(?Û</STRONG></P><P><STRONG>----------------------------------</STRONG></P><P><STRONG>[ 5.679913] console [ttymxc0] enabled</STRONG><BR />[ 5.684709] bootconsole [ec_imx21] disabled<BR />[ 5.684709] bootconsole [ec_imx21] disabled<BR />[ 5.709531] 21f4000.serial: ttymxc4 at MMIO 0x21f4000 (irq = 71, base_baud = 5000000) is a IMX<BR />[ 5.752225] imx sema4 driver is registered.</P><P>------------------------------------</P><P></P><P>It looks like baud rate was not set correctly?</P><P></P><P><SPAN style="color: #222222; background-color: #ffffff;">Any help you can give will be greatly appreciated.</SPAN></P><P></P><P><SPAN style="color: #222222; background-color: #ffffff;">Regards,</SPAN></P><P><SPAN style="color: #222222; background-color: #ffffff;">Eugen W.</SPAN></P></BODY></HTML> Wed, 24 Apr 2019 22:24:15 GMT eugenwarkentin 2019-04-24T22:24:15Z earlycon on imx6sx Linux https://community.nxp.com/t5/i-MX-Processors/earlycon-on-imx6sx-Linux/m-p/891111#M134731 <HTML><HEAD></HEAD><BODY><P>I am trying to enable earlycon on imx6sx. I appended "earlycon=ec_imx21,0x02020000,1152008n" string to the kernel parameter passed from uboot to the kernel.&nbsp; Indeed, this enabled the early console, but unfortunately, text output became garbled on my terminal:</P><P></P><P><STRONG>setenv mmcargs setenv bootargs console=\${console},\${baudrate} root=/dev/mmcblk3p2 rootwait rw earlycon=ec_imx21,0x02020000,115200n8</STRONG><BR />=&gt; saveenv<BR />Saving Environment to MMC...<BR />Writing to MMC(2)... done<BR />=&gt;<BR />=&gt; boot<BR />----------------------------------------------<BR />Kernel image @ 0x80800000 [ 0x000000 - 0x458180 ]<BR />## Flattened Device Tree blob at 83000000<BR /> Booting using the fdt blob at 0x83000000<BR /> Using Device Tree in place at 83000000, end 8300f6fb<BR />switch to ldo_bypass mode!</P><P></P><P>Starting kernel ...</P><P></P><P>Uncompressing Linux... done, booting the kernel.<BR />[ 0.000000] Booting Linux on physical CPU 0x0<BR />[ 0.000000] Linux version 4.9.88-rt66-gf5546cd-dirty (warkene@lbnidevlinux01) (gcc version 7.3.0 (GCC) ) #9 SMP PREEMPT RT Tue Apr 23 16:08:54 CDT 2019<BR />[ 0.000000] CPU: ARMv7 Processor [412fc09a] revision 10 (ARMv7), cr=10c53c7d<BR />[ 0.000000] CPU: PIPT / VIPT nonaliasing data cache, VIPT aliasing instruction cache<BR />[ 0.000000] OF: fdt:Machine model: Freescale i.MX6 SoloX SDB RevB Board (Shure Blackhawk DSM eval)<BR />[ 0.000000]<STRONG> earlycon: ec_imx21 at MMIO 0x02020000 (options '115200n8')</STRONG><BR /><STRONG>ûÂðôo9!Dé`Û</STRONG><BR /><STRONG> ÿ</STRONG><BR /><STRONG> / Éâýä'»?K¡º(?Û</STRONG></P><P><STRONG>----------------------------------</STRONG></P><P><STRONG>[ 5.679913] console [ttymxc0] enabled</STRONG><BR />[ 5.684709] bootconsole [ec_imx21] disabled<BR />[ 5.684709] bootconsole [ec_imx21] disabled<BR />[ 5.709531] 21f4000.serial: ttymxc4 at MMIO 0x21f4000 (irq = 71, base_baud = 5000000) is a IMX<BR />[ 5.752225] imx sema4 driver is registered.</P><P>------------------------------------</P><P></P><P>It looks like baud rate was not set correctly?</P><P></P><P><SPAN style="color: #222222; background-color: #ffffff;">Any help you can give will be greatly appreciated.</SPAN></P><P></P><P><SPAN style="color: #222222; background-color: #ffffff;">Regards,</SPAN></P><P><SPAN style="color: #222222; background-color: #ffffff;">Eugen W.</SPAN></P></BODY></HTML> Wed, 24 Apr 2019 22:24:15 GMT https://community.nxp.com/t5/i-MX-Processors/earlycon-on-imx6sx-Linux/m-p/891111#M134731 eugenwarkentin 2019-04-24T22:24:15Z Re: earlycon on imx6sx Linux https://community.nxp.com/t5/i-MX-Processors/earlycon-on-imx6sx-Linux/m-p/891112#M134732 <HTML><HEAD></HEAD><BODY><P>There should be nothing special to earlycon.<BR />Please make sure that you are set the same serial port options (baud rate, flow control, etc) in bootargs and terminal running on the PC.<BR /> <BR /> <BR />Have a great day,<BR />Victor<BR /> <BR />-----------------------------------------------------------------------------------------------------------------------<BR />Note: If this post answers your question, please click the Correct Answer button. Thank you!<BR />-----------------------------------------------------------------------------------------------------------------------</P></BODY></HTML> Thu, 25 Apr 2019 02:01:34 GMT https://community.nxp.com/t5/i-MX-Processors/earlycon-on-imx6sx-Linux/m-p/891112#M134732 b36401 2019-04-25T02:01:34Z