~~NOCACHE~~
<embed en:templates:tabs_ptxdist_bootstrap>
  <label product_type>Embedded module</label>
  <label lang>en</label>
  <label mod_name>tqma335x</label>
  <label mod_name_head>TQMa335x</label>
  <label mod_arch>arm</label>
  <label bsp_name>Linux</label>
  <label bsp_name_head>Linux</label>
  <label build_system>ptxdist</label>
  <label build_system_head>PTXdist</label>
</embed>
\\



==== Clock AM335x at 800 MHz ====
Extract u-boot sources (in ptxdist use: ptxdist extract u-boot).
Then open the file include/configs/tqma335x.h
and add the following line anywhere in that file
(recommended in the CPU section at line 320):
<code>
#define CONFIG_SYS_MPUCLK	800
</code>
Then call:\\
<code>$ ptxdist drop u-boot prepare</code>
\\
\\
\\

==== Copy the image to the eMMC-Card ====

Copy the gzipped SD-Card image to the rootfs of the SD-Card:

<code>
gzip sd.hdimg
cp sd.hdimg.gz $SD_MOUNT
</code>

On the target:
<code>
dd if=sd.hdimg | gunzip | dd of=/dev/mmcblk1
</code>

Alternative: copy the running image from SD-Card to the MMC:
<code>
dd if=/dev/mmcblk0 of=/dev/mmcblk1 bs=1M count=400
</code>
\\

==== Changing display type ====

<WRAP round important 50%>
Only for BSP REV.0102
</WRAP>

3 Displays are supported in the basic configuration of the BSP. By default ETM0700 is selected in the device tree configuration.\\
To change the default display the device tree source file has to be modified, it's located inside your bsproot\\
**/platform-MBa335x/built-target/linux.x.xx/arch/arm/boot/dts/mba335x.dts**.\\
Within the CONF section at line 13 uncommend the display you would like to use.

<code>
...
11  /dts-v1/;
12
13  /* CONF - SELECT 1 (max) */
14  //#define CONFIG_ET0700		1
15  #define CONFIG_ETM0700	1
16  //#define CONFIG_CHIMEI		1
17  /* CONF END */
...
</code>

<WRAP round important 50%>
Only one Display is selectable for the basic bsp configuration
</WRAP>



==== Set RTC on STKa335x ====

There are two RTC's on the TQMa335x:
 
  * rtc0 = RTC Sitara AM335x 
  * rtc1 = RTC Module PMIC 

<WRAP round info 50%>
An optional RTC DS1339 is available for the TQMa335x module
</WRAP>

<WRAP Round important 60%>
The RTC of  the Sitara AM335x CPU is **not** usable on TQMa335x ≥ revision 0202.\\  Please see the TQMa335x user manual for further information  
</WRAP>



=== Supply RTC from licell on MBa335x === 
<WRAP round important>
To supply the RTC in PMIC please set a jumper bridge between **X3_2** and **X3_4** on MBa335x.\\  
To supply the optional RTC (DS1339) on TQMa335x please set a jumper bridge between **X3_1** and **X3_3** on MBa335x. 
</WRAP>
=== Command to set RTC0 ===
<code>hwclock -w hwclock -f /dev/rtc0 -w</code>
=== Command to read RTC0 ===
<code>hwclock -f /dev/rtc0 --show</code>
\\
=== Command to set RTC1 ===
<code>hwclock -w hwclock -f /dev/rtc1 -w</code>
=== Command to read RTC1 ===
<code>hwclock -f /dev/rtc1 --show</code>

==== Load / Change / Save the Device Tree under U-Boot ====
\\
Devicetree can be edit with the **fdt** commands under U-Boot.

<grid>
<col sm="6">
<alert type="warning" icon="fa fa-warning">
For testing purpose only. For bigger changes, please compile the Devicetree.\\ 
Therefore you can have a look at the following [[intern:general_information:tutorial:devicetree|tutorial]].
</alert> </col> </grid>

<grid>
<col sm="4">
<callout type="info" icon="true">
Tested with **Linux BSP Rev.0117 for TQMaXX**
</callout> </col> </grid>


1) At first the fdt file has to be loaded from the current boot medium (mmc) into RAM.
<code>U-Boot# run loadfdt</code>

2) Next step is to set the predefined U-Boot environment variable fdtaddr through the **fdt addr** command. 
<code>U-Boot# fdt addr $fdtaddr</code>

3) Afterwards the size of the fdt has to be increased (to the next 4K divider) in order to have some space for modifications. This is simply done by entering: 
<code>U-Boot# fdt resize </code> 

4) List device in the tree you want to change to have a look at the default settings.
++++Example|
<code>
U-Boot# fdt list /leds
leds {
        compatible = "gpio-leds";
        lvds_shtdn {
        };
        backlight {
        };
};
U-Boot# fdt print /leds
leds {
        compatible = "gpio-leds";
        lvds_shtdn {
                gpios = <0x0000003a 0x00000003 0x00000002>;
                default-state = "on";
        };
        backlight {
                gpios = <0x0000003a 0x00000004 0x00000002>;
                default-state = "on";
        };
};
</code>
++++

5) To modify a value of a propertie use the **fdt set** command.
<code>U-Boot# fdt set <path> <property> <value> </code>
++++Example|
<code>U-Boot# fdt set /leds/backlight default-state off </code>
++++

6) //Optional:// If you want to save your modified Devicetree back to mmc you'll have to run the following command:

<code>U-Boot# fatwrite mmc $bootpart $fdtaddr $fdtfile <totalsize> </code>
<wrap tip>You can find out <totalsize> of the modified fdt by entering the command **fdt header**</wrap>

Otherwise you can boot your module with the changed Devicetree right after the modification.
----
\\