Return/add section about target hardware and kernel selection.

Signed-off-by: Pavel Pisa <pisa@cmp.felk.cvut.cz>

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@@ -70,6 +70,33 @@ for this driver can be found
 on <a href="http://rtime.felk.cvut.cz/hw/index.php/Humusoft_MF6xx">DCE
 HW Wiki page</a>.</p>
 
+<h2 id="platformselect">RT-Capable Platform and Kernel</h2>
+
+Standard distribution Linux kernel does not guarantee bounded latencies for many operations.
+The use of <a href="http://rt.wiki.kernel.org/">real-time variant</a> of <a href="http://en.wikipedia.org/wiki/Linux">Linux</a>
+kernel is required to make system durable. This kernel variants minimizes regions
+where switch to the highest priority (i.e. Linux ERT generated) task is blocked by
+kernel when servicing system calls for other tasks.
+
+Selection of the right version of the kernel is not enough for non-disruptive
+operation. Computer system hardware selection is critical as well. The system
+has to provide enough computational power for compiled in blocks data evaluation
+evaluation and Linux kernel services processing. Other critical disturbance sources
+are hardware caused latencies and lags in a program processing by CPU. The source
+can be bus systems load by other subsystems (i.e. graphic processor memory access,
+peripheral DMA - SSD, SD-card, Flash controller etc.). The other critical source of
+latencies in x86 based systems is <a href="http://en.wikipedia.org/wiki/System_Management_Mode">SMI</a>
+processing. The SMI enable and processing is under BIOS and motherboard vendor control
+and this problem cannot be resolved by operating system. This means that proper
+hardware selection is critical.
+
+A long period evaluation data of different combinations of Linux kernel version
+runing on many CPU architectures and boards from many vendors is (see <a href="http://www.osadl.org/">OSADL</a>
+<a href="http://www.osadl.org/Quality-assurance-at-the-OSADL-QA-Farm.osadl-services-qa.0.html">Quality Assurance Farm</a>)
+
+According to these track records carefully selected x86 or embedded GNU/Linux system can run
+real-time tasks with sampling frequencies up to 20&nbsp;kHz with no losing sample per months.
+
 <h2 id="download">Source Code and Download</h2>
 
 <dl>