[bootlin/training-materials updates] master: Flash filesystems: misc improvements (6963cc52)

[Michael Opdenacker]

Repository : https://github.com/bootlin/training-materials
On branch  : master
Link       : https://github.com/bootlin/training-materials/commit/6963cc52f69e48e5d20178aa705093909233e921

>---------------------------------------------------------------

commit 6963cc52f69e48e5d20178aa705093909233e921
Author: Michael Opdenacker <michael.opdenacker at bootlin.com>
Date:   Wed Aug 5 10:16:03 2020 +0200

    Flash filesystems: misc improvements
    
    - Correct UBI image creation workflow diagram
      (separate DTB and Kernel)
    
    - Add details about "rootfstype="
    
    Signed-off-by: Michael Opdenacker <michael.opdenacker at bootlin.com>


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6963cc52f69e48e5d20178aa705093909233e921
 .../sysdev-flash-filesystems.tex                      |   6 ++++++
 .../ubi-creation-workflow.dia                         | Bin 1949 -> 2114 bytes
 2 files changed, 6 insertions(+)

diff --git a/slides/sysdev-flash-filesystems/sysdev-flash-filesystems.tex b/slides/sysdev-flash-filesystems/sysdev-flash-filesystems.tex
index 7874f259..370f0ed2 100644
--- a/slides/sysdev-flash-filesystems/sysdev-flash-filesystems.tex
+++ b/slides/sysdev-flash-filesystems/sysdev-flash-filesystems.tex
@@ -562,6 +562,7 @@ setenv mtdparts mtdparts=omap2-nand.0:512k(XLoader)ro,1536k(UBoot)ro,512k(Env),4
   \item A read-only UBIFS filesystem can go in a \code{static}
 	volume, but in this case \code{dynamic} volumes are best
         for performance (CRC checking also done at UBIFS level).
+  \item \code{autoresize}: allows to fill all remaining UBI space
   \end{itemize}
   \begin{columns}
     \column{0.33\textwidth}
@@ -736,6 +737,11 @@ vol_flags=autoresize
       Attach \code{/dev/mtd1} to the UBI layer and create \code{ubi0}
     \item \code{rootfstype=ubifs root=ubi0:rootfs}\\
       Mount the \code{rootfs} volume on ubi0 as a UBIFS filesystem
+    \item \code{rootfstype=} lets the kernel know what filesystem
+      to mount as root filesystem. It's mandatory for UBIFS, but
+      it can also be used for block filesystems. This way the kernel
+      doesn't have to try all the filesystems it supports. This reduces
+      boot time.
     \end{itemize}
   \item Example: \code{rootfstype=ubifs ubi.mtd=1 root=ubi0:rootfs}
   \end{itemize}
diff --git a/slides/sysdev-flash-filesystems/ubi-creation-workflow.dia b/slides/sysdev-flash-filesystems/ubi-creation-workflow.dia
index f7ae116a..c766d997 100644
Binary files a/slides/sysdev-flash-filesystems/ubi-creation-workflow.dia and b/slides/sysdev-flash-filesystems/ubi-creation-workflow.dia differ