[bootlin/training-materials updates] master: slides/sysdev-bootloaders-u-boot: simplify "installing U-Boot" slide (64cb6081)

[Michael Opdenacker]

Repository : https://github.com/bootlin/training-materials
On branch  : master
Link       : https://github.com/bootlin/training-materials/commit/64cb60818aca44be920c8869c5d14eebde23db72

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

commit 64cb60818aca44be920c8869c5d14eebde23db72
Author: Michael Opdenacker <michael.opdenacker at bootlin.com>
Date:   Wed Jul 26 10:24:53 2023 +0200

    slides/sysdev-bootloaders-u-boot: simplify "installing U-Boot" slide
    
    - In particular by referring to Snagboot
    
    Signed-off-by: Michael Opdenacker <michael.opdenacker at bootlin.com>


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

64cb60818aca44be920c8869c5d14eebde23db72
 .../sysdev-bootloaders-u-boot.tex                  | 25 +++++++++-------------
 1 file changed, 10 insertions(+), 15 deletions(-)

diff --git a/slides/sysdev-bootloaders-u-boot/sysdev-bootloaders-u-boot.tex b/slides/sysdev-bootloaders-u-boot/sysdev-bootloaders-u-boot.tex
index 46dc638b..489ad270 100644
--- a/slides/sysdev-bootloaders-u-boot/sysdev-bootloaders-u-boot.tex
+++ b/slides/sysdev-bootloaders-u-boot/sysdev-bootloaders-u-boot.tex
@@ -219,22 +219,17 @@ $ make DEVICE_TREE=am335x-boneblack-wireless CROSS_COMPILE=arm-linux-
   \end{itemize}
 \end{frame}
 
-\begin{frame}{Installing U-Boot in flash (NAND or eMMC)}
-  Different possibilities depending on the hardware:
+\begin{frame}{Installing U-Boot}
   \begin{enumerate}
-  \item The ROM code provides some kind of specific boot monitor with
-    which you can communicate through the serial port or USB using a
-    specific protocol, to flash U-Boot.
-  \item The CPU boots first on removable media (SD card) before
-    booting from fixed media. In this case, boot from
-    removable media to reflash a new version.
-  \item U-Boot is already installed, and can be used to flash a new
-    version of itself. If the new version of U-Boot doesn't work,
-    you will have to reflash it through another method (it is always
-    possible through an external SD card).
-  \item The board provides a JTAG interface, which allows to write to
-    the flash memory remotely, without any system running on the
-    board.
+  \item If U-Boot is loaded from external storage, just update
+        the binaries on such storage.
+  \item If U-Boot is loaded from internal storage (eMMC or NAND),
+        you can update it using {\em Snagboot}
+        (\url{https://github.com/bootlin/snagboot}) if it supports
+        your SoC, or with the custom solution from the SoC vendor.
+  \item An alternative is to reflash internal storage with JTAG
+        (if available), but that's more complicated and requires
+        a JTAG probe.
   \end{enumerate}
 \end{frame}