diff patches/bootloader-disable.patch @ 10:8604a725d883

bootloader-disable.patch implemented
author Space Falcon <falcon@ivan.Harhan.ORG>
date Sat, 06 Jun 2015 07:52:36 +0000
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/patches/bootloader-disable.patch	Sat Jun 06 07:52:36 2015 +0000
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+# TI's TCS211 firmware includes a component called "bootloader" which executes
+# before the main fw and seems to provide a mechanism for interrupting and
+# diverting the regular boot process by sending some magic into one of the
+# UARTs, replicating the equivalent functionality provided by the Calypso boot
+# ROM.  However, we never got the source for this part, only a binary object
+# library, so it is not immediately apparent exactly what this bootloader does,
+# what the communication protocol is and so forth - and I (Space Falcon) don't
+# feel like reverse-engineering this piece as the needed functionality is
+# provided much more usefully (unbrickable!) by the boot ROM in the chip.
+#
+# If one does not wish to run code for which we have no source and which we
+# therefore don't really understand, the present patch disables the TCS211
+# bootloader by smacking a "bx lr" Thumb instruction at the
+# $sta_select_application entry point to the code for which we have no source.
+
+[start.obj]
+
+.text 16a 70
+.text 16b 47