doc: driver-model: Convert of-plat.txt to reST

[oweals/u-boot.git] / doc / README.qemu-arm

diff --git a/doc/README.qemu-arm b/doc/README.qemu-arm
index aee789447aea39a5ed40129c4582c6a8db6912a4..e67bc13f70151a1e097234086766811f1ecfc9f4 100644 (file)
--- a/doc/README.qemu-arm
+++ b/doc/README.qemu-arm
@@ -1,8 +1,6 @@
+# SPDX-License-Identifier: GPL-2.0+
 #
 # Copyright (C) 2017, Tuomas Tynkkynen <tuomas.tynkkynen@iki.fi>
-#
-# SPDX-License-Identifier:     GPL-2.0+
-#
 
 U-Boot on QEMU's 'virt' machine on ARM & AArch64
 ================================================
@@ -41,15 +39,20 @@ Running U-Boot
 The minimal QEMU command line to get U-Boot up and running is:
 
 - For ARM:
-    qemu-system-arm -machine virt,highmem=off -bios u-boot.bin
+    qemu-system-arm -machine virt -bios u-boot.bin
 
 - For AArch64:
-    qemu-system-aarch64 -machine virt,highmem=off -cpu cortex-a57 -bios u-boot.bin
+    qemu-system-aarch64 -machine virt -cpu cortex-a57 -bios u-boot.bin
 
-The 'highmem=off' parameter to the 'virt' machine is required for PCI to work
-in U-Boot. Also, for some odd reason qemu-system-aarch64 needs to be explicitly
+Note that for some odd reason qemu-system-aarch64 needs to be explicitly
 told to use a 64-bit CPU or it will boot in 32-bit mode.
 
+Additional persistent U-boot environment support can be added as follows:
+- Create envstore.img using qemu-img:
+    qemu-img create -f raw envstore.img 64M
+- Add a pflash drive parameter to the command line:
+    -drive if=pflash,format=raw,index=1,file=envstore.img
+
 Additional peripherals that have been tested to work in both U-Boot and Linux
 can be enabled with the following command line parameters: