From: Fu Wei fu.wei@linaro.org
This patch updates the documentation for allowing detection of an XSM module that lacks a specific compatible string. This mechanism has been added by the commit ca32012341f3de7d3975407fb963e6028f0d0c8b.
Signed-off-by: Fu Wei fu.wei@linaro.org --- v2: Improve the doc, according to the suggestion from Julien Grall.
v1: http://lists.xen.org/archives/html/xen-devel/2016-04/msg02070.html The first upstream version submitted in xen-devel mailing list.
docs/misc/arm/device-tree/booting.txt | 22 ++++++++++++++++++---- 1 file changed, 18 insertions(+), 4 deletions(-)
diff --git a/docs/misc/arm/device-tree/booting.txt b/docs/misc/arm/device-tree/booting.txt index ad98bf3..254ba77 100644 --- a/docs/misc/arm/device-tree/booting.txt +++ b/docs/misc/arm/device-tree/booting.txt @@ -24,10 +24,24 @@ Each node contains the following properties: string (which must always be present).
Xen will assume that the first module which lacks a more - specific compatible string is a "multiboot,kernel" and that - the second such is a "multiboot,ramdisk". Any subsequent - modules which lack a specific compatiblity string will not - receive any special treatment. + specific compatible string is a "multiboot,kernel". + + Xen will check all the modules for the XSM Magic from the second + module that lacks a specific compatible string. According to the + result of the detection: + - if it's a XSM, Xen will assume its compatible string is a + "xen,xsm-policy"; + - if it's not a XSM, for the second module that lacks a specific + compatible string, Xen will assume its compatible string is a + "multiboot,ramdisk"; for the third and subsequent modules those + lacks a specific compatible string will not receive any special + treatment. + This means if the ramdisk module is present and does not have the + compatible string "multiboot,ramdisk", then it must always be the + second module. + Note: This XSM Magic detection behavior was introduced by Xen 4.7. + Xen 4.6 (and downwards) still requires the XSM module to have the + compatible string "xen,xsm-policy".
Xen 4.4 supported a different set of legacy compatible strings which remain supported such that systems supporting both 4.4