README: Change open window commands to return actual flash offset
The open window commands now return in part of the response the
acutal flash offset which the window maps. That is the actual
flash offset returned is the flash offset of the data which will
be presented at the lpc bus address returned.
Additionally deprecate the window size fields in get_mbox_info as
the window size is no longer fixed or required to be consistent
between windows.
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Change-Id: Ib170d96e66a5f6eb8bc070e56dfe78f1a6b26e57
diff --git a/README.md b/README.md
index 8640bd6..1a29648 100644
--- a/README.md
+++ b/README.md
@@ -395,8 +395,8 @@
V2:
Args 0: API version
- Args 1-2: default read window size (blocks)
- Args 3-4: default write window size (blocks)
+ Args 1-2: reserved
+ Args 3-4: reserved
Args 5: Block size as power of two (encoded as a shift)
Command:
@@ -433,6 +433,7 @@
V2:
Args 0-1: LPC bus address of window (blocks)
Args 2-3: Actual window size (blocks)
+ Args 4-5: Actual window location as offset into flash (blocks)
Notes:
Window location is always given as an offset into flash as
taken from the start of flash - that is it is an absolute
@@ -447,6 +448,15 @@
of the request. The host must not access past the end of the
active window.
+ The actual window location indicates the absolute flash offset
+ that the window actually maps and is not required to be equal
+ to the flash offset requested by the host, but however must be
+ less than or equal to it. Thus the first block of the window at
+ the lpc address in the response will map the first block at the
+ actual flash offset also contained in the response. It is the
+ responsibility of the host to use this information to access
+ any offset which is required.
+
The requested window size may be zero. In this case the
BMC is free to create any sized window but it must contain
atleast the first block of data requested by the host. A large