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authorLinus Torvalds <torvalds@linux-foundation.org>2014-01-25 10:49:30 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2014-01-25 10:49:30 -0800
commit9b83d851a2bdd021e2135999e5bce3eb8fef94e6 (patch)
treeb8703e813b1d8d66fb262cd757f54f3c05966d50 /Documentation
parent2d08cd0ef89a24f5eb6c6801c48cd06bca230d6d (diff)
parent9ed82c6866e2ab671935a75ea454047e8bddb177 (diff)
Merge tag 'xtensa-next-20140123' of git://github.com/czankel/xtensa-linux
Pull Xtensa patches from Chris Zankel: "The major changes are adding support for SMP for Xtensa, fixing and cleaning up the ISS (simulator) network driver, and better support for device trees" * tag 'xtensa-next-20140123' of git://github.com/czankel/xtensa-linux: (40 commits) xtensa: implement ndelay xtensa: clean up udelay xtensa: enable HAVE_PERF_EVENTS xtensa: remap io area defined in device tree xtensa: support default device tree buses xtensa: initialize device tree clock sources xtensa: xtfpga: fix definitions of platform devices xtensa: standardize devicetree cpu compatible strings xtensa: avoid duplicate of IO range definitions xtensa: fix ATOMCTL register documentation xtensa: Enable irqs after cpu is set online xtensa: ISS: raise network polling rate to 10 times/sec xtensa: remove unused XTENSA_ISS_NETWORK Kconfig parameter xtensa: ISS: avoid simple_strtoul usage xtensa: Switch to sched_clock_register() xtensa: implement CPU hotplug xtensa: add SMP support xtensa: add MX irqchip xtensa: clear timer IRQ unconditionally in its handler xtensa: clean up do_interrupt/do_IRQ ...
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/xtensa/atomctl.txt2
-rw-r--r--Documentation/xtensa/mmu.txt18
2 files changed, 19 insertions, 1 deletions
diff --git a/Documentation/xtensa/atomctl.txt b/Documentation/xtensa/atomctl.txt
index 10a8d1ff35ec..1da783ac200c 100644
--- a/Documentation/xtensa/atomctl.txt
+++ b/Documentation/xtensa/atomctl.txt
@@ -40,5 +40,5 @@ See Section 4.3.12.4 of ISA; Bits:
--------- --------------- ----------------- ----------------
0 Exception Exception Exception
1 RCW Transaction RCW Transaction RCW Transaction
- 2 Internal Operation Exception Reserved
+ 2 Internal Operation Internal Operation Reserved
3 Reserved Reserved Reserved
diff --git a/Documentation/xtensa/mmu.txt b/Documentation/xtensa/mmu.txt
index 2b1af7606d57..0312fe66475c 100644
--- a/Documentation/xtensa/mmu.txt
+++ b/Documentation/xtensa/mmu.txt
@@ -44,3 +44,21 @@ After step 4, we jump to intended (linked) address of this code.
40..5F -> 40 40..5F -> pc -> pc 40..5F -> pc
20..3F -> 20 -> 20 20..3F -> 20
00..1F -> 00 -> 00 00..1F -> 00
+
+The default location of IO peripherals is above 0xf0000000. This may change
+using a "ranges" property in a device tree simple-bus node. See ePAPR 1.1, ยง6.5
+for details on the syntax and semantic of simple-bus nodes. The following
+limitations apply:
+
+1. Only top level simple-bus nodes are considered
+
+2. Only one (first) simple-bus node is considered
+
+3. Empty "ranges" properties are not supported
+
+4. Only the first triplet in the "ranges" property is considered
+
+5. The parent-bus-address value is rounded down to the nearest 256MB boundary
+
+6. The IO area covers the entire 256MB segment of parent-bus-address; the
+ "ranges" triplet length field is ignored