Kernel/linux-stable
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git synced 2025-01-10 07:00:48 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

ARM: mvebu: use the virtual CPU registers to access coherency registers

Browse Source 
The Armada XP provides a mechanism called "virtual CPU registers" or
"per-CPU register banking", to access the per-CPU registers of the
current CPU, without having to worry about finding on which CPU we're
running. CPU0 has its registers at 0x21800, CPU1 at 0x21900, CPU2 at
0x21A00 and CPU3 at 0x21B00. The virtual registers accessing the
current CPU registers are at 0x21000.

However, in the Device Tree node that provides the register addresses
for the coherency unit (which is responsible for ensuring coherency
between processors, and I/O coherency between processors and the
DMA-capable devices), a mistake was made: the CPU0-specific registers
were specified instead of the virtual CPU registers. This means that
the coherency barrier needed for I/O coherency was not behaving
properly when executed from a CPU different from CPU0. This patch
fixes that by using the virtual CPU registers.

Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: <stable@vger.kernel.org> # v3.8+
Fixes: e60304f8cb7bb5 "arm: mvebu: Add hardware I/O Coherency support"
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
This commit is contained in:
Gregory CLEMENT 2013-11-25 17:26:46 +01:00 committed by Jason Cooper
parent 2163e61c92
commit b6dda00cdd
1 changed files with 1 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
arch/arm/boot/dts/armada-370-xp.dtsi
View File

@ -118,7 +118,7 @@
coherency-fabric@20200 {
compatible = "marvell,coherency-fabric";
reg = <0x20200 0xb0>, <0x21810 0x1c>;
reg = <0x20200 0xb0>, <0x21010 0x1c>;
};
serial@12000 {