bus: mvebu-mbus: do not set WIN_CTRL_SYNCBARRIER on non io-coherent platforms.
Commit a0b5cd4ac2d6 ("bus: mvebu-mbus: use automatic I/O
synchronization barriers") enabled the usage of automatic I/O
synchronization barriers by enabling bit WIN_CTRL_SYNCBARRIER in the
control registers of MBus windows, but on non io-coherent platforms
(orion5x, kirkwood and dove) the WIN_CTRL_SYNCBARRIER bit in
the window control register is either reserved (all windows except 6
and 7) or enables read-only protection (windows 6 and 7).
Signed-off-by: Nicolas Schichan <nschichan@freebox.fr>
Reviewed-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: <stable@vger.kernel.org> # v4.0+
Fixes: a0b5cd4ac2d6 ("bus: mvebu-mbus: use automatic I/O synchronization barriers")
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
diff --git a/drivers/bus/mvebu-mbus.c b/drivers/bus/mvebu-mbus.c
index fb9ec62..7fa4510 100644
--- a/drivers/bus/mvebu-mbus.c
+++ b/drivers/bus/mvebu-mbus.c
@@ -70,6 +70,7 @@
*/
#define WIN_CTRL_OFF 0x0000
#define WIN_CTRL_ENABLE BIT(0)
+/* Only on HW I/O coherency capable platforms */
#define WIN_CTRL_SYNCBARRIER BIT(1)
#define WIN_CTRL_TGT_MASK 0xf0
#define WIN_CTRL_TGT_SHIFT 4
@@ -323,8 +324,9 @@
ctrl = ((size - 1) & WIN_CTRL_SIZE_MASK) |
(attr << WIN_CTRL_ATTR_SHIFT) |
(target << WIN_CTRL_TGT_SHIFT) |
- WIN_CTRL_SYNCBARRIER |
WIN_CTRL_ENABLE;
+ if (mbus->hw_io_coherency)
+ ctrl |= WIN_CTRL_SYNCBARRIER;
writel(base & WIN_BASE_LOW, addr + WIN_BASE_OFF);
writel(ctrl, addr + WIN_CTRL_OFF);