dma: mv_xor: clear the window override control registers
The XOR channels on Marvell SoCs have a Window Override Control
register that allow to do some fancy things with addresses. Those
features are not used by the driver, but some U-Boot versions anyway
modify those registers.
For some reason, the U-Boot on OpenBlocks AX3-4 was setting an invalid
value in those registers when the addition 2 GB DRAM chip was plugged
into the board, causing the XOR driver to fail in using the XOR
engines.
By setting those registers to 0 during the driver initialization, we
ensure that the registers are configured according with the driver
operation model.
Thanks to Lior Amsalem <alior@marvell.com> for his help in debugging
this problem.
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
diff --git a/drivers/dma/mv_xor.h b/drivers/dma/mv_xor.h
index 1704328..c632a47 100644
--- a/drivers/dma/mv_xor.h
+++ b/drivers/dma/mv_xor.h
@@ -53,6 +53,7 @@
#define WINDOW_SIZE(w) (0x270 + ((w) << 2))
#define WINDOW_REMAP_HIGH(w) (0x290 + ((w) << 2))
#define WINDOW_BAR_ENABLE(chan) (0x240 + ((chan) << 2))
+#define WINDOW_OVERRIDE_CTRL(chan) (0x2A0 + ((chan) << 2))
struct mv_xor_device {
void __iomem *xor_base;