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authorAndrew Lunn <andrew@lunn.ch>2015-01-18 09:46:10 -0600
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2015-01-29 17:40:44 -0800
commit3436c0aadcc5827fcce5ef3b33d4d523720f7137 (patch)
tree74426851f5543ec6c6b199d1a3ff1b95a8a01e56
parent1f20756ce695ee56c2899e95757497d9c1cc8bbb (diff)
bus: mvebu-mbus: fix support of MBus window 13
commit 38bdf45f4aa5cb6186d50a29e6cbbd9d486a1519 upstream. On Armada XP, 375 and 38x the MBus window 13 has the remap capability, like windows 0 to 7. However, the mvebu-mbus driver isn't currently taking into account this special case, which means that when window 13 is actually used, the remap registers are left to 0, making the device using this MBus window unavailable. As a minimal fix for stable, don't use window 13. A full fix will follow later. Fixes: fddddb52a6c ("bus: introduce an Marvell EBU MBus driver") Reviewed-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com> Signed-off-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r--drivers/bus/mvebu-mbus.c13
1 files changed, 13 insertions, 0 deletions
diff --git a/drivers/bus/mvebu-mbus.c b/drivers/bus/mvebu-mbus.c
index 26c3779d871d..d29f5ffdb0f4 100644
--- a/drivers/bus/mvebu-mbus.c
+++ b/drivers/bus/mvebu-mbus.c
@@ -182,12 +182,25 @@ static void mvebu_mbus_disable_window(struct mvebu_mbus_state *mbus,
}
/* Checks whether the given window number is available */
+
+/* On Armada XP, 375 and 38x the MBus window 13 has the remap
+ * capability, like windows 0 to 7. However, the mvebu-mbus driver
+ * isn't currently taking into account this special case, which means
+ * that when window 13 is actually used, the remap registers are left
+ * to 0, making the device using this MBus window unavailable. The
+ * quick fix for stable is to not use window 13. A follow up patch
+ * will correctly handle this window.
+*/
static int mvebu_mbus_window_is_free(struct mvebu_mbus_state *mbus,
const int win)
{
void __iomem *addr = mbus->mbuswins_base +
mbus->soc->win_cfg_offset(win);
u32 ctrl = readl(addr + WIN_CTRL_OFF);
+
+ if (win == 13)
+ return false;
+
return !(ctrl & WIN_CTRL_ENABLE);
}