Merge tag 'mvebu-fixes-3.19-4' of git://git.infradead.org/linux-mvebu…

… into fixes Merge "mvebu/fixes openSUSE#3" from Andrew Lunn: mvebu fixes for 3.19. (Part 4) bus: mvebu-mbus: fix support of MBus window 13 * tag 'mvebu-fixes-3.19-4' of git://git.infradead.org/linux-mvebu: bus: mvebu-mbus: fix support of MBus window 13 ARM: mvebu: completely disable hardware I/O coherency Signed-off-by: Olof Johansson <[email protected]>
goldwynr · Jan 23, 2015 · 5cf9206 · 5cf9206
2 parents 604beee + 38bdf45
commit 5cf9206
Showing 1 changed file with 13 additions and 0 deletions.
diff --git a/drivers/bus/mvebu-mbus.c b/drivers/bus/mvebu-mbus.c
@@ -210,12 +210,25 @@ 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);
 }