From: Magnus Damm <damm@opensource.se>
Date: Fri, 14 Dec 2012 05:54:37 +0000 (+0900)
Subject: clocksource: sh_cmt: Add CMT register layout comment
X-Git-Tag: next-20130218~14^2^6
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=387ab8430c759ab99bfea2a0300d0c6c6a6e125f;p=karo-tx-linux.git

clocksource: sh_cmt: Add CMT register layout comment

Add a comment about different register layouts
supported by the CMT driver.

Signed-off-by: Magnus Damm <damm@opensource.se>
Acked-by: John Stultz <john.stultz@linaro.org>
Tested-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
---

diff --git a/drivers/clocksource/sh_cmt.c b/drivers/clocksource/sh_cmt.c
index 7108963a6ab8..b72b7242125e 100644
--- a/drivers/clocksource/sh_cmt.c
+++ b/drivers/clocksource/sh_cmt.c
@@ -66,6 +66,21 @@ struct sh_cmt_priv {
 			    unsigned long value);
 };
 
+/* Examples of supported CMT timer register layouts and I/O access widths:
+ *
+ * "16-bit counter and 16-bit control" as found on sh7263:
+ * CMSTR 0xfffec000 16-bit
+ * CMCSR 0xfffec002 16-bit
+ * CMCNT 0xfffec004 16-bit
+ * CMCOR 0xfffec006 16-bit
+ *
+ * "32-bit counter and 16-bit control" as found on sh7372, sh73a0, r8a7740:
+ * CMSTR 0xffca0000 16-bit
+ * CMCSR 0xffca0060 16-bit
+ * CMCNT 0xffca0064 32-bit
+ * CMCOR 0xffca0068 32-bit
+ */
+
 static unsigned long sh_cmt_read16(void __iomem *base, unsigned long offs)
 {
 	return ioread16(base + (offs << 1));