From: Jayachandran C <jnair@caviumnetworks.com>
Date: Wed, 28 Feb 2018 02:52:20 -0800
Subject: watchdog: sbsa: use 32-bit read for WCV
Git-commit: 93ac3deb7c220cbcec032a967220a1f109d58431
Patch-mainline: v4.16-rc5
References: bsc#1083411
According to SBSA spec v3.1 section 5.3:
All registers are 32 bits in size and should be accessed using
32-bit reads and writes. If an access size other than 32 bits
is used then the results are IMPLEMENTATION DEFINED.
[...]
The Generic Watchdog is little-endian
The current code uses readq to read the watchdog compare register
which does a 64-bit access. This fails on ThunderX2 which does not
implement 64-bit access to this register.
Fix this by using lo_hi_readq() that does two 32-bit reads.
Signed-off-by: Jayachandran C <jnair@caviumnetworks.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Signed-off-by: Matthias Brugger <mbrugger@suse.com>
---
drivers/watchdog/sbsa_gwdt.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/watchdog/sbsa_gwdt.c b/drivers/watchdog/sbsa_gwdt.c
index 316c2eb122d2..e8bd9887c566 100644
--- a/drivers/watchdog/sbsa_gwdt.c
+++ b/drivers/watchdog/sbsa_gwdt.c
@@ -50,6 +50,7 @@
*/
#include <linux/io.h>
+#include <linux/io-64-nonatomic-lo-hi.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
@@ -159,7 +160,7 @@ static unsigned int sbsa_gwdt_get_timeleft(struct watchdog_device *wdd)
!(readl(gwdt->control_base + SBSA_GWDT_WCS) & SBSA_GWDT_WCS_WS0))
timeleft += readl(gwdt->control_base + SBSA_GWDT_WOR);
- timeleft += readq(gwdt->control_base + SBSA_GWDT_WCV) -
+ timeleft += lo_hi_readq(gwdt->control_base + SBSA_GWDT_WCV) -
arch_counter_get_cntvct();
do_div(timeleft, gwdt->clk);
--
2.16.2