Add explicit device access check before performing device enumeration.
This gives a chance to clear possible link error conditions by issuing safe
maintenance read request(s).
Signed-off-by: Alexandre Bounine <alexandre.boun...@idt.com>
Reviewed-by: Thomas Moll <thomas.m...@sysgo.com>
Cc: Matt Porter <mpor...@kernel.crashing.org>
Cc: Li Yang <le...@freescale.com>
Cc: Kumar Gala <ga...@kernel.crashing.org>
---
drivers/rapidio/rio-scan.c | 6 ++++++
drivers/rapidio/rio.c | 2 +-
drivers/rapidio/rio.h | 2 ++
3 files changed, 9 insertions(+), 1 deletions(-)
diff --git a/drivers/rapidio/rio-scan.c b/drivers/rapidio/rio-scan.c
index 5dc33d1..fb5324b 100644
--- a/drivers/rapidio/rio-scan.c
+++ b/drivers/rapidio/rio-scan.c
@@ -761,6 +761,12 @@ static int __devinit rio_enum_peer(struct rio_net *net,
struct rio_mport *port,
u16 destid;
int tmp;
+ if (rio_mport_chk_dev_access(port,
+ RIO_ANY_DESTID(port->sys_size), hopcount)) {
+ pr_debug("RIO: device access check failed\n");
+ return -1;
+ }
+
if (rio_get_host_deviceid_lock(port, hopcount) == port->host_deviceid) {
pr_debug("RIO: PE already discovered by this host\n");
/*
diff --git a/drivers/rapidio/rio.c b/drivers/rapidio/rio.c
index 22f7847..9621a7b 100644
--- a/drivers/rapidio/rio.c
+++ b/drivers/rapidio/rio.c
@@ -544,7 +544,7 @@ rio_chk_dev_route(struct rio_dev *rdev, struct rio_dev
**nrdev, int *npnum)
* @destid: Device destination ID in network
* @hopcount: Number of hops into the network
*/
-static int
+int
rio_mport_chk_dev_access(struct rio_mport *mport, u16 destid, u8 hopcount)
{
int i = 0;
diff --git a/drivers/rapidio/rio.h b/drivers/rapidio/rio.h
index bc71ba1..d249a12 100644
--- a/drivers/rapidio/rio.h
+++ b/drivers/rapidio/rio.h
@@ -24,6 +24,8 @@ extern u32 rio_mport_get_physefb(struct rio_mport *port, int
local,
u16 destid, u8 hopcount);
extern u32 rio_mport_get_efb(struct rio_mport *port, int local, u16 destid,
u8 hopcount, u32 from);
+extern int rio_mport_chk_dev_access(struct rio_mport *mport, u16 destid,
+ u8 hopcount);
extern int rio_create_sysfs_dev_files(struct rio_dev *rdev);
extern int rio_enum_mport(struct rio_mport *mport);
extern int rio_disc_mport(struct rio_mport *mport);
--
1.7.0.5
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