[PATCH 14/14] coresight: configuring ETF in FIFO mode when acting as link

From: Mathieu Poirier
Date: Tue Mar 22 2016 - 16:24:28 EST


When part of a path but not identified as a sink, the EFT has to
be configured as a link and placed in HW FIFO mode. As such when
enabling a path, call the right configuration function based on
the role the ETF if playing in this trace run.

Signed-off-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
---
drivers/hwtracing/coresight/coresight.c | 17 +++++++++++++++--
1 file changed, 15 insertions(+), 2 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight.c b/drivers/hwtracing/coresight/coresight.c
index 6ec2b66af9ee..fa7ecbd99901 100644
--- a/drivers/hwtracing/coresight/coresight.c
+++ b/drivers/hwtracing/coresight/coresight.c
@@ -287,15 +287,27 @@ int coresight_enable_path(struct list_head *path, u32 mode)
{

int ret = 0;
+ u32 type;
struct coresight_node *nd;
struct coresight_device *csdev, *parent, *child;

list_for_each_entry_reverse(nd, path, link) {
csdev = nd->csdev;
+ type = csdev->type;

- switch (csdev->type) {
+ /*
+ * ETF devices are tricky... They can be a link or a sink,
+ * depending on how they are configured. If an ETF has been
+ * "activated" it will be configured as a sink, otherwise
+ * go ahead with the link configuration.
+ */
+ if (type == CORESIGHT_DEV_TYPE_LINKSINK)
+ type = (csdev == coresight_get_sink(path)) ?
+ CORESIGHT_DEV_TYPE_SINK :
+ CORESIGHT_DEV_TYPE_LINK;
+
+ switch (type) {
case CORESIGHT_DEV_TYPE_SINK:
- case CORESIGHT_DEV_TYPE_LINKSINK:
ret = coresight_enable_sink(csdev, mode);
if (ret)
goto err;
@@ -304,6 +316,7 @@ int coresight_enable_path(struct list_head *path, u32 mode)
/* sources are enabled from either sysFS or Perf */
break;
case CORESIGHT_DEV_TYPE_LINK:
+ case CORESIGHT_DEV_TYPE_LINKSINK:
parent = list_prev_entry(nd, link)->csdev;
child = list_next_entry(nd, link)->csdev;
ret = coresight_enable_link(csdev, parent, child);
--
2.1.4