coresight: configuring ETF in FIFO mode when acting as link

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@linaro.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 28 insertions, 4 deletions

diff --git a/drivers/hwtracing/coresight/coresight.c b/drivers/hwtracing/coresight/coresight.c
index 0995df8f85bc..5443d03a1eec 100644
--- a/drivers/hwtracing/coresight/coresight.c
+++ b/drivers/hwtracing/coresight/coresight.c
@@ -265,15 +265,27 @@ static void coresight_disable_source(struct coresight_device *csdev)
 
 void coresight_disable_path(struct list_head *path)
 {
+        u32 type;
         struct coresight_node *nd;
         struct coresight_device *csdev, *parent, *child;
 
         list_for_each_entry(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:
                         coresight_disable_sink(csdev);
                         break;
                 case CORESIGHT_DEV_TYPE_SOURCE:
@@ -294,15 +306,27 @@ 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;
+
+                /*
+                 * 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 (csdev->type) {
+                switch (type) {
                 case CORESIGHT_DEV_TYPE_SINK:
-                case CORESIGHT_DEV_TYPE_LINKSINK:
                         ret = coresight_enable_sink(csdev, mode);
                         if (ret)
                                 goto err;