[PATCH v5 3/3] interconnect: Allow inter-provider pairs to be configured

From: Sylwester Nawrocki
Date: Thu May 21 2020 - 08:29:03 EST


From: Artur ÅwigoÅ <a.swigon@xxxxxxxxxxx>

This patch adds support for a new boolean 'inter_set' field in struct
icc_provider. Setting it to 'true' enables calling '->set' for
inter-provider node pairs. All existing users of the interconnect
framework allocate this structure with kzalloc, and are therefore
unaffected by this change.

This makes it easier for hierarchies like exynos-bus, where every bus
is probed separately and registers a separate interconnect provider, to
model constraints between buses.

Signed-off-by: Artur ÅwigoÅ <a.swigon@xxxxxxxxxxx>
Signed-off-by: Sylwester Nawrocki <s.nawrocki@xxxxxxxxxxx>
---
drivers/interconnect/core.c | 11 +++++------
include/linux/interconnect-provider.h | 2 ++
2 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/drivers/interconnect/core.c b/drivers/interconnect/core.c
index 6a342ef..b549249 100644
--- a/drivers/interconnect/core.c
+++ b/drivers/interconnect/core.c
@@ -263,23 +263,22 @@ static int aggregate_requests(struct icc_node *node)
static int apply_constraints(struct icc_path *path)
{
struct icc_node *next, *prev = NULL;
+ struct icc_provider *p;
int ret = -EINVAL;
int i;

for (i = 0; i < path->num_nodes; i++) {
next = path->reqs[i].node;
+ p = next->provider;

- /*
- * Both endpoints should be valid master-slave pairs of the
- * same interconnect provider that will be configured.
- */
- if (!prev || next->provider != prev->provider) {
+ /* both endpoints should be valid master-slave pairs */
+ if (!prev || (p != prev->provider && !p->inter_set)) {
prev = next;
continue;
}

/* set the constraints */
- ret = next->provider->set(prev, next);
+ ret = p->set(prev, next);
if (ret)
goto out;

diff --git a/include/linux/interconnect-provider.h b/include/linux/interconnect-provider.h
index c92be2a..38701925 100644
--- a/include/linux/interconnect-provider.h
+++ b/include/linux/interconnect-provider.h
@@ -41,6 +41,7 @@ struct icc_node *of_icc_xlate_onecell(struct of_phandle_args *spec,
* @xlate: provider-specific callback for mapping nodes from phandle arguments
* @dev: the device this interconnect provider belongs to
* @users: count of active users
+ * @inter_set: whether inter-provider pairs will be configured with @set
* @data: pointer to private data
*/
struct icc_provider {
@@ -53,6 +54,7 @@ struct icc_provider {
struct icc_node* (*xlate)(struct of_phandle_args *spec, void *data);
struct device *dev;
int users;
+ bool inter_set;
void *data;
};

--
2.7.4