interconnect: qcom: osm-l3: Mark more structures const

Commit Message

Stephen Boyd Sept. 14, 2020, 6:21 p.m. UTC

These structures aren't modified at runtime. Mark them const so they get
moved to read-only memory. We have to cast away const in one place when
we store into the data member of struct icc_node. This is paired with a
re-const of the data member when it is extracted in qcom_icc_set().

Cc: Sibi Sankar <[e-mail]>
Cc: Evan Green <[e-mail]>
Signed-off-by: Stephen Boyd <[e-mail]>
---
 drivers/interconnect/qcom/osm-l3.c | 15 ++++++++-------
 1 file changed, 8 insertions(+), 7 deletions(-)

Comments

Evan Green Sept. 14, 2020, 9:22 p.m. UTC | #1

On Mon, Sep 14, 2020 at 11:21 AM Stephen Boyd <[e-mail]> wrote:
>
> These structures aren't modified at runtime. Mark them const so they get
> moved to read-only memory. We have to cast away const in one place when
> we store into the data member of struct icc_node. This is paired with a
> re-const of the data member when it is extracted in qcom_icc_set().
>
> Cc: Sibi Sankar <[e-mail]>
> Cc: Evan Green <[e-mail]>
> Signed-off-by: Stephen Boyd <[e-mail]>

Reviewed-by: Evan Green <[e-mail]>

Patch

diff --git a/drivers/interconnect/qcom/osm-l3.c b/drivers/interconnect/qcom/osm-l3.c
index 96fb9ff5ff2e..ba2ee6683a82 100644
--- a/drivers/interconnect/qcom/osm-l3.c
+++ b/drivers/interconnect/qcom/osm-l3.c
@@ -57,12 +57,12 @@  struct qcom_icc_node {
 };
 
 struct qcom_icc_desc {
-	struct qcom_icc_node **nodes;
+	const struct qcom_icc_node **nodes;
 	size_t num_nodes;
 };
 
 #define DEFINE_QNODE(_name, _id, _buswidth, ...)			\
-		static struct qcom_icc_node _name = {			\
+	static const struct qcom_icc_node _name = {			\
 		.name = #_name,						\
 		.id = _id,						\
 		.buswidth = _buswidth,					\
@@ -73,7 +73,7 @@  struct qcom_icc_desc {
 DEFINE_QNODE(sdm845_osm_apps_l3, SDM845_MASTER_OSM_L3_APPS, 16, SDM845_SLAVE_OSM_L3);
 DEFINE_QNODE(sdm845_osm_l3, SDM845_SLAVE_OSM_L3, 16);
 
-static struct qcom_icc_node *sdm845_osm_l3_nodes[] = {
+static const struct qcom_icc_node *sdm845_osm_l3_nodes[] = {
 	[MASTER_OSM_L3_APPS] = &sdm845_osm_apps_l3,
 	[SLAVE_OSM_L3] = &sdm845_osm_l3,
 };
@@ -86,7 +86,7 @@  static const struct qcom_icc_desc sdm845_icc_osm_l3 = {
 DEFINE_QNODE(sc7180_osm_apps_l3, SC7180_MASTER_OSM_L3_APPS, 16, SC7180_SLAVE_OSM_L3);
 DEFINE_QNODE(sc7180_osm_l3, SC7180_SLAVE_OSM_L3, 16);
 
-static struct qcom_icc_node *sc7180_osm_l3_nodes[] = {
+static const struct qcom_icc_node *sc7180_osm_l3_nodes[] = {
 	[MASTER_OSM_L3_APPS] = &sc7180_osm_apps_l3,
 	[SLAVE_OSM_L3] = &sc7180_osm_l3,
 };
@@ -100,7 +100,7 @@  static int qcom_icc_set(struct icc_node *src, struct icc_node *dst)
 {
 	struct qcom_osm_l3_icc_provider *qp;
 	struct icc_provider *provider;
-	struct qcom_icc_node *qn;
+	const struct qcom_icc_node *qn;
 	struct icc_node *n;
 	unsigned int index;
 	u32 agg_peak = 0;
@@ -145,7 +145,7 @@  static int qcom_osm_l3_probe(struct platform_device *pdev)
 	const struct qcom_icc_desc *desc;
 	struct icc_onecell_data *data;
 	struct icc_provider *provider;
-	struct qcom_icc_node **qnodes;
+	const struct qcom_icc_node **qnodes;
 	struct icc_node *node;
 	size_t num_nodes;
 	struct clk *clk;
@@ -235,7 +235,8 @@  static int qcom_osm_l3_probe(struct platform_device *pdev)
 		}
 
 		node->name = qnodes[i]->name;
-		node->data = qnodes[i];
+		/* Cast away const and add it back in qcom_icc_set() */
+		node->data = (void *)qnodes[i];
 		icc_node_add(node, provider);
 
 		for (j = 0; j < qnodes[i]->num_links; j++)