[PATCH v2 2/5] clk: scmi: Add support for state control restricted clocks

Cristian Marussi
2024-03-25T21:00:53Z

Some exposed SCMI Clocks could be marked as non-supporting state changes.
Configure a clk_ops descriptor which does not provide the state change
callbacks for such clocks when registering with CLK framework.

CC: Michael Turquette <mturquette@baylibre.com>
CC: Stephen Boyd <sboyd@kernel.org>
CC: linux-clk@vger.kernel.org
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
---
drivers/clk/clk-scmi.c | 22 +++++++++++++++-------
1 file changed, 15 insertions(+), 7 deletions(-)

diff --git a/drivers/clk/clk-scmi.c b/drivers/clk/clk-scmi.c
index d5d369b052bd..fc9603988d91 100644
--- a/drivers/clk/clk-scmi.c
+++ b/drivers/clk/clk-scmi.c
@@ -18,6 +18,7 @@

enum scmi_clk_feats {
SCMI_CLK_ATOMIC_SUPPORTED,
+ SCMI_CLK_STATE_CTRL_FORBIDDEN,
SCMI_CLK_MAX_FEATS
};

@@ -230,15 +231,19 @@ scmi_clk_ops_alloc(struct device *dev, unsigned long feats_key)
* only the prepare/unprepare API, as allowed by the clock framework
* when atomic calls are not available.
*/
- if (feats_key & BIT(SCMI_CLK_ATOMIC_SUPPORTED)) {
- ops->enable = scmi_clk_atomic_enable;
- ops->disable = scmi_clk_atomic_disable;
- ops->is_enabled = scmi_clk_atomic_is_enabled;
- } else {
- ops->prepare = scmi_clk_enable;
- ops->unprepare = scmi_clk_disable;
+ if (!(feats_key & BIT(SCMI_CLK_STATE_CTRL_FORBIDDEN))) {
+ if (feats_key & BIT(SCMI_CLK_ATOMIC_SUPPORTED)) {
+ ops->enable = scmi_clk_atomic_enable;
+ ops->disable = scmi_clk_atomic_disable;
+ } else {
+ ops->prepare = scmi_clk_enable;
+ ops->unprepare = scmi_clk_disable;
+ }
}

+ if (feats_key & BIT(SCMI_CLK_ATOMIC_SUPPORTED))
+ ops->is_enabled = scmi_clk_atomic_is_enabled;
+
/* Rate ops */
ops->recalc_rate = scmi_clk_recalc_rate;
ops->round_rate = scmi_clk_round_rate;
@@ -288,6 +293,9 @@ scmi_clk_ops_select(struct scmi_clk *sclk, bool atomic_capable,
if (atomic_capable && ci->enable_latency <= atomic_threshold)
feats_key |= BIT(SCMI_CLK_ATOMIC_SUPPORTED);

+ if (ci->state_ctrl_forbidden)
+ feats_key |= BIT(SCMI_CLK_STATE_CTRL_FORBIDDEN);
+
/* Lookup previously allocated ops */
ops = clk_ops_db[feats_key];
if (!ops) {
--
2.44.0