PM: domains: Allow genpd providers to manage OPP tables directly by its FW

In some cases the OPP tables aren't specified in device tree, but rather
encoded in the FW. To allow a genpd provider to specify them dynamically
instead, let's add a new genpd flag, GENPD_FLAG_OPP_TABLE_FW.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Link: https://lore.kernel.org/r/20230825112633.236607-13-ulf.hansson@linaro.orgSigned-off-by: Sudeep Holla <sudeep.holla@arm.com>

drivers/base/power/domain.c

@@ -130,6 +130,7 @@ static const struct genpd_lock_ops genpd_spin_ops = {
 #define genpd_is_active_wakeup(genpd)	(genpd->flags & GENPD_FLAG_ACTIVE_WAKEUP)
 #define genpd_is_cpu_domain(genpd)	(genpd->flags & GENPD_FLAG_CPU_DOMAIN)
 #define genpd_is_rpm_always_on(genpd)	(genpd->flags & GENPD_FLAG_RPM_ALWAYS_ON)
+#define genpd_is_opp_table_fw(genpd)	(genpd->flags & GENPD_FLAG_OPP_TABLE_FW)
 
 static inline bool irq_safe_dev_in_sleep_domain(struct device *dev,
 		const struct generic_pm_domain *genpd)
@@ -2328,7 +2329,7 @@ int of_genpd_add_provider_simple(struct device_node *np,
 	genpd->dev.of_node = np;
 
 	/* Parse genpd OPP table */
-	if (genpd->set_performance_state) {
+	if (!genpd_is_opp_table_fw(genpd) && genpd->set_performance_state) {
 		ret = dev_pm_opp_of_add_table(&genpd->dev);
 		if (ret)
 			return dev_err_probe(&genpd->dev, ret, "Failed to add OPP table\n");
@@ -2343,7 +2344,7 @@ int of_genpd_add_provider_simple(struct device_node *np,
 
 	ret = genpd_add_provider(np, genpd_xlate_simple, genpd);
 	if (ret) {
-		if (genpd->set_performance_state) {
+		if (!genpd_is_opp_table_fw(genpd) && genpd->set_performance_state) {
 			dev_pm_opp_put_opp_table(genpd->opp_table);
 			dev_pm_opp_of_remove_table(&genpd->dev);
 		}
@@ -2387,7 +2388,7 @@ int of_genpd_add_provider_onecell(struct device_node *np,
 		genpd->dev.of_node = np;
 
 		/* Parse genpd OPP table */
-		if (genpd->set_performance_state) {
+		if (!genpd_is_opp_table_fw(genpd) && genpd->set_performance_state) {
 			ret = dev_pm_opp_of_add_table_indexed(&genpd->dev, i);
 			if (ret) {
 				dev_err_probe(&genpd->dev, ret,
@@ -2423,7 +2424,7 @@ int of_genpd_add_provider_onecell(struct device_node *np,
 		genpd->provider = NULL;
 		genpd->has_provider = false;
 
-		if (genpd->set_performance_state) {
+		if (!genpd_is_opp_table_fw(genpd) && genpd->set_performance_state) {
 			dev_pm_opp_put_opp_table(genpd->opp_table);
 			dev_pm_opp_of_remove_table(&genpd->dev);
 		}
@@ -2455,7 +2456,7 @@ void of_genpd_del_provider(struct device_node *np)
 				if (gpd->provider == &np->fwnode) {
 					gpd->has_provider = false;
 
-					if (!gpd->set_performance_state)
+					if (genpd_is_opp_table_fw(gpd) || !gpd->set_performance_state)
 						continue;
 
 					dev_pm_opp_put_opp_table(gpd->opp_table);

include/linux/pm_domain.h

@@ -61,6 +61,10 @@
  * GENPD_FLAG_MIN_RESIDENCY:	Enable the genpd governor to consider its
  *				components' next wakeup when determining the
  *				optimal idle state.
+ *
+ * GENPD_FLAG_OPP_TABLE_FW:	The genpd provider supports performance states,
+ *				but its corresponding OPP tables are not
+ *				described in DT, but are given directly by FW.
  */
 #define GENPD_FLAG_PM_CLK	 (1U << 0)
 #define GENPD_FLAG_IRQ_SAFE	 (1U << 1)
@@ -69,6 +73,7 @@
 #define GENPD_FLAG_CPU_DOMAIN	 (1U << 4)
 #define GENPD_FLAG_RPM_ALWAYS_ON (1U << 5)
 #define GENPD_FLAG_MIN_RESIDENCY (1U << 6)
+#define GENPD_FLAG_OPP_TABLE_FW	 (1U << 7)
 
 enum gpd_status {
 	GENPD_STATE_ON = 0,	/* PM domain is on */