disp: msm: add support to request mdp core clk through mmrm

For Waipio onwards, mdp core clock rate needs to be requested
through the mmrm driver, which will make sure the requested
rate can be sustained by the its power rail, which is shared
by multiple clients.
Current change adds the support to request the mdp core clk rate
through mmrm driver as well as returns the corresponding failures
to user space during when a rate cannot be supported by the
system.

Change-Id: Icc0e8ab5b71e8c99baf7913bdbd96d9504cc11ae
Signed-off-by: Ingrid Gallardo <ingridg@codeaurora.org>

msm/sde_power_handle.h

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: GPL-2.0-only */
 /*
- * Copyright (c) 2016-2020, The Linux Foundation. All rights reserved.
+ * Copyright (c) 2016-2021, The Linux Foundation. All rights reserved.
  */
 
 #ifndef _SDE_POWER_HANDLE_H_
@@ -31,6 +31,10 @@
 
 /* event will be triggered after power handler enable */
 #define SDE_POWER_EVENT_POST_ENABLE	0x8
+
+/* event will be triggered during MMRM callback */
+#define SDE_POWER_EVENT_MMRM_CALLBACK	0x10
+
 #define DATA_BUS_PATH_MAX	0x2
 
 /*
@@ -153,6 +157,7 @@ struct sde_power_event {
  * @event_list: current power handle event list
  * @rsc_client: sde rsc client pointer
  * @rsc_client_init: boolean to control rsc client create
+ * @mmrm_enable: boolean to indicate if mmrm is enabled
  */
 struct sde_power_handle {
 	struct dss_module_power mp;
@@ -165,6 +170,7 @@ struct sde_power_handle {
 	u32 last_event_handled;
 	struct sde_rsc_client *rsc_client;
 	bool rsc_client_init;
+	bool mmrm_enable;
 };
 
 /**
@@ -223,11 +229,45 @@ int sde_power_data_bus_state_update(struct sde_power_handle *phandle,
  * @pdata:  power handle containing the resources
  * @clock_name: clock name which needs rate update.
  * @rate:       Requested rate.
+ * @flags:      Flags to be set for this clk
  *
  * Return: error code.
  */
 int sde_power_clk_set_rate(struct sde_power_handle *pdata, char *clock_name,
-	u64 rate);
+	u64 rate, u32 flags);
+
+/**
+ * sde_power_mmrm_set_clk_limit() - sets a limit for mdp core clk
+ * @clk: pointer to the mdp core clk
+ * @phandle: power handle containing the resources
+ * @requested_clk: limit requested for the core clk
+ *
+ * This function must be called in a thread different than the
+ * commit-thread, otherwise it will always fail, since this function
+ * sends a notification to user-space to reduce the clk, and then it
+ * waits for the next commit after this call to reduce the clk rate.
+ * Hence, if the commit-thread is blocked (by this function waiting)
+ * or if user-space does not send another commit to reduce the clk,
+ * this function will timeout after some time and fail.
+ *
+ * Return: 0 upon succeeding setting the clk to a value lower or
+ *  equal than the 'requested_clk', otherwise it returns an
+ *  error code.
+ */
+int sde_power_mmrm_set_clk_limit(struct dss_clk *clk,
+	struct sde_power_handle *phandle, unsigned long requested_clk);
+
+/**
+ * sde_power_mmrm_get_requested_clk() - get clk rate requested by mmrm
+ * @pdata:  power handle containing the resources
+ * @clock_name: clock name to get the rate requested by mmrm driver
+ *   to decrease
+ *
+ * Return: clock rate requested by mmrm driver, if 0,
+ *   then no active request by mmrm driver
+ */
+u64 sde_power_mmrm_get_requested_clk(struct sde_power_handle *pdata,
+	char *clock_name);
 
 /**
  * sde_power_clk_get_rate() - get the clock rate