Not all devices quantify their performance points in terms of frequency.
Devices like interconnects quantify their performance points in terms of
bandwidth. We need a way to represent these bandwidth levels in OPP. So,
add support for parsing bandwidth OPPs from DT.

Signed-off-by: Saravana Kannan <sarava...@google.com>
---
 drivers/opp/of.c  | 34 ++++++++++++++++++++++++++++++++--
 drivers/opp/opp.h |  4 +++-
 2 files changed, 35 insertions(+), 3 deletions(-)

diff --git a/drivers/opp/of.c b/drivers/opp/of.c
index c10c782d15aa..54fa70ed2adc 100644
--- a/drivers/opp/of.c
+++ b/drivers/opp/of.c
@@ -552,6 +552,35 @@ void dev_pm_opp_of_remove_table(struct device *dev)
 }
 EXPORT_SYMBOL_GPL(dev_pm_opp_of_remove_table);
 
+static int _read_opp_key(struct dev_pm_opp *new_opp, struct device_node *np)
+{
+       int ret;
+       u64 rate;
+       u32 bw;
+
+       ret = of_property_read_u64(np, "opp-hz", &rate);
+       if (!ret) {
+               /*
+                * Rate is defined as an unsigned long in clk API, and so
+                * casting explicitly to its type. Must be fixed once rate is 64
+                * bit guaranteed in clk API.
+                */
+               new_opp->rate = (unsigned long)rate;
+               return 0;
+       }
+
+       ret = of_property_read_u32(np, "opp-peak-KBps", &bw);
+       if (ret)
+               return ret;
+       new_opp->rate = (unsigned long) &bw;
+
+       ret = of_property_read_u32(np, "opp-avg-KBps", &bw);
+       if (!ret)
+               new_opp->avg_bw = (unsigned long) &bw;
+
+       return 0;
+}
+
 /**
  * _opp_add_static_v2() - Allocate static OPPs (As per 'v2' DT bindings)
  * @opp_table: OPP table
@@ -589,11 +618,12 @@ static struct dev_pm_opp *_opp_add_static_v2(struct 
opp_table *opp_table,
        if (!new_opp)
                return ERR_PTR(-ENOMEM);
 
-       ret = of_property_read_u64(np, "opp-hz", &rate);
+       ret = _read_opp_key(new_opp, np);
        if (ret < 0) {
                /* "opp-hz" is optional for devices like power domains. */
                if (!opp_table->is_genpd) {
-                       dev_err(dev, "%s: opp-hz not found\n", __func__);
+                       dev_err(dev, "%s: opp-hz or opp-peak-bw not found\n",
+                               __func__);
                        goto free_opp;
                }
 
diff --git a/drivers/opp/opp.h b/drivers/opp/opp.h
index 569b3525aa67..ead2cdafe957 100644
--- a/drivers/opp/opp.h
+++ b/drivers/opp/opp.h
@@ -59,7 +59,8 @@ extern struct list_head opp_tables;
  * @turbo:     true if turbo (boost) OPP
  * @suspend:   true if suspend OPP
  * @pstate: Device's power domain's performance state.
- * @rate:      Frequency in hertz
+ * @rate:      Frequency in hertz OR Peak bandwidth in kilobytes per second
+ * @avg_bw:    Average bandwidth in kilobytes per second
  * @level:     Performance level
  * @supplies:  Power supplies voltage/current values
  * @clock_latency_ns: Latency (in nanoseconds) of switching to this OPP's
@@ -81,6 +82,7 @@ struct dev_pm_opp {
        bool suspend;
        unsigned int pstate;
        unsigned long rate;
+       unsigned long avg_bw;
        unsigned int level;
 
        struct dev_pm_opp_supply *supplies;
-- 
2.22.0.rc2.383.gf4fbbf30c2-goog

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