Re: [PATCH v6 2/3] OPP: Add support for bandwidth OPP tables
From: Sibi Sankar
Date: Tue Jan 07 2020 - 14:28:35 EST
Hey Saravana,
Spent some time testing this series while
trying out dcvs on SDM845/SC7180. Apart from
the few minor issues it works quite well!
On 2019-12-07 05:54, Saravana Kannan wrote:
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 <saravanak@xxxxxxxxxx>
---
drivers/opp/core.c | 15 +++++++++--
drivers/opp/of.c | 63 ++++++++++++++++++++++++++++++++--------------
drivers/opp/opp.h | 5 ++++
3 files changed, 62 insertions(+), 21 deletions(-)
diff --git a/drivers/opp/core.c b/drivers/opp/core.c
index be7a7d332332..c79bbfac7289 100644
--- a/drivers/opp/core.c
+++ b/drivers/opp/core.c
@@ -1282,11 +1282,21 @@ static bool
_opp_supported_by_regulators(struct dev_pm_opp *opp,
return true;
}
+int opp_compare_key(struct dev_pm_opp *opp1, struct dev_pm_opp *opp2)
+{
+ if (opp1->rate != opp2->rate)
+ return opp1->rate < opp2->rate ? -1 : 1;
+ if (opp1->peak_bw != opp2->peak_bw)
+ return opp1->peak_bw < opp2->peak_bw ? -1 : 1;
+ return 0;
+}
+
static int _opp_is_duplicate(struct device *dev, struct dev_pm_opp
*new_opp,
struct opp_table *opp_table,
struct list_head **head)
{
struct dev_pm_opp *opp;
+ int opp_cmp;
/*
* Insert new OPP in order of increasing frequency and discard if
@@ -1297,12 +1307,13 @@ static int _opp_is_duplicate(struct device
*dev, struct dev_pm_opp *new_opp,
* loop.
*/
list_for_each_entry(opp, &opp_table->opp_list, node) {
- if (new_opp->rate > opp->rate) {
+ opp_cmp = opp_compare_key(new_opp, opp);
+ if (opp_cmp > 0) {
*head = &opp->node;
continue;
}
- if (new_opp->rate < opp->rate)
+ if (opp_cmp < 0)
return 0;
/* Duplicate OPPs */
diff --git a/drivers/opp/of.c b/drivers/opp/of.c
index 1cbb58240b80..b565da5a2b1f 100644
--- a/drivers/opp/of.c
+++ b/drivers/opp/of.c
@@ -521,6 +521,44 @@ 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,
+ bool *rate_not_available)
+{
+ 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;
+ goto out;
+ }
+
+ ret = of_property_read_u32(np, "opp-peak-kBps", &bw);
+ if (!ret) {
+ new_opp->peak_bw = bw;
+
+ if (!of_property_read_u32(np, "opp-avg-kBps", &bw))
+ new_opp->avg_bw = bw;
+ }
+
+out:
+ *rate_not_available = !!ret;
+ /*
+ * If ret is 0 at this point, we have already found a key. If we
+ * haven't found a key yet, then ret already has an error value. In
+ * either case, we don't need to update ret.
+ */
+ of_property_read_u32(np, "opp-level", &new_opp->level);
+
+ return ret;
+}
+
/**
* _opp_add_static_v2() - Allocate static OPPs (As per 'v2' DT
bindings)
* @opp_table: OPP table
@@ -558,26 +596,12 @@ 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);
- 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__);
- goto free_opp;
- }
-
- rate_not_available = true;
- } else {
- /*
- * 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;
+ ret = _read_opp_key(new_opp, np, &rate_not_available);
+ if (ret) {
if (!opp_table->is_genpd) {
_read_opp_key returns an error for genpd
opps so please check if it is a genpd
opp_table before erroring out here.
+ dev_err(dev, "%s: opp key field not found\n", __func__);
+ goto free_opp;
}
- of_property_read_u32(np, "opp-level", &new_opp->level);
-
/* Check if the OPP supports hardware's hierarchy of versions or not
*/
if (!_opp_is_supported(dev, opp_table, np)) {
dev_dbg(dev, "OPP not supported by hardware: %llu\n", rate);
@@ -616,7 +640,8 @@ static struct dev_pm_opp
*_opp_add_static_v2(struct opp_table *opp_table,
if (of_property_read_bool(np, "opp-suspend")) {
if (opp_table->suspend_opp) {
/* Pick the OPP with higher rate as suspend OPP */
- if (new_opp->rate > opp_table->suspend_opp->rate) {
+ if (opp_compare_key(new_opp,
+ opp_table->suspend_opp) > 1) {
shouldn't the condition be > 0?
opp_table->suspend_opp->suspend = false;
new_opp->suspend = true;
opp_table->suspend_opp = new_opp;
diff --git a/drivers/opp/opp.h b/drivers/opp/opp.h
index 01a500e2c40a..0def3154d07b 100644
--- a/drivers/opp/opp.h
+++ b/drivers/opp/opp.h
@@ -57,6 +57,8 @@ extern struct list_head opp_tables;
* @suspend: true if suspend OPP
* @pstate: Device's power domain's performance state.
* @rate: Frequency in hertz
+ * @peak_bw: 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
@@ -78,6 +80,8 @@ struct dev_pm_opp {
bool suspend;
unsigned int pstate;
unsigned long rate;
+ unsigned int peak_bw;
+ unsigned int avg_bw;
unsigned int level;
struct dev_pm_opp_supply *supplies;
@@ -213,6 +217,7 @@ struct opp_device *_add_opp_dev(const struct
device *dev, struct opp_table *opp_
void _dev_pm_opp_find_and_remove_table(struct device *dev);
struct dev_pm_opp *_opp_allocate(struct opp_table *opp_table);
void _opp_free(struct dev_pm_opp *opp);
+int opp_compare_key(struct dev_pm_opp *opp1, struct dev_pm_opp *opp2);
int _opp_add(struct device *dev, struct dev_pm_opp *new_opp, struct
opp_table *opp_table, bool rate_not_available);
int _opp_add_v1(struct opp_table *opp_table, struct device *dev,
unsigned long freq, long u_volt, bool dynamic);
void _dev_pm_opp_cpumask_remove_table(const struct cpumask *cpumask,
int last_cpu);
--
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