OPP: Allow multiple clocks for a device

This patch adds support to allow multiple clocks for a device.

The design is pretty much similar to how this is done for regulators,
and platforms can supply their own version of the config_clks() callback
if they have multiple clocks for their device. The core manages the
calls via opp_table->config_clks() eventually.

We have kept both "clk" and "clks" fields in the OPP table structure and
the reason is provided as a comment in _opp_set_clknames(). The same
isn't done for "rates" though and we use rates[0] at most of the places
now.

Co-developed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Tested-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
Tested-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

1 files changed, 52 insertions, 14 deletions

diff --git a/drivers/opp/of.c b/drivers/opp/of.c
index bb49057cb1fc..7607e112df3f 100644
--- a/drivers/opp/of.c
+++ b/drivers/opp/of.c
@@ -767,6 +767,50 @@ void dev_pm_opp_of_remove_table(struct device *dev)
 }
 EXPORT_SYMBOL_GPL(dev_pm_opp_of_remove_table);
 
+static int _read_rate(struct dev_pm_opp *new_opp, struct opp_table *opp_table,
+		      struct device_node *np)
+{
+	struct property *prop;
+	int i, count, ret;
+	u64 *rates;
+
+	prop = of_find_property(np, "opp-hz", NULL);
+	if (!prop)
+		return -ENODEV;
+
+	count = prop->length / sizeof(u64);
+	if (opp_table->clk_count != count) {
+		pr_err("%s: Count mismatch between opp-hz and clk_count (%d %d)\n",
+		       __func__, count, opp_table->clk_count);
+		return -EINVAL;
+	}
+
+	rates = kmalloc_array(count, sizeof(*rates), GFP_KERNEL);
+	if (!rates)
+		return -ENOMEM;
+
+	ret = of_property_read_u64_array(np, "opp-hz", rates, count);
+	if (ret) {
+		pr_err("%s: Error parsing opp-hz: %d\n", __func__, ret);
+	} 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.
+		 */
+		for (i = 0; i < count; i++) {
+			new_opp->rates[i] = (unsigned long)rates[i];
+
+			/* This will happen for frequencies > 4.29 GHz */
+			WARN_ON(new_opp->rates[i] != rates[i]);
+		}
+	}
+
+	kfree(rates);
+
+	return ret;
+}
+
 static int _read_bw(struct dev_pm_opp *new_opp, struct opp_table *opp_table,
 		    struct device_node *np, bool peak)
 {
@@ -812,19 +856,13 @@ static int _read_opp_key(struct dev_pm_opp *new_opp,
 			 struct opp_table *opp_table, struct device_node *np)
 {
 	bool found = false;
-	u64 rate;
 	int ret;
 
-	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;
+	ret = _read_rate(new_opp, opp_table, np);
+	if (!ret)
 		found = true;
-	}
+	else if (ret != -ENODEV)
+		return ret;
 
 	/*
 	 * Bandwidth consists of peak and average (optional) values:
@@ -893,8 +931,8 @@ static struct dev_pm_opp *_opp_add_static_v2(struct opp_table *opp_table,
 
 	/* 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: %lu\n",
-			new_opp->rate);
+		dev_dbg(dev, "OPP not supported by hardware: %s\n",
+			of_node_full_name(np));
 		goto free_opp;
 	}
 
@@ -930,7 +968,7 @@ 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/bw/level as suspend OPP */
-			if (_opp_compare_key(new_opp, opp_table->suspend_opp) == 1) {
+			if (_opp_compare_key(opp_table, new_opp, opp_table->suspend_opp) == 1) {
 				opp_table->suspend_opp->suspend = false;
 				new_opp->suspend = true;
 				opp_table->suspend_opp = new_opp;
@@ -945,7 +983,7 @@ static struct dev_pm_opp *_opp_add_static_v2(struct opp_table *opp_table,
 		opp_table->clock_latency_ns_max = new_opp->clock_latency_ns;
 
 	pr_debug("%s: turbo:%d rate:%lu uv:%lu uvmin:%lu uvmax:%lu latency:%lu level:%u\n",
-		 __func__, new_opp->turbo, new_opp->rate,
+		 __func__, new_opp->turbo, new_opp->rates[0],
 		 new_opp->supplies[0].u_volt, new_opp->supplies[0].u_volt_min,
 		 new_opp->supplies[0].u_volt_max, new_opp->clock_latency_ns,
 		 new_opp->level);