[Patch v2 0/2] Add support for AOSS resources that are used to warm up the SoC

[Patch v2 0/2] Add support for AOSS resources that are used to warm up the SoC

[Thara Gopinath]

The Always On Sub System (AOSS) hosts certain resources
that are used to warm up the soc if the temperature falls
below certain threshold. These resources are
added can be considered as thermal warming devices
(opposite of thermal cooling devices).

These resources are controlled via AOSS QMP protocol
In kernel, these devices can be treated the same way as any other
thermal cooling device and hence are registered with the thermal
cooling framework.

To use these resources as warming devices require further tweaks in
the thermal framework which are out of scope of this patch series.

Thara Gopinath (2):
  soc: qcom: Extend AOSS QMP driver to support resources that are used
    to wake up the SoC.
  arm64: dts: qcom: Extend AOSS QMP node

 arch/arm64/boot/dts/qcom/sdm845.dtsi |   8 +++
 drivers/soc/qcom/qcom_aoss.c         | 131 +++++++++++++++++++++++++++++++++++
 2 files changed, 139 insertions(+)

-- 
2.1.4

[Patch v2 1/2] soc: qcom: Extend AOSS QMP driver to support resources that are used to wake up the SoC.

[Thara Gopinath]

The AOSS QMP driver is extended to communicate with the additional
resources. These resources are then registered as cooling devices
with the thermal framework.

Signed-off-by: Thara Gopinath <thara.gopinath@linaro.org>
---
v1->v2:
        Added back name variable in qmp_cooling_device to fix the 
        compilation error.               
        Other minor naming changes as mentioned in review on the list.

 drivers/soc/qcom/qcom_aoss.c | 131 +++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 131 insertions(+)

diff --git a/drivers/soc/qcom/qcom_aoss.c b/drivers/soc/qcom/qcom_aoss.c
index 5f88519..dc6201e 100644
--- a/drivers/soc/qcom/qcom_aoss.c
+++ b/drivers/soc/qcom/qcom_aoss.c
@@ -10,6 +10,8 @@
 #include <linux/module.h>
 #include <linux/platform_device.h>
 #include <linux/pm_domain.h>
+#include <linux/thermal.h>
+#include <linux/slab.h>
 
 #define QMP_DESC_MAGIC			0x0
 #define QMP_DESC_VERSION		0x4
@@ -40,6 +42,17 @@
 /* 64 bytes is enough to store the requests and provides padding to 4 bytes */
 #define QMP_MSG_LEN			64
 
+#define QMP_NUM_COOLING_RESOURCES	2
+
+static bool qmp_cdev_init_state = 1;
+
+struct qmp_cooling_device {
+	struct thermal_cooling_device *cdev;
+	struct qmp *qmp;
+	char *name;
+	bool state;
+};
+
 /**
  * struct qmp - driver state for QMP implementation
  * @msgram: iomem referencing the message RAM used for communication
@@ -69,6 +82,7 @@ struct qmp {
 
 	struct clk_hw qdss_clk;
 	struct genpd_onecell_data pd_data;
+	struct qmp_cooling_device *cooling_devs;
 };
 
 struct qmp_pd {
@@ -385,6 +399,118 @@ static void qmp_pd_remove(struct qmp *qmp)
 		pm_genpd_remove(data->domains[i]);
 }
 
+static int qmp_cdev_get_max_state(struct thermal_cooling_device *cdev,
+				  unsigned long *state)
+{
+	*state = qmp_cdev_init_state;
+	return 0;
+}
+
+static int qmp_cdev_get_cur_state(struct thermal_cooling_device *cdev,
+				  unsigned long *state)
+{
+	struct qmp_cooling_device *qmp_cdev = cdev->devdata;
+
+	*state = qmp_cdev->state;
+	return 0;
+}
+
+static int qmp_cdev_set_cur_state(struct thermal_cooling_device *cdev,
+				  unsigned long state)
+{
+	struct qmp_cooling_device *qmp_cdev = cdev->devdata;
+	char buf[QMP_MSG_LEN] = {};
+	bool cdev_state;
+	int ret;
+
+	/* Normalize state */
+	cdev_state = !!state;
+
+	if (qmp_cdev->state == state)
+		return 0;
+
+	snprintf(buf, sizeof(buf),
+		 "{class: volt_flr, event:zero_temp, res:%s, value:%s}",
+			qmp_cdev->name,
+			cdev_state ? "off" : "on");
+
+	ret = qmp_send(qmp_cdev->qmp, buf, sizeof(buf));
+
+	if (!ret)
+		qmp_cdev->state = cdev_state;
+
+	return ret;
+}
+
+static struct thermal_cooling_device_ops qmp_cooling_device_ops = {
+	.get_max_state = qmp_cdev_get_max_state,
+	.get_cur_state = qmp_cdev_get_cur_state,
+	.set_cur_state = qmp_cdev_set_cur_state,
+};
+
+static int qmp_cooling_device_add(struct qmp *qmp,
+				  struct qmp_cooling_device *qmp_cdev,
+				  struct device_node *node)
+{
+	char *cdev_name = (char *)node->name;
+
+	qmp_cdev->qmp = qmp;
+	qmp_cdev->state = qmp_cdev_init_state;
+	qmp_cdev->name = cdev_name;
+	qmp_cdev->cdev = devm_thermal_of_cooling_device_register
+				(qmp->dev, node,
+				cdev_name,
+				qmp_cdev, &qmp_cooling_device_ops);
+
+	if (IS_ERR(qmp_cdev->cdev))
+		dev_err(qmp->dev, "unable to register %s cooling device\n",
+			cdev_name);
+
+	return PTR_ERR_OR_ZERO(qmp_cdev->cdev);
+}
+
+static int qmp_cooling_devices_register(struct qmp *qmp)
+{
+	struct device_node *np, *child;
+	int count = QMP_NUM_COOLING_RESOURCES;
+	int ret;
+
+	np = qmp->dev->of_node;
+
+	qmp->cooling_devs = devm_kcalloc(qmp->dev, count,
+					 sizeof(*qmp->cooling_devs),
+					 GFP_KERNEL);
+
+	if (!qmp->cooling_devs)
+		return -ENOMEM;
+
+	for_each_available_child_of_node(np, child) {
+		if (!of_find_property(child, "#cooling-cells", NULL))
+			continue;
+		ret = qmp_cooling_device_add(qmp, &qmp->cooling_devs[count++],
+					     child);
+		if (ret)
+			goto uroll;
+	}
+
+	return 0;
+
+uroll:
+	while (--count >= 0)
+		thermal_cooling_device_unregister
+			(qmp->cooling_devs[count].cdev);
+
+	return ret;
+}
+
+static void qmp_cooling_devices_remove(struct qmp *qmp)
+{
+	int i;
+
+	for (i = 0; i < QMP_NUM_COOLING_RESOURCES; i++)
+		thermal_cooling_device_unregister(qmp->cooling_devs[i].cdev);
+}
+
 static int qmp_probe(struct platform_device *pdev)
 {
 	struct resource *res;
@@ -433,6 +559,10 @@ static int qmp_probe(struct platform_device *pdev)
 	if (ret)
 		goto err_remove_qdss_clk;
 
+	ret = qmp_cooling_devices_register(qmp);
+	if (ret)
+		dev_err(&pdev->dev, "failed to register aoss cooling devices\n");
+
 	platform_set_drvdata(pdev, qmp);
 
 	return 0;
@@ -453,6 +583,7 @@ static int qmp_remove(struct platform_device *pdev)
 
 	qmp_qdss_clk_remove(qmp);
 	qmp_pd_remove(qmp);
+	qmp_cooling_devices_remove(qmp);
 
 	qmp_close(qmp);
 	mbox_free_channel(qmp->mbox_chan);
-- 
2.1.4

[Patch v2 2/2] arm64: dts: qcom: Extend AOSS QMP node

[Thara Gopinath]

AOSS hosts resources that can be used to warm up the SoC.
Add nodes for these resources.

Signed-off-by: Thara Gopinath <thara.gopinath@linaro.org>
---
 arch/arm64/boot/dts/qcom/sdm845.dtsi | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/arch/arm64/boot/dts/qcom/sdm845.dtsi b/arch/arm64/boot/dts/qcom/sdm845.dtsi
index 4babff5..d0c0d4f 100644
--- a/arch/arm64/boot/dts/qcom/sdm845.dtsi
+++ b/arch/arm64/boot/dts/qcom/sdm845.dtsi
@@ -2411,6 +2411,14 @@
 
 			#clock-cells = <0>;
 			#power-domain-cells = <1>;
+
+			cx_cdev: cx {
+				#cooling-cells = <2>;
+			};
+
+			ebi_cdev: ebi {
+				#cooling-cells = <2>;
+			};
 		};
 
 		spmi_bus: spmi@c440000 {
-- 
2.1.4