diff mbox

[v4,4/7] interconnect: qcom: Add RPM communication

Message ID 20180309210958.16672-5-georgi.djakov@linaro.org (mailing list archive)
State New, archived
Headers show

Commit Message

Georgi Djakov March 9, 2018, 9:09 p.m. UTC 
On some Qualcomm SoCs, there is a remote processor, which controls some of
the Network-On-Chip interconnect resources. Other CPUs express their needs
by communicating with this processor. Add a driver to handle comminication
with this remote processor.

Signed-off-by: Georgi Djakov <georgi.djakov@linaro.org>
---
 .../devicetree/bindings/interconnect/qcom-smd.txt  | 31 ++++++++
 drivers/interconnect/qcom/Makefile                 |  1 +
 drivers/interconnect/qcom/smd-rpm.c                | 90 ++++++++++++++++++++++
 drivers/interconnect/qcom/smd-rpm.h                | 15 ++++
 4 files changed, 137 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/interconnect/qcom-smd.txt
 create mode 100644 drivers/interconnect/qcom/Makefile
 create mode 100644 drivers/interconnect/qcom/smd-rpm.c
 create mode 100644 drivers/interconnect/qcom/smd-rpm.h

Comments

Evan Green May 11, 2018, 9:30 p.m. UTC | #1 
On Fri, Mar 9, 2018 at 1:11 PM Georgi Djakov <georgi.djakov@linaro.org>
wrote:

> On some Qualcomm SoCs, there is a remote processor, which controls some of
> the Network-On-Chip interconnect resources. Other CPUs express their needs
> by communicating with this processor. Add a driver to handle comminication
> with this remote processor.

> Signed-off-by: Georgi Djakov <georgi.djakov@linaro.org>
> ---
>   .../devicetree/bindings/interconnect/qcom-smd.txt  | 31 ++++++++
>   drivers/interconnect/qcom/Makefile                 |  1 +
>   drivers/interconnect/qcom/smd-rpm.c                | 90
++++++++++++++++++++++
>   drivers/interconnect/qcom/smd-rpm.h                | 15 ++++
>   4 files changed, 137 insertions(+)
>   create mode 100644
Documentation/devicetree/bindings/interconnect/qcom-smd.txt
>   create mode 100644 drivers/interconnect/qcom/Makefile
>   create mode 100644 drivers/interconnect/qcom/smd-rpm.c
>   create mode 100644 drivers/interconnect/qcom/smd-rpm.h

> diff --git a/Documentation/devicetree/bindings/interconnect/qcom-smd.txt
b/Documentation/devicetree/bindings/interconnect/qcom-smd.txt
> new file mode 100644
> index 000000000000..14e83ed7019b
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/interconnect/qcom-smd.txt
> @@ -0,0 +1,31 @@
> +Qualcomm SMD-RPM interconnect driver binding
> +------------------------------------------------
> +The RPM is a dedicated hardware engine for managing the shared
> +SoC resources in order to keep the lowest power profile. It
> +communicates with other hardware subsystems via shared memory
> +and accepts requests for various resources.

You never say what RPM or SMD stands for. RPM is Resource Power Manager,
right? But I'm not in the know about SMD. Can you define these somewhere?

-Evan
Georgi Djakov June 6, 2018, 3 p.m. UTC | #2 
Hi Evan,

On 12.05.18 г. 0:30, Evan Green wrote:
> On Fri, Mar 9, 2018 at 1:11 PM Georgi Djakov <georgi.djakov@linaro.org>
> wrote:
> 
>> On some Qualcomm SoCs, there is a remote processor, which controls some of
>> the Network-On-Chip interconnect resources. Other CPUs express their needs
>> by communicating with this processor. Add a driver to handle comminication
>> with this remote processor.
> 
>> Signed-off-by: Georgi Djakov <georgi.djakov@linaro.org>
>> ---
>>   .../devicetree/bindings/interconnect/qcom-smd.txt  | 31 ++++++++
>>   drivers/interconnect/qcom/Makefile                 |  1 +
>>   drivers/interconnect/qcom/smd-rpm.c                | 90
> ++++++++++++++++++++++
>>   drivers/interconnect/qcom/smd-rpm.h                | 15 ++++
>>   4 files changed, 137 insertions(+)
>>   create mode 100644
> Documentation/devicetree/bindings/interconnect/qcom-smd.txt
>>   create mode 100644 drivers/interconnect/qcom/Makefile
>>   create mode 100644 drivers/interconnect/qcom/smd-rpm.c
>>   create mode 100644 drivers/interconnect/qcom/smd-rpm.h
> 
>> diff --git a/Documentation/devicetree/bindings/interconnect/qcom-smd.txt
> b/Documentation/devicetree/bindings/interconnect/qcom-smd.txt
>> new file mode 100644
>> index 000000000000..14e83ed7019b
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/interconnect/qcom-smd.txt
>> @@ -0,0 +1,31 @@
>> +Qualcomm SMD-RPM interconnect driver binding
>> +------------------------------------------------
>> +The RPM is a dedicated hardware engine for managing the shared
>> +SoC resources in order to keep the lowest power profile. It
>> +communicates with other hardware subsystems via shared memory
>> +and accepts requests for various resources.
> 
> You never say what RPM or SMD stands for. RPM is Resource Power Manager,
> right? But I'm not in the know about SMD. Can you define these somewhere?
> 

Sure, it's the Shared Memory Driver back-end used for communicating with
RPM. Now added this explanation into the docs.

Thanks,
Georgi
diff mbox

Patch

diff --git a/Documentation/devicetree/bindings/interconnect/qcom-smd.txt b/Documentation/devicetree/bindings/interconnect/qcom-smd.txt
new file mode 100644
index 000000000000..14e83ed7019b
--- /dev/null
+++ b/Documentation/devicetree/bindings/interconnect/qcom-smd.txt
@@ -0,0 +1,31 @@ 
+Qualcomm SMD-RPM interconnect driver binding
+------------------------------------------------
+The RPM is a dedicated hardware engine for managing the shared
+SoC resources in order to keep the lowest power profile. It
+communicates with other hardware subsystems via shared memory
+and accepts requests for various resources.
+
+Required properties :
+- compatible : shall contain only one of the following:
+			"qcom,interconnect-smd-rpm"
+
+Example:
+	smd {
+		compatible = "qcom,smd";
+
+		rpm {
+			interrupts = <0 168 1>;
+			qcom,ipc = <&apcs 8 0>;
+			qcom,smd-edge = <15>;
+
+			rpm_requests {
+				compatible = "qcom,rpm-msm8916";
+				qcom,smd-channels = "rpm_requests";
+
+				interconnect-smd-rpm {
+					compatible = "qcom,interconnect-smd-rpm";
+				};
+
+			};
+		};
+	};
diff --git a/drivers/interconnect/qcom/Makefile b/drivers/interconnect/qcom/Makefile
new file mode 100644
index 000000000000..095bdef1ee6e
--- /dev/null
+++ b/drivers/interconnect/qcom/Makefile
@@ -0,0 +1 @@ 
+obj-y += smd-rpm.o
diff --git a/drivers/interconnect/qcom/smd-rpm.c b/drivers/interconnect/qcom/smd-rpm.c
new file mode 100644
index 000000000000..0cf772f51642
--- /dev/null
+++ b/drivers/interconnect/qcom/smd-rpm.c
@@ -0,0 +1,90 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * RPM over SMD communication wrapper for interconects
+ *
+ * Copyright (C) 2018 Linaro Ltd
+ * Author: Georgi Djakov <georgi.djakov@linaro.org>
+ */
+
+#include <linux/interconnect-provider.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/soc/qcom/smd-rpm.h>
+#include "smd-rpm.h"
+
+#define	RPM_KEY_BW	0x00007762
+
+static struct qcom_icc_rpm {
+	struct qcom_smd_rpm *rpm;
+} icc_rpm_smd;
+
+struct icc_rpm_smd_req {
+	__le32 key;
+	__le32 nbytes;
+	__le32 value;
+};
+
+bool qcom_icc_rpm_smd_available(void)
+{
+	if (!icc_rpm_smd.rpm)
+		return false;
+
+	return true;
+}
+
+int qcom_icc_rpm_smd_send(int ctx, int rsc_type, int id, u32 val)
+{
+	struct icc_rpm_smd_req req = {
+		.key = cpu_to_le32(RPM_KEY_BW),
+		.nbytes = cpu_to_le32(sizeof(u32)),
+		.value = cpu_to_le32(val),
+	};
+
+	return qcom_rpm_smd_write(icc_rpm_smd.rpm, ctx, rsc_type, id, &req,
+				  sizeof(req));
+}
+EXPORT_SYMBOL(qcom_icc_rpm_smd_send);
+
+static int qcom_icc_rpm_smd_probe(struct platform_device *pdev)
+{
+	icc_rpm_smd.rpm = dev_get_drvdata(pdev->dev.parent);
+	if (!icc_rpm_smd.rpm) {
+		dev_err(&pdev->dev, "unable to retrieve handle to RPM\n");
+		return -ENODEV;
+	}
+
+	return 0;
+}
+
+static const struct of_device_id qcom_icc_rpm_smd_dt_match[] = {
+	{ .compatible = "qcom,interconnect-smd-rpm", },
+	{ },
+};
+
+MODULE_DEVICE_TABLE(of, qcom_interconnect_rpm_smd_dt_match);
+
+static struct platform_driver qcom_interconnect_rpm_smd_driver = {
+	.driver = {
+		.name		= "qcom-interconnect-smd-rpm",
+		.of_match_table	= qcom_icc_rpm_smd_dt_match,
+	},
+	.probe = qcom_icc_rpm_smd_probe,
+};
+
+static int __init rpm_smd_interconnect_init(void)
+{
+	return platform_driver_register(&qcom_interconnect_rpm_smd_driver);
+}
+subsys_initcall(rpm_smd_interconnect_init);
+
+static void __exit rpm_smd_interconnect_exit(void)
+{
+	platform_driver_unregister(&qcom_interconnect_rpm_smd_driver);
+}
+module_exit(rpm_smd_interconnect_exit)
+
+MODULE_AUTHOR("Georgi Djakov <georgi.djakov@linaro.org>");
+MODULE_DESCRIPTION("Qualcomm SMD RPM interconnect driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/interconnect/qcom/smd-rpm.h b/drivers/interconnect/qcom/smd-rpm.h
new file mode 100644
index 000000000000..0f4a3da31cf6
--- /dev/null
+++ b/drivers/interconnect/qcom/smd-rpm.h
@@ -0,0 +1,15 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (c) 2018, Linaro Ltd.
+ * Author: Georgi Djakov <georgi.djakov@linaro.org>
+ */
+
+#ifndef __LINUX_INTERCONNECT_QCOM_RPM_H
+#define __LINUX_INTERCONNECT_QCOM_RPM_H
+
+#include <linux/soc/qcom/smd-rpm.h>
+
+bool qcom_icc_rpm_smd_available(void);
+int qcom_icc_rpm_smd_send(int ctx, int rsc_type, int id, u32 val);
+
+#endif