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.dja...@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. + +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.dja...@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.dja...@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.dja...@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