From 71aa3693493d5f51822d88cdd26bc5a51ae5544f Mon Sep 17 00:00:00 2001 From: Talel Shenhar Date: Thu, 11 Apr 2019 13:22:48 +0300 Subject: [PATCH] thermal: Introduce Amazon's Annapurna Labs Thermal Driver This is a generic thermal driver for simple MMIO sensors, of which amazon,al-thermal is one. This device uses a single MMIO transaction to read the temperature and report it to the thermal subsystem. Signed-off-by: Talel Shenhar Reviewed-by: David Woodhouse Reviewed-by: Daniel Lezcano Signed-off-by: Eduardo Valentin --- MAINTAINERS | 6 ++ drivers/thermal/Kconfig | 10 ++++ drivers/thermal/Makefile | 1 + drivers/thermal/thermal_mmio.c | 129 +++++++++++++++++++++++++++++++++++++++++ 4 files changed, 146 insertions(+) create mode 100644 drivers/thermal/thermal_mmio.c diff --git a/MAINTAINERS b/MAINTAINERS index 5c38f21..4d08f59 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -744,6 +744,12 @@ S: Supported F: Documentation/networking/device_drivers/amazon/ena.txt F: drivers/net/ethernet/amazon/ +AMAZON ANNAPURNA LABS THERMAL MMIO DRIVER +M: Talel Shenhar +S: Maintained +F: Documentation/devicetree/bindings/thermal/amazon,al-thermal.txt +F: drivers/thermal/thermal_mmio.c + AMD CRYPTOGRAPHIC COPROCESSOR (CCP) DRIVER M: Tom Lendacky M: Gary Hook diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig index 653aa27..41f3943 100644 --- a/drivers/thermal/Kconfig +++ b/drivers/thermal/Kconfig @@ -200,6 +200,16 @@ config THERMAL_EMULATION because userland can easily disable the thermal policy by simply flooding this sysfs node with low temperature values. +config THERMAL_MMIO + tristate "Generic Thermal MMIO driver" + depends on OF || COMPILE_TEST + help + This option enables the generic thermal MMIO driver that will use + memory-mapped reads to get the temperature. Any HW/System that + allows temperature reading by a single memory-mapped reading, be it + register or shared memory, is a potential candidate to work with this + driver. + config HISI_THERMAL tristate "Hisilicon thermal driver" depends on ARCH_HISI || COMPILE_TEST diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile index 486d682..74a37c7 100644 --- a/drivers/thermal/Makefile +++ b/drivers/thermal/Makefile @@ -29,6 +29,7 @@ thermal_sys-$(CONFIG_DEVFREQ_THERMAL) += devfreq_cooling.o # platform thermal drivers obj-y += broadcom/ +obj-$(CONFIG_THERMAL_MMIO) += thermal_mmio.o obj-$(CONFIG_SPEAR_THERMAL) += spear_thermal.o obj-$(CONFIG_ROCKCHIP_THERMAL) += rockchip_thermal.o obj-$(CONFIG_RCAR_THERMAL) += rcar_thermal.o diff --git a/drivers/thermal/thermal_mmio.c b/drivers/thermal/thermal_mmio.c new file mode 100644 index 0000000..de3cceea --- /dev/null +++ b/drivers/thermal/thermal_mmio.c @@ -0,0 +1,129 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. + */ + +#include +#include +#include +#include + +struct thermal_mmio { + void __iomem *mmio_base; + u32 (*read_mmio)(void __iomem *mmio_base); + u32 mask; + int factor; +}; + +static u32 thermal_mmio_readb(void __iomem *mmio_base) +{ + return readb(mmio_base); +} + +static int thermal_mmio_get_temperature(void *private, int *temp) +{ + int t; + struct thermal_mmio *sensor = + (struct thermal_mmio *)private; + + t = sensor->read_mmio(sensor->mmio_base) & sensor->mask; + t *= sensor->factor; + + *temp = t; + + return 0; +} + +static struct thermal_zone_of_device_ops thermal_mmio_ops = { + .get_temp = thermal_mmio_get_temperature, +}; + +static int thermal_mmio_probe(struct platform_device *pdev) +{ + struct resource *resource; + struct thermal_mmio *sensor; + int (*sensor_init_func)(struct platform_device *pdev, + struct thermal_mmio *sensor); + struct thermal_zone_device *thermal_zone; + int ret; + int temperature; + + sensor = devm_kzalloc(&pdev->dev, sizeof(*sensor), GFP_KERNEL); + if (!sensor) + return -ENOMEM; + + resource = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (IS_ERR(resource)) { + dev_err(&pdev->dev, + "fail to get platform memory resource (%ld)\n", + PTR_ERR(resource)); + return PTR_ERR(resource); + } + + sensor->mmio_base = devm_ioremap_resource(&pdev->dev, resource); + if (IS_ERR(sensor->mmio_base)) { + dev_err(&pdev->dev, "failed to ioremap memory (%ld)\n", + PTR_ERR(sensor->mmio_base)); + return PTR_ERR(sensor->mmio_base); + } + + sensor_init_func = device_get_match_data(&pdev->dev); + if (sensor_init_func) { + ret = sensor_init_func(pdev, sensor); + if (ret) { + dev_err(&pdev->dev, + "failed to initialize sensor (%d)\n", + ret); + return ret; + } + } + + thermal_zone = devm_thermal_zone_of_sensor_register(&pdev->dev, + 0, + sensor, + &thermal_mmio_ops); + if (IS_ERR(thermal_zone)) { + dev_err(&pdev->dev, + "failed to register sensor (%ld)\n", + PTR_ERR(thermal_zone)); + return PTR_ERR(thermal_zone); + } + + thermal_mmio_get_temperature(sensor, &temperature); + dev_info(&pdev->dev, + "thermal mmio sensor %s registered, current temperature: %d\n", + pdev->name, temperature); + + return 0; +} + +static int al_thermal_init(struct platform_device *pdev, + struct thermal_mmio *sensor) +{ + sensor->read_mmio = thermal_mmio_readb; + sensor->mask = 0xff; + sensor->factor = 1000; + + return 0; +} + +static const struct of_device_id thermal_mmio_id_table[] = { + { .compatible = "amazon,al-thermal", .data = al_thermal_init}, + {} +}; +MODULE_DEVICE_TABLE(of, thermal_mmio_id_table); + +static struct platform_driver thermal_mmio_driver = { + .probe = thermal_mmio_probe, + .driver = { + .name = "thermal-mmio", + .owner = THIS_MODULE, + .of_match_table = of_match_ptr(thermal_mmio_id_table), + }, +}; + +module_platform_driver(thermal_mmio_driver); + +MODULE_AUTHOR("Talel Shenhar "); +MODULE_DESCRIPTION("Thermal MMIO Driver"); +MODULE_LICENSE("GPL v2"); -- 2.7.4