Re: [PATCH 4/4] thermal: Add Tegra BPMP thermal sensor driver

From: Eduardo Valentin
Date: Fri Jun 30 2017 - 22:53:41 EST


Hey Mikko,

Sorry for the late answer,

On Fri, Jun 16, 2017 at 02:28:25PM +0300, Mikko Perttunen wrote:
> On Tegra186, the BPMP (Boot and Power Management Processor) exposes an
> interface to thermal sensors on the system-on-chip. This driver
> implements access to the interface. It supports reading the
> temperature, setting trip points and receiving notification of a
> tripped trip point.
>
> Signed-off-by: Mikko Perttunen <mperttunen@xxxxxxxxxx>
> ---
> drivers/thermal/Makefile | 2 +-
> drivers/thermal/tegra/Kconfig | 7 +
> drivers/thermal/tegra/Makefile | 3 +-
> drivers/thermal/tegra/bpmp-thermal.c | 253 +++++++++++++++++++++++++++++++++++
> 4 files changed, 263 insertions(+), 2 deletions(-)
> create mode 100644 drivers/thermal/tegra/bpmp-thermal.c
>
> diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
> index 094d7039981c..c03dccdba7b8 100644
> --- a/drivers/thermal/Makefile
> +++ b/drivers/thermal/Makefile
> @@ -54,7 +54,7 @@ obj-$(CONFIG_INTEL_BXT_PMIC_THERMAL) += intel_bxt_pmic_thermal.o
> obj-$(CONFIG_INTEL_PCH_THERMAL) += intel_pch_thermal.o
> obj-$(CONFIG_ST_THERMAL) += st/
> obj-$(CONFIG_QCOM_TSENS) += qcom/
> -obj-$(CONFIG_TEGRA_SOCTHERM) += tegra/
> +obj-y += tegra/
> obj-$(CONFIG_HISI_THERMAL) += hisi_thermal.o
> obj-$(CONFIG_MTK_THERMAL) += mtk_thermal.o
> obj-$(CONFIG_GENERIC_ADC_THERMAL) += thermal-generic-adc.o
> diff --git a/drivers/thermal/tegra/Kconfig b/drivers/thermal/tegra/Kconfig
> index cec586ec7e4b..36e4b03bb98b 100644
> --- a/drivers/thermal/tegra/Kconfig
> +++ b/drivers/thermal/tegra/Kconfig
> @@ -10,4 +10,11 @@ config TEGRA_SOCTHERM
> zones to manage temperatures. This option is also required for the
> emergency thermal reset (thermtrip) feature to function.
>
> +config TEGRA_BPMP_THERMAL
> + tristate "Tegra BPMP thermal sensing"
> + depends on TEGRA_BPMP

Can you add COMPILE_TEST support here?

> + help
> + Enable this option for support for sensing system temperature of NVIDIA
> + Tegra systems-on-chip with the BPMP coprocessor (Tegra186).
> +
> endmenu
> diff --git a/drivers/thermal/tegra/Makefile b/drivers/thermal/tegra/Makefile
> index 1ce1af2cf0f5..757abcd1feaf 100644
> --- a/drivers/thermal/tegra/Makefile
> +++ b/drivers/thermal/tegra/Makefile
> @@ -1,4 +1,5 @@
> -obj-$(CONFIG_TEGRA_SOCTHERM) += tegra-soctherm.o
> +obj-$(CONFIG_TEGRA_SOCTHERM) += tegra-soctherm.o
> +obj-$(CONFIG_TEGRA_BPMP_THERMAL) += bpmp-thermal.o
>
> tegra-soctherm-y := soctherm.o soctherm-fuse.o
> tegra-soctherm-$(CONFIG_ARCH_TEGRA_124_SOC) += tegra124-soctherm.o
> diff --git a/drivers/thermal/tegra/bpmp-thermal.c b/drivers/thermal/tegra/bpmp-thermal.c
> new file mode 100644
> index 000000000000..3465a201d1ac
> --- /dev/null
> +++ b/drivers/thermal/tegra/bpmp-thermal.c
> @@ -0,0 +1,253 @@
> +/*
> + * Copyright (c) 2015-2017, NVIDIA CORPORATION. All rights reserved.
> + *
> + * Author:
> + * Mikko Perttunen <mperttunen@xxxxxxxxxx>
> + * Aapo Vienamo <avienamo@xxxxxxxxxx>
> + *
> + * This software is licensed under the terms of the GNU General Public
> + * License version 2, as published by the Free Software Foundation, and
> + * may be copied, distributed, and modified under those terms.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License for more details.
> + *
> + */
> +
> +#include <linux/err.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/thermal.h>
> +#include <linux/workqueue.h>
> +
> +#include <soc/tegra/bpmp.h>
> +#include <soc/tegra/bpmp-abi.h>
> +
> +struct tegra_bpmp_thermal_zone {
> + struct tegra_bpmp_thermal *tegra;
> + struct thermal_zone_device *tzd;
> + struct work_struct tz_device_update_work;
> + unsigned int idx;
> +};
> +
> +struct tegra_bpmp_thermal {
> + struct device *dev;
> + struct tegra_bpmp *bpmp;
> + unsigned int num_zones;
> + struct tegra_bpmp_thermal_zone *zones;
> +};
> +
> +static int tegra_bpmp_thermal_get_temp(void *data, int *out_temp)
> +{
> + struct tegra_bpmp_thermal_zone *zone = data;
> + struct mrq_thermal_host_to_bpmp_request req;
> + union mrq_thermal_bpmp_to_host_response reply;
> + struct tegra_bpmp_message msg;
> + int err;
> +
> + memset(&req, 0, sizeof(req));
> + req.type = CMD_THERMAL_GET_TEMP;
> + req.get_temp.zone = zone->idx;
> +
> + memset(&msg, 0, sizeof(msg));
> + msg.mrq = MRQ_THERMAL;
> + msg.tx.data = &req;
> + msg.tx.size = sizeof(req);
> + msg.rx.data = &reply;
> + msg.rx.size = sizeof(reply);
> +
> + err = tegra_bpmp_transfer(zone->tegra->bpmp, &msg);
> + if (err)
> + return err;
> +
> + *out_temp = reply.get_temp.temp;
> +
> + return 0;
> +}
> +
> +static int tegra_bpmp_thermal_set_trips(void *data, int low, int high)
> +{
> + struct tegra_bpmp_thermal_zone *zone = data;
> + struct mrq_thermal_host_to_bpmp_request req;
> + struct tegra_bpmp_message msg;
> +
> + memset(&req, 0, sizeof(req));
> + req.type = CMD_THERMAL_SET_TRIP;
> + req.set_trip.zone = zone->idx;
> + req.set_trip.enabled = true;
> + req.set_trip.low = low;
> + req.set_trip.high = high;
> +
> + memset(&msg, 0, sizeof(msg));
> + msg.mrq = MRQ_THERMAL;
> + msg.tx.data = &req;
> + msg.tx.size = sizeof(req);
> +
> + return tegra_bpmp_transfer(zone->tegra->bpmp, &msg);
> +}
> +
> +static void tz_device_update_work_fn(struct work_struct *work)
> +{
> + struct tegra_bpmp_thermal_zone *zone;
> +
> + zone = container_of(work, struct tegra_bpmp_thermal_zone,
> + tz_device_update_work);
> +
> + thermal_zone_device_update(zone->tzd, THERMAL_TRIP_VIOLATED);
> +}
> +
> +static void bpmp_mrq_thermal(unsigned int mrq, struct tegra_bpmp_channel *ch,
> + void *data)
> +{
> + struct mrq_thermal_bpmp_to_host_request *req;
> + struct tegra_bpmp_thermal *tegra = data;
> + int zone_idx;
> +
> + req = (struct mrq_thermal_bpmp_to_host_request *)ch->ib->data;
> +
> + if (req->type != CMD_THERMAL_HOST_TRIP_REACHED) {
> + dev_err(tegra->dev, "%s: invalid request type: %d\n",
> + __func__, req->type);
> + tegra_bpmp_mrq_return(ch, -EINVAL, NULL, 0);
> + return;
> + }
> +
> + zone_idx = req->host_trip_reached.zone;
> + if (zone_idx >= tegra->num_zones) {
> + dev_err(tegra->dev, "%s: invalid thermal zone: %d\n",
> + __func__, zone_idx);
> + tegra_bpmp_mrq_return(ch, -EINVAL, NULL, 0);
> + return;
> + }
> +
> + tegra_bpmp_mrq_return(ch, 0, NULL, 0);
> +
> + schedule_work(&tegra->zones[zone_idx].tz_device_update_work);

Why not a thermal update right here?

> +}
> +
> +static int tegra_bpmp_thermal_get_num_zones(struct tegra_bpmp *bpmp,
> + int *num_zones)
> +{
> + struct mrq_thermal_host_to_bpmp_request req;
> + union mrq_thermal_bpmp_to_host_response reply;
> + struct tegra_bpmp_message msg;
> + int err;
> +
> + memset(&req, 0, sizeof(req));
> + req.type = CMD_THERMAL_GET_NUM_ZONES;
> +
> + memset(&msg, 0, sizeof(msg));
> + msg.mrq = MRQ_THERMAL;
> + msg.tx.data = &req;
> + msg.tx.size = sizeof(req);
> + msg.rx.data = &reply;
> + msg.rx.size = sizeof(reply);
> +
> + err = tegra_bpmp_transfer(bpmp, &msg);
> + if (err)
> + return err;
> +
> + *num_zones = reply.get_num_zones.num;
> +
> + return 0;
> +}
> +
> +static const struct thermal_zone_of_device_ops tegra_bpmp_of_thermal_ops = {
> + .get_temp = tegra_bpmp_thermal_get_temp,
> + .set_trips = tegra_bpmp_thermal_set_trips,
> +};
> +
> +static int tegra_bpmp_thermal_probe(struct platform_device *pdev)
> +{
> + struct tegra_bpmp *bpmp = dev_get_drvdata(pdev->dev.parent);
> + struct tegra_bpmp_thermal *tegra;
> + struct thermal_zone_device *tzd;
> + unsigned int i;
> + int err;
> +
> + tegra = devm_kzalloc(&pdev->dev, sizeof(*tegra), GFP_KERNEL);
> + if (!tegra)
> + return -ENOMEM;
> +
> + tegra->dev = &pdev->dev;
> + tegra->bpmp = bpmp;
> +
> + err = tegra_bpmp_thermal_get_num_zones(bpmp, &tegra->num_zones);
> + if (err) {
> + dev_err(&pdev->dev, "failed to get the number of zones: %d\n",
> + err);
> + return err;
> + }
> +
> + tegra->zones = devm_kcalloc(&pdev->dev, tegra->num_zones,
> + sizeof(*tegra->zones), GFP_KERNEL);
> + if (!tegra->zones)
> + return -ENOMEM;
> +
> + for (i = 0; i < tegra->num_zones; ++i) {
> + int temp;
> +
> + tegra->zones[i].idx = i;
> + tegra->zones[i].tegra = tegra;
> +
> + err = tegra_bpmp_thermal_get_temp(&tegra->zones[i], &temp);
> + if (err < 0)
> + continue;

Should we release the memory allocated for zones that fail to retrieve
temperature here, given that you are not going to use it elsewhere.

> +
> + tzd = devm_thermal_zone_of_sensor_register(
> + &pdev->dev, i, &tegra->zones[i],
> + &tegra_bpmp_of_thermal_ops);
> + if (IS_ERR(tzd)) {
> + if (PTR_ERR(tzd) == -EPROBE_DEFER)
> + return -EPROBE_DEFER;
> + continue;

same here?

> + }
> +
> + tegra->zones[i].tzd = tzd;
> + INIT_WORK(&tegra->zones[i].tz_device_update_work,
> + tz_device_update_work_fn);
> + }
> +
> + err = tegra_bpmp_request_mrq(bpmp, MRQ_THERMAL, bpmp_mrq_thermal,
> + tegra);
> + if (err) {
> + dev_err(&pdev->dev, "failed to register mrq handler: %d\n",
> + err);
> + return err;
> + }
> +
> + platform_set_drvdata(pdev, tegra);
> +
> + return 0;
> +}
> +
> +static int tegra_bpmp_thermal_remove(struct platform_device *pdev)
> +{
> + struct tegra_bpmp_thermal *tegra = platform_get_drvdata(pdev);
> +
> + tegra_bpmp_free_mrq(tegra->bpmp, MRQ_THERMAL, tegra);
> +
> + return 0;
> +}
> +
> +static const struct of_device_id tegra_bpmp_thermal_of_match[] = {
> + { .compatible = "nvidia,tegra186-bpmp-thermal" },
> + { },
> +};
> +MODULE_DEVICE_TABLE(of, tegra_bpmp_thermal_of_match);
> +
> +static struct platform_driver tegra_bpmp_thermal_driver = {
> + .probe = tegra_bpmp_thermal_probe,
> + .remove = tegra_bpmp_thermal_remove,
> + .driver = {
> + .name = "tegra-bpmp-thermal",
> + .of_match_table = tegra_bpmp_thermal_of_match,
> + },
> +};
> +module_platform_driver(tegra_bpmp_thermal_driver);
> +
> +MODULE_AUTHOR("Mikko Perttunen <mperttunen@xxxxxxxxxx>");
> +MODULE_DESCRIPTION("NVIDIA Tegra BPMP thermal sensor driver");
> +MODULE_LICENSE("GPL v2");
> --
> 2.13.1
>