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Date: Wed, 24 Jul 2019 21:52:06 +0200
From: Benjamin Berg <benjamin@...solutions.net>
To: Srinivas Pandruvada <srinivas.pandruvada@...ux.intel.com>,
rui.zhang@...el.com, edubezval@...il.com
Cc: linux-pm@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] drivers: thermal: processor_thermal_device: Export
sysfs inteface for TCC offset
Tested-by: Benjamin Berg <bberg@...hat.com>
Hi,
this patch allows performance improvements of some machines. It would
be nice if this could still make 5.3.
Benjamin
On Mon, 2019-07-22 at 18:03 -0700, Srinivas Pandruvada wrote:
> This change exports an interface to read tcc offset and allow writing if
> the platform is not locked.
>
> Refer to Intel SDM for details on the MSR: MSR_TEMPERATURE_TARGET.
> Here TCC Activation Offset (R/W) bits allow temperature offset in degrees
> in relation to TjMAX.
>
> This change will be useful for improving performance from user space for
> some platforms, if the current offset is not optimal.
>
> Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@...ux.intel.com>
> ---
> .../processor_thermal_device.c | 91
> ++++++++++++++++++-
> 1 file changed, 87 insertions(+), 4 deletions(-)
>
> diff --git
> a/drivers/thermal/intel/int340x_thermal/processor_thermal_device.c
> b/drivers/thermal/intel/int340x_thermal/processor_thermal_device.c
> index 213ab3cc6b80..a35635129fed 100644
> ---
> a/drivers/thermal/intel/int340x_thermal/processor_thermal_device.c
> +++
> b/drivers/thermal/intel/int340x_thermal/processor_thermal_device.c
> @@ -137,6 +137,72 @@ static const struct attribute_group
> power_limit_attribute_group = {
> .name = "power_limits"
> };
>
> +static ssize_t tcc_offset_degree_celsius_show(struct device *dev,
> + struct device_attribute *attr, char
> *buf)
> +{
> + u64 val;
> + int err;
> +
> + err = rdmsrl_safe(MSR_IA32_TEMPERATURE_TARGET, &val);
> + if (err)
> + return err;
> +
> + val = (val >> 24) & 0xff;
> + return sprintf(buf, "%d\n", (int)val);
> +}
> +
> +static int tcc_offset_update(int tcc)
> +{
> + u64 val;
> + int err;
> +
> + if (!tcc)
> + return -EINVAL;
> +
> + err = rdmsrl_safe(MSR_IA32_TEMPERATURE_TARGET, &val);
> + if (err)
> + return err;
> +
> + val = ~GENMASK_ULL(31, 24);
> + val = (tcc & 0xff) << 24;
> +
> + err = wrmsrl_safe(MSR_IA32_TEMPERATURE_TARGET, val);
> + if (err)
> + return err;
> +
> + return 0;
> +}
> +
> +static int tcc_offset_save;
> +
> +static ssize_t tcc_offset_degree_celsius_store(struct device *dev,
> + struct device_attribute *attr, const
> char *buf,
> + size_t count)
> +{
> + u64 val;
> + int tcc, err;
> +
> + err = rdmsrl_safe(MSR_PLATFORM_INFO, &val);
> + if (err)
> + return err;
> +
> + if (!(val & BIT(30)))
> + return -EACCES;
> +
> + if (kstrtoint(buf, 0, &tcc))
> + return -EINVAL;
> +
> + err = tcc_offset_update(tcc);
> + if (err)
> + return err;
> +
> + tcc_offset_save = tcc;
> +
> + return count;
> +}
> +
> +static DEVICE_ATTR_RW(tcc_offset_degree_celsius);
> +
> static int stored_tjmax; /* since it is fixed, we can have local
> storage */
>
> static int get_tjmax(void)
> @@ -332,6 +398,7 @@ static void proc_thermal_remove(struct
> proc_thermal_device *proc_priv)
> acpi_remove_notify_handler(proc_priv->adev->handle,
> ACPI_DEVICE_NOTIFY,
> proc_thermal_notify);
> int340x_thermal_zone_remove(proc_priv->int340x_zone);
> + sysfs_remove_file(&proc_priv->dev->kobj,
> &dev_attr_tcc_offset_degree_celsius.attr);
> sysfs_remove_group(&proc_priv->dev->kobj,
> &power_limit_attribute_group);
> }
> @@ -355,8 +422,15 @@ static int int3401_add(struct platform_device
> *pdev)
>
> dev_info(&pdev->dev, "Creating sysfs group for
> PROC_THERMAL_PLATFORM_DEV\n");
>
> - return sysfs_create_group(&pdev->dev.kobj,
> - &power_limit_attribute_group);
> + ret = sysfs_create_file(&pdev->dev.kobj,
> &dev_attr_tcc_offset_degree_celsius.attr);
> + if (ret)
> + return ret;
> +
> + ret = sysfs_create_group(&pdev->dev.kobj,
> &power_limit_attribute_group);
> + if (ret)
> + sysfs_remove_file(&pdev->dev.kobj,
> &dev_attr_tcc_offset_degree_celsius.attr);
> +
> + return ret;
> }
>
> static int int3401_remove(struct platform_device *pdev)
> @@ -584,8 +658,15 @@ static int proc_thermal_pci_probe(struct
> pci_dev *pdev,
>
> dev_info(&pdev->dev, "Creating sysfs group for
> PROC_THERMAL_PCI\n");
>
> - return sysfs_create_group(&pdev->dev.kobj,
> - &power_limit_attribute_group);
> + ret = sysfs_create_file(&pdev->dev.kobj,
> &dev_attr_tcc_offset_degree_celsius.attr);
> + if (ret)
> + return ret;
> +
> + ret = sysfs_create_group(&pdev->dev.kobj,
> &power_limit_attribute_group);
> + if (ret)
> + sysfs_remove_file(&pdev->dev.kobj,
> &dev_attr_tcc_offset_degree_celsius.attr);
> +
> + return ret;
> }
>
> static void proc_thermal_pci_remove(struct pci_dev *pdev)
> @@ -611,6 +692,8 @@ static int proc_thermal_resume(struct device
> *dev)
> proc_dev = dev_get_drvdata(dev);
> proc_thermal_read_ppcc(proc_dev);
>
> + tcc_offset_update(tcc_offset_save);
> +
> return 0;
> }
> #else
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