diff mbox series

[2/2] drm/xe/hwmon: Expose power1_max_interval

Message ID 20231006170205.4136927-3-badal.nilawar@intel.com (mailing list archive)
State Handled Elsewhere
Headers show
Series DGFX HWMON Enhancement | expand

Commit Message

Nilawar, Badal Oct. 6, 2023, 5:02 p.m. UTC
Expose power1_max_interval, that is the tau corresponding to PL1, as a
custom hwmon attribute. Some bit manipulation is needed because of the
format of PKG_PWR_LIM_1_TIME in
PACKAGE_RAPL_LIMIT register (1.x * power(2,y))

v2: Get rpm wake ref while accessing power1_max_interval
v3: %s/hwmon/xe_hwmon/
v4:
 - As power1_max_interval is rw attr take lock in read function as well
 - Refine comment about val to fix point conversion (Andi)
 - Update kernel version and date in doc

Acked-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>
Signed-off-by: Badal Nilawar <badal.nilawar@intel.com>
---
 .../ABI/testing/sysfs-driver-intel-xe-hwmon   |   9 ++
 drivers/gpu/drm/xe/regs/xe_mchbar_regs.h      |   8 +
 drivers/gpu/drm/xe/xe_hwmon.c                 | 142 +++++++++++++++++-
 3 files changed, 158 insertions(+), 1 deletion(-)

Comments

Gupta, Anshuman Oct. 11, 2023, 5:59 a.m. UTC | #1
> -----Original Message-----
> From: Nilawar, Badal <badal.nilawar@intel.com>
> Sent: Friday, October 6, 2023 10:32 PM
> To: intel-xe@lists.freedesktop.org; linux-hwmon@vger.kernel.org
> Cc: Gupta, Anshuman <anshuman.gupta@intel.com>; Dixit, Ashutosh
> <ashutosh.dixit@intel.com>; andi.shyti@linux.intel.com; Tauro, Riana
> <riana.tauro@intel.com>; Vivi, Rodrigo <rodrigo.vivi@intel.com>
> Subject: [PATCH 2/2] drm/xe/hwmon: Expose power1_max_interval
> 
> Expose power1_max_interval, that is the tau corresponding to PL1, as a
> custom hwmon attribute. Some bit manipulation is needed because of the
> format of PKG_PWR_LIM_1_TIME in PACKAGE_RAPL_LIMIT register (1.x *
> power(2,y))
> 
> v2: Get rpm wake ref while accessing power1_max_interval
> v3: %s/hwmon/xe_hwmon/
> v4:
>  - As power1_max_interval is rw attr take lock in read function as well
>  - Refine comment about val to fix point conversion (Andi)
>  - Update kernel version and date in doc
> 
> Acked-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
> Reviewed-by: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>
> Signed-off-by: Badal Nilawar <badal.nilawar@intel.com>
> ---
>  .../ABI/testing/sysfs-driver-intel-xe-hwmon   |   9 ++
>  drivers/gpu/drm/xe/regs/xe_mchbar_regs.h      |   8 +
>  drivers/gpu/drm/xe/xe_hwmon.c                 | 142 +++++++++++++++++-
>  3 files changed, 158 insertions(+), 1 deletion(-)
> 
> diff --git a/Documentation/ABI/testing/sysfs-driver-intel-xe-hwmon
> b/Documentation/ABI/testing/sysfs-driver-intel-xe-hwmon
> index 1a7a6c23e141..8c321bc9dc04 100644
> --- a/Documentation/ABI/testing/sysfs-driver-intel-xe-hwmon
> +++ b/Documentation/ABI/testing/sysfs-driver-intel-xe-hwmon
> @@ -59,3 +59,12 @@ Contact:	intel-xe@lists.freedesktop.org
>  Description:	RO. Energy input of device in microjoules.
> 
>  		Only supported for particular Intel xe graphics platforms.
> +
> +What:		/sys/devices/.../hwmon/hwmon<i>/power1_max_interval
> +Date:		October 2023
> +KernelVersion:	6.6
> +Contact:	intel-xe@lists.freedesktop.org
> +Description:	RW. Sustained power limit interval (Tau in PL1/Tau) in
> +		milliseconds over which sustained power is averaged.
> +
> +		Only supported for particular Intel xe graphics platforms.
> diff --git a/drivers/gpu/drm/xe/regs/xe_mchbar_regs.h
> b/drivers/gpu/drm/xe/regs/xe_mchbar_regs.h
> index d8ecbe1858d1..519dd1067a19 100644
> --- a/drivers/gpu/drm/xe/regs/xe_mchbar_regs.h
> +++ b/drivers/gpu/drm/xe/regs/xe_mchbar_regs.h
> @@ -22,15 +22,23 @@
>  #define   PKG_TDP				GENMASK_ULL(14, 0)
>  #define   PKG_MIN_PWR				GENMASK_ULL(30,
> 16)
>  #define   PKG_MAX_PWR				GENMASK_ULL(46,
> 32)
> +#define   PKG_MAX_WIN				GENMASK_ULL(54,
> 48)
> +#define     PKG_MAX_WIN_X			GENMASK_ULL(54, 53)
> +#define     PKG_MAX_WIN_Y			GENMASK_ULL(52, 48)
> +
> 
>  #define PCU_CR_PACKAGE_POWER_SKU_UNIT
> 	XE_REG(MCHBAR_MIRROR_BASE_SNB + 0x5938)
>  #define   PKG_PWR_UNIT				REG_GENMASK(3, 0)
>  #define   PKG_ENERGY_UNIT			REG_GENMASK(12, 8)
> +#define   PKG_TIME_UNIT				REG_GENMASK(19,
> 16)
> 
>  #define PCU_CR_PACKAGE_ENERGY_STATUS
> 	XE_REG(MCHBAR_MIRROR_BASE_SNB + 0x593c)
> 
>  #define PCU_CR_PACKAGE_RAPL_LIMIT
> 	XE_REG(MCHBAR_MIRROR_BASE_SNB + 0x59a0)
>  #define   PKG_PWR_LIM_1				REG_GENMASK(14,
> 0)
>  #define   PKG_PWR_LIM_1_EN			REG_BIT(15)
> +#define   PKG_PWR_LIM_1_TIME			REG_GENMASK(23,
> 17)
> +#define   PKG_PWR_LIM_1_TIME_X			REG_GENMASK(23,
> 22)
> +#define   PKG_PWR_LIM_1_TIME_Y			REG_GENMASK(21,
> 17)
> 
>  #endif /* _XE_MCHBAR_REGS_H_ */
> diff --git a/drivers/gpu/drm/xe/xe_hwmon.c
> b/drivers/gpu/drm/xe/xe_hwmon.c index 391f9a8dd9d7..867481c91826
> 100644
> --- a/drivers/gpu/drm/xe/xe_hwmon.c
> +++ b/drivers/gpu/drm/xe/xe_hwmon.c
> @@ -38,6 +38,7 @@ enum xe_hwmon_reg_operation {
>  #define SF_CURR		1000		/* milliamperes */
>  #define SF_VOLTAGE	1000		/* millivolts */
>  #define SF_ENERGY	1000000		/* microjoules */
> +#define SF_TIME		1000		/* milliseconds */
> 
>  struct xe_hwmon_energy_info {
>  	u32 reg_val_prev;
> @@ -50,6 +51,7 @@ struct xe_hwmon {
>  	struct mutex hwmon_lock;	/* For rw attributes */
>  	int scl_shift_power;
>  	int scl_shift_energy;
> +	int scl_shift_time;
>  	struct xe_hwmon_energy_info ei;	/*  Energy info for
> energy1_input */
>  };
> 
> @@ -253,6 +255,142 @@ xe_hwmon_energy_get(struct xe_hwmon
> *hwmon, long *energy)
>  				  hwmon->scl_shift_energy);
>  }
> 
> +static ssize_t
> +xe_hwmon_power1_max_interval_show(struct device *dev, struct
> device_attribute *attr,
> +				  char *buf)
> +{
> +	struct xe_hwmon *hwmon = dev_get_drvdata(dev);
> +	u32 r, x, y, x_w = 2; /* 2 bits */
> +	u64 tau4, out;
> +
> +	xe_device_mem_access_get(gt_to_xe(hwmon->gt));
> +
> +	mutex_lock(&hwmon->hwmon_lock);
> +
> +	xe_hwmon_process_reg(hwmon, REG_PKG_RAPL_LIMIT,
> +			     REG_READ, &r, 0, 0);
> +
> +	mutex_unlock(&hwmon->hwmon_lock);
> +
> +	xe_device_mem_access_put(gt_to_xe(hwmon->gt));
> +
> +	x = REG_FIELD_GET(PKG_PWR_LIM_1_TIME_X, r);
> +	y = REG_FIELD_GET(PKG_PWR_LIM_1_TIME_Y, r);
Need space here.
> +	/*
> +	 * tau = 1.x * power(2,y), x = bits(23:22), y = bits(21:17)
> +	 *     = (4 | x) << (y - 2)
> +	 * where (y - 2) ensures a 1.x fixed point representation of 1.x
> +	 * However because y can be < 2, we compute
> +	 *     tau4 = (4 | x) << y
> +	 * but add 2 when doing the final right shift to account for units
> +	 */
Please reformat the comment to make it readable.
> +	tau4 = ((1 << x_w) | x) << y;
Need space here.
> +	/* val in hwmon interface units (millisec) */
> +	out = mul_u64_u32_shr(tau4, SF_TIME, hwmon->scl_shift_time +
> x_w);
> +
> +	return sysfs_emit(buf, "%llu\n", out); }
> +
> +static ssize_t
> +xe_hwmon_power1_max_interval_store(struct device *dev, struct
> device_attribute *attr,
> +				   const char *buf, size_t count)
> +{
> +	struct xe_hwmon *hwmon = dev_get_drvdata(dev);
> +	u32 x, y, rxy, x_w = 2; /* 2 bits */
> +	u64 tau4, r, max_win;
> +	unsigned long val;
> +	int ret;
> +
> +	ret = kstrtoul(buf, 0, &val);
> +	if (ret)
> +		return ret;
> +
> +	/*
> +	 * Max HW supported tau in '1.x * power(2,y)' format, x = 0, y = 0x12
> +	 * The hwmon->scl_shift_time default of 0xa results in a max tau of
> 256 seconds
> +	 */
> +#define PKG_MAX_WIN_DEFAULT 0x12ull
Is it universal truth that we are always going to use these default MAX_WIN value ?
AFAIR from i915 review it was due to some h/w limitation on DG2, we were forced to use
these default values instead to read it from registers. If this is true probably  future
platforms will address such h/W limitation, it is worth to leave a code comment here ? 
> +
> +	/*
> +	 * val must be < max in hwmon interface units. The steps below are
> +	 * explained in xe_hwmon_power1_max_interval_show()
> +	 */
> +	r = FIELD_PREP(PKG_MAX_WIN, PKG_MAX_WIN_DEFAULT);
> +	x = REG_FIELD_GET(PKG_MAX_WIN_X, r);
> +	y = REG_FIELD_GET(PKG_MAX_WIN_Y, r);
> +	tau4 = ((1 << x_w) | x) << y;
> +	max_win = mul_u64_u32_shr(tau4, SF_TIME, hwmon->scl_shift_time
> + x_w);
> +
> +	if (val > max_win)
> +		return -EINVAL;
> +
> +	/* val in hw units */
> +	val = DIV_ROUND_CLOSEST_ULL((u64)val << hwmon->scl_shift_time,
> SF_TIME);
Need Space here.
Please leave a line of space before a code comment.
Thanks,
Anshuman Gupta.
> +	/*
> +	 * Convert val to 1.x * power(2,y)
> +	 * y = ilog2(val)
> +	 * x = (val - (1 << y)) >> (y - 2)
> +	 */
> +	if (!val) {
> +		y = 0;
> +		x = 0;
> +	} else {
> +		y = ilog2(val);
> +		x = (val - (1ul << y)) << x_w >> y;
> +	}
> +
> +	rxy = REG_FIELD_PREP(PKG_PWR_LIM_1_TIME_X, x) |
> +REG_FIELD_PREP(PKG_PWR_LIM_1_TIME_Y, y);
> +
> +	xe_device_mem_access_get(gt_to_xe(hwmon->gt));
> +
> +	mutex_lock(&hwmon->hwmon_lock);
> +
> +	xe_hwmon_process_reg(hwmon, REG_PKG_RAPL_LIMIT, REG_RMW,
> (u32 *)&r,
> +			     PKG_PWR_LIM_1_TIME, rxy);
> +
> +	mutex_unlock(&hwmon->hwmon_lock);
> +
> +	xe_device_mem_access_put(gt_to_xe(hwmon->gt));
> +
> +	return count;
> +}
> +
> +static SENSOR_DEVICE_ATTR(power1_max_interval, 0664,
> +			  xe_hwmon_power1_max_interval_show,
> +			  xe_hwmon_power1_max_interval_store, 0);
> +
> +static struct attribute *hwmon_attributes[] = {
> +	&sensor_dev_attr_power1_max_interval.dev_attr.attr,
> +	NULL
> +};
> +
> +static umode_t xe_hwmon_attributes_visible(struct kobject *kobj,
> +					   struct attribute *attr, int index) {
> +	struct device *dev = kobj_to_dev(kobj);
> +	struct xe_hwmon *hwmon = dev_get_drvdata(dev);
> +	int ret = 0;
> +
> +	xe_device_mem_access_get(gt_to_xe(hwmon->gt));
> +
> +	if (attr == &sensor_dev_attr_power1_max_interval.dev_attr.attr)
> +		ret = xe_hwmon_get_reg(hwmon, REG_PKG_RAPL_LIMIT) ?
> attr->mode : 0;
> +
> +	xe_device_mem_access_put(gt_to_xe(hwmon->gt));
> +
> +	return ret;
> +}
> +
> +static const struct attribute_group hwmon_attrgroup = {
> +	.attrs = hwmon_attributes,
> +	.is_visible = xe_hwmon_attributes_visible, };
> +
> +static const struct attribute_group *hwmon_groups[] = {
> +	&hwmon_attrgroup,
> +	NULL
> +};
> +
>  static const struct hwmon_channel_info *hwmon_info[] = {
>  	HWMON_CHANNEL_INFO(power, HWMON_P_MAX |
> HWMON_P_RATED_MAX | HWMON_P_CRIT),
>  	HWMON_CHANNEL_INFO(curr, HWMON_C_CRIT), @@ -574,6
> +712,7 @@ xe_hwmon_get_preregistration_info(struct xe_device *xe)
>  		xe_hwmon_process_reg(hwmon,
> REG_PKG_POWER_SKU_UNIT, REG_READ, &val_sku_unit, 0, 0);
>  		hwmon->scl_shift_power = REG_FIELD_GET(PKG_PWR_UNIT,
> val_sku_unit);
>  		hwmon->scl_shift_energy =
> REG_FIELD_GET(PKG_ENERGY_UNIT, val_sku_unit);
> +		hwmon->scl_shift_time = REG_FIELD_GET(PKG_TIME_UNIT,
> val_sku_unit);
>  	}
> 
>  	/*
> @@ -620,7 +759,8 @@ void xe_hwmon_register(struct xe_device *xe)
>  	/*  hwmon_dev points to device hwmon<i> */
>  	hwmon->hwmon_dev =
> devm_hwmon_device_register_with_info(dev, "xe", hwmon,
> 
> 	&hwmon_chip_info,
> -								NULL);
> +
> 	hwmon_groups);
> +
>  	if (IS_ERR(hwmon->hwmon_dev)) {
>  		drm_warn(&xe->drm, "Failed to register xe hwmon (%pe)\n",
> hwmon->hwmon_dev);
>  		xe->hwmon = NULL;
> --
> 2.25.1
Nilawar, Badal Oct. 16, 2023, 7:39 a.m. UTC | #2
Hi Anshuman,

On 11-10-2023 11:29, Gupta, Anshuman wrote:
> 
> 
>> -----Original Message-----
>> From: Nilawar, Badal <badal.nilawar@intel.com>
>> Sent: Friday, October 6, 2023 10:32 PM
>> To: intel-xe@lists.freedesktop.org; linux-hwmon@vger.kernel.org
>> Cc: Gupta, Anshuman <anshuman.gupta@intel.com>; Dixit, Ashutosh
>> <ashutosh.dixit@intel.com>; andi.shyti@linux.intel.com; Tauro, Riana
>> <riana.tauro@intel.com>; Vivi, Rodrigo <rodrigo.vivi@intel.com>
>> Subject: [PATCH 2/2] drm/xe/hwmon: Expose power1_max_interval
>>
>> Expose power1_max_interval, that is the tau corresponding to PL1, as a
>> custom hwmon attribute. Some bit manipulation is needed because of the
>> format of PKG_PWR_LIM_1_TIME in PACKAGE_RAPL_LIMIT register (1.x *
>> power(2,y))
>>
>> v2: Get rpm wake ref while accessing power1_max_interval
>> v3: %s/hwmon/xe_hwmon/
>> v4:
>>   - As power1_max_interval is rw attr take lock in read function as well
>>   - Refine comment about val to fix point conversion (Andi)
>>   - Update kernel version and date in doc
>>
>> Acked-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
>> Reviewed-by: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>
>> Signed-off-by: Badal Nilawar <badal.nilawar@intel.com>
>> ---
>>   .../ABI/testing/sysfs-driver-intel-xe-hwmon   |   9 ++
>>   drivers/gpu/drm/xe/regs/xe_mchbar_regs.h      |   8 +
>>   drivers/gpu/drm/xe/xe_hwmon.c                 | 142 +++++++++++++++++-
>>   3 files changed, 158 insertions(+), 1 deletion(-)
>>
>> diff --git a/Documentation/ABI/testing/sysfs-driver-intel-xe-hwmon
>> b/Documentation/ABI/testing/sysfs-driver-intel-xe-hwmon
>> index 1a7a6c23e141..8c321bc9dc04 100644
>> --- a/Documentation/ABI/testing/sysfs-driver-intel-xe-hwmon
>> +++ b/Documentation/ABI/testing/sysfs-driver-intel-xe-hwmon
>> @@ -59,3 +59,12 @@ Contact:	intel-xe@lists.freedesktop.org
>>   Description:	RO. Energy input of device in microjoules.
>>
>>   		Only supported for particular Intel xe graphics platforms.
>> +
>> +What:		/sys/devices/.../hwmon/hwmon<i>/power1_max_interval
>> +Date:		October 2023
>> +KernelVersion:	6.6
>> +Contact:	intel-xe@lists.freedesktop.org
>> +Description:	RW. Sustained power limit interval (Tau in PL1/Tau) in
>> +		milliseconds over which sustained power is averaged.
>> +
>> +		Only supported for particular Intel xe graphics platforms.
>> diff --git a/drivers/gpu/drm/xe/regs/xe_mchbar_regs.h
>> b/drivers/gpu/drm/xe/regs/xe_mchbar_regs.h
>> index d8ecbe1858d1..519dd1067a19 100644
>> --- a/drivers/gpu/drm/xe/regs/xe_mchbar_regs.h
>> +++ b/drivers/gpu/drm/xe/regs/xe_mchbar_regs.h
>> @@ -22,15 +22,23 @@
>>   #define   PKG_TDP				GENMASK_ULL(14, 0)
>>   #define   PKG_MIN_PWR				GENMASK_ULL(30,
>> 16)
>>   #define   PKG_MAX_PWR				GENMASK_ULL(46,
>> 32)
>> +#define   PKG_MAX_WIN				GENMASK_ULL(54,
>> 48)
>> +#define     PKG_MAX_WIN_X			GENMASK_ULL(54, 53)
>> +#define     PKG_MAX_WIN_Y			GENMASK_ULL(52, 48)
>> +
>>
>>   #define PCU_CR_PACKAGE_POWER_SKU_UNIT
>> 	XE_REG(MCHBAR_MIRROR_BASE_SNB + 0x5938)
>>   #define   PKG_PWR_UNIT				REG_GENMASK(3, 0)
>>   #define   PKG_ENERGY_UNIT			REG_GENMASK(12, 8)
>> +#define   PKG_TIME_UNIT				REG_GENMASK(19,
>> 16)
>>
>>   #define PCU_CR_PACKAGE_ENERGY_STATUS
>> 	XE_REG(MCHBAR_MIRROR_BASE_SNB + 0x593c)
>>
>>   #define PCU_CR_PACKAGE_RAPL_LIMIT
>> 	XE_REG(MCHBAR_MIRROR_BASE_SNB + 0x59a0)
>>   #define   PKG_PWR_LIM_1				REG_GENMASK(14,
>> 0)
>>   #define   PKG_PWR_LIM_1_EN			REG_BIT(15)
>> +#define   PKG_PWR_LIM_1_TIME			REG_GENMASK(23,
>> 17)
>> +#define   PKG_PWR_LIM_1_TIME_X			REG_GENMASK(23,
>> 22)
>> +#define   PKG_PWR_LIM_1_TIME_Y			REG_GENMASK(21,
>> 17)
>>
>>   #endif /* _XE_MCHBAR_REGS_H_ */
>> diff --git a/drivers/gpu/drm/xe/xe_hwmon.c
>> b/drivers/gpu/drm/xe/xe_hwmon.c index 391f9a8dd9d7..867481c91826
>> 100644
>> --- a/drivers/gpu/drm/xe/xe_hwmon.c
>> +++ b/drivers/gpu/drm/xe/xe_hwmon.c
>> @@ -38,6 +38,7 @@ enum xe_hwmon_reg_operation {
>>   #define SF_CURR		1000		/* milliamperes */
>>   #define SF_VOLTAGE	1000		/* millivolts */
>>   #define SF_ENERGY	1000000		/* microjoules */
>> +#define SF_TIME		1000		/* milliseconds */
>>
>>   struct xe_hwmon_energy_info {
>>   	u32 reg_val_prev;
>> @@ -50,6 +51,7 @@ struct xe_hwmon {
>>   	struct mutex hwmon_lock;	/* For rw attributes */
>>   	int scl_shift_power;
>>   	int scl_shift_energy;
>> +	int scl_shift_time;
>>   	struct xe_hwmon_energy_info ei;	/*  Energy info for
>> energy1_input */
>>   };
>>
>> @@ -253,6 +255,142 @@ xe_hwmon_energy_get(struct xe_hwmon
>> *hwmon, long *energy)
>>   				  hwmon->scl_shift_energy);
>>   }
>>
>> +static ssize_t
>> +xe_hwmon_power1_max_interval_show(struct device *dev, struct
>> device_attribute *attr,
>> +				  char *buf)
>> +{
>> +	struct xe_hwmon *hwmon = dev_get_drvdata(dev);
>> +	u32 r, x, y, x_w = 2; /* 2 bits */
>> +	u64 tau4, out;
>> +
>> +	xe_device_mem_access_get(gt_to_xe(hwmon->gt));
>> +
>> +	mutex_lock(&hwmon->hwmon_lock);
>> +
>> +	xe_hwmon_process_reg(hwmon, REG_PKG_RAPL_LIMIT,
>> +			     REG_READ, &r, 0, 0);
>> +
>> +	mutex_unlock(&hwmon->hwmon_lock);
>> +
>> +	xe_device_mem_access_put(gt_to_xe(hwmon->gt));
>> +
>> +	x = REG_FIELD_GET(PKG_PWR_LIM_1_TIME_X, r);
>> +	y = REG_FIELD_GET(PKG_PWR_LIM_1_TIME_Y, r);
> Need space here.
ok
>> +	/*
>> +	 * tau = 1.x * power(2,y), x = bits(23:22), y = bits(21:17)
>> +	 *     = (4 | x) << (y - 2)
>> +	 * where (y - 2) ensures a 1.x fixed point representation of 1.x
>> +	 * However because y can be < 2, we compute
>> +	 *     tau4 = (4 | x) << y
>> +	 * but add 2 when doing the final right shift to account for units
>> +	 */
> Please reformat the comment to make it readable.
ok
>> +	tau4 = ((1 << x_w) | x) << y;
> Need space here.
ok
>> +	/* val in hwmon interface units (millisec) */
>> +	out = mul_u64_u32_shr(tau4, SF_TIME, hwmon->scl_shift_time +
>> x_w);
>> +
>> +	return sysfs_emit(buf, "%llu\n", out); }
>> +
>> +static ssize_t
>> +xe_hwmon_power1_max_interval_store(struct device *dev, struct
>> device_attribute *attr,
>> +				   const char *buf, size_t count)
>> +{
>> +	struct xe_hwmon *hwmon = dev_get_drvdata(dev);
>> +	u32 x, y, rxy, x_w = 2; /* 2 bits */
>> +	u64 tau4, r, max_win;
>> +	unsigned long val;
>> +	int ret;
>> +
>> +	ret = kstrtoul(buf, 0, &val);
>> +	if (ret)
>> +		return ret;
>> +
>> +	/*
>> +	 * Max HW supported tau in '1.x * power(2,y)' format, x = 0, y = 0x12
>> +	 * The hwmon->scl_shift_time default of 0xa results in a max tau of
>> 256 seconds
>> +	 */
>> +#define PKG_MAX_WIN_DEFAULT 0x12ull
> Is it universal truth that we are always going to use these default MAX_WIN value ?
Not sure about future platforms.
> AFAIR from i915 review it was due to some h/w limitation on DG2, we were forced to use
> these default values instead to read it from registers. If this is true probably  future
> platforms will address such h/W limitation, it is worth to leave a code comment here ?
Sure will add comment here.
>> +
>> +	/*
>> +	 * val must be < max in hwmon interface units. The steps below are
>> +	 * explained in xe_hwmon_power1_max_interval_show()
>> +	 */
>> +	r = FIELD_PREP(PKG_MAX_WIN, PKG_MAX_WIN_DEFAULT);
>> +	x = REG_FIELD_GET(PKG_MAX_WIN_X, r);
>> +	y = REG_FIELD_GET(PKG_MAX_WIN_Y, r);
>> +	tau4 = ((1 << x_w) | x) << y;
>> +	max_win = mul_u64_u32_shr(tau4, SF_TIME, hwmon->scl_shift_time
>> + x_w);
>> +
>> +	if (val > max_win)
>> +		return -EINVAL;
>> +
>> +	/* val in hw units */
>> +	val = DIV_ROUND_CLOSEST_ULL((u64)val << hwmon->scl_shift_time,
>> SF_TIME);
> Need Space here.
> Please leave a line of space before a code comment.
Ok

Regards,
Badal
> Thanks,
> Anshuman Gupta.
>> +	/*
>> +	 * Convert val to 1.x * power(2,y)
>> +	 * y = ilog2(val)
>> +	 * x = (val - (1 << y)) >> (y - 2)
>> +	 */
>> +	if (!val) {
>> +		y = 0;
>> +		x = 0;
>> +	} else {
>> +		y = ilog2(val);
>> +		x = (val - (1ul << y)) << x_w >> y;
>> +	}
>> +
>> +	rxy = REG_FIELD_PREP(PKG_PWR_LIM_1_TIME_X, x) |
>> +REG_FIELD_PREP(PKG_PWR_LIM_1_TIME_Y, y);
>> +
>> +	xe_device_mem_access_get(gt_to_xe(hwmon->gt));
>> +
>> +	mutex_lock(&hwmon->hwmon_lock);
>> +
>> +	xe_hwmon_process_reg(hwmon, REG_PKG_RAPL_LIMIT, REG_RMW,
>> (u32 *)&r,
>> +			     PKG_PWR_LIM_1_TIME, rxy);
>> +
>> +	mutex_unlock(&hwmon->hwmon_lock);
>> +
>> +	xe_device_mem_access_put(gt_to_xe(hwmon->gt));
>> +
>> +	return count;
>> +}
>> +
>> +static SENSOR_DEVICE_ATTR(power1_max_interval, 0664,
>> +			  xe_hwmon_power1_max_interval_show,
>> +			  xe_hwmon_power1_max_interval_store, 0);
>> +
>> +static struct attribute *hwmon_attributes[] = {
>> +	&sensor_dev_attr_power1_max_interval.dev_attr.attr,
>> +	NULL
>> +};
>> +
>> +static umode_t xe_hwmon_attributes_visible(struct kobject *kobj,
>> +					   struct attribute *attr, int index) {
>> +	struct device *dev = kobj_to_dev(kobj);
>> +	struct xe_hwmon *hwmon = dev_get_drvdata(dev);
>> +	int ret = 0;
>> +
>> +	xe_device_mem_access_get(gt_to_xe(hwmon->gt));
>> +
>> +	if (attr == &sensor_dev_attr_power1_max_interval.dev_attr.attr)
>> +		ret = xe_hwmon_get_reg(hwmon, REG_PKG_RAPL_LIMIT) ?
>> attr->mode : 0;
>> +
>> +	xe_device_mem_access_put(gt_to_xe(hwmon->gt));
>> +
>> +	return ret;
>> +}
>> +
>> +static const struct attribute_group hwmon_attrgroup = {
>> +	.attrs = hwmon_attributes,
>> +	.is_visible = xe_hwmon_attributes_visible, };
>> +
>> +static const struct attribute_group *hwmon_groups[] = {
>> +	&hwmon_attrgroup,
>> +	NULL
>> +};
>> +
>>   static const struct hwmon_channel_info *hwmon_info[] = {
>>   	HWMON_CHANNEL_INFO(power, HWMON_P_MAX |
>> HWMON_P_RATED_MAX | HWMON_P_CRIT),
>>   	HWMON_CHANNEL_INFO(curr, HWMON_C_CRIT), @@ -574,6
>> +712,7 @@ xe_hwmon_get_preregistration_info(struct xe_device *xe)
>>   		xe_hwmon_process_reg(hwmon,
>> REG_PKG_POWER_SKU_UNIT, REG_READ, &val_sku_unit, 0, 0);
>>   		hwmon->scl_shift_power = REG_FIELD_GET(PKG_PWR_UNIT,
>> val_sku_unit);
>>   		hwmon->scl_shift_energy =
>> REG_FIELD_GET(PKG_ENERGY_UNIT, val_sku_unit);
>> +		hwmon->scl_shift_time = REG_FIELD_GET(PKG_TIME_UNIT,
>> val_sku_unit);
>>   	}
>>
>>   	/*
>> @@ -620,7 +759,8 @@ void xe_hwmon_register(struct xe_device *xe)
>>   	/*  hwmon_dev points to device hwmon<i> */
>>   	hwmon->hwmon_dev =
>> devm_hwmon_device_register_with_info(dev, "xe", hwmon,
>>
>> 	&hwmon_chip_info,
>> -								NULL);
>> +
>> 	hwmon_groups);
>> +
>>   	if (IS_ERR(hwmon->hwmon_dev)) {
>>   		drm_warn(&xe->drm, "Failed to register xe hwmon (%pe)\n",
>> hwmon->hwmon_dev);
>>   		xe->hwmon = NULL;
>> --
>> 2.25.1
>
diff mbox series

Patch

diff --git a/Documentation/ABI/testing/sysfs-driver-intel-xe-hwmon b/Documentation/ABI/testing/sysfs-driver-intel-xe-hwmon
index 1a7a6c23e141..8c321bc9dc04 100644
--- a/Documentation/ABI/testing/sysfs-driver-intel-xe-hwmon
+++ b/Documentation/ABI/testing/sysfs-driver-intel-xe-hwmon
@@ -59,3 +59,12 @@  Contact:	intel-xe@lists.freedesktop.org
 Description:	RO. Energy input of device in microjoules.
 
 		Only supported for particular Intel xe graphics platforms.
+
+What:		/sys/devices/.../hwmon/hwmon<i>/power1_max_interval
+Date:		October 2023
+KernelVersion:	6.6
+Contact:	intel-xe@lists.freedesktop.org
+Description:	RW. Sustained power limit interval (Tau in PL1/Tau) in
+		milliseconds over which sustained power is averaged.
+
+		Only supported for particular Intel xe graphics platforms.
diff --git a/drivers/gpu/drm/xe/regs/xe_mchbar_regs.h b/drivers/gpu/drm/xe/regs/xe_mchbar_regs.h
index d8ecbe1858d1..519dd1067a19 100644
--- a/drivers/gpu/drm/xe/regs/xe_mchbar_regs.h
+++ b/drivers/gpu/drm/xe/regs/xe_mchbar_regs.h
@@ -22,15 +22,23 @@ 
 #define   PKG_TDP				GENMASK_ULL(14, 0)
 #define   PKG_MIN_PWR				GENMASK_ULL(30, 16)
 #define   PKG_MAX_PWR				GENMASK_ULL(46, 32)
+#define   PKG_MAX_WIN				GENMASK_ULL(54, 48)
+#define     PKG_MAX_WIN_X			GENMASK_ULL(54, 53)
+#define     PKG_MAX_WIN_Y			GENMASK_ULL(52, 48)
+
 
 #define PCU_CR_PACKAGE_POWER_SKU_UNIT		XE_REG(MCHBAR_MIRROR_BASE_SNB + 0x5938)
 #define   PKG_PWR_UNIT				REG_GENMASK(3, 0)
 #define   PKG_ENERGY_UNIT			REG_GENMASK(12, 8)
+#define   PKG_TIME_UNIT				REG_GENMASK(19, 16)
 
 #define PCU_CR_PACKAGE_ENERGY_STATUS		XE_REG(MCHBAR_MIRROR_BASE_SNB + 0x593c)
 
 #define PCU_CR_PACKAGE_RAPL_LIMIT		XE_REG(MCHBAR_MIRROR_BASE_SNB + 0x59a0)
 #define   PKG_PWR_LIM_1				REG_GENMASK(14, 0)
 #define   PKG_PWR_LIM_1_EN			REG_BIT(15)
+#define   PKG_PWR_LIM_1_TIME			REG_GENMASK(23, 17)
+#define   PKG_PWR_LIM_1_TIME_X			REG_GENMASK(23, 22)
+#define   PKG_PWR_LIM_1_TIME_Y			REG_GENMASK(21, 17)
 
 #endif /* _XE_MCHBAR_REGS_H_ */
diff --git a/drivers/gpu/drm/xe/xe_hwmon.c b/drivers/gpu/drm/xe/xe_hwmon.c
index 391f9a8dd9d7..867481c91826 100644
--- a/drivers/gpu/drm/xe/xe_hwmon.c
+++ b/drivers/gpu/drm/xe/xe_hwmon.c
@@ -38,6 +38,7 @@  enum xe_hwmon_reg_operation {
 #define SF_CURR		1000		/* milliamperes */
 #define SF_VOLTAGE	1000		/* millivolts */
 #define SF_ENERGY	1000000		/* microjoules */
+#define SF_TIME		1000		/* milliseconds */
 
 struct xe_hwmon_energy_info {
 	u32 reg_val_prev;
@@ -50,6 +51,7 @@  struct xe_hwmon {
 	struct mutex hwmon_lock;	/* For rw attributes */
 	int scl_shift_power;
 	int scl_shift_energy;
+	int scl_shift_time;
 	struct xe_hwmon_energy_info ei;	/*  Energy info for energy1_input */
 };
 
@@ -253,6 +255,142 @@  xe_hwmon_energy_get(struct xe_hwmon *hwmon, long *energy)
 				  hwmon->scl_shift_energy);
 }
 
+static ssize_t
+xe_hwmon_power1_max_interval_show(struct device *dev, struct device_attribute *attr,
+				  char *buf)
+{
+	struct xe_hwmon *hwmon = dev_get_drvdata(dev);
+	u32 r, x, y, x_w = 2; /* 2 bits */
+	u64 tau4, out;
+
+	xe_device_mem_access_get(gt_to_xe(hwmon->gt));
+
+	mutex_lock(&hwmon->hwmon_lock);
+
+	xe_hwmon_process_reg(hwmon, REG_PKG_RAPL_LIMIT,
+			     REG_READ, &r, 0, 0);
+
+	mutex_unlock(&hwmon->hwmon_lock);
+
+	xe_device_mem_access_put(gt_to_xe(hwmon->gt));
+
+	x = REG_FIELD_GET(PKG_PWR_LIM_1_TIME_X, r);
+	y = REG_FIELD_GET(PKG_PWR_LIM_1_TIME_Y, r);
+	/*
+	 * tau = 1.x * power(2,y), x = bits(23:22), y = bits(21:17)
+	 *     = (4 | x) << (y - 2)
+	 * where (y - 2) ensures a 1.x fixed point representation of 1.x
+	 * However because y can be < 2, we compute
+	 *     tau4 = (4 | x) << y
+	 * but add 2 when doing the final right shift to account for units
+	 */
+	tau4 = ((1 << x_w) | x) << y;
+	/* val in hwmon interface units (millisec) */
+	out = mul_u64_u32_shr(tau4, SF_TIME, hwmon->scl_shift_time + x_w);
+
+	return sysfs_emit(buf, "%llu\n", out);
+}
+
+static ssize_t
+xe_hwmon_power1_max_interval_store(struct device *dev, struct device_attribute *attr,
+				   const char *buf, size_t count)
+{
+	struct xe_hwmon *hwmon = dev_get_drvdata(dev);
+	u32 x, y, rxy, x_w = 2; /* 2 bits */
+	u64 tau4, r, max_win;
+	unsigned long val;
+	int ret;
+
+	ret = kstrtoul(buf, 0, &val);
+	if (ret)
+		return ret;
+
+	/*
+	 * Max HW supported tau in '1.x * power(2,y)' format, x = 0, y = 0x12
+	 * The hwmon->scl_shift_time default of 0xa results in a max tau of 256 seconds
+	 */
+#define PKG_MAX_WIN_DEFAULT 0x12ull
+
+	/*
+	 * val must be < max in hwmon interface units. The steps below are
+	 * explained in xe_hwmon_power1_max_interval_show()
+	 */
+	r = FIELD_PREP(PKG_MAX_WIN, PKG_MAX_WIN_DEFAULT);
+	x = REG_FIELD_GET(PKG_MAX_WIN_X, r);
+	y = REG_FIELD_GET(PKG_MAX_WIN_Y, r);
+	tau4 = ((1 << x_w) | x) << y;
+	max_win = mul_u64_u32_shr(tau4, SF_TIME, hwmon->scl_shift_time + x_w);
+
+	if (val > max_win)
+		return -EINVAL;
+
+	/* val in hw units */
+	val = DIV_ROUND_CLOSEST_ULL((u64)val << hwmon->scl_shift_time, SF_TIME);
+	/*
+	 * Convert val to 1.x * power(2,y)
+	 * y = ilog2(val)
+	 * x = (val - (1 << y)) >> (y - 2)
+	 */
+	if (!val) {
+		y = 0;
+		x = 0;
+	} else {
+		y = ilog2(val);
+		x = (val - (1ul << y)) << x_w >> y;
+	}
+
+	rxy = REG_FIELD_PREP(PKG_PWR_LIM_1_TIME_X, x) | REG_FIELD_PREP(PKG_PWR_LIM_1_TIME_Y, y);
+
+	xe_device_mem_access_get(gt_to_xe(hwmon->gt));
+
+	mutex_lock(&hwmon->hwmon_lock);
+
+	xe_hwmon_process_reg(hwmon, REG_PKG_RAPL_LIMIT, REG_RMW, (u32 *)&r,
+			     PKG_PWR_LIM_1_TIME, rxy);
+
+	mutex_unlock(&hwmon->hwmon_lock);
+
+	xe_device_mem_access_put(gt_to_xe(hwmon->gt));
+
+	return count;
+}
+
+static SENSOR_DEVICE_ATTR(power1_max_interval, 0664,
+			  xe_hwmon_power1_max_interval_show,
+			  xe_hwmon_power1_max_interval_store, 0);
+
+static struct attribute *hwmon_attributes[] = {
+	&sensor_dev_attr_power1_max_interval.dev_attr.attr,
+	NULL
+};
+
+static umode_t xe_hwmon_attributes_visible(struct kobject *kobj,
+					   struct attribute *attr, int index)
+{
+	struct device *dev = kobj_to_dev(kobj);
+	struct xe_hwmon *hwmon = dev_get_drvdata(dev);
+	int ret = 0;
+
+	xe_device_mem_access_get(gt_to_xe(hwmon->gt));
+
+	if (attr == &sensor_dev_attr_power1_max_interval.dev_attr.attr)
+		ret = xe_hwmon_get_reg(hwmon, REG_PKG_RAPL_LIMIT) ? attr->mode : 0;
+
+	xe_device_mem_access_put(gt_to_xe(hwmon->gt));
+
+	return ret;
+}
+
+static const struct attribute_group hwmon_attrgroup = {
+	.attrs = hwmon_attributes,
+	.is_visible = xe_hwmon_attributes_visible,
+};
+
+static const struct attribute_group *hwmon_groups[] = {
+	&hwmon_attrgroup,
+	NULL
+};
+
 static const struct hwmon_channel_info *hwmon_info[] = {
 	HWMON_CHANNEL_INFO(power, HWMON_P_MAX | HWMON_P_RATED_MAX | HWMON_P_CRIT),
 	HWMON_CHANNEL_INFO(curr, HWMON_C_CRIT),
@@ -574,6 +712,7 @@  xe_hwmon_get_preregistration_info(struct xe_device *xe)
 		xe_hwmon_process_reg(hwmon, REG_PKG_POWER_SKU_UNIT, REG_READ, &val_sku_unit, 0, 0);
 		hwmon->scl_shift_power = REG_FIELD_GET(PKG_PWR_UNIT, val_sku_unit);
 		hwmon->scl_shift_energy = REG_FIELD_GET(PKG_ENERGY_UNIT, val_sku_unit);
+		hwmon->scl_shift_time = REG_FIELD_GET(PKG_TIME_UNIT, val_sku_unit);
 	}
 
 	/*
@@ -620,7 +759,8 @@  void xe_hwmon_register(struct xe_device *xe)
 	/*  hwmon_dev points to device hwmon<i> */
 	hwmon->hwmon_dev = devm_hwmon_device_register_with_info(dev, "xe", hwmon,
 								&hwmon_chip_info,
-								NULL);
+								hwmon_groups);
+
 	if (IS_ERR(hwmon->hwmon_dev)) {
 		drm_warn(&xe->drm, "Failed to register xe hwmon (%pe)\n", hwmon->hwmon_dev);
 		xe->hwmon = NULL;