Commit 8c90dc68 authored by James Morse's avatar James Morse Committed by Catalin Marinas
Browse files

arm_mpam: Probe the hardware features resctrl supports 



Expand the probing support with the control and monitor types
we can use with resctrl.

CC: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: default avatarJames Morse <james.morse@arm.com>
Reviewed-by: default avatarJonathan Cameron <jonathan.cameron@huawei.com>
Reviewed-by: default avatarFenghua Yu <fenghuay@nvidia.com>
Reviewed-by: default avatarGavin Shan <gshan@redhat.com>
Reviewed-by: default avatarShaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: default avatarFenghua Yu <fenghuay@nvidia.com>
Tested-by: default avatarShaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: default avatarPeter Newman <peternewman@google.com>
Tested-by: default avatarCarl Worth <carl@os.amperecomputing.com>
Tested-by: default avatarGavin Shan <gshan@redhat.com>
Tested-by: default avatarZeng Heng <zengheng4@huawei.com>
Tested-by: default avatarHanjun Guo <guohanjun@huawei.com>
Signed-off-by: default avatarBen Horgan <ben.horgan@arm.com>
Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
parent d02beb06

drivers/resctrl/mpam_devices.c

+149 −0
Original line number Diff line number Diff line
@@ -170,6 +170,22 @@ static inline void _mpam_write_partsel_reg(struct mpam_msc *msc, u16 reg, u32 va 


#define mpam_write_partsel_reg(msc, reg, val)  _mpam_write_partsel_reg(msc, MPAMCFG_##reg, val)



static inline u32 _mpam_read_monsel_reg(struct mpam_msc *msc, u16 reg)

{

	mpam_mon_sel_lock_held(msc);

	return __mpam_read_reg(msc, reg);

}



#define mpam_read_monsel_reg(msc, reg) _mpam_read_monsel_reg(msc, MSMON_##reg)



static inline void _mpam_write_monsel_reg(struct mpam_msc *msc, u16 reg, u32 val)

{

	mpam_mon_sel_lock_held(msc);

	__mpam_write_reg(msc, reg, val);

}



#define mpam_write_monsel_reg(msc, reg, val)   _mpam_write_monsel_reg(msc, MSMON_##reg, val)



static u64 mpam_msc_read_idr(struct mpam_msc *msc)

{

	u64 idr_high = 0, idr_low;
@@ -548,6 +564,133 @@ static struct mpam_msc_ris *mpam_get_or_create_ris(struct mpam_msc *msc, 
	return ERR_PTR(-ENOENT);

}



/*

 * IHI009A.a has this nugget: "If a monitor does not support automatic behaviour

 * of NRDY, software can use this bit for any purpose" - so hardware might not

 * implement this - but it isn't RES0.

 *

 * Try and see what values stick in this bit. If we can write either value,

 * its probably not implemented by hardware.

 */

static bool _mpam_ris_hw_probe_hw_nrdy(struct mpam_msc_ris *ris, u32 mon_reg)

{

	u32 now;

	u64 mon_sel;

	bool can_set, can_clear;

	struct mpam_msc *msc = ris->vmsc->msc;



	if (WARN_ON_ONCE(!mpam_mon_sel_lock(msc)))

		return false;



	mon_sel = FIELD_PREP(MSMON_CFG_MON_SEL_MON_SEL, 0) |

		  FIELD_PREP(MSMON_CFG_MON_SEL_RIS, ris->ris_idx);

	_mpam_write_monsel_reg(msc, mon_reg, mon_sel);



	_mpam_write_monsel_reg(msc, mon_reg, MSMON___NRDY);

	now = _mpam_read_monsel_reg(msc, mon_reg);

	can_set = now & MSMON___NRDY;



	_mpam_write_monsel_reg(msc, mon_reg, 0);

	now = _mpam_read_monsel_reg(msc, mon_reg);

	can_clear = !(now & MSMON___NRDY);

	mpam_mon_sel_unlock(msc);



	return (!can_set || !can_clear);

}



#define mpam_ris_hw_probe_hw_nrdy(_ris, _mon_reg)			\

	_mpam_ris_hw_probe_hw_nrdy(_ris, MSMON_##_mon_reg)



static void mpam_ris_hw_probe(struct mpam_msc_ris *ris)

{

	int err;

	struct mpam_msc *msc = ris->vmsc->msc;

	struct device *dev = &msc->pdev->dev;

	struct mpam_props *props = &ris->props;



	lockdep_assert_held(&msc->probe_lock);

	lockdep_assert_held(&msc->part_sel_lock);



	/* Cache Portion partitioning */

	if (FIELD_GET(MPAMF_IDR_HAS_CPOR_PART, ris->idr)) {

		u32 cpor_features = mpam_read_partsel_reg(msc, CPOR_IDR);



		props->cpbm_wd = FIELD_GET(MPAMF_CPOR_IDR_CPBM_WD, cpor_features);

		if (props->cpbm_wd)

			mpam_set_feature(mpam_feat_cpor_part, props);

	}



	/* Memory bandwidth partitioning */

	if (FIELD_GET(MPAMF_IDR_HAS_MBW_PART, ris->idr)) {

		u32 mbw_features = mpam_read_partsel_reg(msc, MBW_IDR);



		/* portion bitmap resolution */

		props->mbw_pbm_bits = FIELD_GET(MPAMF_MBW_IDR_BWPBM_WD, mbw_features);

		if (props->mbw_pbm_bits &&

		    FIELD_GET(MPAMF_MBW_IDR_HAS_PBM, mbw_features))

			mpam_set_feature(mpam_feat_mbw_part, props);



		props->bwa_wd = FIELD_GET(MPAMF_MBW_IDR_BWA_WD, mbw_features);

		if (props->bwa_wd && FIELD_GET(MPAMF_MBW_IDR_HAS_MAX, mbw_features))

			mpam_set_feature(mpam_feat_mbw_max, props);

	}



	/* Performance Monitoring */

	if (FIELD_GET(MPAMF_IDR_HAS_MSMON, ris->idr)) {

		u32 msmon_features = mpam_read_partsel_reg(msc, MSMON_IDR);



		/*

		 * If the firmware max-nrdy-us property is missing, the

		 * CSU counters can't be used. Should we wait forever?

		 */

		err = device_property_read_u32(&msc->pdev->dev,

					       "arm,not-ready-us",

					       &msc->nrdy_usec);



		if (FIELD_GET(MPAMF_MSMON_IDR_MSMON_CSU, msmon_features)) {

			u32 csumonidr;



			csumonidr = mpam_read_partsel_reg(msc, CSUMON_IDR);

			props->num_csu_mon = FIELD_GET(MPAMF_CSUMON_IDR_NUM_MON, csumonidr);

			if (props->num_csu_mon) {

				bool hw_managed;



				mpam_set_feature(mpam_feat_msmon_csu, props);



				/* Is NRDY hardware managed? */

				hw_managed = mpam_ris_hw_probe_hw_nrdy(ris, CSU);

				if (hw_managed)

					mpam_set_feature(mpam_feat_msmon_csu_hw_nrdy, props);

			}



			/*

			 * Accept the missing firmware property if NRDY appears

			 * un-implemented.

			 */

			if (err && mpam_has_feature(mpam_feat_msmon_csu_hw_nrdy, props))

				dev_err_once(dev, "Counters are not usable because not-ready timeout was not provided by firmware.");

		}

		if (FIELD_GET(MPAMF_MSMON_IDR_MSMON_MBWU, msmon_features)) {

			bool hw_managed;

			u32 mbwumon_idr = mpam_read_partsel_reg(msc, MBWUMON_IDR);



			props->num_mbwu_mon = FIELD_GET(MPAMF_MBWUMON_IDR_NUM_MON, mbwumon_idr);

			if (props->num_mbwu_mon)

				mpam_set_feature(mpam_feat_msmon_mbwu, props);



			/* Is NRDY hardware managed? */

			hw_managed = mpam_ris_hw_probe_hw_nrdy(ris, MBWU);

			if (hw_managed)

				mpam_set_feature(mpam_feat_msmon_mbwu_hw_nrdy, props);



			/*

			 * Don't warn about any missing firmware property for

			 * MBWU NRDY - it doesn't make any sense!

			 */

		}

	}

}



static int mpam_msc_hw_probe(struct mpam_msc *msc)

{

	u64 idr;
@@ -591,6 +734,12 @@ static int mpam_msc_hw_probe(struct mpam_msc *msc) 
		mutex_unlock(&mpam_list_lock);

		if (IS_ERR(ris))

			return PTR_ERR(ris);

		ris->idr = idr;



		mutex_lock(&msc->part_sel_lock);

		__mpam_part_sel(ris_idx, 0, msc);

		mpam_ris_hw_probe(ris);

		mutex_unlock(&msc->part_sel_lock);

	}



	spin_lock(&partid_max_lock);

drivers/resctrl/mpam_internal.h

+33 −0
Original line number Diff line number Diff line
@@ -5,12 +5,14 @@ 
#define MPAM_INTERNAL_H



#include <linux/arm_mpam.h>

#include <linux/bitmap.h>

#include <linux/cpumask.h>

#include <linux/io.h>

#include <linux/llist.h>

#include <linux/mutex.h>

#include <linux/srcu.h>

#include <linux/spinlock.h>

#include <linux/srcu.h>

#include <linux/types.h>



#define MPAM_MSC_MAX_NUM_RIS	16
@@ -112,6 +114,33 @@ static inline void mpam_mon_sel_lock_init(struct mpam_msc *msc) 
	raw_spin_lock_init(&msc->_mon_sel_lock);

}



/* Bits for mpam features bitmaps */

enum mpam_device_features {

	mpam_feat_cpor_part,

	mpam_feat_mbw_part,

	mpam_feat_mbw_min,

	mpam_feat_mbw_max,

	mpam_feat_msmon,

	mpam_feat_msmon_csu,

	mpam_feat_msmon_csu_hw_nrdy,

	mpam_feat_msmon_mbwu,

	mpam_feat_msmon_mbwu_hw_nrdy,

	MPAM_FEATURE_LAST

};



struct mpam_props {

	DECLARE_BITMAP(features, MPAM_FEATURE_LAST);



	u16			cpbm_wd;

	u16			mbw_pbm_bits;

	u16			bwa_wd;

	u16			num_csu_mon;

	u16			num_mbwu_mon;

};



#define mpam_has_feature(_feat, x)	test_bit(_feat, (x)->features)

#define mpam_set_feature(_feat, x)	set_bit(_feat, (x)->features)



struct mpam_class {

	/* mpam_components in this class */

	struct list_head	components;
@@ -151,6 +180,8 @@ struct mpam_vmsc { 
	/* mpam_msc_ris in this vmsc */

	struct list_head	ris;



	struct mpam_props	props;



	/* All RIS in this vMSC are members of this MSC */

	struct mpam_msc		*msc;
@@ -162,6 +193,8 @@ struct mpam_vmsc { 


struct mpam_msc_ris {

	u8			ris_idx;

	u64			idr;

	struct mpam_props	props;



	cpumask_t		affinity;