Commit 36343a8f authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux 

Pull arm64 MPAM fixes from Catalin Marinas:

 - Fix NULL dereference and a false-positive warning when the driver
   probes hardware with surprising version numbers

 - Fix writing values to the wrong registers when probing
   cache-utilisation counters. Replace 'NRDY' probing with a version
   that is robust for platforms where the bit is writeable by both
   hardware and software

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm_mpam: Check whether the config array is allocated before destroying it
  arm_mpam: Fix false positive assert failure during mpam_disable()
  arm_mpam: Improve check for whether or not NRDY is hardware managed
  arm_mpam: Pretend that NRDY is always hardware managed
  arm_mpam: Fix monitor instance selection when checking for hardware NRDY
parents 30e0ff6d 6ccbb613

drivers/resctrl/mpam_devices.c

+40 −41
Original line number Diff line number Diff line
@@ -164,10 +164,16 @@ static void mpam_free_garbage(void) 
/*

 * Once mpam is enabled, new requestors cannot further reduce the available

 * partid. Assert that the size is fixed, and new requestors will be turned

 * away.

 * away. This is needed when walking over structures sized by PARTID.

 *

 * During mpam_disable() these structures are not fixed, but the MSC state

 * is still reset using whatever sizes have been discovered so far. As only

 * PARTID 0 will be used after mpam_disable(), any race would be benign.

 * Skip the check if a mpam_disable_reason has been set.

 */

static void mpam_assert_partid_sizes_fixed(void)

{

	if (!mpam_disable_reason)

		WARN_ON_ONCE(!partid_max_published);

}
@@ -728,10 +734,9 @@ static void mpam_enable_quirks(struct mpam_msc *msc) 
 * 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)

static bool mpam_ris_hw_probe_csu_nrdy(struct mpam_msc_ris *ris)

{

	u32 now;

	u64 mon_sel;

	u32 now, mon_sel, ctl_val;

	bool can_set, can_clear;

	struct mpam_msc *msc = ris->vmsc->msc;
@@ -740,23 +745,30 @@ static bool _mpam_ris_hw_probe_hw_nrdy(struct mpam_msc_ris *ris, u32 mon_reg) 


	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, CFG_MON_SEL, mon_sel);



	/* Hardware might ignore nrdy if it's not enabled */

	ctl_val = MSMON_CFG_CSU_CTL_TYPE_CSU;

	ctl_val |= MSMON_CFG_x_CTL_MATCH_PARTID;

	ctl_val |= MSMON_CFG_x_CTL_MATCH_PMG;

	ctl_val |= MSMON_CFG_x_CTL_EN;

	mpam_write_monsel_reg(msc, CFG_CSU_FLT, 0);

	mpam_write_monsel_reg(msc, CFG_CSU_CTL, ctl_val);



	_mpam_write_monsel_reg(msc, mon_reg, MSMON___NRDY);

	now = _mpam_read_monsel_reg(msc, mon_reg);

	_mpam_write_monsel_reg(msc, MSMON_CSU, MSMON___NRDY);

	now = _mpam_read_monsel_reg(msc, MSMON_CSU);

	can_set = now & MSMON___NRDY;



	_mpam_write_monsel_reg(msc, mon_reg, 0);

	now = _mpam_read_monsel_reg(msc, mon_reg);

	_mpam_write_monsel_reg(msc, MSMON_CSU, 0);

	/* Configuration change to try and coax hardware into setting nrdy */

	mpam_write_monsel_reg(msc, CFG_CSU_FLT, 0x1);

	now = _mpam_read_monsel_reg(msc, MSMON_CSU);

	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;
@@ -873,20 +885,18 @@ static void mpam_ris_hw_probe(struct mpam_msc_ris *ris) 
					mpam_set_feature(mpam_feat_msmon_csu_xcl, 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);

			}

				hw_managed = mpam_ris_hw_probe_csu_nrdy(ris);



				/*

				 * Accept the missing firmware property if NRDY appears

				 * un-implemented.

				 */

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

				if (err && hw_managed)

					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 has_long, hw_managed;

			bool has_long;

			u32 mbwumon_idr = mpam_read_partsel_reg(msc, MBWUMON_IDR);



			props->num_mbwu_mon = FIELD_GET(MPAMF_MBWUMON_IDR_NUM_MON, mbwumon_idr);
@@ -905,16 +915,6 @@ static void mpam_ris_hw_probe(struct mpam_msc_ris *ris) 
				} else {

					mpam_set_feature(mpam_feat_msmon_mbwu_31counter, 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!

				 */

			}

		}

	}
@@ -1197,7 +1197,6 @@ static void __ris_msmon_read(void *arg) 
	bool reset_on_next_read = false;

	struct mpam_msc_ris *ris = m->ris;

	struct msmon_mbwu_state *mbwu_state;

	struct mpam_props *rprops = &ris->props;

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

	u32 mon_sel, ctl_val, flt_val, cur_ctl, cur_flt;
@@ -1253,7 +1252,6 @@ static void __ris_msmon_read(void *arg) 
	switch (m->type) {

	case mpam_feat_msmon_csu:

		now = mpam_read_monsel_reg(msc, CSU);

		if (mpam_has_feature(mpam_feat_msmon_csu_hw_nrdy, rprops))

		nrdy = now & MSMON___NRDY;

		now = FIELD_GET(MSMON___VALUE, now);
@@ -1266,7 +1264,6 @@ static void __ris_msmon_read(void *arg) 
	case mpam_feat_msmon_mbwu_63counter:

		if (m->type != mpam_feat_msmon_mbwu_31counter) {

			now = mpam_msc_read_mbwu_l(msc);

			if (mpam_has_feature(mpam_feat_msmon_mbwu_hw_nrdy, rprops))

			nrdy = now & MSMON___L_NRDY;



			if (m->type == mpam_feat_msmon_mbwu_63counter)
@@ -1275,7 +1272,6 @@ static void __ris_msmon_read(void *arg) 
				now = FIELD_GET(MSMON___L_VALUE, now);

		} else {

			now = mpam_read_monsel_reg(msc, MBWU);

			if (mpam_has_feature(mpam_feat_msmon_mbwu_hw_nrdy, rprops))

			nrdy = now & MSMON___NRDY;

			now = FIELD_GET(MSMON___VALUE, now);

		}
@@ -2585,6 +2581,9 @@ static void __destroy_component_cfg(struct mpam_component *comp) 


	lockdep_assert_held(&mpam_list_lock);



	if (!comp->cfg)

		return;



	add_to_garbage(comp->cfg);

	list_for_each_entry(vmsc, &comp->vmsc, comp_list) {

		msc = vmsc->msc;

drivers/resctrl/mpam_internal.h

+0 −2
Original line number Diff line number Diff line
@@ -181,14 +181,12 @@ enum mpam_device_features { 
	mpam_feat_msmon_csu,

	mpam_feat_msmon_csu_capture,

	mpam_feat_msmon_csu_xcl,

	mpam_feat_msmon_csu_hw_nrdy,

	mpam_feat_msmon_mbwu,

	mpam_feat_msmon_mbwu_31counter,

	mpam_feat_msmon_mbwu_44counter,

	mpam_feat_msmon_mbwu_63counter,

	mpam_feat_msmon_mbwu_capture,

	mpam_feat_msmon_mbwu_rwbw,

	mpam_feat_msmon_mbwu_hw_nrdy,

	mpam_feat_partid_nrw,

	MPAM_FEATURE_LAST

};