arm_mpam: propagate MSC access errors for hw_probe functions

Allow the functions probing for MSC hardware and features to return an
error, and propagate read and write errors from the lower level up.
This uses some "scoped cleanup" functions like scoped_guard() and
ACQUIRE() to avoid the complexity of error handling when a lock has been
taken. Since the mon_sel_lock is a bit special (even more so in an
upcoming patch), we define a new GUARD type for it.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Jonathan Cameron <jonathan.cameron@oss.qualcomm.com>
Reviewed-by: Ben Horgan <ben.horgan@arm.com>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Tested-by: Gavin Shan <gshan@redhat.com> # on NVIDIA Grace Hopper
Signed-off-by: James Morse <james.morse@arm.com>
This commit is contained in:
Andre Przywara 2026-10-01 17:34:27 +02:00 committed by James Morse
parent 84e8795c27
commit 0db1715e4c
2 changed files with 103 additions and 46 deletions

View File

@ -792,44 +792,62 @@ static void mpam_enable_quirks(struct mpam_msc *msc)
* Try and see what values stick in this bit. If we can write either value, * Try and see what values stick in this bit. If we can write either value,
* its probably not implemented by hardware. * its probably not implemented by hardware.
*/ */
static bool mpam_ris_hw_probe_csu_nrdy(struct mpam_msc_ris *ris) static int mpam_ris_hw_probe_csu_nrdy(struct mpam_msc_ris *ris)
{ {
u32 now, mon_sel, ctl_val; u32 now, mon_sel, ctl_val;
bool can_set, can_clear; bool can_set, can_clear;
struct mpam_msc *msc = ris->vmsc->msc; struct mpam_msc *msc = ris->vmsc->msc;
int ret;
if (WARN_ON_ONCE(!mpam_mon_sel_lock(msc))) ACQUIRE(mon_sel_lock, guard)(msc);
return false; ret = ACQUIRE_ERR(mon_sel_lock, &guard);
if (ret)
return ret;
mon_sel = FIELD_PREP(MSMON_CFG_MON_SEL_MON_SEL, 0) | mon_sel = FIELD_PREP(MSMON_CFG_MON_SEL_MON_SEL, 0) |
FIELD_PREP(MSMON_CFG_MON_SEL_RIS, ris->ris_idx); FIELD_PREP(MSMON_CFG_MON_SEL_RIS, ris->ris_idx);
mpam_write_monsel_reg(msc, CFG_MON_SEL, mon_sel); ret = mpam_write_monsel_reg(msc, CFG_MON_SEL, mon_sel);
if (ret)
return ret;
/* Hardware might ignore nrdy if it's not enabled */ /* Hardware might ignore nrdy if it's not enabled */
ctl_val = MSMON_CFG_CSU_CTL_TYPE_CSU; ctl_val = MSMON_CFG_CSU_CTL_TYPE_CSU;
ctl_val |= MSMON_CFG_x_CTL_MATCH_PARTID; ctl_val |= MSMON_CFG_x_CTL_MATCH_PARTID;
ctl_val |= MSMON_CFG_x_CTL_MATCH_PMG; ctl_val |= MSMON_CFG_x_CTL_MATCH_PMG;
ctl_val |= MSMON_CFG_x_CTL_EN; ctl_val |= MSMON_CFG_x_CTL_EN;
mpam_write_monsel_reg(msc, CFG_CSU_FLT, 0); ret = mpam_write_monsel_reg(msc, CFG_CSU_FLT, 0);
mpam_write_monsel_reg(msc, CFG_CSU_CTL, ctl_val); if (ret)
return ret;
ret = mpam_write_monsel_reg(msc, CFG_CSU_CTL, ctl_val);
if (ret)
return ret;
_mpam_write_monsel_reg(msc, MSMON_CSU, MSMON___NRDY); ret = _mpam_write_monsel_reg(msc, MSMON_CSU, MSMON___NRDY);
_mpam_read_monsel_reg(msc, MSMON_CSU, &now); if (ret)
return ret;
ret = _mpam_read_monsel_reg(msc, MSMON_CSU, &now);
if (ret)
return ret;
can_set = now & MSMON___NRDY; can_set = now & MSMON___NRDY;
_mpam_write_monsel_reg(msc, MSMON_CSU, 0); ret = _mpam_write_monsel_reg(msc, MSMON_CSU, 0);
if (ret)
return ret;
/* Configuration change to try and coax hardware into setting nrdy */ /* Configuration change to try and coax hardware into setting nrdy */
mpam_write_monsel_reg(msc, CFG_CSU_FLT, 0x1); ret = mpam_write_monsel_reg(msc, CFG_CSU_FLT, 0x1);
_mpam_read_monsel_reg(msc, MSMON_CSU, &now); if (ret)
return ret;
ret = _mpam_read_monsel_reg(msc, MSMON_CSU, &now);
if (ret)
return ret;
can_clear = !(now & MSMON___NRDY); can_clear = !(now & MSMON___NRDY);
mpam_mon_sel_unlock(msc);
return (!can_set || !can_clear); return (!can_set || !can_clear);
} }
static void mpam_ris_hw_probe(struct mpam_msc_ris *ris) static int mpam_ris_hw_probe(struct mpam_msc_ris *ris)
{ {
int err; int fw_has_nrdy_err, err;
struct mpam_msc *msc = ris->vmsc->msc; struct mpam_msc *msc = ris->vmsc->msc;
struct device *dev = &msc->pdev->dev; struct device *dev = &msc->pdev->dev;
struct mpam_props *props = &ris->props; struct mpam_props *props = &ris->props;
@ -842,7 +860,9 @@ static void mpam_ris_hw_probe(struct mpam_msc_ris *ris)
if (FIELD_GET(MPAMF_IDR_HAS_CCAP_PART, ris->idr)) { if (FIELD_GET(MPAMF_IDR_HAS_CCAP_PART, ris->idr)) {
u32 ccap_features; u32 ccap_features;
mpam_read_partsel_reg(msc, CCAP_IDR, &ccap_features); err = mpam_read_partsel_reg(msc, CCAP_IDR, &ccap_features);
if (err)
return err;
props->cmax_wd = FIELD_GET(MPAMF_CCAP_IDR_CMAX_WD, ccap_features); props->cmax_wd = FIELD_GET(MPAMF_CCAP_IDR_CMAX_WD, ccap_features);
if (props->cmax_wd && if (props->cmax_wd &&
@ -867,7 +887,9 @@ static void mpam_ris_hw_probe(struct mpam_msc_ris *ris)
if (FIELD_GET(MPAMF_IDR_HAS_CPOR_PART, ris->idr)) { if (FIELD_GET(MPAMF_IDR_HAS_CPOR_PART, ris->idr)) {
u32 cpor_features; u32 cpor_features;
mpam_read_partsel_reg(msc, CPOR_IDR, &cpor_features); err = mpam_read_partsel_reg(msc, CPOR_IDR, &cpor_features);
if (err)
return err;
props->cpbm_wd = FIELD_GET(MPAMF_CPOR_IDR_CPBM_WD, cpor_features); props->cpbm_wd = FIELD_GET(MPAMF_CPOR_IDR_CPBM_WD, cpor_features);
if (props->cpbm_wd) if (props->cpbm_wd)
@ -877,8 +899,9 @@ static void mpam_ris_hw_probe(struct mpam_msc_ris *ris)
/* Memory bandwidth partitioning */ /* Memory bandwidth partitioning */
if (FIELD_GET(MPAMF_IDR_HAS_MBW_PART, ris->idr)) { if (FIELD_GET(MPAMF_IDR_HAS_MBW_PART, ris->idr)) {
u32 mbw_features; u32 mbw_features;
err = mpam_read_partsel_reg(msc, MBW_IDR, &mbw_features);
mpam_read_partsel_reg(msc, MBW_IDR, &mbw_features); if (err)
return err;
/* portion bitmap resolution */ /* portion bitmap resolution */
props->mbw_pbm_bits = FIELD_GET(MPAMF_MBW_IDR_BWPBM_WD, mbw_features); props->mbw_pbm_bits = FIELD_GET(MPAMF_MBW_IDR_BWPBM_WD, mbw_features);
@ -907,8 +930,9 @@ static void mpam_ris_hw_probe(struct mpam_msc_ris *ris)
/* Priority partitioning */ /* Priority partitioning */
if (FIELD_GET(MPAMF_IDR_HAS_PRI_PART, ris->idr)) { if (FIELD_GET(MPAMF_IDR_HAS_PRI_PART, ris->idr)) {
u32 pri_features; u32 pri_features;
err = mpam_read_partsel_reg(msc, PRI_IDR, &pri_features);
mpam_read_partsel_reg(msc, PRI_IDR, &pri_features); if (err)
return err;
props->intpri_wd = FIELD_GET(MPAMF_PRI_IDR_INTPRI_WD, pri_features); props->intpri_wd = FIELD_GET(MPAMF_PRI_IDR_INTPRI_WD, pri_features);
if (props->intpri_wd && FIELD_GET(MPAMF_PRI_IDR_HAS_INTPRI, pri_features)) { if (props->intpri_wd && FIELD_GET(MPAMF_PRI_IDR_HAS_INTPRI, pri_features)) {
@ -929,20 +953,24 @@ static void mpam_ris_hw_probe(struct mpam_msc_ris *ris)
if (FIELD_GET(MPAMF_IDR_HAS_MSMON, ris->idr)) { if (FIELD_GET(MPAMF_IDR_HAS_MSMON, ris->idr)) {
u32 msmon_features; u32 msmon_features;
mpam_read_partsel_reg(msc, MSMON_IDR, &msmon_features); err = mpam_read_partsel_reg(msc, MSMON_IDR, &msmon_features);
if (err)
return err;
/* /*
* If the firmware max-nrdy-us property is missing, the * If the firmware max-nrdy-us property is missing, the
* CSU counters can't be used. Should we wait forever? * CSU counters can't be used. Should we wait forever?
*/ */
err = device_property_read_u32(&msc->pdev->dev, fw_has_nrdy_err = device_property_read_u32(&msc->pdev->dev,
"arm,not-ready-us", "arm,not-ready-us",
&msc->nrdy_usec); &msc->nrdy_usec);
if (FIELD_GET(MPAMF_MSMON_IDR_MSMON_CSU, msmon_features)) { if (FIELD_GET(MPAMF_MSMON_IDR_MSMON_CSU, msmon_features)) {
u32 csumonidr; u32 csumonidr;
mpam_read_partsel_reg(msc, CSUMON_IDR, &csumonidr); err = mpam_read_partsel_reg(msc, CSUMON_IDR, &csumonidr);
if (err)
return err;
props->num_csu_mon = FIELD_GET(MPAMF_CSUMON_IDR_NUM_MON, csumonidr); props->num_csu_mon = FIELD_GET(MPAMF_CSUMON_IDR_NUM_MON, csumonidr);
if (props->num_csu_mon) { if (props->num_csu_mon) {
@ -954,13 +982,16 @@ static void mpam_ris_hw_probe(struct mpam_msc_ris *ris)
mpam_set_feature(mpam_feat_msmon_csu_xcl, props); mpam_set_feature(mpam_feat_msmon_csu_xcl, props);
/* Is NRDY hardware managed? */ /* Is NRDY hardware managed? */
hw_managed = mpam_ris_hw_probe_csu_nrdy(ris); err = mpam_ris_hw_probe_csu_nrdy(ris);
if (err < 0)
return err;
hw_managed = err;
/* /*
* Accept the missing firmware property if NRDY appears * Accept the missing firmware property if NRDY appears
* un-implemented. * un-implemented.
*/ */
if (err && hw_managed) if (fw_has_nrdy_err && hw_managed)
dev_err_once(dev, "Counters are not usable because not-ready timeout was not provided by firmware."); dev_err_once(dev, "Counters are not usable because not-ready timeout was not provided by firmware.");
} }
} }
@ -968,7 +999,9 @@ static void mpam_ris_hw_probe(struct mpam_msc_ris *ris)
bool has_long; bool has_long;
u32 mbwumon_idr; u32 mbwumon_idr;
mpam_read_partsel_reg(msc, MBWUMON_IDR, &mbwumon_idr); err = mpam_read_partsel_reg(msc, MBWUMON_IDR, &mbwumon_idr);
if (err)
return err;
props->num_mbwu_mon = FIELD_GET(MPAMF_MBWUMON_IDR_NUM_MON, mbwumon_idr); props->num_mbwu_mon = FIELD_GET(MPAMF_MBWUMON_IDR_NUM_MON, mbwumon_idr);
if (props->num_mbwu_mon) { if (props->num_mbwu_mon) {
@ -1001,16 +1034,22 @@ static void mpam_ris_hw_probe(struct mpam_msc_ris *ris)
u16 partid_max; u16 partid_max;
u32 nrwidr; u32 nrwidr;
mpam_read_partsel_reg(msc, PARTID_NRW_IDR, &nrwidr); err = mpam_read_partsel_reg(msc, PARTID_NRW_IDR, &nrwidr);
if (err)
return err;
partid_max = FIELD_GET(MPAMF_PARTID_NRW_IDR_INTPARTID_MAX, nrwidr); partid_max = FIELD_GET(MPAMF_PARTID_NRW_IDR_INTPARTID_MAX, nrwidr);
mpam_set_feature(mpam_feat_partid_nrw, props); mpam_set_feature(mpam_feat_partid_nrw, props);
msc->partid_max = min(msc->partid_max, partid_max); msc->partid_max = min(msc->partid_max, partid_max);
} }
return 0;
} }
static int mpam_msc_hw_probe(struct mpam_msc *msc) static int mpam_msc_hw_probe(struct mpam_msc *msc)
{ {
int ret;
u64 idr; u64 idr;
u16 partid_max; u16 partid_max;
u8 ris_idx, pmg_max; u8 ris_idx, pmg_max;
@ -1025,11 +1064,15 @@ static int mpam_msc_hw_probe(struct mpam_msc *msc)
} }
/* Grab an IDR value to find out how many RIS there are */ /* Grab an IDR value to find out how many RIS there are */
mutex_lock(&msc->part_sel_lock); scoped_guard(mutex, &msc->part_sel_lock) {
mpam_msc_read_idr(msc, &idr); ret = mpam_msc_read_idr(msc, &idr);
mpam_read_partsel_reg(msc, IIDR, &msc->iidr); if (ret)
return ret;
mutex_unlock(&msc->part_sel_lock); ret = mpam_read_partsel_reg(msc, IIDR, &msc->iidr);
if (ret)
return ret;
}
mpam_enable_quirks(msc); mpam_enable_quirks(msc);
@ -1040,10 +1083,15 @@ static int mpam_msc_hw_probe(struct mpam_msc *msc)
msc->pmg_max = FIELD_GET(MPAMF_IDR_PMG_MAX, idr); msc->pmg_max = FIELD_GET(MPAMF_IDR_PMG_MAX, idr);
for (ris_idx = 0; ris_idx <= msc->ris_max; ris_idx++) { for (ris_idx = 0; ris_idx <= msc->ris_max; ris_idx++) {
mutex_lock(&msc->part_sel_lock); scoped_guard(mutex, &msc->part_sel_lock) {
__mpam_part_sel(ris_idx, 0, msc); ret = __mpam_part_sel(ris_idx, 0, msc);
mpam_msc_read_idr(msc, &idr); if (ret)
mutex_unlock(&msc->part_sel_lock); return ret;
ret = mpam_msc_read_idr(msc, &idr);
if (ret)
return ret;
}
partid_max = FIELD_GET(MPAMF_IDR_PARTID_MAX, idr); partid_max = FIELD_GET(MPAMF_IDR_PARTID_MAX, idr);
pmg_max = FIELD_GET(MPAMF_IDR_PMG_MAX, idr); pmg_max = FIELD_GET(MPAMF_IDR_PMG_MAX, idr);
@ -1051,17 +1099,22 @@ static int mpam_msc_hw_probe(struct mpam_msc *msc)
msc->pmg_max = min(msc->pmg_max, pmg_max); msc->pmg_max = min(msc->pmg_max, pmg_max);
msc->has_extd_esr = FIELD_GET(MPAMF_IDR_HAS_EXTD_ESR, idr); msc->has_extd_esr = FIELD_GET(MPAMF_IDR_HAS_EXTD_ESR, idr);
mutex_lock(&mpam_list_lock); scoped_guard(mutex, &mpam_list_lock) {
ris = mpam_get_or_create_ris(msc, ris_idx); ris = mpam_get_or_create_ris(msc, ris_idx);
mutex_unlock(&mpam_list_lock); if (IS_ERR(ris))
if (IS_ERR(ris)) return PTR_ERR(ris);
return PTR_ERR(ris); }
ris->idr = idr; ris->idr = idr;
mutex_lock(&msc->part_sel_lock); scoped_guard(mutex, &msc->part_sel_lock) {
__mpam_part_sel(ris_idx, 0, msc); ret = __mpam_part_sel(ris_idx, 0, msc);
mpam_ris_hw_probe(ris); if (ret)
mutex_unlock(&msc->part_sel_lock); return ret;
ret = mpam_ris_hw_probe(ris);
if (ret)
return ret;
}
} }
/* Clear any stale errors */ /* Clear any stale errors */

View File

@ -162,6 +162,10 @@ static inline void mpam_mon_sel_lock_init(struct mpam_msc *msc)
raw_spin_lock_init(&msc->_mon_sel_lock); raw_spin_lock_init(&msc->_mon_sel_lock);
} }
DEFINE_GUARD(mon_sel, struct mpam_msc *,
mpam_mon_sel_lock(_T), mpam_mon_sel_unlock(_T));
DEFINE_GUARD_COND(mon_sel, _lock, mpam_mon_sel_lock(_T), _RET);
/* Bits for mpam features bitmaps */ /* Bits for mpam features bitmaps */
enum mpam_device_features { enum mpam_device_features {
mpam_feat_cpor_part, mpam_feat_cpor_part,