bnxt_en: add unlocked version of bnxt_refclk_read

Serialization of PHC read with FW reset mechanism uses ptp_lock which
also protects timecounter updates. This means we cannot grab it when
called from bnxt_cc_read(). Let's move locking into different function.

Fixes: 6c0828d00f ("bnxt_en: replace PTP spinlock with seqlock")
Signed-off-by: Vadim Fedorenko <vadfed@meta.com>
Reviewed-by: Pavan Chebbi <pavan.chebbi@broadcom.com>
Link: https://patch.msgid.link/20241107214917.2980976-1-vadfed@meta.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Vadim Fedorenko 2024-11-07 13:49:17 -08:00 committed by Jakub Kicinski
parent 5ffb7ac02d
commit f0fe51a043

View File

@ -73,19 +73,15 @@ static int bnxt_ptp_settime(struct ptp_clock_info *ptp_info,
return 0;
}
static int bnxt_refclk_read(struct bnxt *bp, struct ptp_system_timestamp *sts,
u64 *ns)
/* Caller holds ptp_lock */
static int __bnxt_refclk_read(struct bnxt *bp, struct ptp_system_timestamp *sts,
u64 *ns)
{
struct bnxt_ptp_cfg *ptp = bp->ptp_cfg;
u32 high_before, high_now, low;
unsigned long flags;
/* We have to serialize reg access and FW reset */
read_seqlock_excl_irqsave(&ptp->ptp_lock, flags);
if (test_bit(BNXT_STATE_IN_FW_RESET, &bp->state)) {
read_sequnlock_excl_irqrestore(&ptp->ptp_lock, flags);
if (test_bit(BNXT_STATE_IN_FW_RESET, &bp->state))
return -EIO;
}
high_before = readl(bp->bar0 + ptp->refclk_mapped_regs[1]);
ptp_read_system_prets(sts);
@ -97,12 +93,25 @@ static int bnxt_refclk_read(struct bnxt *bp, struct ptp_system_timestamp *sts,
low = readl(bp->bar0 + ptp->refclk_mapped_regs[0]);
ptp_read_system_postts(sts);
}
read_sequnlock_excl_irqrestore(&ptp->ptp_lock, flags);
*ns = ((u64)high_now << 32) | low;
return 0;
}
static int bnxt_refclk_read(struct bnxt *bp, struct ptp_system_timestamp *sts,
u64 *ns)
{
struct bnxt_ptp_cfg *ptp = bp->ptp_cfg;
unsigned long flags;
int rc;
/* We have to serialize reg access and FW reset */
read_seqlock_excl_irqsave(&ptp->ptp_lock, flags);
rc = __bnxt_refclk_read(bp, sts, ns);
read_sequnlock_excl_irqrestore(&ptp->ptp_lock, flags);
return rc;
}
static void bnxt_ptp_get_current_time(struct bnxt *bp)
{
struct bnxt_ptp_cfg *ptp = bp->ptp_cfg;
@ -674,7 +683,7 @@ static u64 bnxt_cc_read(const struct cyclecounter *cc)
struct bnxt_ptp_cfg *ptp = container_of(cc, struct bnxt_ptp_cfg, cc);
u64 ns = 0;
bnxt_refclk_read(ptp->bp, NULL, &ns);
__bnxt_refclk_read(ptp->bp, NULL, &ns);
return ns;
}
@ -936,6 +945,7 @@ static bool bnxt_pps_config_ok(struct bnxt *bp)
static void bnxt_ptp_timecounter_init(struct bnxt *bp, bool init_tc)
{
struct bnxt_ptp_cfg *ptp = bp->ptp_cfg;
unsigned long flags;
if (!ptp->ptp_clock) {
memset(&ptp->cc, 0, sizeof(ptp->cc));
@ -952,8 +962,11 @@ static void bnxt_ptp_timecounter_init(struct bnxt *bp, bool init_tc)
}
ptp->next_overflow_check = jiffies + BNXT_PHC_OVERFLOW_PERIOD;
}
if (init_tc)
if (init_tc) {
write_seqlock_irqsave(&ptp->ptp_lock, flags);
timecounter_init(&ptp->tc, &ptp->cc, ktime_to_ns(ktime_get_real()));
write_sequnlock_irqrestore(&ptp->ptp_lock, flags);
}
}
/* Caller holds ptp_lock */