From 797d3186544fcd5bfd7a03b9ef3e20c1db3802b8 Mon Sep 17 00:00:00 2001 From: Vincent Cheng Date: Wed, 17 Feb 2021 00:42:12 -0500 Subject: ptp: ptp_clockmatrix: Add wait_for_sys_apll_dpll_lock. Part of the device initialization aligns the rising edge of the output clock to the internal 1 PPS clock. If the system APLL and DPLL is not locked, then the alignment will fail and there will be a fixed offset between the internal 1 PPS clock and the output clock. After loading the device firmware, poll the system APLL and DPLL for locked state prior to initialization, timing out after 2 seconds. Signed-off-by: Vincent Cheng Acked-by: Richard Cochran Signed-off-by: David S. Miller --- drivers/ptp/ptp_clockmatrix.c | 64 +++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 62 insertions(+), 2 deletions(-) (limited to 'drivers/ptp/ptp_clockmatrix.c') diff --git a/drivers/ptp/ptp_clockmatrix.c b/drivers/ptp/ptp_clockmatrix.c index 051511f5e1f2..9bfd32baad92 100644 --- a/drivers/ptp/ptp_clockmatrix.c +++ b/drivers/ptp/ptp_clockmatrix.c @@ -335,6 +335,67 @@ static int wait_for_boot_status_ready(struct idtcm *idtcm) return -EBUSY; } +static int read_sys_apll_status(struct idtcm *idtcm, u8 *status) +{ + return idtcm_read(idtcm, STATUS, DPLL_SYS_APLL_STATUS, status, + sizeof(u8)); +} + +static int read_sys_dpll_status(struct idtcm *idtcm, u8 *status) +{ + return idtcm_read(idtcm, STATUS, DPLL_SYS_STATUS, status, sizeof(u8)); +} + +static int wait_for_sys_apll_dpll_lock(struct idtcm *idtcm) +{ + unsigned long timeout = jiffies + msecs_to_jiffies(LOCK_TIMEOUT_MS); + u8 apll = 0; + u8 dpll = 0; + int err; + + do { + err = read_sys_apll_status(idtcm, &apll); + if (err) + return err; + + err = read_sys_dpll_status(idtcm, &dpll); + if (err) + return err; + + apll &= SYS_APLL_LOSS_LOCK_LIVE_MASK; + dpll &= DPLL_SYS_STATE_MASK; + + if (apll == SYS_APLL_LOSS_LOCK_LIVE_LOCKED && + dpll == DPLL_STATE_LOCKED) { + return 0; + } else if (dpll == DPLL_STATE_FREERUN || + dpll == DPLL_STATE_HOLDOVER || + dpll == DPLL_STATE_OPEN_LOOP) { + dev_warn(&idtcm->client->dev, + "No wait state: DPLL_SYS_STATE %d", dpll); + return -EPERM; + } + + msleep(LOCK_POLL_INTERVAL_MS); + } while (time_is_after_jiffies(timeout)); + + dev_warn(&idtcm->client->dev, + "%d ms lock timeout: SYS APLL Loss Lock %d SYS DPLL state %d", + LOCK_TIMEOUT_MS, apll, dpll); + + return -ETIME; +} + +static void wait_for_chip_ready(struct idtcm *idtcm) +{ + if (wait_for_boot_status_ready(idtcm)) + dev_warn(&idtcm->client->dev, "BOOT_STATUS != 0xA0"); + + if (wait_for_sys_apll_dpll_lock(idtcm)) + dev_warn(&idtcm->client->dev, + "Continuing while SYS APLL/DPLL is not locked"); +} + static int _idtcm_gettime(struct idtcm_channel *channel, struct timespec64 *ts) { @@ -2235,8 +2296,7 @@ static int idtcm_probe(struct i2c_client *client, dev_warn(&idtcm->client->dev, "loading firmware failed with %d\n", err); - if (wait_for_boot_status_ready(idtcm)) - dev_warn(&idtcm->client->dev, "BOOT_STATUS != 0xA0\n"); + wait_for_chip_ready(idtcm); if (idtcm->tod_mask) { for (i = 0; i < MAX_TOD; i++) { -- cgit v1.2.3