[PATCH net v4 1/2] ptp: ptp_clockmatrix: Add PTP_CLK_REQ_EXTTS support

From: Min Li
Date: Wed May 04 2022 - 16:51:22 EST

Use TOD_READ_SECONDARY for extts to keep TOD_READ_PRIMARY
for gettime and settime exclusively

Signed-off-by: Min Li <min.li.xe@xxxxxxxxxxx>
Acked-by: Richard Cochran <richardcochran@xxxxxxxxx>
---
changelog
-use div helpers to do 64b division
-change comments to comply with kernel-doc format
-Fix Jakub comments

drivers/ptp/ptp_clockmatrix.c | 290 ++++++++++++++++++++++++---------------
drivers/ptp/ptp_clockmatrix.h | 5 +
include/linux/mfd/idt8a340_reg.h | 12 +-
3 files changed, 198 insertions(+), 109 deletions(-)

diff --git a/drivers/ptp/ptp_clockmatrix.c b/drivers/ptp/ptp_clockmatrix.c
index 08e429a..70791dc 100644
--- a/drivers/ptp/ptp_clockmatrix.c
+++ b/drivers/ptp/ptp_clockmatrix.c
@@ -239,73 +239,97 @@ static int wait_for_boot_status_ready(struct idtcm *idtcm)
return -EBUSY;
}

-static int _idtcm_set_scsr_read_trig(struct idtcm_channel *channel,
- enum scsr_read_trig_sel trig, u8 ref)
+static int arm_tod_read_trig_sel_refclk(struct idtcm_channel *channel, u8 ref)
{
struct idtcm *idtcm = channel->idtcm;
- u16 tod_read_cmd = IDTCM_FW_REG(idtcm->fw_ver, V520, TOD_READ_PRIMARY_CMD);
- u8 val;
+ u16 tod_read_cmd = IDTCM_FW_REG(idtcm->fw_ver, V520, TOD_READ_SECONDARY_CMD);
+ u8 val = 0;
int err;

- if (trig == SCSR_TOD_READ_TRIG_SEL_REFCLK) {
- err = idtcm_read(idtcm, channel->tod_read_primary,
- TOD_READ_PRIMARY_SEL_CFG_0, &val, sizeof(val));
- if (err)
- return err;
-
- val &= ~(WR_REF_INDEX_MASK << WR_REF_INDEX_SHIFT);
- val |= (ref << WR_REF_INDEX_SHIFT);
-
- err = idtcm_write(idtcm, channel->tod_read_primary,
- TOD_READ_PRIMARY_SEL_CFG_0, &val, sizeof(val));
- if (err)
- return err;
- }
+ val &= ~(WR_REF_INDEX_MASK << WR_REF_INDEX_SHIFT);
+ val |= (ref << WR_REF_INDEX_SHIFT);

- err = idtcm_read(idtcm, channel->tod_read_primary,
- tod_read_cmd, &val, sizeof(val));
+ err = idtcm_write(idtcm, channel->tod_read_secondary,
+ TOD_READ_SECONDARY_SEL_CFG_0, &val, sizeof(val));
if (err)
return err;

- val &= ~(TOD_READ_TRIGGER_MASK << TOD_READ_TRIGGER_SHIFT);
- val |= (trig << TOD_READ_TRIGGER_SHIFT);
- val &= ~TOD_READ_TRIGGER_MODE; /* single shot */
+ val = 0 | (SCSR_TOD_READ_TRIG_SEL_REFCLK << TOD_READ_TRIGGER_SHIFT);
+
+ err = idtcm_write(idtcm, channel->tod_read_secondary, tod_read_cmd,
+ &val, sizeof(val));
+ if (err)
+ dev_err(idtcm->dev, "%s: err = %d", __func__, err);

- err = idtcm_write(idtcm, channel->tod_read_primary,
- tod_read_cmd, &val, sizeof(val));
return err;
}

-static int idtcm_enable_extts(struct idtcm_channel *channel, u8 todn, u8 ref,
- bool enable)
+static bool is_single_shot(u8 mask)
{
- struct idtcm *idtcm = channel->idtcm;
- u8 old_mask = idtcm->extts_mask;
- u8 mask = 1 << todn;
+ /* Treat single bit ToD masks as continuous trigger */
+ return mask <= 8 && is_power_of_2(mask);
+}
+
+static int idtcm_extts_enable(struct idtcm_channel *channel,
+ struct ptp_clock_request *rq, int on)
+{
+ u8 index = rq->extts.index;
+ struct idtcm *idtcm;
+ u8 mask = 1 << index;
int err = 0;
+ u8 old_mask;
+ int ref;
+
+ idtcm = channel->idtcm;
+ old_mask = idtcm->extts_mask;

- if (todn >= MAX_TOD)
+ /* Reject requests with unsupported flags */
+ if (rq->extts.flags & ~(PTP_ENABLE_FEATURE |
+ PTP_RISING_EDGE |
+ PTP_FALLING_EDGE |
+ PTP_STRICT_FLAGS))
+ return -EOPNOTSUPP;
+
+ /* Reject requests to enable time stamping on falling edge */
+ if ((rq->extts.flags & PTP_ENABLE_FEATURE) &&
+ (rq->extts.flags & PTP_FALLING_EDGE))
+ return -EOPNOTSUPP;
+
+ if (index >= MAX_TOD)
return -EINVAL;

- if (enable) {
- if (ref > 0xF) /* E_REF_CLK15 */
- return -EINVAL;
- if (idtcm->extts_mask & mask)
- return 0;
- err = _idtcm_set_scsr_read_trig(&idtcm->channel[todn],
- SCSR_TOD_READ_TRIG_SEL_REFCLK,
- ref);
+ if (on) {
+ /* Support triggering more than one TOD_0/1/2/3 by same pin */
+ /* Use the pin configured for the channel */
+ ref = ptp_find_pin(channel->ptp_clock, PTP_PF_EXTTS, channel->tod);
+
+ if (ref < 0) {
+ dev_err(idtcm->dev, "%s: No valid pin found for TOD%d!\n",
+ __func__, channel->tod);
+ return -EBUSY;
+ }
+
+ err = arm_tod_read_trig_sel_refclk(&idtcm->channel[index], ref);
+
if (err == 0) {
idtcm->extts_mask |= mask;
- idtcm->event_channel[todn] = channel;
- idtcm->channel[todn].refn = ref;
+ idtcm->event_channel[index] = channel;
+ idtcm->channel[index].refn = ref;
+ idtcm->extts_single_shot = is_single_shot(idtcm->extts_mask);
+
+ if (old_mask)
+ return 0;
+
+ schedule_delayed_work(&idtcm->extts_work,
+ msecs_to_jiffies(EXTTS_PERIOD_MS));
}
- } else
+ } else {
idtcm->extts_mask &= ~mask;
+ idtcm->extts_single_shot = is_single_shot(idtcm->extts_mask);

- if (old_mask == 0 && idtcm->extts_mask)
- schedule_delayed_work(&idtcm->extts_work,
- msecs_to_jiffies(EXTTS_PERIOD_MS));
+ if (idtcm->extts_mask == 0)
+ cancel_delayed_work(&idtcm->extts_work);
+ }

return err;
}
@@ -371,6 +395,32 @@ static void wait_for_chip_ready(struct idtcm *idtcm)
"Continuing while SYS APLL/DPLL is not locked");
}

+static int _idtcm_gettime_triggered(struct idtcm_channel *channel,
+ struct timespec64 *ts)
+{
+ struct idtcm *idtcm = channel->idtcm;
+ u16 tod_read_cmd = IDTCM_FW_REG(idtcm->fw_ver, V520, TOD_READ_SECONDARY_CMD);
+ u8 buf[TOD_BYTE_COUNT];
+ u8 trigger;
+ int err;
+
+ err = idtcm_read(idtcm, channel->tod_read_secondary,
+ tod_read_cmd, &trigger, sizeof(trigger));
+ if (err)
+ return err;
+
+ if (trigger & TOD_READ_TRIGGER_MASK)
+ return -EBUSY;
+
+ err = idtcm_read(idtcm, channel->tod_read_secondary,
+ TOD_READ_SECONDARY_BASE, buf, sizeof(buf));
+
+ if (err)
+ return err;
+
+ return char_array_to_timespec(buf, sizeof(buf), ts);
+}
+
static int _idtcm_gettime(struct idtcm_channel *channel,
struct timespec64 *ts, u8 timeout)
{
@@ -396,13 +446,11 @@ static int _idtcm_gettime(struct idtcm_channel *channel,
} while (trigger & TOD_READ_TRIGGER_MASK);

err = idtcm_read(idtcm, channel->tod_read_primary,
- TOD_READ_PRIMARY, buf, sizeof(buf));
+ TOD_READ_PRIMARY_BASE, buf, sizeof(buf));
if (err)
return err;

- err = char_array_to_timespec(buf, sizeof(buf), ts);
-
- return err;
+ return char_array_to_timespec(buf, sizeof(buf), ts);
}

static int idtcm_extts_check_channel(struct idtcm *idtcm, u8 todn)
@@ -415,65 +463,40 @@ static int idtcm_extts_check_channel(struct idtcm *idtcm, u8 todn)

extts_channel = &idtcm->channel[todn];
ptp_channel = idtcm->event_channel[todn];
+
if (extts_channel == ptp_channel)
dco_delay = ptp_channel->dco_delay;

- err = _idtcm_gettime(extts_channel, &ts, 1);
- if (err == 0) {
- event.type = PTP_CLOCK_EXTTS;
- event.index = todn;
- event.timestamp = timespec64_to_ns(&ts) - dco_delay;
- ptp_clock_event(ptp_channel->ptp_clock, &event);
- }
- return err;
-}
+ err = _idtcm_gettime_triggered(extts_channel, &ts);

-static u8 idtcm_enable_extts_mask(struct idtcm_channel *channel,
- u8 extts_mask, bool enable)
-{
- struct idtcm *idtcm = channel->idtcm;
- int i, err;
+ if (err)
+ return err;

- for (i = 0; i < MAX_TOD; i++) {
- u8 mask = 1 << i;
- u8 refn = idtcm->channel[i].refn;
-
- if (extts_mask & mask) {
- /* check extts before disabling it */
- if (enable == false) {
- err = idtcm_extts_check_channel(idtcm, i);
- /* trigger happened so we won't re-enable it */
- if (err == 0)
- extts_mask &= ~mask;
- }
- (void)idtcm_enable_extts(channel, i, refn, enable);
- }
- }
+ /* Triggered - save timestamp */
+ event.type = PTP_CLOCK_EXTTS;
+ event.index = todn;
+ event.timestamp = timespec64_to_ns(&ts) - dco_delay;
+ ptp_clock_event(ptp_channel->ptp_clock, &event);

- return extts_mask;
+ return err;
}

static int _idtcm_gettime_immediate(struct idtcm_channel *channel,
struct timespec64 *ts)
{
struct idtcm *idtcm = channel->idtcm;
- u8 extts_mask = 0;
+
+ u16 tod_read_cmd = IDTCM_FW_REG(idtcm->fw_ver, V520, TOD_READ_PRIMARY_CMD);
+ u8 val = (SCSR_TOD_READ_TRIG_SEL_IMMEDIATE << TOD_READ_TRIGGER_SHIFT);
int err;

- /* Disable extts */
- if (idtcm->extts_mask) {
- extts_mask = idtcm_enable_extts_mask(channel, idtcm->extts_mask,
- false);
- }
+ err = idtcm_write(idtcm, channel->tod_read_primary,
+ tod_read_cmd, &val, sizeof(val));

- err = _idtcm_set_scsr_read_trig(channel,
- SCSR_TOD_READ_TRIG_SEL_IMMEDIATE, 0);
- if (err == 0)
- err = _idtcm_gettime(channel, ts, 10);
+ if (err)
+ return err;

- /* Re-enable extts */
- if (extts_mask)
- idtcm_enable_extts_mask(channel, extts_mask, true);
+ err = _idtcm_gettime(channel, ts, 10);

return err;
}
@@ -1702,6 +1725,9 @@ static int initialize_dco_operating_mode(struct idtcm_channel *channel)
/*
* Maximum absolute value for write phase offset in picoseconds
*
+ * @channel: channel
+ * @delta_ns: delta in nanoseconds
+ *
* Destination signed register is 32-bit register in resolution of 50ps
*
* 0x7fffffff * 50 = 2147483647 * 50 = 107374182350
@@ -1958,8 +1984,7 @@ static int idtcm_enable(struct ptp_clock_info *ptp,
err = idtcm_perout_enable(channel, &rq->perout, true);
break;
case PTP_CLK_REQ_EXTTS:
- err = idtcm_enable_extts(channel, rq->extts.index,
- rq->extts.rsv[0], on);
+ err = idtcm_extts_enable(channel, rq, on);
break;
default:
break;
@@ -1982,13 +2007,6 @@ static int idtcm_enable_tod(struct idtcm_channel *channel)
u8 cfg;
int err;

- /* STEELAI-366 - Temporary workaround for ts2phc compatibility */
- if (0) {
- err = idtcm_output_mask_enable(channel, false);
- if (err)
- return err;
- }
-
/*
* Start the TOD clock ticking.
*/
@@ -2038,17 +2056,35 @@ static void idtcm_set_version_info(struct idtcm *idtcm)
product_id, hw_rev_id, config_select);
}

+static int idtcm_verify_pin(struct ptp_clock_info *ptp, unsigned int pin,
+ enum ptp_pin_function func, unsigned int chan)
+{
+ switch (func) {
+ case PTP_PF_NONE:
+ case PTP_PF_EXTTS:
+ break;
+ case PTP_PF_PEROUT:
+ case PTP_PF_PHYSYNC:
+ return -1;
+ }
+ return 0;
+}
+
+static struct ptp_pin_desc pin_config[MAX_TOD][MAX_REF_CLK];
+
static const struct ptp_clock_info idtcm_caps = {
.owner = THIS_MODULE,
.max_adj = 244000,
.n_per_out = 12,
.n_ext_ts = MAX_TOD,
+ .n_pins = MAX_REF_CLK,
.adjphase = &idtcm_adjphase,
.adjfine = &idtcm_adjfine,
.adjtime = &idtcm_adjtime,
.gettime64 = &idtcm_gettime,
.settime64 = &idtcm_settime,
.enable = &idtcm_enable,
+ .verify = &idtcm_verify_pin,
.do_aux_work = &idtcm_work_handler,
};

@@ -2057,12 +2093,14 @@ static const struct ptp_clock_info idtcm_caps_deprecated = {
.max_adj = 244000,
.n_per_out = 12,
.n_ext_ts = MAX_TOD,
+ .n_pins = MAX_REF_CLK,
.adjphase = &idtcm_adjphase,
.adjfine = &idtcm_adjfine,
.adjtime = &idtcm_adjtime_deprecated,
.gettime64 = &idtcm_gettime,
.settime64 = &idtcm_settime_deprecated,
.enable = &idtcm_enable,
+ .verify = &idtcm_verify_pin,
.do_aux_work = &idtcm_work_handler,
};

@@ -2174,8 +2212,9 @@ static u32 idtcm_get_dco_delay(struct idtcm_channel *channel)
n = 1;

fodFreq = (u32)div_u64(m, n);
+
if (fodFreq >= 500000000)
- return 18 * (u32)div_u64(NSEC_PER_SEC, fodFreq);
+ return (u32)div_u64(18 * (u64)NSEC_PER_SEC, fodFreq);

return 0;
}
@@ -2188,24 +2227,28 @@ static int configure_channel_tod(struct idtcm_channel *channel, u32 index)
switch (index) {
case 0:
channel->tod_read_primary = IDTCM_FW_REG(fw_ver, V520, TOD_READ_PRIMARY_0);
+ channel->tod_read_secondary = IDTCM_FW_REG(fw_ver, V520, TOD_READ_SECONDARY_0);
channel->tod_write = IDTCM_FW_REG(fw_ver, V520, TOD_WRITE_0);
channel->tod_n = IDTCM_FW_REG(fw_ver, V520, TOD_0);
channel->sync_src = SYNC_SOURCE_DPLL0_TOD_PPS;
break;
case 1:
channel->tod_read_primary = IDTCM_FW_REG(fw_ver, V520, TOD_READ_PRIMARY_1);
+ channel->tod_read_secondary = IDTCM_FW_REG(fw_ver, V520, TOD_READ_SECONDARY_1);
channel->tod_write = IDTCM_FW_REG(fw_ver, V520, TOD_WRITE_1);
channel->tod_n = IDTCM_FW_REG(fw_ver, V520, TOD_1);
channel->sync_src = SYNC_SOURCE_DPLL1_TOD_PPS;
break;
case 2:
channel->tod_read_primary = IDTCM_FW_REG(fw_ver, V520, TOD_READ_PRIMARY_2);
+ channel->tod_read_secondary = IDTCM_FW_REG(fw_ver, V520, TOD_READ_SECONDARY_2);
channel->tod_write = IDTCM_FW_REG(fw_ver, V520, TOD_WRITE_2);
channel->tod_n = IDTCM_FW_REG(fw_ver, V520, TOD_2);
channel->sync_src = SYNC_SOURCE_DPLL2_TOD_PPS;
break;
case 3:
channel->tod_read_primary = IDTCM_FW_REG(fw_ver, V520, TOD_READ_PRIMARY_3);
+ channel->tod_read_secondary = IDTCM_FW_REG(fw_ver, V520, TOD_READ_SECONDARY_3);
channel->tod_write = IDTCM_FW_REG(fw_ver, V520, TOD_WRITE_3);
channel->tod_n = IDTCM_FW_REG(fw_ver, V520, TOD_3);
channel->sync_src = SYNC_SOURCE_DPLL3_TOD_PPS;
@@ -2221,6 +2264,7 @@ static int idtcm_enable_channel(struct idtcm *idtcm, u32 index)
{
struct idtcm_channel *channel;
int err;
+ int i;

if (!(index < MAX_TOD))
return -EINVAL;
@@ -2248,6 +2292,17 @@ static int idtcm_enable_channel(struct idtcm *idtcm, u32 index)
snprintf(channel->caps.name, sizeof(channel->caps.name),
"IDT CM TOD%u", index);

+ channel->caps.pin_config = pin_config[index];
+
+ for (i = 0; i < channel->caps.n_pins; ++i) {
+ struct ptp_pin_desc *ppd = &channel->caps.pin_config[i];
+
+ snprintf(ppd->name, sizeof(ppd->name), "input_ref%d", i);
+ ppd->index = i;
+ ppd->func = PTP_PF_NONE;
+ ppd->chan = index;
+ }
+
err = initialize_dco_operating_mode(channel);
if (err)
return err;
@@ -2302,26 +2357,40 @@ static int idtcm_enable_extts_channel(struct idtcm *idtcm, u32 index)
static void idtcm_extts_check(struct work_struct *work)
{
struct idtcm *idtcm = container_of(work, struct idtcm, extts_work.work);
- int err, i;
+ struct idtcm_channel *channel;
+ u8 mask;
+ int err;
+ int i;

if (idtcm->extts_mask == 0)
return;

mutex_lock(idtcm->lock);
+
for (i = 0; i < MAX_TOD; i++) {
- u8 mask = 1 << i;
+ mask = 1 << i;
+
+ if ((idtcm->extts_mask & mask) == 0)
+ continue;
+
+ err = idtcm_extts_check_channel(idtcm, i);

- if (idtcm->extts_mask & mask) {
- err = idtcm_extts_check_channel(idtcm, i);
+ if (err == 0) {
/* trigger clears itself, so clear the mask */
- if (err == 0)
+ if (idtcm->extts_single_shot) {
idtcm->extts_mask &= ~mask;
+ } else {
+ /* Re-arm */
+ channel = &idtcm->channel[i];
+ arm_tod_read_trig_sel_refclk(channel, channel->refn);
+ }
}
}

if (idtcm->extts_mask)
schedule_delayed_work(&idtcm->extts_work,
msecs_to_jiffies(EXTTS_PERIOD_MS));
+
mutex_unlock(idtcm->lock);
}

@@ -2342,6 +2411,11 @@ static void set_default_masks(struct idtcm *idtcm)
idtcm->tod_mask = DEFAULT_TOD_MASK;
idtcm->extts_mask = 0;

+ idtcm->channel[0].tod = 0;
+ idtcm->channel[1].tod = 1;
+ idtcm->channel[2].tod = 2;
+ idtcm->channel[3].tod = 3;
+
idtcm->channel[0].pll = DEFAULT_TOD0_PTP_PLL;
idtcm->channel[1].pll = DEFAULT_TOD1_PTP_PLL;
idtcm->channel[2].pll = DEFAULT_TOD2_PTP_PLL;
@@ -2420,8 +2494,8 @@ static int idtcm_remove(struct platform_device *pdev)
{
struct idtcm *idtcm = platform_get_drvdata(pdev);

+ idtcm->extts_mask = 0;
ptp_clock_unregister_all(idtcm);
-
cancel_delayed_work_sync(&idtcm->extts_work);

return 0;
diff --git a/drivers/ptp/ptp_clockmatrix.h b/drivers/ptp/ptp_clockmatrix.h
index 0f3059a..4379650 100644
--- a/drivers/ptp/ptp_clockmatrix.h
+++ b/drivers/ptp/ptp_clockmatrix.h
@@ -10,11 +10,13 @@

#include <linux/ktime.h>
#include <linux/mfd/idt8a340_reg.h>
+#include <linux/ptp_clock.h>
#include <linux/regmap.h>

#define FW_FILENAME "idtcm.bin"
#define MAX_TOD (4)
#define MAX_PLL (8)
+#define MAX_REF_CLK (16)

#define MAX_ABS_WRITE_PHASE_PICOSECONDS (107374182350LL)

@@ -90,6 +92,7 @@ struct idtcm_channel {
u16 dpll_ctrl_n;
u16 dpll_phase_pull_in;
u16 tod_read_primary;
+ u16 tod_read_secondary;
u16 tod_write;
u16 tod_n;
u16 hw_dpll_n;
@@ -105,6 +108,7 @@ struct idtcm_channel {
/* last input trigger for extts */
u8 refn;
u8 pll;
+ u8 tod;
u16 output_mask;
};

@@ -116,6 +120,7 @@ struct idtcm {
enum fw_version fw_ver;
/* Polls for external time stamps */
u8 extts_mask;
+ bool extts_single_shot;
struct delayed_work extts_work;
/* Remember the ptp channel to report extts */
struct idtcm_channel *event_channel[MAX_TOD];
diff --git a/include/linux/mfd/idt8a340_reg.h b/include/linux/mfd/idt8a340_reg.h
index a18c153..0c70608 100644
--- a/include/linux/mfd/idt8a340_reg.h
+++ b/include/linux/mfd/idt8a340_reg.h
@@ -407,7 +407,7 @@
#define TOD_READ_PRIMARY_0 0xcc40
#define TOD_READ_PRIMARY_0_V520 0xcc50
/* 8-bit subns, 32-bit ns, 48-bit seconds */
-#define TOD_READ_PRIMARY 0x0000
+#define TOD_READ_PRIMARY_BASE 0x0000
/* Counter increments after TOD write is completed */
#define TOD_READ_PRIMARY_COUNTER 0x000b
/* Read trigger configuration */
@@ -424,6 +424,16 @@

#define TOD_READ_SECONDARY_0 0xcc90
#define TOD_READ_SECONDARY_0_V520 0xcca0
+/* 8-bit subns, 32-bit ns, 48-bit seconds */
+#define TOD_READ_SECONDARY_BASE 0x0000
+/* Counter increments after TOD write is completed */
+#define TOD_READ_SECONDARY_COUNTER 0x000b
+/* Read trigger configuration */
+#define TOD_READ_SECONDARY_SEL_CFG_0 0x000c
+/* Read trigger selection */
+#define TOD_READ_SECONDARY_CMD 0x000e
+#define TOD_READ_SECONDARY_CMD_V520 0x000f
+
#define TOD_READ_SECONDARY_1 0xcca0
#define TOD_READ_SECONDARY_1_V520 0xccb0
#define TOD_READ_SECONDARY_2 0xccb0
--
2.7.4