net: ti: icss-iep: Add phase offset configuration for perout signal

[ Upstream commit 220cb1be647a7ca4e60241405c66f8f612c9b046 ]

icss_iep_perout_enable_hw() is a common function for generating
both pps and perout signals. When enabling pps, the application needs
to only pass enable/disable argument, whereas for perout it supports
different flags to configure the signal.

In case the app passes a valid phase offset value, the signal should
start toggling after that phase offset, else start immediately or
as soon as possible. ICSS_IEP_SYNC_START_REG register take number of
clock cycles to wait before starting the signal after activation time.
Set appropriate value to this register to support phase offset.

Signed-off-by: Meghana Malladi <m-malladi@ti.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed-by: Kory Maincent <kory.maincent@bootlin.com>
Link: https://patch.msgid.link/20250304105753.1552159-3-m-malladi@ti.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Stable-dep-of: 7349c9e99793 ("net: ti: icss-iep: Fix possible NULL pointer dereference for perout request")
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/net/ethernet/ti/icssg/icss_iep.c b/drivers/net/ethernet/ti/icssg/icss_iep.c
index 923ac58c9de5b16ef63448e3903303da1447b26a..6006276ecce6f0b98965672d87a2a7eb9ec477b0 100644 (file)
--- a/drivers/net/ethernet/ti/icssg/icss_iep.c
+++ b/drivers/net/ethernet/ti/icssg/icss_iep.c
@@ -477,6 +477,7 @@ static int icss_iep_perout_enable_hw(struct icss_iep *iep,
                                     struct ptp_perout_request *req, int on)
 {
        struct timespec64 ts;
+       u64 ns_start;
        u64 ns_width;
        int ret;
        u64 cmp;
@@ -486,6 +487,14 @@ static int icss_iep_perout_enable_hw(struct icss_iep *iep,
        ts.tv_nsec = req->on.nsec;
        ns_width = timespec64_to_ns(&ts);
 
+       if (req->flags & PTP_PEROUT_PHASE) {
+               ts.tv_sec = req->phase.sec;
+               ts.tv_nsec = req->phase.nsec;
+               ns_start = timespec64_to_ns(&ts);
+       } else {
+               ns_start = 0;
+       }
+
        if (iep->ops && iep->ops->perout_enable) {
                ret = iep->ops->perout_enable(iep->clockops_data, req, on, &cmp);
                if (ret)
@@ -500,7 +509,8 @@ static int icss_iep_perout_enable_hw(struct icss_iep *iep,
                        regmap_write(iep->map, ICSS_IEP_SYNC_PWIDTH_REG,
                                     div_u64(ns_width, iep->def_inc));
                        regmap_write(iep->map, ICSS_IEP_SYNC0_PERIOD_REG, 0);
-                       regmap_write(iep->map, ICSS_IEP_SYNC_START_REG, 0);
+                       regmap_write(iep->map, ICSS_IEP_SYNC_START_REG,
+                                    div_u64(ns_start, iep->def_inc));
                        regmap_write(iep->map, ICSS_IEP_SYNC_CTRL_REG, 0); /* one-shot mode */
                        /* Enable CMP 1 */
                        regmap_update_bits(iep->map, ICSS_IEP_CMP_CFG_REG,
@@ -527,6 +537,8 @@ static int icss_iep_perout_enable_hw(struct icss_iep *iep,
 
                        regmap_write(iep->map, ICSS_IEP_SYNC_PWIDTH_REG,
                                     div_u64(ns_width, iep->def_inc));
+                       regmap_write(iep->map, ICSS_IEP_SYNC_START_REG,
+                                    div_u64(ns_start, iep->def_inc));
                        /* Enable Sync in single shot mode  */
                        regmap_write(iep->map, ICSS_IEP_SYNC_CTRL_REG,
                                     IEP_SYNC_CTRL_SYNC_N_EN(0) | IEP_SYNC_CTRL_SYNC_EN);
@@ -557,7 +569,8 @@ static int icss_iep_perout_enable(struct icss_iep *iep,
        int ret = 0;
 
        /* Reject requests with unsupported flags */
-       if (req->flags & ~PTP_PEROUT_DUTY_CYCLE)
+       if (req->flags & ~(PTP_PEROUT_DUTY_CYCLE |
+                         PTP_PEROUT_PHASE))
                return -EOPNOTSUPP;
 
        mutex_lock(&iep->ptp_clk_mutex);
@@ -607,6 +620,7 @@ static int icss_iep_pps_enable(struct icss_iep *iep, int on)
        if (on) {
                ns = icss_iep_gettime(iep, NULL);
                ts = ns_to_timespec64(ns);
+               rq.perout.flags = 0;
                rq.perout.period.sec = 1;
                rq.perout.period.nsec = 0;
                rq.perout.start.sec = ts.tv_sec + 2;