The IEP module supports compare events, in which a value is written to a
hardware register and when the IEP counter reaches the written value an
interrupt is generated. Add handling for this interrupt in order to
support PPS events.
Reviewed-by: Jacob Keller <jacob.e.keller@xxxxxxxxx>
Signed-off-by: Diogo Ivo <diogo.ivo@xxxxxxxxxxx>
---
drivers/net/ethernet/ti/icssg/icss_iep.c | 74 ++++++++++++++++++++++++++++++++
1 file changed, 74 insertions(+)
diff --git a/drivers/net/ethernet/ti/icssg/icss_iep.c b/drivers/net/ethernet/ti/icssg/icss_iep.c
index 3025e9c18970..b076be9c527c 100644
--- a/drivers/net/ethernet/ti/icssg/icss_iep.c
+++ b/drivers/net/ethernet/ti/icssg/icss_iep.c
@@ -17,6 +17,7 @@
#include <linux/timekeeping.h>
#include <linux/interrupt.h>
#include <linux/of_irq.h>
+#include <linux/workqueue.h>
#include "icss_iep.h"
@@ -122,6 +123,7 @@ struct icss_iep {
int cap_cmp_irq;
u64 period;
u32 latch_enable;
+ struct work_struct work;
};
/**
@@ -571,6 +573,57 @@ static int icss_iep_perout_enable(struct icss_iep *iep,
return ret;
}
+static void icss_iep_cap_cmp_work(struct work_struct *work)
+{
+ struct icss_iep *iep = container_of(work, struct icss_iep, work);
+ const u32 *reg_offs = iep->plat_data->reg_offs;
+ struct ptp_clock_event pevent;
+ unsigned int val;
+ u64 ns, ns_next;
+
+ spin_lock(&iep->irq_lock);
+
+ ns = readl(iep->base + reg_offs[ICSS_IEP_CMP1_REG0]);
+ if (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT) {
+ val = readl(iep->base + reg_offs[ICSS_IEP_CMP1_REG1]);
+ ns |= (u64)val << 32;
+ }
+ /* set next event */
+ ns_next = ns + iep->period;
+ writel(lower_32_bits(ns_next),
+ iep->base + reg_offs[ICSS_IEP_CMP1_REG0]);
+ if (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT)
+ writel(upper_32_bits(ns_next),
+ iep->base + reg_offs[ICSS_IEP_CMP1_REG1]);
+
+ pevent.pps_times.ts_real = ns_to_timespec64(ns);
+ pevent.type = PTP_CLOCK_PPSUSR;
+ pevent.index = 0;
+ ptp_clock_event(iep->ptp_clock, &pevent);
+ dev_dbg(iep->dev, "IEP:pps ts: %llu next:%llu:\n", ns, ns_next);
+
+ spin_unlock(&iep->irq_lock);
+}
+
+static irqreturn_t icss_iep_cap_cmp_irq(int irq, void *dev_id)
+{
+ struct icss_iep *iep = (struct icss_iep *)dev_id;
+ const u32 *reg_offs = iep->plat_data->reg_offs;
+ unsigned int val;
+
+ val = readl(iep->base + reg_offs[ICSS_IEP_CMP_STAT_REG]);
+ /* The driver only enables CMP1 */
+ if (val & BIT(1)) {
+ /* Clear the event */
+ writel(BIT(1), iep->base + reg_offs[ICSS_IEP_CMP_STAT_REG]);
+ if (iep->pps_enabled || iep->perout_enabled)
+ schedule_work(&iep->work);
+ return IRQ_HANDLED;
+ }
+
+ return IRQ_NONE;
+}
+
static int icss_iep_pps_enable(struct icss_iep *iep, int on)
{
struct ptp_clock_request rq;
@@ -602,6 +655,8 @@ static int icss_iep_pps_enable(struct icss_iep *iep, int on)
ret = icss_iep_perout_enable_hw(iep, &rq.perout, on);
} else {
ret = icss_iep_perout_enable_hw(iep, &rq.perout, on);
+ if (iep->cap_cmp_irq)
+ cancel_work_sync(&iep->work);
}
if (!ret)
@@ -777,6 +832,8 @@ int icss_iep_init(struct icss_iep *iep, const struct icss_iep_clockops *clkops,
if (iep->ops && iep->ops->perout_enable) {
iep->ptp_info.n_per_out = 1;
iep->ptp_info.pps = 1;
+ } else if (iep->cap_cmp_irq) {
+ iep->ptp_info.pps = 1;
}
if (iep->ops && iep->ops->extts_enable)
@@ -817,6 +874,7 @@ static int icss_iep_probe(struct platform_device *pdev)
struct device *dev = &pdev->dev;
struct icss_iep *iep;
struct clk *iep_clk;
+ int ret, irq;
iep = devm_kzalloc(dev, sizeof(*iep), GFP_KERNEL);
if (!iep)
@@ -827,6 +885,22 @@ static int icss_iep_probe(struct platform_device *pdev)
if (IS_ERR(iep->base))
return -ENODEV;
+ irq = platform_get_irq_byname_optional(pdev, "iep_cap_cmp");
+ if (irq == -EPROBE_DEFER)
+ return irq;
+
+ if (irq > 0) {
+ ret = devm_request_irq(dev, irq, icss_iep_cap_cmp_irq,
+ IRQF_TRIGGER_HIGH, "iep_cap_cmp", iep);
+ if (ret) {
+ dev_info(iep->dev, "cap_cmp irq request failed: %x\n",
+ ret);
+ } else {
+ iep->cap_cmp_irq = irq;
+ INIT_WORK(&iep->work, icss_iep_cap_cmp_work);
+ }
+ }
+
iep_clk = devm_clk_get(dev, NULL);
if (IS_ERR(iep_clk))
return PTR_ERR(iep_clk);
--
2.45.2
