Commit f18ad402 authored by Diogo Ivo's avatar Diogo Ivo Committed by David S. Miller
Browse files

net: ti: icss-iep: Enable compare events 



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: default avatarWojciech Drewek <wojciech.drewek@intel.com>
Reviewed-by: default avatarJacob Keller <jacob.e.keller@intel.com>
Signed-off-by: default avatarDiogo Ivo <diogo.ivo@siemens.com>
Reviewed-by: default avatarSimon Horman <horms@kernel.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 5056860c

drivers/net/ethernet/ti/icssg/icss_iep.c

+74 −0
Original line number Diff line number Diff line
@@ -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"
@@ -121,6 +122,7 @@ struct icss_iep { 
	int cap_cmp_irq;

	u64 period;

	u32 latch_enable;

	struct work_struct work;

};



/**
@@ -563,6 +565,57 @@ 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;



	mutex_lock(&iep->ptp_clk_mutex);



	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);



	mutex_unlock(&iep->ptp_clk_mutex);

}



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;
@@ -591,6 +644,8 @@ 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)
@@ -764,6 +819,8 @@ 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)
@@ -804,6 +861,7 @@ 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)
@@ -814,6 +872,22 @@ 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);