Commit 47dbe4eb authored by Vincent Whitchurch's avatar Vincent Whitchurch Committed by Daniel Lezcano
Browse files

clocksource/drivers/exynos_mct: Support local-timers property 



If the device tree indicates that the hardware requires that the
processor only use certain local timers, respect that.

Signed-off-by: default avatarVincent Whitchurch <vincent.whitchurch@axis.com>
Reviewed-by: default avatarKrzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20220609112738.359385-4-vincent.whitchurch@axis.com


Signed-off-by: default avatarDaniel Lezcano <daniel.lezcano@linaro.org>
parent e8550f0e

drivers/clocksource/exynos_mct.c

+56 −6
Original line number Diff line number Diff line
@@ -33,7 +33,7 @@ 
#define EXYNOS4_MCT_G_INT_ENB		EXYNOS4_MCTREG(0x248)

#define EXYNOS4_MCT_G_WSTAT		EXYNOS4_MCTREG(0x24C)

#define _EXYNOS4_MCT_L_BASE		EXYNOS4_MCTREG(0x300)

#define EXYNOS4_MCT_L_BASE(x)		(_EXYNOS4_MCT_L_BASE + (0x100 * x))

#define EXYNOS4_MCT_L_BASE(x)		(_EXYNOS4_MCT_L_BASE + (0x100 * (x)))

#define EXYNOS4_MCT_L_MASK		(0xffffff00)



#define MCT_L_TCNTB_OFFSET		(0x00)
@@ -66,6 +66,8 @@ 
#define MCT_L0_IRQ	4

/* Max number of IRQ as per DT binding document */

#define MCT_NR_IRQS	20

/* Max number of local timers */

#define MCT_NR_LOCAL	(MCT_NR_IRQS - MCT_L0_IRQ)



enum {

	MCT_INT_SPI,
@@ -456,7 +458,6 @@ static int exynos4_mct_starting_cpu(unsigned int cpu) 
		per_cpu_ptr(&percpu_mct_tick, cpu);

	struct clock_event_device *evt = &mevt->evt;



	mevt->base = EXYNOS4_MCT_L_BASE(cpu);

	snprintf(mevt->name, sizeof(mevt->name), "mct_tick%d", cpu);



	evt->name = mevt->name;
@@ -527,8 +528,17 @@ static int __init exynos4_timer_resources(struct device_node *np) 
	return 0;

}



/**

 * exynos4_timer_interrupts - initialize MCT interrupts

 * @np: device node for MCT

 * @int_type: interrupt type, MCT_INT_PPI or MCT_INT_SPI

 * @local_idx: array mapping CPU numbers to local timer indices

 * @nr_local: size of @local_idx array

 */

static int __init exynos4_timer_interrupts(struct device_node *np,

					   unsigned int int_type)

					   unsigned int int_type,

					   const u32 *local_idx,

					   size_t nr_local)

{

	int nr_irqs, i, err, cpu;
@@ -561,13 +571,21 @@ static int __init exynos4_timer_interrupts(struct device_node *np, 
	} else {

		for_each_possible_cpu(cpu) {

			int mct_irq;

			unsigned int irq_idx;

			struct mct_clock_event_device *pcpu_mevt =

				per_cpu_ptr(&percpu_mct_tick, cpu);



			if (cpu >= nr_local) {

				err = -EINVAL;

				goto out_irq;

			}



			irq_idx = MCT_L0_IRQ + local_idx[cpu];



			pcpu_mevt->evt.irq = -1;

			if (MCT_L0_IRQ + cpu >= ARRAY_SIZE(mct_irqs))

			if (irq_idx >= ARRAY_SIZE(mct_irqs))

				break;

			mct_irq = mct_irqs[MCT_L0_IRQ + cpu];

			mct_irq = mct_irqs[irq_idx];



			irq_set_status_flags(mct_irq, IRQ_NOAUTOEN);

			if (request_irq(mct_irq,
@@ -583,6 +601,17 @@ static int __init exynos4_timer_interrupts(struct device_node *np, 
		}

	}



	for_each_possible_cpu(cpu) {

		struct mct_clock_event_device *mevt = per_cpu_ptr(&percpu_mct_tick, cpu);



		if (cpu >= nr_local) {

			err = -EINVAL;

			goto out_irq;

		}



		mevt->base = EXYNOS4_MCT_L_BASE(local_idx[cpu]);

	}



	/* Install hotplug callbacks which configure the timer on this CPU */

	err = cpuhp_setup_state(CPUHP_AP_EXYNOS4_MCT_TIMER_STARTING,

				"clockevents/exynos4/mct_timer:starting",
@@ -613,13 +642,34 @@ static int __init exynos4_timer_interrupts(struct device_node *np, 
static int __init mct_init_dt(struct device_node *np, unsigned int int_type)

{

	bool frc_shared = of_property_read_bool(np, "samsung,frc-shared");

	u32 local_idx[MCT_NR_LOCAL] = {0};

	int nr_local;

	int ret;



	nr_local = of_property_count_u32_elems(np, "samsung,local-timers");

	if (nr_local == 0)

		return -EINVAL;

	if (nr_local > 0) {

		if (nr_local > ARRAY_SIZE(local_idx))

			return -EINVAL;



		ret = of_property_read_u32_array(np, "samsung,local-timers",

						 local_idx, nr_local);

		if (ret)

			return ret;

	} else {

		int i;



		nr_local = ARRAY_SIZE(local_idx);

		for (i = 0; i < nr_local; i++)

			local_idx[i] = i;

	}



	ret = exynos4_timer_resources(np);

	if (ret)

		return ret;



	ret = exynos4_timer_interrupts(np, int_type);

	ret = exynos4_timer_interrupts(np, int_type, local_idx, nr_local);

	if (ret)

		return ret;