Linux-libre 4.8.2-gnupck-4.8.2-gnu

1 files changed, 88 insertions, 48 deletions

diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
index 4814446a0..57700541f 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -8,6 +8,9 @@
  * it under the terms of the GNU General Public License version 2 as
  * published by the Free Software Foundation.
  */
+
+#define pr_fmt(fmt)	"arm_arch_timer: " fmt
+
 #include <linux/init.h>
 #include <linux/kernel.h>
 #include <linux/device.h>
@@ -79,6 +82,14 @@ static enum ppi_nr arch_timer_uses_ppi = VIRT_PPI;
 static bool arch_timer_c3stop;
 static bool arch_timer_mem_use_virtual;
 
+static bool evtstrm_enable = IS_ENABLED(CONFIG_ARM_ARCH_TIMER_EVTSTREAM);
+
+static int __init early_evtstrm_cfg(char *buf)
+{
+	return strtobool(buf, &evtstrm_enable);
+}
+early_param("clocksource.arm_arch_timer.evtstrm", early_evtstrm_cfg);
+
 /*
  * Architected system timer support.
  */
@@ -362,17 +373,36 @@ static bool arch_timer_has_nonsecure_ppi(void)
 		arch_timer_ppi[PHYS_NONSECURE_PPI]);
 }
 
-static int arch_timer_setup(struct clock_event_device *clk)
+static u32 check_ppi_trigger(int irq)
+{
+	u32 flags = irq_get_trigger_type(irq);
+
+	if (flags != IRQF_TRIGGER_HIGH && flags != IRQF_TRIGGER_LOW) {
+		pr_warn("WARNING: Invalid trigger for IRQ%d, assuming level low\n", irq);
+		pr_warn("WARNING: Please fix your firmware\n");
+		flags = IRQF_TRIGGER_LOW;
+	}
+
+	return flags;
+}
+
+static int arch_timer_starting_cpu(unsigned int cpu)
 {
+	struct clock_event_device *clk = this_cpu_ptr(arch_timer_evt);
+	u32 flags;
+
 	__arch_timer_setup(ARCH_CP15_TIMER, clk);
 
-	enable_percpu_irq(arch_timer_ppi[arch_timer_uses_ppi], 0);
+	flags = check_ppi_trigger(arch_timer_ppi[arch_timer_uses_ppi]);
+	enable_percpu_irq(arch_timer_ppi[arch_timer_uses_ppi], flags);
 
-	if (arch_timer_has_nonsecure_ppi())
-		enable_percpu_irq(arch_timer_ppi[PHYS_NONSECURE_PPI], 0);
+	if (arch_timer_has_nonsecure_ppi()) {
+		flags = check_ppi_trigger(arch_timer_ppi[PHYS_NONSECURE_PPI]);
+		enable_percpu_irq(arch_timer_ppi[PHYS_NONSECURE_PPI], flags);
+	}
 
 	arch_counter_set_user_access();
-	if (IS_ENABLED(CONFIG_ARM_ARCH_TIMER_EVTSTREAM))
+	if (evtstrm_enable)
 		arch_timer_configure_evtstream();
 
 	return 0;
@@ -519,29 +549,14 @@ static void arch_timer_stop(struct clock_event_device *clk)
 	clk->set_state_shutdown(clk);
 }
 
-static int arch_timer_cpu_notify(struct notifier_block *self,
-					   unsigned long action, void *hcpu)
+static int arch_timer_dying_cpu(unsigned int cpu)
 {
-	/*
-	 * Grab cpu pointer in each case to avoid spurious
-	 * preemptible warnings
-	 */
-	switch (action & ~CPU_TASKS_FROZEN) {
-	case CPU_STARTING:
-		arch_timer_setup(this_cpu_ptr(arch_timer_evt));
-		break;
-	case CPU_DYING:
-		arch_timer_stop(this_cpu_ptr(arch_timer_evt));
-		break;
-	}
+	struct clock_event_device *clk = this_cpu_ptr(arch_timer_evt);
 
-	return NOTIFY_OK;
+	arch_timer_stop(clk);
+	return 0;
 }
 
-static struct notifier_block arch_timer_cpu_nb = {
-	.notifier_call = arch_timer_cpu_notify,
-};
-
 #ifdef CONFIG_CPU_PM
 static unsigned int saved_cntkctl;
 static int arch_timer_cpu_pm_notify(struct notifier_block *self,
@@ -562,11 +577,21 @@ static int __init arch_timer_cpu_pm_init(void)
 {
 	return cpu_pm_register_notifier(&arch_timer_cpu_pm_notifier);
 }
+
+static void __init arch_timer_cpu_pm_deinit(void)
+{
+	WARN_ON(cpu_pm_unregister_notifier(&arch_timer_cpu_pm_notifier));
+}
+
 #else
 static int __init arch_timer_cpu_pm_init(void)
 {
 	return 0;
 }
+
+static void __init arch_timer_cpu_pm_deinit(void)
+{
+}
 #endif
 
 static int __init arch_timer_register(void)
@@ -613,22 +638,23 @@ static int __init arch_timer_register(void)
 		goto out_free;
 	}
 
-	err = register_cpu_notifier(&arch_timer_cpu_nb);
-	if (err)
-		goto out_free_irq;
-
 	err = arch_timer_cpu_pm_init();
 	if (err)
 		goto out_unreg_notify;
 
-	/* Immediately configure the timer on the boot CPU */
-	arch_timer_setup(this_cpu_ptr(arch_timer_evt));
 
+	/* Register and immediately configure the timer on the boot CPU */
+	err = cpuhp_setup_state(CPUHP_AP_ARM_ARCH_TIMER_STARTING,
+				"AP_ARM_ARCH_TIMER_STARTING",
+				arch_timer_starting_cpu, arch_timer_dying_cpu);
+	if (err)
+		goto out_unreg_cpupm;
 	return 0;
 
+out_unreg_cpupm:
+	arch_timer_cpu_pm_deinit();
+
 out_unreg_notify:
-	unregister_cpu_notifier(&arch_timer_cpu_nb);
-out_free_irq:
 	free_percpu_irq(arch_timer_ppi[arch_timer_uses_ppi], arch_timer_evt);
 	if (arch_timer_has_nonsecure_ppi())
 		free_percpu_irq(arch_timer_ppi[PHYS_NONSECURE_PPI],
@@ -693,25 +719,26 @@ arch_timer_needs_probing(int type, const struct of_device_id *matches)
 	return needs_probing;
 }
 
-static void __init arch_timer_common_init(void)
+static int __init arch_timer_common_init(void)
 {
 	unsigned mask = ARCH_CP15_TIMER | ARCH_MEM_TIMER;
 
 	/* Wait until both nodes are probed if we have two timers */
 	if ((arch_timers_present & mask) != mask) {
 		if (arch_timer_needs_probing(ARCH_MEM_TIMER, arch_timer_mem_of_match))
-			return;
+			return 0;
 		if (arch_timer_needs_probing(ARCH_CP15_TIMER, arch_timer_of_match))
-			return;
+			return 0;
 	}
 
 	arch_timer_banner(arch_timers_present);
 	arch_counter_register(arch_timers_present);
-	arch_timer_arch_init();
+	return arch_timer_arch_init();
 }
 
-static void __init arch_timer_init(void)
+static int __init arch_timer_init(void)
 {
+	int ret;
 	/*
 	 * If HYP mode is available, we know that the physical timer
 	 * has been configured to be accessible from PL1. Use it, so
@@ -739,23 +766,30 @@ static void __init arch_timer_init(void)
 
 		if (!has_ppi) {
 			pr_warn("arch_timer: No interrupt available, giving up\n");
-			return;
+			return -EINVAL;
 		}
 	}
 
-	arch_timer_register();
-	arch_timer_common_init();
+	ret = arch_timer_register();
+	if (ret)
+		return ret;
+
+	ret = arch_timer_common_init();
+	if (ret)
+		return ret;
 
 	arch_timer_kvm_info.virtual_irq = arch_timer_ppi[VIRT_PPI];
+	
+	return 0;
 }
 
-static void __init arch_timer_of_init(struct device_node *np)
+static int __init arch_timer_of_init(struct device_node *np)
 {
 	int i;
 
 	if (arch_timers_present & ARCH_CP15_TIMER) {
 		pr_warn("arch_timer: multiple nodes in dt, skipping\n");
-		return;
+		return 0;
 	}
 
 	arch_timers_present |= ARCH_CP15_TIMER;
@@ -774,23 +808,23 @@ static void __init arch_timer_of_init(struct device_node *np)
 	    of_property_read_bool(np, "arm,cpu-registers-not-fw-configured"))
 		arch_timer_uses_ppi = PHYS_SECURE_PPI;
 
-	arch_timer_init();
+	return arch_timer_init();
 }
 CLOCKSOURCE_OF_DECLARE(armv7_arch_timer, "arm,armv7-timer", arch_timer_of_init);
 CLOCKSOURCE_OF_DECLARE(armv8_arch_timer, "arm,armv8-timer", arch_timer_of_init);
 
-static void __init arch_timer_mem_init(struct device_node *np)
+static int __init arch_timer_mem_init(struct device_node *np)
 {
 	struct device_node *frame, *best_frame = NULL;
 	void __iomem *cntctlbase, *base;
-	unsigned int irq;
+	unsigned int irq, ret = -EINVAL;
 	u32 cnttidr;
 
 	arch_timers_present |= ARCH_MEM_TIMER;
 	cntctlbase = of_iomap(np, 0);
 	if (!cntctlbase) {
 		pr_err("arch_timer: Can't find CNTCTLBase\n");
-		return;
+		return -ENXIO;
 	}
 
 	cnttidr = readl_relaxed(cntctlbase + CNTTIDR);
@@ -830,6 +864,7 @@ static void __init arch_timer_mem_init(struct device_node *np)
 		best_frame = of_node_get(frame);
 	}
 
+	ret= -ENXIO;
 	base = arch_counter_base = of_iomap(best_frame, 0);
 	if (!base) {
 		pr_err("arch_timer: Can't map frame's registers\n");
@@ -841,6 +876,7 @@ static void __init arch_timer_mem_init(struct device_node *np)
 	else
 		irq = irq_of_parse_and_map(best_frame, 0);
 
+	ret = -EINVAL;
 	if (!irq) {
 		pr_err("arch_timer: Frame missing %s irq",
 		       arch_timer_mem_use_virtual ? "virt" : "phys");
@@ -848,11 +884,15 @@ static void __init arch_timer_mem_init(struct device_node *np)
 	}
 
 	arch_timer_detect_rate(base, np);
-	arch_timer_mem_register(base, irq);
-	arch_timer_common_init();
+	ret = arch_timer_mem_register(base, irq);
+	if (ret)
+		goto out;
+
+	return arch_timer_common_init();
 out:
 	iounmap(cntctlbase);
 	of_node_put(best_frame);
+	return ret;
 }
 CLOCKSOURCE_OF_DECLARE(armv7_arch_timer_mem, "arm,armv7-timer-mem",
 		       arch_timer_mem_init);