Merge branch 'for-linus' of git://git.linaro.org/people/rmk/linux-arm

Pull core ARM updates from Russell King:
 "This is the bulk of the core ARM updates for this merge window.
  Included in here is a different way to handle the VIVT cache flushing
  on context switch, which should allow scheduler folk to remove a
  special case in their core code.

  We have architectured timer support here, which is a set of timers
  specified by the ARM architecture for future SoCs.  So we should see
  less variability in timer design going forward.

  The last big thing here is my cleanup to the way we handle PCI across
  ARM, fixing some oddities in some platforms which hadn't realised
  there was a way to deal with their private data already built in to
  our PCI backend.

  I've also removed support for the ARMv3 architecture; it hasn't worked
  properly for years so it seems pointless to keep it around."

* 'for-linus' of git://git.linaro.org/people/rmk/linux-arm: (47 commits)
  ARM: PCI: remove per-pci_hw list of buses
  ARM: PCI: dove/kirkwood/mv78xx0: use sys->private_data
  ARM: PCI: provide a default bus scan implementation
  ARM: PCI: get rid of pci_std_swizzle()
  ARM: PCI: versatile: fix PCI interrupt setup
  ARM: PCI: integrator: use common PCI swizzle
  ARM: 7416/1: LPAE: Remove unused L_PTE_(BUFFERABLE|CACHEABLE) macros
  ARM: 7415/1: vfp: convert printk's to pr_*'s
  ARM: decompressor: avoid speculative prefetch from non-RAM areas
  ARM: Remove ARMv3 support from decompressor
  ARM: 7413/1: move read_{boot,persistent}_clock to the architecture level
  ARM: Remove support for ARMv3 ARM610 and ARM710 CPUs
  ARM: 7363/1: DEBUG_LL: limit early mapping to the minimum
  ARM: 7391/1: versatile: add some auxdata for device trees
  ARM: 7389/2: plat-versatile: modernize FPGA IRQ controller
  AMBA: get rid of last two uses of NO_IRQ
  ARM: 7408/1: cacheflush: return error to userspace when flushing syscall fails
  ARM: 7409/1: Do not call flush_cache_user_range with mmap_sem held
  ARM: 7404/1: cmpxchg64: use atomic64 and local64 routines for cmpxchg64
  ARM: 7347/1: SCU: use cpu_logical_map for per-CPU low power mode
  ...

1 files changed, 350 insertions, 0 deletions

diff --git a/arch/arm/kernel/arch_timer.c b/arch/arm/kernel/arch_timer.c
new file mode 100644
index 000000000000..dd58035621f7
--- /dev/null
+++ b/arch/arm/kernel/arch_timer.c
@@ -0,0 +1,350 @@
+/*
+ *  linux/arch/arm/kernel/arch_timer.c
+ *
+ *  Copyright (C) 2011 ARM Ltd.
+ *  All Rights Reserved
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/smp.h>
+#include <linux/cpu.h>
+#include <linux/jiffies.h>
+#include <linux/clockchips.h>
+#include <linux/interrupt.h>
+#include <linux/of_irq.h>
+#include <linux/io.h>
+
+#include <asm/cputype.h>
+#include <asm/localtimer.h>
+#include <asm/arch_timer.h>
+#include <asm/system_info.h>
+#include <asm/sched_clock.h>
+
+static unsigned long arch_timer_rate;
+static int arch_timer_ppi;
+static int arch_timer_ppi2;
+
+static struct clock_event_device __percpu **arch_timer_evt;
+
+/*
+ * Architected system timer support.
+ */
+
+#define ARCH_TIMER_CTRL_ENABLE		(1 << 0)
+#define ARCH_TIMER_CTRL_IT_MASK		(1 << 1)
+#define ARCH_TIMER_CTRL_IT_STAT		(1 << 2)
+
+#define ARCH_TIMER_REG_CTRL		0
+#define ARCH_TIMER_REG_FREQ		1
+#define ARCH_TIMER_REG_TVAL		2
+
+static void arch_timer_reg_write(int reg, u32 val)
+{
+	switch (reg) {
+	case ARCH_TIMER_REG_CTRL:
+		asm volatile("mcr p15, 0, %0, c14, c2, 1" : : "r" (val));
+		break;
+	case ARCH_TIMER_REG_TVAL:
+		asm volatile("mcr p15, 0, %0, c14, c2, 0" : : "r" (val));
+		break;
+	}
+
+	isb();
+}
+
+static u32 arch_timer_reg_read(int reg)
+{
+	u32 val;
+
+	switch (reg) {
+	case ARCH_TIMER_REG_CTRL:
+		asm volatile("mrc p15, 0, %0, c14, c2, 1" : "=r" (val));
+		break;
+	case ARCH_TIMER_REG_FREQ:
+		asm volatile("mrc p15, 0, %0, c14, c0, 0" : "=r" (val));
+		break;
+	case ARCH_TIMER_REG_TVAL:
+		asm volatile("mrc p15, 0, %0, c14, c2, 0" : "=r" (val));
+		break;
+	default:
+		BUG();
+	}
+
+	return val;
+}
+
+static irqreturn_t arch_timer_handler(int irq, void *dev_id)
+{
+	struct clock_event_device *evt = *(struct clock_event_device **)dev_id;
+	unsigned long ctrl;
+
+	ctrl = arch_timer_reg_read(ARCH_TIMER_REG_CTRL);
+	if (ctrl & ARCH_TIMER_CTRL_IT_STAT) {
+		ctrl |= ARCH_TIMER_CTRL_IT_MASK;
+		arch_timer_reg_write(ARCH_TIMER_REG_CTRL, ctrl);
+		evt->event_handler(evt);
+		return IRQ_HANDLED;
+	}
+
+	return IRQ_NONE;
+}
+
+static void arch_timer_disable(void)
+{
+	unsigned long ctrl;
+
+	ctrl = arch_timer_reg_read(ARCH_TIMER_REG_CTRL);
+	ctrl &= ~ARCH_TIMER_CTRL_ENABLE;
+	arch_timer_reg_write(ARCH_TIMER_REG_CTRL, ctrl);
+}
+
+static void arch_timer_set_mode(enum clock_event_mode mode,
+				struct clock_event_device *clk)
+{
+	switch (mode) {
+	case CLOCK_EVT_MODE_UNUSED:
+	case CLOCK_EVT_MODE_SHUTDOWN:
+		arch_timer_disable();
+		break;
+	default:
+		break;
+	}
+}
+
+static int arch_timer_set_next_event(unsigned long evt,
+				     struct clock_event_device *unused)
+{
+	unsigned long ctrl;
+
+	ctrl = arch_timer_reg_read(ARCH_TIMER_REG_CTRL);
+	ctrl |= ARCH_TIMER_CTRL_ENABLE;
+	ctrl &= ~ARCH_TIMER_CTRL_IT_MASK;
+
+	arch_timer_reg_write(ARCH_TIMER_REG_TVAL, evt);
+	arch_timer_reg_write(ARCH_TIMER_REG_CTRL, ctrl);
+
+	return 0;
+}
+
+static int __cpuinit arch_timer_setup(struct clock_event_device *clk)
+{
+	/* Be safe... */
+	arch_timer_disable();
+
+	clk->features = CLOCK_EVT_FEAT_ONESHOT;
+	clk->name = "arch_sys_timer";
+	clk->rating = 450;
+	clk->set_mode = arch_timer_set_mode;
+	clk->set_next_event = arch_timer_set_next_event;
+	clk->irq = arch_timer_ppi;
+
+	clockevents_config_and_register(clk, arch_timer_rate,
+					0xf, 0x7fffffff);
+
+	*__this_cpu_ptr(arch_timer_evt) = clk;
+
+	enable_percpu_irq(clk->irq, 0);
+	if (arch_timer_ppi2)
+		enable_percpu_irq(arch_timer_ppi2, 0);
+
+	return 0;
+}
+
+/* Is the optional system timer available? */
+static int local_timer_is_architected(void)
+{
+	return (cpu_architecture() >= CPU_ARCH_ARMv7) &&
+	       ((read_cpuid_ext(CPUID_EXT_PFR1) >> 16) & 0xf) == 1;
+}
+
+static int arch_timer_available(void)
+{
+	unsigned long freq;
+
+	if (!local_timer_is_architected())
+		return -ENXIO;
+
+	if (arch_timer_rate == 0) {
+		arch_timer_reg_write(ARCH_TIMER_REG_CTRL, 0);
+		freq = arch_timer_reg_read(ARCH_TIMER_REG_FREQ);
+
+		/* Check the timer frequency. */
+		if (freq == 0) {
+			pr_warn("Architected timer frequency not available\n");
+			return -EINVAL;
+		}
+
+		arch_timer_rate = freq;
+	}
+
+	pr_info_once("Architected local timer running at %lu.%02luMHz.\n",
+		     arch_timer_rate / 1000000, (arch_timer_rate / 10000) % 100);
+	return 0;
+}
+
+static inline cycle_t arch_counter_get_cntpct(void)
+{
+	u32 cvall, cvalh;
+
+	asm volatile("mrrc p15, 0, %0, %1, c14" : "=r" (cvall), "=r" (cvalh));
+
+	return ((cycle_t) cvalh << 32) | cvall;
+}
+
+static inline cycle_t arch_counter_get_cntvct(void)
+{
+	u32 cvall, cvalh;
+
+	asm volatile("mrrc p15, 1, %0, %1, c14" : "=r" (cvall), "=r" (cvalh));
+
+	return ((cycle_t) cvalh << 32) | cvall;
+}
+
+static u32 notrace arch_counter_get_cntvct32(void)
+{
+	cycle_t cntvct = arch_counter_get_cntvct();
+
+	/*
+	 * The sched_clock infrastructure only knows about counters
+	 * with at most 32bits. Forget about the upper 24 bits for the
+	 * time being...
+	 */
+	return (u32)(cntvct & (u32)~0);
+}
+
+static cycle_t arch_counter_read(struct clocksource *cs)
+{
+	return arch_counter_get_cntpct();
+}
+
+static struct clocksource clocksource_counter = {
+	.name	= "arch_sys_counter",
+	.rating	= 400,
+	.read	= arch_counter_read,
+	.mask	= CLOCKSOURCE_MASK(56),
+	.flags	= CLOCK_SOURCE_IS_CONTINUOUS,
+};
+
+static void __cpuinit arch_timer_stop(struct clock_event_device *clk)
+{
+	pr_debug("arch_timer_teardown disable IRQ%d cpu #%d\n",
+		 clk->irq, smp_processor_id());
+	disable_percpu_irq(clk->irq);
+	if (arch_timer_ppi2)
+		disable_percpu_irq(arch_timer_ppi2);
+	arch_timer_set_mode(CLOCK_EVT_MODE_UNUSED, clk);
+}
+
+static struct local_timer_ops arch_timer_ops __cpuinitdata = {
+	.setup	= arch_timer_setup,
+	.stop	= arch_timer_stop,
+};
+
+static struct clock_event_device arch_timer_global_evt;
+
+static int __init arch_timer_register(void)
+{
+	int err;
+
+	err = arch_timer_available();
+	if (err)
+		return err;
+
+	arch_timer_evt = alloc_percpu(struct clock_event_device *);
+	if (!arch_timer_evt)
+		return -ENOMEM;
+
+	clocksource_register_hz(&clocksource_counter, arch_timer_rate);
+
+	err = request_percpu_irq(arch_timer_ppi, arch_timer_handler,
+				 "arch_timer", arch_timer_evt);
+	if (err) {
+		pr_err("arch_timer: can't register interrupt %d (%d)\n",
+		       arch_timer_ppi, err);
+		goto out_free;
+	}
+
+	if (arch_timer_ppi2) {
+		err = request_percpu_irq(arch_timer_ppi2, arch_timer_handler,
+					 "arch_timer", arch_timer_evt);
+		if (err) {
+			pr_err("arch_timer: can't register interrupt %d (%d)\n",
+			       arch_timer_ppi2, err);
+			arch_timer_ppi2 = 0;
+			goto out_free_irq;
+		}
+	}
+
+	err = local_timer_register(&arch_timer_ops);
+	if (err) {
+		/*
+		 * We couldn't register as a local timer (could be
+		 * because we're on a UP platform, or because some
+		 * other local timer is already present...). Try as a
+		 * global timer instead.
+		 */
+		arch_timer_global_evt.cpumask = cpumask_of(0);
+		err = arch_timer_setup(&arch_timer_global_evt);
+	}
+
+	if (err)
+		goto out_free_irq;
+
+	return 0;
+
+out_free_irq:
+	free_percpu_irq(arch_timer_ppi, arch_timer_evt);
+	if (arch_timer_ppi2)
+		free_percpu_irq(arch_timer_ppi2, arch_timer_evt);
+
+out_free:
+	free_percpu(arch_timer_evt);
+
+	return err;
+}
+
+static const struct of_device_id arch_timer_of_match[] __initconst = {
+	{ .compatible	= "arm,armv7-timer",	},
+	{},
+};
+
+int __init arch_timer_of_register(void)
+{
+	struct device_node *np;
+	u32 freq;
+
+	np = of_find_matching_node(NULL, arch_timer_of_match);
+	if (!np) {
+		pr_err("arch_timer: can't find DT node\n");
+		return -ENODEV;
+	}
+
+	/* Try to determine the frequency from the device tree or CNTFRQ */
+	if (!of_property_read_u32(np, "clock-frequency", &freq))
+		arch_timer_rate = freq;
+
+	arch_timer_ppi = irq_of_parse_and_map(np, 0);
+	arch_timer_ppi2 = irq_of_parse_and_map(np, 1);
+	pr_info("arch_timer: found %s irqs %d %d\n",
+		np->name, arch_timer_ppi, arch_timer_ppi2);
+
+	return arch_timer_register();
+}
+
+int __init arch_timer_sched_clock_init(void)
+{
+	int err;
+
+	err = arch_timer_available();
+	if (err)
+		return err;
+
+	setup_sched_clock(arch_counter_get_cntvct32, 32, arch_timer_rate);
+	return 0;
+}