ARM: EXYNOS: Add ARCH_EXYNOS and reorganize arch/arm/mach-exynos

The arch/arm/mach-exynos4 directory (CONFIG_ARCH_EXYNOS4) has
made for plaforms based on EXYNOS4 SoCs. But since upcoming
Samsung's SoCs such as EXYNOS5 (ARM Cortex A15) can reuse most
codes in current mach-exynos4, one mach-exynos directory will
be used for them.

This patch changes to CONFIG_ARCH_EXYNOS (arch/arm/mach-exynos)
but keeps original CONFIG_ARCH_EXYNOS4 in mach-exynos/Kconfig to
avoid changing in driver side.

Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>

1 files changed, 225 insertions, 0 deletions

diff --git a/arch/arm/mach-exynos/platsmp.c b/arch/arm/mach-exynos/platsmp.c
new file mode 100644
index 000000000000..05595407e9ff
--- /dev/null
+++ b/arch/arm/mach-exynos/platsmp.c
@@ -0,0 +1,225 @@
+/* linux/arch/arm/mach-exynos4/platsmp.c
+ *
+ * Copyright (c) 2010-2011 Samsung Electronics Co., Ltd.
+ *		http://www.samsung.com
+ *
+ * Cloned from linux/arch/arm/mach-vexpress/platsmp.c
+ *
+ *  Copyright (C) 2002 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/errno.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/jiffies.h>
+#include <linux/smp.h>
+#include <linux/io.h>
+
+#include <asm/cacheflush.h>
+#include <asm/hardware/gic.h>
+#include <asm/smp_scu.h>
+#include <asm/unified.h>
+
+#include <mach/hardware.h>
+#include <mach/regs-clock.h>
+#include <mach/regs-pmu.h>
+
+#include <plat/cpu.h>
+
+extern unsigned int gic_bank_offset;
+extern void exynos4_secondary_startup(void);
+
+#define CPU1_BOOT_REG		(samsung_rev() == EXYNOS4210_REV_1_1 ? \
+				S5P_INFORM5 : S5P_VA_SYSRAM)
+
+/*
+ * control for which core is the next to come out of the secondary
+ * boot "holding pen"
+ */
+
+volatile int __cpuinitdata pen_release = -1;
+
+/*
+ * Write pen_release in a way that is guaranteed to be visible to all
+ * observers, irrespective of whether they're taking part in coherency
+ * or not.  This is necessary for the hotplug code to work reliably.
+ */
+static void write_pen_release(int val)
+{
+	pen_release = val;
+	smp_wmb();
+	__cpuc_flush_dcache_area((void *)&pen_release, sizeof(pen_release));
+	outer_clean_range(__pa(&pen_release), __pa(&pen_release + 1));
+}
+
+static void __iomem *scu_base_addr(void)
+{
+	return (void __iomem *)(S5P_VA_SCU);
+}
+
+static DEFINE_SPINLOCK(boot_lock);
+
+static void __cpuinit exynos4_gic_secondary_init(void)
+{
+	void __iomem *dist_base = S5P_VA_GIC_DIST +
+				(gic_bank_offset * smp_processor_id());
+	void __iomem *cpu_base = S5P_VA_GIC_CPU +
+				(gic_bank_offset * smp_processor_id());
+	int i;
+
+	/*
+	 * Deal with the banked PPI and SGI interrupts - disable all
+	 * PPI interrupts, ensure all SGI interrupts are enabled.
+	 */
+	__raw_writel(0xffff0000, dist_base + GIC_DIST_ENABLE_CLEAR);
+	__raw_writel(0x0000ffff, dist_base + GIC_DIST_ENABLE_SET);
+
+	/*
+	 * Set priority on PPI and SGI interrupts
+	 */
+	for (i = 0; i < 32; i += 4)
+		__raw_writel(0xa0a0a0a0, dist_base + GIC_DIST_PRI + i * 4 / 4);
+
+	__raw_writel(0xf0, cpu_base + GIC_CPU_PRIMASK);
+	__raw_writel(1, cpu_base + GIC_CPU_CTRL);
+}
+
+void __cpuinit platform_secondary_init(unsigned int cpu)
+{
+	/*
+	 * if any interrupts are already enabled for the primary
+	 * core (e.g. timer irq), then they will not have been enabled
+	 * for us: do so
+	 */
+	exynos4_gic_secondary_init();
+
+	/*
+	 * let the primary processor know we're out of the
+	 * pen, then head off into the C entry point
+	 */
+	write_pen_release(-1);
+
+	/*
+	 * Synchronise with the boot thread.
+	 */
+	spin_lock(&boot_lock);
+	spin_unlock(&boot_lock);
+
+	set_cpu_online(cpu, true);
+}
+
+int __cpuinit boot_secondary(unsigned int cpu, struct task_struct *idle)
+{
+	unsigned long timeout;
+
+	/*
+	 * Set synchronisation state between this boot processor
+	 * and the secondary one
+	 */
+	spin_lock(&boot_lock);
+
+	/*
+	 * The secondary processor is waiting to be released from
+	 * the holding pen - release it, then wait for it to flag
+	 * that it has been released by resetting pen_release.
+	 *
+	 * Note that "pen_release" is the hardware CPU ID, whereas
+	 * "cpu" is Linux's internal ID.
+	 */
+	write_pen_release(cpu_logical_map(cpu));
+
+	if (!(__raw_readl(S5P_ARM_CORE1_STATUS) & S5P_CORE_LOCAL_PWR_EN)) {
+		__raw_writel(S5P_CORE_LOCAL_PWR_EN,
+			     S5P_ARM_CORE1_CONFIGURATION);
+
+		timeout = 10;
+
+		/* wait max 10 ms until cpu1 is on */
+		while ((__raw_readl(S5P_ARM_CORE1_STATUS)
+			& S5P_CORE_LOCAL_PWR_EN) != S5P_CORE_LOCAL_PWR_EN) {
+			if (timeout-- == 0)
+				break;
+
+			mdelay(1);
+		}
+
+		if (timeout == 0) {
+			printk(KERN_ERR "cpu1 power enable failed");
+			spin_unlock(&boot_lock);
+			return -ETIMEDOUT;
+		}
+	}
+	/*
+	 * Send the secondary CPU a soft interrupt, thereby causing
+	 * the boot monitor to read the system wide flags register,
+	 * and branch to the address found there.
+	 */
+
+	timeout = jiffies + (1 * HZ);
+	while (time_before(jiffies, timeout)) {
+		smp_rmb();
+
+		__raw_writel(BSYM(virt_to_phys(exynos4_secondary_startup)),
+			CPU1_BOOT_REG);
+		gic_raise_softirq(cpumask_of(cpu), 1);
+
+		if (pen_release == -1)
+			break;
+
+		udelay(10);
+	}
+
+	/*
+	 * now the secondary core is starting up let it run its
+	 * calibrations, then wait for it to finish
+	 */
+	spin_unlock(&boot_lock);
+
+	return pen_release != -1 ? -ENOSYS : 0;
+}
+
+/*
+ * Initialise the CPU possible map early - this describes the CPUs
+ * which may be present or become present in the system.
+ */
+
+void __init smp_init_cpus(void)
+{
+	void __iomem *scu_base = scu_base_addr();
+	unsigned int i, ncores;
+
+	ncores = scu_base ? scu_get_core_count(scu_base) : 1;
+
+	/* sanity check */
+	if (ncores > nr_cpu_ids) {
+		pr_warn("SMP: %u cores greater than maximum (%u), clipping\n",
+			ncores, nr_cpu_ids);
+		ncores = nr_cpu_ids;
+	}
+
+	for (i = 0; i < ncores; i++)
+		set_cpu_possible(i, true);
+
+	set_smp_cross_call(gic_raise_softirq);
+}
+
+void __init platform_smp_prepare_cpus(unsigned int max_cpus)
+{
+
+	scu_enable(scu_base_addr());
+
+	/*
+	 * Write the address of secondary startup into the
+	 * system-wide flags register. The boot monitor waits
+	 * until it receives a soft interrupt, and then the
+	 * secondary CPU branches to this address.
+	 */
+	__raw_writel(BSYM(virt_to_phys(exynos4_secondary_startup)),
+			CPU1_BOOT_REG);
+}