v4.19.13 snapshot.
diff --git a/arch/arm/mach-exynos/platsmp.c b/arch/arm/mach-exynos/platsmp.c
new file mode 100644
index 0000000..6a1e682
--- /dev/null
+++ b/arch/arm/mach-exynos/platsmp.c
@@ -0,0 +1,468 @@
+// SPDX-License-Identifier: GPL-2.0
+// 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
+
+#include <linux/init.h>
+#include <linux/errno.h>
+#include <linux/delay.h>
+#include <linux/jiffies.h>
+#include <linux/smp.h>
+#include <linux/io.h>
+#include <linux/of_address.h>
+#include <linux/soc/samsung/exynos-regs-pmu.h>
+
+#include <asm/cacheflush.h>
+#include <asm/cp15.h>
+#include <asm/smp_plat.h>
+#include <asm/smp_scu.h>
+#include <asm/firmware.h>
+
+#include <mach/map.h>
+
+#include "common.h"
+
+extern void exynos4_secondary_startup(void);
+
+#ifdef CONFIG_HOTPLUG_CPU
+static inline void cpu_leave_lowpower(u32 core_id)
+{
+ unsigned int v;
+
+ asm volatile(
+ "mrc p15, 0, %0, c1, c0, 0\n"
+ " orr %0, %0, %1\n"
+ " mcr p15, 0, %0, c1, c0, 0\n"
+ " mrc p15, 0, %0, c1, c0, 1\n"
+ " orr %0, %0, %2\n"
+ " mcr p15, 0, %0, c1, c0, 1\n"
+ : "=&r" (v)
+ : "Ir" (CR_C), "Ir" (0x40)
+ : "cc");
+}
+
+static inline void platform_do_lowpower(unsigned int cpu, int *spurious)
+{
+ u32 mpidr = cpu_logical_map(cpu);
+ u32 core_id = MPIDR_AFFINITY_LEVEL(mpidr, 0);
+
+ for (;;) {
+
+ /* Turn the CPU off on next WFI instruction. */
+ exynos_cpu_power_down(core_id);
+
+ wfi();
+
+ if (pen_release == core_id) {
+ /*
+ * OK, proper wakeup, we're done
+ */
+ break;
+ }
+
+ /*
+ * Getting here, means that we have come out of WFI without
+ * having been woken up - this shouldn't happen
+ *
+ * Just note it happening - when we're woken, we can report
+ * its occurrence.
+ */
+ (*spurious)++;
+ }
+}
+#endif /* CONFIG_HOTPLUG_CPU */
+
+/**
+ * exynos_core_power_down : power down the specified cpu
+ * @cpu : the cpu to power down
+ *
+ * Power down the specified cpu. The sequence must be finished by a
+ * call to cpu_do_idle()
+ *
+ */
+void exynos_cpu_power_down(int cpu)
+{
+ u32 core_conf;
+
+ if (cpu == 0 && (soc_is_exynos5420() || soc_is_exynos5800())) {
+ /*
+ * Bypass power down for CPU0 during suspend. Check for
+ * the SYS_PWR_REG value to decide if we are suspending
+ * the system.
+ */
+ int val = pmu_raw_readl(EXYNOS5_ARM_CORE0_SYS_PWR_REG);
+
+ if (!(val & S5P_CORE_LOCAL_PWR_EN))
+ return;
+ }
+
+ core_conf = pmu_raw_readl(EXYNOS_ARM_CORE_CONFIGURATION(cpu));
+ core_conf &= ~S5P_CORE_LOCAL_PWR_EN;
+ pmu_raw_writel(core_conf, EXYNOS_ARM_CORE_CONFIGURATION(cpu));
+}
+
+/**
+ * exynos_cpu_power_up : power up the specified cpu
+ * @cpu : the cpu to power up
+ *
+ * Power up the specified cpu
+ */
+void exynos_cpu_power_up(int cpu)
+{
+ u32 core_conf = S5P_CORE_LOCAL_PWR_EN;
+
+ if (soc_is_exynos3250())
+ core_conf |= S5P_CORE_AUTOWAKEUP_EN;
+
+ pmu_raw_writel(core_conf,
+ EXYNOS_ARM_CORE_CONFIGURATION(cpu));
+}
+
+/**
+ * exynos_cpu_power_state : returns the power state of the cpu
+ * @cpu : the cpu to retrieve the power state from
+ *
+ */
+int exynos_cpu_power_state(int cpu)
+{
+ return (pmu_raw_readl(EXYNOS_ARM_CORE_STATUS(cpu)) &
+ S5P_CORE_LOCAL_PWR_EN);
+}
+
+/**
+ * exynos_cluster_power_down : power down the specified cluster
+ * @cluster : the cluster to power down
+ */
+void exynos_cluster_power_down(int cluster)
+{
+ pmu_raw_writel(0, EXYNOS_COMMON_CONFIGURATION(cluster));
+}
+
+/**
+ * exynos_cluster_power_up : power up the specified cluster
+ * @cluster : the cluster to power up
+ */
+void exynos_cluster_power_up(int cluster)
+{
+ pmu_raw_writel(S5P_CORE_LOCAL_PWR_EN,
+ EXYNOS_COMMON_CONFIGURATION(cluster));
+}
+
+/**
+ * exynos_cluster_power_state : returns the power state of the cluster
+ * @cluster : the cluster to retrieve the power state from
+ *
+ */
+int exynos_cluster_power_state(int cluster)
+{
+ return (pmu_raw_readl(EXYNOS_COMMON_STATUS(cluster)) &
+ S5P_CORE_LOCAL_PWR_EN);
+}
+
+/**
+ * exynos_scu_enable : enables SCU for Cortex-A9 based system
+ */
+void exynos_scu_enable(void)
+{
+ struct device_node *np;
+ static void __iomem *scu_base;
+
+ if (!scu_base) {
+ np = of_find_compatible_node(NULL, NULL, "arm,cortex-a9-scu");
+ if (np) {
+ scu_base = of_iomap(np, 0);
+ of_node_put(np);
+ } else {
+ scu_base = ioremap(scu_a9_get_base(), SZ_4K);
+ }
+ }
+ scu_enable(scu_base);
+}
+
+static void __iomem *cpu_boot_reg_base(void)
+{
+ if (soc_is_exynos4210() && samsung_rev() == EXYNOS4210_REV_1_1)
+ return pmu_base_addr + S5P_INFORM5;
+ return sysram_base_addr;
+}
+
+static inline void __iomem *cpu_boot_reg(int cpu)
+{
+ void __iomem *boot_reg;
+
+ boot_reg = cpu_boot_reg_base();
+ if (!boot_reg)
+ return IOMEM_ERR_PTR(-ENODEV);
+ if (soc_is_exynos4412())
+ boot_reg += 4*cpu;
+ else if (soc_is_exynos5420() || soc_is_exynos5800())
+ boot_reg += 4;
+ return boot_reg;
+}
+
+/*
+ * Set wake up by local power mode and execute software reset for given core.
+ *
+ * Currently this is needed only when booting secondary CPU on Exynos3250.
+ */
+void exynos_core_restart(u32 core_id)
+{
+ u32 val;
+
+ if (!of_machine_is_compatible("samsung,exynos3250"))
+ return;
+
+ while (!pmu_raw_readl(S5P_PMU_SPARE2))
+ udelay(10);
+ udelay(10);
+
+ val = pmu_raw_readl(EXYNOS_ARM_CORE_STATUS(core_id));
+ val |= S5P_CORE_WAKEUP_FROM_LOCAL_CFG;
+ pmu_raw_writel(val, EXYNOS_ARM_CORE_STATUS(core_id));
+
+ pmu_raw_writel(EXYNOS_CORE_PO_RESET(core_id), EXYNOS_SWRESET);
+}
+
+/*
+ * 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();
+ sync_cache_w(&pen_release);
+}
+
+static DEFINE_SPINLOCK(boot_lock);
+
+static void exynos_secondary_init(unsigned int cpu)
+{
+ /*
+ * 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);
+}
+
+int exynos_set_boot_addr(u32 core_id, unsigned long boot_addr)
+{
+ int ret;
+
+ /*
+ * Try to set boot address using firmware first
+ * and fall back to boot register if it fails.
+ */
+ ret = call_firmware_op(set_cpu_boot_addr, core_id, boot_addr);
+ if (ret && ret != -ENOSYS)
+ goto fail;
+ if (ret == -ENOSYS) {
+ void __iomem *boot_reg = cpu_boot_reg(core_id);
+
+ if (IS_ERR(boot_reg)) {
+ ret = PTR_ERR(boot_reg);
+ goto fail;
+ }
+ writel_relaxed(boot_addr, boot_reg);
+ ret = 0;
+ }
+fail:
+ return ret;
+}
+
+int exynos_get_boot_addr(u32 core_id, unsigned long *boot_addr)
+{
+ int ret;
+
+ /*
+ * Try to get boot address using firmware first
+ * and fall back to boot register if it fails.
+ */
+ ret = call_firmware_op(get_cpu_boot_addr, core_id, boot_addr);
+ if (ret && ret != -ENOSYS)
+ goto fail;
+ if (ret == -ENOSYS) {
+ void __iomem *boot_reg = cpu_boot_reg(core_id);
+
+ if (IS_ERR(boot_reg)) {
+ ret = PTR_ERR(boot_reg);
+ goto fail;
+ }
+ *boot_addr = readl_relaxed(boot_reg);
+ ret = 0;
+ }
+fail:
+ return ret;
+}
+
+static int exynos_boot_secondary(unsigned int cpu, struct task_struct *idle)
+{
+ unsigned long timeout;
+ u32 mpidr = cpu_logical_map(cpu);
+ u32 core_id = MPIDR_AFFINITY_LEVEL(mpidr, 0);
+ int ret = -ENOSYS;
+
+ /*
+ * 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 core ID, whereas
+ * "cpu" is Linux's internal ID.
+ */
+ write_pen_release(core_id);
+
+ if (!exynos_cpu_power_state(core_id)) {
+ exynos_cpu_power_up(core_id);
+ timeout = 10;
+
+ /* wait max 10 ms until cpu1 is on */
+ while (exynos_cpu_power_state(core_id)
+ != 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;
+ }
+ }
+
+ exynos_core_restart(core_id);
+
+ /*
+ * 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)) {
+ unsigned long boot_addr;
+
+ smp_rmb();
+
+ boot_addr = __pa_symbol(exynos4_secondary_startup);
+
+ ret = exynos_set_boot_addr(core_id, boot_addr);
+ if (ret)
+ goto fail;
+
+ call_firmware_op(cpu_boot, core_id);
+
+ if (soc_is_exynos3250())
+ dsb_sev();
+ else
+ arch_send_wakeup_ipi_mask(cpumask_of(cpu));
+
+ if (pen_release == -1)
+ break;
+
+ udelay(10);
+ }
+
+ if (pen_release != -1)
+ ret = -ETIMEDOUT;
+
+ /*
+ * now the secondary core is starting up let it run its
+ * calibrations, then wait for it to finish
+ */
+fail:
+ spin_unlock(&boot_lock);
+
+ return pen_release != -1 ? ret : 0;
+}
+
+static void __init exynos_smp_prepare_cpus(unsigned int max_cpus)
+{
+ int i;
+
+ exynos_sysram_init();
+
+ exynos_set_delayed_reset_assertion(true);
+
+ if (read_cpuid_part() == ARM_CPU_PART_CORTEX_A9)
+ exynos_scu_enable();
+
+ /*
+ * 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.
+ *
+ * Try using firmware operation first and fall back to
+ * boot register if it fails.
+ */
+ for (i = 1; i < max_cpus; ++i) {
+ unsigned long boot_addr;
+ u32 mpidr;
+ u32 core_id;
+ int ret;
+
+ mpidr = cpu_logical_map(i);
+ core_id = MPIDR_AFFINITY_LEVEL(mpidr, 0);
+ boot_addr = __pa_symbol(exynos4_secondary_startup);
+
+ ret = exynos_set_boot_addr(core_id, boot_addr);
+ if (ret)
+ break;
+ }
+}
+
+#ifdef CONFIG_HOTPLUG_CPU
+/*
+ * platform-specific code to shutdown a CPU
+ *
+ * Called with IRQs disabled
+ */
+static void exynos_cpu_die(unsigned int cpu)
+{
+ int spurious = 0;
+ u32 mpidr = cpu_logical_map(cpu);
+ u32 core_id = MPIDR_AFFINITY_LEVEL(mpidr, 0);
+
+ v7_exit_coherency_flush(louis);
+
+ platform_do_lowpower(cpu, &spurious);
+
+ /*
+ * bring this CPU back into the world of cache
+ * coherency, and then restore interrupts
+ */
+ cpu_leave_lowpower(core_id);
+
+ if (spurious)
+ pr_warn("CPU%u: %u spurious wakeup calls\n", cpu, spurious);
+}
+#endif /* CONFIG_HOTPLUG_CPU */
+
+const struct smp_operations exynos_smp_ops __initconst = {
+ .smp_prepare_cpus = exynos_smp_prepare_cpus,
+ .smp_secondary_init = exynos_secondary_init,
+ .smp_boot_secondary = exynos_boot_secondary,
+#ifdef CONFIG_HOTPLUG_CPU
+ .cpu_die = exynos_cpu_die,
+#endif
+};