1 files changed, 102 insertions, 0 deletions
diff --git a/arch/arm/mach-ux500/platsmp.c b/arch/arm/mach-ux500/platsmp.c
new file mode 100644
index 000000000..415d8ad2a
--- /dev/null
+++ b/arch/arm/mach-ux500/platsmp.c
@@ -0,0 +1,102 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2002 ARM Ltd.
+ * Copyright (C) 2008 STMicroelctronics.
+ * Copyright (C) 2009 ST-Ericsson.
+ * Author: Srinidhi Kasagar <srinidhi.kasagar@stericsson.com>
+ *
+ * This file is based on arm realview platform
+ */
+#include <linux/init.h>
+#include <linux/errno.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/smp.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+
+#include <asm/cacheflush.h>
+#include <asm/smp_plat.h>
+#include <asm/smp_scu.h>
+
+#include "db8500-regs.h"
+
+/* Magic triggers in backup RAM */
+#define UX500_CPU1_JUMPADDR_OFFSET 0x1FF4
+#define UX500_CPU1_WAKEMAGIC_OFFSET 0x1FF0
+
+static void __iomem *backupram;
+
+static void __init ux500_smp_prepare_cpus(unsigned int max_cpus)
+{
+	struct device_node *np;
+	static void __iomem *scu_base;
+	unsigned int ncores;
+	int i;
+
+	np = of_find_compatible_node(NULL, NULL, "ste,dbx500-backupram");
+	if (!np) {
+		pr_err("No backupram base address\n");
+		return;
+	}
+	backupram = of_iomap(np, 0);
+	of_node_put(np);
+	if (!backupram) {
+		pr_err("No backupram remap\n");
+		return;
+	}
+
+	np = of_find_compatible_node(NULL, NULL, "arm,cortex-a9-scu");
+	if (!np) {
+		pr_err("No SCU base address\n");
+		return;
+	}
+	scu_base = of_iomap(np, 0);
+	of_node_put(np);
+	if (!scu_base) {
+		pr_err("No SCU remap\n");
+		return;
+	}
+
+	scu_enable(scu_base);
+	ncores = scu_get_core_count(scu_base);
+	for (i = 0; i < ncores; i++)
+		set_cpu_possible(i, true);
+	iounmap(scu_base);
+}
+
+static int ux500_boot_secondary(unsigned int cpu, struct task_struct *idle)
+{
+	/*
+	 * write the address of secondary startup into the backup ram register
+	 * at offset 0x1FF4, then write the magic number 0xA1FEED01 to the
+	 * backup ram register at offset 0x1FF0, which is what boot rom code
+	 * is waiting for. This will wake up the secondary core from WFE.
+	 */
+	writel(__pa_symbol(secondary_startup),
+	       backupram + UX500_CPU1_JUMPADDR_OFFSET);
+	writel(0xA1FEED01,
+	       backupram + UX500_CPU1_WAKEMAGIC_OFFSET);
+
+	/* make sure write buffer is drained */
+	mb();
+	arch_send_wakeup_ipi_mask(cpumask_of(cpu));
+	return 0;
+}
+
+#ifdef CONFIG_HOTPLUG_CPU
+static void ux500_cpu_die(unsigned int cpu)
+{
+	wfi();
+}
+#endif
+
+static const struct smp_operations ux500_smp_ops __initconst = {
+	.smp_prepare_cpus	= ux500_smp_prepare_cpus,
+	.smp_boot_secondary	= ux500_boot_secondary,
+#ifdef CONFIG_HOTPLUG_CPU
+	.cpu_die		= ux500_cpu_die,
+#endif
+};
+CPU_METHOD_OF_DECLARE(ux500_smp, "ste,dbx500-smp", &ux500_smp_ops);