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-rw-r--r--arch/arm/mach-uniphier/platsmp.c90
1 files changed, 90 insertions, 0 deletions
diff --git a/arch/arm/mach-uniphier/platsmp.c b/arch/arm/mach-uniphier/platsmp.c
new file mode 100644
index 000000000000..5943e1cb7fe1
--- /dev/null
+++ b/arch/arm/mach-uniphier/platsmp.c
@@ -0,0 +1,90 @@
+/*
+ * Copyright (C) 2015 Masahiro Yamada <yamada.masahiro@socionext.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/sizes.h>
+#include <linux/compiler.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/regmap.h>
+#include <linux/mfd/syscon.h>
+#include <asm/smp.h>
+#include <asm/smp_scu.h>
+
+static struct regmap *sbcm_regmap;
+
+static void __init uniphier_smp_prepare_cpus(unsigned int max_cpus)
+{
+ static cpumask_t only_cpu_0 = { CPU_BITS_CPU0 };
+ unsigned long scu_base_phys = 0;
+ void __iomem *scu_base;
+
+ sbcm_regmap = syscon_regmap_lookup_by_compatible(
+ "socionext,uniphier-system-bus-controller-misc");
+ if (IS_ERR(sbcm_regmap)) {
+ pr_err("failed to regmap system-bus-controller-misc\n");
+ goto err;
+ }
+
+ if (scu_a9_has_base())
+ scu_base_phys = scu_a9_get_base();
+
+ if (!scu_base_phys) {
+ pr_err("failed to get scu base\n");
+ goto err;
+ }
+
+ scu_base = ioremap(scu_base_phys, SZ_128);
+ if (!scu_base) {
+ pr_err("failed to remap scu base (0x%08lx)\n", scu_base_phys);
+ goto err;
+ }
+
+ scu_enable(scu_base);
+ iounmap(scu_base);
+
+ return;
+err:
+ pr_warn("disabling SMP\n");
+ init_cpu_present(&only_cpu_0);
+ sbcm_regmap = NULL;
+}
+
+static void __naked uniphier_secondary_startup(void)
+{
+ asm("bl v7_invalidate_l1\n"
+ "b secondary_startup\n");
+};
+
+static int uniphier_boot_secondary(unsigned int cpu,
+ struct task_struct *idle)
+{
+ int ret;
+
+ if (!sbcm_regmap)
+ return -ENODEV;
+
+ ret = regmap_write(sbcm_regmap, 0x1208,
+ virt_to_phys(uniphier_secondary_startup));
+ if (!ret)
+ asm("sev"); /* wake up secondary CPU */
+
+ return ret;
+}
+
+struct smp_operations uniphier_smp_ops __initdata = {
+ .smp_prepare_cpus = uniphier_smp_prepare_cpus,
+ .smp_boot_secondary = uniphier_boot_secondary,
+};
+CPU_METHOD_OF_DECLARE(uniphier_smp, "socionext,uniphier-smp",
+ &uniphier_smp_ops);