Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 100 insertions, 0 deletions

diff --git a/arch/arm/mach-sti/platsmp.c b/arch/arm/mach-sti/platsmp.c
new file mode 100644
index 0000000000..e2ba04b562
--- /dev/null
+++ b/arch/arm/mach-sti/platsmp.c
@@ -0,0 +1,100 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ *  arch/arm/mach-sti/platsmp.c
+ *
+ * Copyright (C) 2013 STMicroelectronics (R&D) Limited.
+ *		http://www.st.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/smp.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/memblock.h>
+
+#include <asm/cacheflush.h>
+#include <asm/smp_plat.h>
+#include <asm/smp_scu.h>
+
+#include "smp.h"
+
+static u32 __iomem *cpu_strt_ptr;
+
+static int sti_boot_secondary(unsigned int cpu, struct task_struct *idle)
+{
+	unsigned long entry_pa = __pa_symbol(secondary_startup);
+
+	/*
+	 * Secondary CPU is initialised and started by a U-BOOTROM firmware.
+	 * Secondary CPU is spinning and waiting for a write at cpu_strt_ptr.
+	 * Writing secondary_startup address at cpu_strt_ptr makes it to
+	 * jump directly to secondary_startup().
+	 */
+	__raw_writel(entry_pa, cpu_strt_ptr);
+
+	/* wmb so that data is actually written before cache flush is done */
+	smp_wmb();
+	sync_cache_w(cpu_strt_ptr);
+
+	return 0;
+}
+
+static void __init sti_smp_prepare_cpus(unsigned int max_cpus)
+{
+	struct device_node *np;
+	void __iomem *scu_base;
+	u32 release_phys;
+	int cpu;
+
+	np = of_find_compatible_node(NULL, NULL, "arm,cortex-a9-scu");
+
+	if (np) {
+		scu_base = of_iomap(np, 0);
+		scu_enable(scu_base);
+		of_node_put(np);
+	}
+
+	if (max_cpus <= 1)
+		return;
+
+	for_each_possible_cpu(cpu) {
+
+		np = of_get_cpu_node(cpu, NULL);
+
+		if (!np)
+			continue;
+
+		if (of_property_read_u32(np, "cpu-release-addr",
+						&release_phys)) {
+			pr_err("CPU %d: missing or invalid cpu-release-addr "
+				"property\n", cpu);
+			continue;
+		}
+
+		/*
+		 * cpu-release-addr is usually configured in SBC DMEM but can
+		 * also be in RAM.
+		 */
+
+		if (!memblock_is_memory(release_phys))
+			cpu_strt_ptr =
+				ioremap(release_phys, sizeof(release_phys));
+		else
+			cpu_strt_ptr =
+				(u32 __iomem *)phys_to_virt(release_phys);
+
+		set_cpu_possible(cpu, true);
+	}
+}
+
+const struct smp_operations sti_smp_ops __initconst = {
+	.smp_prepare_cpus	= sti_smp_prepare_cpus,
+	.smp_boot_secondary	= sti_boot_secondary,
+};