Resguardo inicial

linux-7.2.3/arch/arm/mach-axxia/Kconfig

@@ -0,0 +1,15 @@
+# SPDX-License-Identifier: GPL-2.0
+config ARCH_AXXIA
+	bool "LSI Axxia platforms"
+	depends on ARCH_MULTI_V7 && ARM_LPAE
+	select ARM_AMBA
+	select ARM_GIC
+	select ARM_TIMER_SP804
+	select HAVE_ARM_ARCH_TIMER
+	select MFD_SYSCON
+	select ZONE_DMA
+	help
+	  This enables support for the LSI Axxia devices.
+
+	  The LSI Axxia platforms require a Flattened Device Tree to be passed
+	  to the kernel.

linux-7.2.3/arch/arm/mach-axxia/Makefile

@@ -0,0 +1,3 @@
+# SPDX-License-Identifier: GPL-2.0
+obj-y				+= axxia.o
+obj-$(CONFIG_SMP)		+= platsmp.o

linux-7.2.3/arch/arm/mach-axxia/axxia.c

@@ -0,0 +1,19 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Support for the LSI Axxia SoC devices based on ARM cores.
+ *
+ * Copyright (C) 2012 LSI
+ */
+#include <linux/init.h>
+#include <asm/mach/arch.h>
+
+static const char *const axxia_dt_match[] __initconst = {
+	"lsi,axm5516",
+	"lsi,axm5516-sim",
+	"lsi,axm5516-emu",
+	NULL
+};
+
+DT_MACHINE_START(AXXIA_DT, "LSI Axxia AXM55XX")
+	.dt_compat = axxia_dt_match,
+MACHINE_END

linux-7.2.3/arch/arm/mach-axxia/platsmp.c

@@ -0,0 +1,87 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * linux/arch/arm/mach-axxia/platsmp.c
+ *
+ * Copyright (C) 2012 LSI Corporation
+ */
+
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/smp.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <asm/cacheflush.h>
+
+/* Syscon register offsets for releasing cores from reset */
+#define SC_CRIT_WRITE_KEY	0x1000
+#define SC_RST_CPU_HOLD		0x1010
+
+/*
+ * Write the kernel entry point for secondary CPUs to the specified address
+ */
+static void write_release_addr(u32 release_phys)
+{
+	u32 *virt = (u32 *) phys_to_virt(release_phys);
+	writel_relaxed(__pa_symbol(secondary_startup), virt);
+	/* Make sure this store is visible to other CPUs */
+	smp_wmb();
+	__cpuc_flush_dcache_area(virt, sizeof(u32));
+}
+
+static int axxia_boot_secondary(unsigned int cpu, struct task_struct *idle)
+{
+	struct device_node *syscon_np;
+	void __iomem *syscon;
+	u32 tmp;
+
+	syscon_np = of_find_compatible_node(NULL, NULL, "lsi,axxia-syscon");
+	if (!syscon_np)
+		return -ENOENT;
+
+	syscon = of_iomap(syscon_np, 0);
+	of_node_put(syscon_np);
+	if (!syscon)
+		return -ENOMEM;
+
+	tmp = readl(syscon + SC_RST_CPU_HOLD);
+	writel(0xab, syscon + SC_CRIT_WRITE_KEY);
+	tmp &= ~(1 << cpu);
+	writel(tmp, syscon + SC_RST_CPU_HOLD);
+
+	return 0;
+}
+
+static void __init axxia_smp_prepare_cpus(unsigned int max_cpus)
+{
+	int cpu_count = 0;
+	int cpu;
+
+	/*
+	 * Initialise the present map, which describes the set of CPUs actually
+	 * populated at the present time.
+	 */
+	for_each_possible_cpu(cpu) {
+		struct device_node *np;
+		u32 release_phys;
+
+		np = of_get_cpu_node(cpu, NULL);
+		if (!np)
+			continue;
+		if (of_property_read_u32(np, "cpu-release-addr", &release_phys))
+			continue;
+
+		if (cpu_count < max_cpus) {
+			set_cpu_present(cpu, true);
+			cpu_count++;
+		}
+
+		if (release_phys != 0)
+			write_release_addr(release_phys);
+	}
+}
+
+static const struct smp_operations axxia_smp_ops __initconst = {
+	.smp_prepare_cpus	= axxia_smp_prepare_cpus,
+	.smp_boot_secondary	= axxia_boot_secondary,
+};
+CPU_METHOD_OF_DECLARE(axxia_smp, "lsi,syscon-release", &axxia_smp_ops);