1 files changed, 175 insertions, 59 deletions

diff --git a/arch/arm/kernel/devtree.c b/arch/arm/kernel/devtree.c
index bee7f9d47f0..11c54de9f8c 100644
--- a/arch/arm/kernel/devtree.c
+++ b/arch/arm/kernel/devtree.c
@@ -18,47 +18,180 @@
 #include <linux/of_fdt.h>
 #include <linux/of_irq.h>
 #include <linux/of_platform.h>
+#include <linux/smp.h>
 
+#include <asm/cputype.h>
 #include <asm/setup.h>
 #include <asm/page.h>
+#include <asm/smp_plat.h>
 #include <asm/mach/arch.h>
 #include <asm/mach-types.h>
 
-void __init early_init_dt_add_memory_arch(u64 base, u64 size)
+
+#ifdef CONFIG_SMP
+extern struct of_cpu_method __cpu_method_of_table[];
+
+static const struct of_cpu_method __cpu_method_of_table_sentinel
+	__used __section(__cpu_method_of_table_end);
+
+
+static int __init set_smp_ops_by_method(struct device_node *node)
 {
-	arm_add_memory(base, size);
-}
+	const char *method;
+	struct of_cpu_method *m = __cpu_method_of_table;
+
+	if (of_property_read_string(node, "enable-method", &method))
+		return 0;
 
-void * __init early_init_dt_alloc_memory_arch(u64 size, u64 align)
+	for (; m->method; m++)
+		if (!strcmp(m->method, method)) {
+			smp_set_ops(m->ops);
+			return 1;
+		}
+
+	return 0;
+}
+#else
+static inline int set_smp_ops_by_method(struct device_node *node)
 {
-	return alloc_bootmem_align(size, align);
+	return 1;
 }
+#endif
 
-void __init arm_dt_memblock_reserve(void)
+
+/*
+ * arm_dt_init_cpu_maps - Function retrieves cpu nodes from the device tree
+ * and builds the cpu logical map array containing MPIDR values related to
+ * logical cpus
+ *
+ * Updates the cpu possible mask with the number of parsed cpu nodes
+ */
+void __init arm_dt_init_cpu_maps(void)
 {
-	u64 *reserve_map, base, size;
+	/*
+	 * Temp logical map is initialized with UINT_MAX values that are
+	 * considered invalid logical map entries since the logical map must
+	 * contain a list of MPIDR[23:0] values where MPIDR[31:24] must
+	 * read as 0.
+	 */
+	struct device_node *cpu, *cpus;
+	int found_method = 0;
+	u32 i, j, cpuidx = 1;
+	u32 mpidr = is_smp() ? read_cpuid_mpidr() & MPIDR_HWID_BITMASK : 0;
 
-	if (!initial_boot_params)
+	u32 tmp_map[NR_CPUS] = { [0 ... NR_CPUS-1] = MPIDR_INVALID };
+	bool bootcpu_valid = false;
+	cpus = of_find_node_by_path("/cpus");
+
+	if (!cpus)
 		return;
 
-	/* Reserve the dtb region */
-	memblock_reserve(virt_to_phys(initial_boot_params),
-			 be32_to_cpu(initial_boot_params->totalsize));
+	for_each_child_of_node(cpus, cpu) {
+		u32 hwid;
+
+		if (of_node_cmp(cpu->type, "cpu"))
+			continue;
+
+		pr_debug(" * %s...\n", cpu->full_name);
+		/*
+		 * A device tree containing CPU nodes with missing "reg"
+		 * properties is considered invalid to build the
+		 * cpu_logical_map.
+		 */
+		if (of_property_read_u32(cpu, "reg", &hwid)) {
+			pr_debug(" * %s missing reg property\n",
+				     cpu->full_name);
+			return;
+		}
+
+		/*
+		 * 8 MSBs must be set to 0 in the DT since the reg property
+		 * defines the MPIDR[23:0].
+		 */
+		if (hwid & ~MPIDR_HWID_BITMASK)
+			return;
+
+		/*
+		 * Duplicate MPIDRs are a recipe for disaster.
+		 * Scan all initialized entries and check for
+		 * duplicates. If any is found just bail out.
+		 * temp values were initialized to UINT_MAX
+		 * to avoid matching valid MPIDR[23:0] values.
+		 */
+		for (j = 0; j < cpuidx; j++)
+			if (WARN(tmp_map[j] == hwid, "Duplicate /cpu reg "
+						     "properties in the DT\n"))
+				return;
+
+		/*
+		 * Build a stashed array of MPIDR values. Numbering scheme
+		 * requires that if detected the boot CPU must be assigned
+		 * logical id 0. Other CPUs get sequential indexes starting
+		 * from 1. If a CPU node with a reg property matching the
+		 * boot CPU MPIDR is detected, this is recorded so that the
+		 * logical map built from DT is validated and can be used
+		 * to override the map created in smp_setup_processor_id().
+		 */
+		if (hwid == mpidr) {
+			i = 0;
+			bootcpu_valid = true;
+		} else {
+			i = cpuidx++;
+		}
+
+		if (WARN(cpuidx > nr_cpu_ids, "DT /cpu %u nodes greater than "
+					       "max cores %u, capping them\n",
+					       cpuidx, nr_cpu_ids)) {
+			cpuidx = nr_cpu_ids;
+			break;
+		}
+
+		tmp_map[i] = hwid;
+
+		if (!found_method)
+			found_method = set_smp_ops_by_method(cpu);
+	}
 
 	/*
-	 * Process the reserve map.  This will probably overlap the initrd
-	 * and dtb locations which are already reserved, but overlaping
-	 * doesn't hurt anything
+	 * Fallback to an enable-method in the cpus node if nothing found in
+	 * a cpu node.
 	 */
-	reserve_map = ((void*)initial_boot_params) +
-			be32_to_cpu(initial_boot_params->off_mem_rsvmap);
-	while (1) {
-		base = be64_to_cpup(reserve_map++);
-		size = be64_to_cpup(reserve_map++);
-		if (!size)
-			break;
-		memblock_reserve(base, size);
+	if (!found_method)
+		set_smp_ops_by_method(cpus);
+
+	if (!bootcpu_valid) {
+		pr_warn("DT missing boot CPU MPIDR[23:0], fall back to default cpu_logical_map\n");
+		return;
 	}
+
+	/*
+	 * Since the boot CPU node contains proper data, and all nodes have
+	 * a reg property, the DT CPU list can be considered valid and the
+	 * logical map created in smp_setup_processor_id() can be overridden
+	 */
+	for (i = 0; i < cpuidx; i++) {
+		set_cpu_possible(i, true);
+		cpu_logical_map(i) = tmp_map[i];
+		pr_debug("cpu logical map 0x%x\n", cpu_logical_map(i));
+	}
+}
+
+bool arch_match_cpu_phys_id(int cpu, u64 phys_id)
+{
+	return phys_id == cpu_logical_map(cpu);
+}
+
+static const void * __init arch_get_next_mach(const char *const **match)
+{
+	static const struct machine_desc *mdesc = __arch_info_begin;
+	const struct machine_desc *m = mdesc;
+
+	if (m >= __arch_info_end)
+		return NULL;
+
+	mdesc++;
+	*match = m->dt_compat;
+	return m;
 }
 
 /**
@@ -68,40 +201,31 @@ void __init arm_dt_memblock_reserve(void)
  * If a dtb was passed to the kernel in r2, then use it to choose the
  * correct machine_desc and to setup the system.
  */
-struct machine_desc * __init setup_machine_fdt(unsigned int dt_phys)
+const struct machine_desc * __init setup_machine_fdt(unsigned int dt_phys)
 {
-	struct boot_param_header *devtree;
-	struct machine_desc *mdesc, *mdesc_best = NULL;
-	unsigned int score, mdesc_score = ~1;
-	unsigned long dt_root;
-	const char *model;
+	const struct machine_desc *mdesc, *mdesc_best = NULL;
 
-	if (!dt_phys)
-		return NULL;
+#ifdef CONFIG_ARCH_MULTIPLATFORM
+	DT_MACHINE_START(GENERIC_DT, "Generic DT based system")
+	MACHINE_END
 
-	devtree = phys_to_virt(dt_phys);
+	mdesc_best = &__mach_desc_GENERIC_DT;
+#endif
 
-	/* check device tree validity */
-	if (be32_to_cpu(devtree->magic) != OF_DT_HEADER)
+	if (!dt_phys || !early_init_dt_verify(phys_to_virt(dt_phys)))
 		return NULL;
 
-	/* Search the mdescs for the 'best' compatible value match */
-	initial_boot_params = devtree;
-	dt_root = of_get_flat_dt_root();
-	for_each_machine_desc(mdesc) {
-		score = of_flat_dt_match(dt_root, mdesc->dt_compat);
-		if (score > 0 && score < mdesc_score) {
-			mdesc_best = mdesc;
-			mdesc_score = score;
-		}
-	}
-	if (!mdesc_best) {
+	mdesc = of_flat_dt_match_machine(mdesc_best, arch_get_next_mach);
+
+	if (!mdesc) {
 		const char *prop;
-		long size;
+		int size;
+		unsigned long dt_root;
 
 		early_print("\nError: unrecognized/unsupported "
 			    "device tree compatible list:\n[ ");
 
+		dt_root = of_get_flat_dt_root();
 		prop = of_get_flat_dt_prop(dt_root, "compatible", &size);
 		while (size > 0) {
 			early_print("'%s' ", prop);
@@ -113,22 +237,14 @@ struct machine_desc * __init setup_machine_fdt(unsigned int dt_phys)
 		dump_machine_table(); /* does not return */
 	}
 
-	model = of_get_flat_dt_prop(dt_root, "model", NULL);
-	if (!model)
-		model = of_get_flat_dt_prop(dt_root, "compatible", NULL);
-	if (!model)
-		model = "<unknown>";
-	pr_info("Machine: %s, model: %s\n", mdesc_best->name, model);
+	/* We really don't want to do this, but sometimes firmware provides buggy data */
+	if (mdesc->dt_fixup)
+		mdesc->dt_fixup();
 
-	/* Retrieve various information from the /chosen node */
-	of_scan_flat_dt(early_init_dt_scan_chosen, boot_command_line);
-	/* Initialize {size,address}-cells info */
-	of_scan_flat_dt(early_init_dt_scan_root, NULL);
-	/* Setup memory, calling early_init_dt_add_memory_arch */
-	of_scan_flat_dt(early_init_dt_scan_memory, NULL);
+	early_init_dt_scan_nodes();
 
 	/* Change machine number to match the mdesc we're using */
-	__machine_arch_type = mdesc_best->nr;
+	__machine_arch_type = mdesc->nr;
 
-	return mdesc_best;
+	return mdesc;
 }