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  1/*
  2 *  linux/arch/arm/kernel/devtree.c
  3 *
  4 *  Copyright (C) 2009 Canonical Ltd. <jeremy.kerr@canonical.com>
  5 *
  6 * This program is free software; you can redistribute it and/or modify
  7 * it under the terms of the GNU General Public License version 2 as
  8 * published by the Free Software Foundation.
  9 */
 10
 11#include <linux/init.h>
 12#include <linux/export.h>
 13#include <linux/errno.h>
 14#include <linux/types.h>
 15#include <linux/bootmem.h>
 16#include <linux/memblock.h>
 17#include <linux/of.h>
 18#include <linux/of_fdt.h>
 19#include <linux/of_irq.h>
 20#include <linux/of_platform.h>
 21#include <linux/smp.h>
 22
 23#include <asm/cputype.h>
 24#include <asm/setup.h>
 25#include <asm/page.h>
 26#include <asm/prom.h>
 27#include <asm/smp_plat.h>
 28#include <asm/mach/arch.h>
 29#include <asm/mach-types.h>
 30
 
 
 
 
 31
 32#ifdef CONFIG_SMP
 33extern struct of_cpu_method __cpu_method_of_table[];
 
 
 
 
 
 
 
 
 
 
 
 
 
 34
 35static const struct of_cpu_method __cpu_method_of_table_sentinel
 36	__used __section(__cpu_method_of_table_end);
 
 
 
 
 
 
 
 
 
 
 
 
 
 37
 
 
 
 38
 39static int __init set_smp_ops_by_method(struct device_node *node)
 40{
 41	const char *method;
 42	struct of_cpu_method *m = __cpu_method_of_table;
 43
 44	if (of_property_read_string(node, "enable-method", &method))
 45		return 0;
 46
 47	for (; m->method; m++)
 48		if (!strcmp(m->method, method)) {
 49			smp_set_ops(m->ops);
 50			return 1;
 51		}
 52
 53	return 0;
 54}
 55#else
 56static inline int set_smp_ops_by_method(struct device_node *node)
 57{
 58	return 1;
 59}
 60#endif
 61
 62
 63/*
 64 * arm_dt_init_cpu_maps - Function retrieves cpu nodes from the device tree
 65 * and builds the cpu logical map array containing MPIDR values related to
 66 * logical cpus
 67 *
 68 * Updates the cpu possible mask with the number of parsed cpu nodes
 69 */
 70void __init arm_dt_init_cpu_maps(void)
 71{
 72	/*
 73	 * Temp logical map is initialized with UINT_MAX values that are
 74	 * considered invalid logical map entries since the logical map must
 75	 * contain a list of MPIDR[23:0] values where MPIDR[31:24] must
 76	 * read as 0.
 77	 */
 78	struct device_node *cpu, *cpus;
 79	int found_method = 0;
 80	u32 i, j, cpuidx = 1;
 81	u32 mpidr = is_smp() ? read_cpuid_mpidr() & MPIDR_HWID_BITMASK : 0;
 82
 83	u32 tmp_map[NR_CPUS] = { [0 ... NR_CPUS-1] = MPIDR_INVALID };
 84	bool bootcpu_valid = false;
 85	cpus = of_find_node_by_path("/cpus");
 86
 87	if (!cpus)
 88		return;
 89
 90	for_each_child_of_node(cpus, cpu) {
 91		const __be32 *cell;
 92		int prop_bytes;
 93		u32 hwid;
 94
 95		if (of_node_cmp(cpu->type, "cpu"))
 96			continue;
 97
 98		pr_debug(" * %s...\n", cpu->full_name);
 99		/*
100		 * A device tree containing CPU nodes with missing "reg"
101		 * properties is considered invalid to build the
102		 * cpu_logical_map.
103		 */
104		cell = of_get_property(cpu, "reg", &prop_bytes);
105		if (!cell || prop_bytes < sizeof(*cell)) {
106			pr_debug(" * %s missing reg property\n",
107				     cpu->full_name);
108			of_node_put(cpu);
109			return;
110		}
111
112		/*
113		 * Bits n:24 must be set to 0 in the DT since the reg property
114		 * defines the MPIDR[23:0].
115		 */
116		do {
117			hwid = be32_to_cpu(*cell++);
118			prop_bytes -= sizeof(*cell);
119		} while (!hwid && prop_bytes > 0);
120
121		if (prop_bytes || (hwid & ~MPIDR_HWID_BITMASK)) {
122			of_node_put(cpu);
123			return;
124		}
125
126		/*
127		 * Duplicate MPIDRs are a recipe for disaster.
128		 * Scan all initialized entries and check for
129		 * duplicates. If any is found just bail out.
130		 * temp values were initialized to UINT_MAX
131		 * to avoid matching valid MPIDR[23:0] values.
132		 */
133		for (j = 0; j < cpuidx; j++)
134			if (WARN(tmp_map[j] == hwid,
135				 "Duplicate /cpu reg properties in the DT\n")) {
136				of_node_put(cpu);
137				return;
138			}
139
140		/*
141		 * Build a stashed array of MPIDR values. Numbering scheme
142		 * requires that if detected the boot CPU must be assigned
143		 * logical id 0. Other CPUs get sequential indexes starting
144		 * from 1. If a CPU node with a reg property matching the
145		 * boot CPU MPIDR is detected, this is recorded so that the
146		 * logical map built from DT is validated and can be used
147		 * to override the map created in smp_setup_processor_id().
148		 */
149		if (hwid == mpidr) {
150			i = 0;
151			bootcpu_valid = true;
152		} else {
153			i = cpuidx++;
154		}
155
156		if (WARN(cpuidx > nr_cpu_ids, "DT /cpu %u nodes greater than "
157					       "max cores %u, capping them\n",
158					       cpuidx, nr_cpu_ids)) {
159			cpuidx = nr_cpu_ids;
160			of_node_put(cpu);
161			break;
162		}
163
164		tmp_map[i] = hwid;
165
166		if (!found_method)
167			found_method = set_smp_ops_by_method(cpu);
168	}
169
170	/*
171	 * Fallback to an enable-method in the cpus node if nothing found in
172	 * a cpu node.
173	 */
174	if (!found_method)
175		set_smp_ops_by_method(cpus);
176
177	if (!bootcpu_valid) {
178		pr_warn("DT missing boot CPU MPIDR[23:0], fall back to default cpu_logical_map\n");
179		return;
180	}
181
182	/*
183	 * Since the boot CPU node contains proper data, and all nodes have
184	 * a reg property, the DT CPU list can be considered valid and the
185	 * logical map created in smp_setup_processor_id() can be overridden
186	 */
187	for (i = 0; i < cpuidx; i++) {
188		set_cpu_possible(i, true);
189		cpu_logical_map(i) = tmp_map[i];
190		pr_debug("cpu logical map 0x%x\n", cpu_logical_map(i));
191	}
192}
193
194bool arch_match_cpu_phys_id(int cpu, u64 phys_id)
195{
196	return phys_id == cpu_logical_map(cpu);
197}
198
199static const void * __init arch_get_next_mach(const char *const **match)
200{
201	static const struct machine_desc *mdesc = __arch_info_begin;
202	const struct machine_desc *m = mdesc;
203
204	if (m >= __arch_info_end)
205		return NULL;
206
207	mdesc++;
208	*match = m->dt_compat;
209	return m;
210}
211
212/**
213 * setup_machine_fdt - Machine setup when an dtb was passed to the kernel
214 * @dt_phys: physical address of dt blob
215 *
216 * If a dtb was passed to the kernel in r2, then use it to choose the
217 * correct machine_desc and to setup the system.
218 */
219const struct machine_desc * __init setup_machine_fdt(unsigned int dt_phys)
220{
221	const struct machine_desc *mdesc, *mdesc_best = NULL;
222
223#if defined(CONFIG_ARCH_MULTIPLATFORM) || defined(CONFIG_ARM_SINGLE_ARMV7M)
224	DT_MACHINE_START(GENERIC_DT, "Generic DT based system")
225		.l2c_aux_val = 0x0,
226		.l2c_aux_mask = ~0x0,
227	MACHINE_END
228
229	mdesc_best = &__mach_desc_GENERIC_DT;
230#endif
231
232	if (!dt_phys || !early_init_dt_verify(phys_to_virt(dt_phys)))
233		return NULL;
234
235	mdesc = of_flat_dt_match_machine(mdesc_best, arch_get_next_mach);
236
237	if (!mdesc) {
238		const char *prop;
239		int size;
240		unsigned long dt_root;
241
242		early_print("\nError: unrecognized/unsupported "
243			    "device tree compatible list:\n[ ");
244
245		dt_root = of_get_flat_dt_root();
246		prop = of_get_flat_dt_prop(dt_root, "compatible", &size);
247		while (size > 0) {
248			early_print("'%s' ", prop);
249			size -= strlen(prop) + 1;
250			prop += strlen(prop) + 1;
251		}
252		early_print("]\n\n");
253
254		dump_machine_table(); /* does not return */
255	}
256
257	/* We really don't want to do this, but sometimes firmware provides buggy data */
258	if (mdesc->dt_fixup)
259		mdesc->dt_fixup();
260
261	early_init_dt_scan_nodes();
262
263	/* Change machine number to match the mdesc we're using */
264	__machine_arch_type = mdesc->nr;
265
266	return mdesc;
267}
  1/*
  2 *  linux/arch/arm/kernel/devtree.c
  3 *
  4 *  Copyright (C) 2009 Canonical Ltd. <jeremy.kerr@canonical.com>
  5 *
  6 * This program is free software; you can redistribute it and/or modify
  7 * it under the terms of the GNU General Public License version 2 as
  8 * published by the Free Software Foundation.
  9 */
 10
 11#include <linux/init.h>
 12#include <linux/export.h>
 13#include <linux/errno.h>
 14#include <linux/types.h>
 15#include <linux/bootmem.h>
 16#include <linux/memblock.h>
 17#include <linux/of.h>
 18#include <linux/of_fdt.h>
 19#include <linux/of_irq.h>
 20#include <linux/of_platform.h>
 21#include <linux/smp.h>
 22
 23#include <asm/cputype.h>
 24#include <asm/setup.h>
 25#include <asm/page.h>
 
 26#include <asm/smp_plat.h>
 27#include <asm/mach/arch.h>
 28#include <asm/mach-types.h>
 29
 30void __init early_init_dt_add_memory_arch(u64 base, u64 size)
 31{
 32	arm_add_memory(base, size);
 33}
 34
 35void * __init early_init_dt_alloc_memory_arch(u64 size, u64 align)
 36{
 37	return memblock_virt_alloc(size, align);
 38}
 39
 40void __init arm_dt_memblock_reserve(void)
 41{
 42	u64 *reserve_map, base, size;
 43
 44	if (!initial_boot_params)
 45		return;
 46
 47	/* Reserve the dtb region */
 48	memblock_reserve(virt_to_phys(initial_boot_params),
 49			 be32_to_cpu(initial_boot_params->totalsize));
 50
 51	/*
 52	 * Process the reserve map.  This will probably overlap the initrd
 53	 * and dtb locations which are already reserved, but overlaping
 54	 * doesn't hurt anything
 55	 */
 56	reserve_map = ((void*)initial_boot_params) +
 57			be32_to_cpu(initial_boot_params->off_mem_rsvmap);
 58	while (1) {
 59		base = be64_to_cpup(reserve_map++);
 60		size = be64_to_cpup(reserve_map++);
 61		if (!size)
 62			break;
 63		memblock_reserve(base, size);
 64	}
 65}
 66
 67#ifdef CONFIG_SMP
 68extern struct of_cpu_method __cpu_method_of_table_begin[];
 69extern struct of_cpu_method __cpu_method_of_table_end[];
 70
 71static int __init set_smp_ops_by_method(struct device_node *node)
 72{
 73	const char *method;
 74	struct of_cpu_method *m = __cpu_method_of_table_begin;
 75
 76	if (of_property_read_string(node, "enable-method", &method))
 77		return 0;
 78
 79	for (; m < __cpu_method_of_table_end; m++)
 80		if (!strcmp(m->method, method)) {
 81			smp_set_ops(m->ops);
 82			return 1;
 83		}
 84
 85	return 0;
 86}
 87#else
 88static inline int set_smp_ops_by_method(struct device_node *node)
 89{
 90	return 1;
 91}
 92#endif
 93
 94
 95/*
 96 * arm_dt_init_cpu_maps - Function retrieves cpu nodes from the device tree
 97 * and builds the cpu logical map array containing MPIDR values related to
 98 * logical cpus
 99 *
100 * Updates the cpu possible mask with the number of parsed cpu nodes
101 */
102void __init arm_dt_init_cpu_maps(void)
103{
104	/*
105	 * Temp logical map is initialized with UINT_MAX values that are
106	 * considered invalid logical map entries since the logical map must
107	 * contain a list of MPIDR[23:0] values where MPIDR[31:24] must
108	 * read as 0.
109	 */
110	struct device_node *cpu, *cpus;
111	int found_method = 0;
112	u32 i, j, cpuidx = 1;
113	u32 mpidr = is_smp() ? read_cpuid_mpidr() & MPIDR_HWID_BITMASK : 0;
114
115	u32 tmp_map[NR_CPUS] = { [0 ... NR_CPUS-1] = MPIDR_INVALID };
116	bool bootcpu_valid = false;
117	cpus = of_find_node_by_path("/cpus");
118
119	if (!cpus)
120		return;
121
122	for_each_child_of_node(cpus, cpu) {
 
 
123		u32 hwid;
124
125		if (of_node_cmp(cpu->type, "cpu"))
126			continue;
127
128		pr_debug(" * %s...\n", cpu->full_name);
129		/*
130		 * A device tree containing CPU nodes with missing "reg"
131		 * properties is considered invalid to build the
132		 * cpu_logical_map.
133		 */
134		if (of_property_read_u32(cpu, "reg", &hwid)) {
 
135			pr_debug(" * %s missing reg property\n",
136				     cpu->full_name);
 
137			return;
138		}
139
140		/*
141		 * 8 MSBs must be set to 0 in the DT since the reg property
142		 * defines the MPIDR[23:0].
143		 */
144		if (hwid & ~MPIDR_HWID_BITMASK)
 
 
 
 
 
 
145			return;
 
146
147		/*
148		 * Duplicate MPIDRs are a recipe for disaster.
149		 * Scan all initialized entries and check for
150		 * duplicates. If any is found just bail out.
151		 * temp values were initialized to UINT_MAX
152		 * to avoid matching valid MPIDR[23:0] values.
153		 */
154		for (j = 0; j < cpuidx; j++)
155			if (WARN(tmp_map[j] == hwid, "Duplicate /cpu reg "
156						     "properties in the DT\n"))
 
157				return;
 
158
159		/*
160		 * Build a stashed array of MPIDR values. Numbering scheme
161		 * requires that if detected the boot CPU must be assigned
162		 * logical id 0. Other CPUs get sequential indexes starting
163		 * from 1. If a CPU node with a reg property matching the
164		 * boot CPU MPIDR is detected, this is recorded so that the
165		 * logical map built from DT is validated and can be used
166		 * to override the map created in smp_setup_processor_id().
167		 */
168		if (hwid == mpidr) {
169			i = 0;
170			bootcpu_valid = true;
171		} else {
172			i = cpuidx++;
173		}
174
175		if (WARN(cpuidx > nr_cpu_ids, "DT /cpu %u nodes greater than "
176					       "max cores %u, capping them\n",
177					       cpuidx, nr_cpu_ids)) {
178			cpuidx = nr_cpu_ids;
 
179			break;
180		}
181
182		tmp_map[i] = hwid;
183
184		if (!found_method)
185			found_method = set_smp_ops_by_method(cpu);
186	}
187
188	/*
189	 * Fallback to an enable-method in the cpus node if nothing found in
190	 * a cpu node.
191	 */
192	if (!found_method)
193		set_smp_ops_by_method(cpus);
194
195	if (!bootcpu_valid) {
196		pr_warn("DT missing boot CPU MPIDR[23:0], fall back to default cpu_logical_map\n");
197		return;
198	}
199
200	/*
201	 * Since the boot CPU node contains proper data, and all nodes have
202	 * a reg property, the DT CPU list can be considered valid and the
203	 * logical map created in smp_setup_processor_id() can be overridden
204	 */
205	for (i = 0; i < cpuidx; i++) {
206		set_cpu_possible(i, true);
207		cpu_logical_map(i) = tmp_map[i];
208		pr_debug("cpu logical map 0x%x\n", cpu_logical_map(i));
209	}
210}
211
212bool arch_match_cpu_phys_id(int cpu, u64 phys_id)
213{
214	return phys_id == cpu_logical_map(cpu);
215}
216
217static const void * __init arch_get_next_mach(const char *const **match)
218{
219	static const struct machine_desc *mdesc = __arch_info_begin;
220	const struct machine_desc *m = mdesc;
221
222	if (m >= __arch_info_end)
223		return NULL;
224
225	mdesc++;
226	*match = m->dt_compat;
227	return m;
228}
229
230/**
231 * setup_machine_fdt - Machine setup when an dtb was passed to the kernel
232 * @dt_phys: physical address of dt blob
233 *
234 * If a dtb was passed to the kernel in r2, then use it to choose the
235 * correct machine_desc and to setup the system.
236 */
237const struct machine_desc * __init setup_machine_fdt(unsigned int dt_phys)
238{
239	const struct machine_desc *mdesc, *mdesc_best = NULL;
240
241#ifdef CONFIG_ARCH_MULTIPLATFORM
242	DT_MACHINE_START(GENERIC_DT, "Generic DT based system")
 
 
243	MACHINE_END
244
245	mdesc_best = &__mach_desc_GENERIC_DT;
246#endif
247
248	if (!dt_phys || !early_init_dt_scan(phys_to_virt(dt_phys)))
249		return NULL;
250
251	mdesc = of_flat_dt_match_machine(mdesc_best, arch_get_next_mach);
252
253	if (!mdesc) {
254		const char *prop;
255		long size;
256		unsigned long dt_root;
257
258		early_print("\nError: unrecognized/unsupported "
259			    "device tree compatible list:\n[ ");
260
261		dt_root = of_get_flat_dt_root();
262		prop = of_get_flat_dt_prop(dt_root, "compatible", &size);
263		while (size > 0) {
264			early_print("'%s' ", prop);
265			size -= strlen(prop) + 1;
266			prop += strlen(prop) + 1;
267		}
268		early_print("]\n\n");
269
270		dump_machine_table(); /* does not return */
271	}
 
 
 
 
 
 
272
273	/* Change machine number to match the mdesc we're using */
274	__machine_arch_type = mdesc->nr;
275
276	return mdesc;
277}