1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * Procedures for creating, accessing and interpreting the device tree.
5 * Paul Mackerras August 1996.
6 * Copyright (C) 1996-2005 Paul Mackerras.
8 * Adapted for 64bit PowerPC by Dave Engebretsen and Peter Bergner.
9 * {engebret|bergner}@us.ibm.com
14 #include <linux/kernel.h>
15 #include <linux/string.h>
16 #include <linux/init.h>
17 #include <linux/threads.h>
18 #include <linux/spinlock.h>
19 #include <linux/types.h>
20 #include <linux/pci.h>
21 #include <linux/delay.h>
22 #include <linux/initrd.h>
23 #include <linux/bitops.h>
24 #include <linux/export.h>
25 #include <linux/kexec.h>
26 #include <linux/irq.h>
27 #include <linux/memblock.h>
29 #include <linux/of_fdt.h>
30 #include <linux/libfdt.h>
31 #include <linux/cpu.h>
32 #include <linux/pgtable.h>
33 #include <linux/seq_buf.h>
37 #include <asm/processor.h>
40 #include <asm/kdump.h>
44 #include <asm/powernv.h>
45 #include <asm/iommu.h>
46 #include <asm/btext.h>
47 #include <asm/sections.h>
48 #include <asm/setup.h>
49 #include <asm/pci-bridge.h>
50 #include <asm/kexec.h>
52 #include <asm/fadump.h>
53 #include <asm/epapr_hcalls.h>
54 #include <asm/firmware.h>
55 #include <asm/dt_cpu_ftrs.h>
56 #include <asm/drmem.h>
57 #include <asm/ultravisor.h>
60 #include <mm/mmu_decl.h>
63 #define DBG(fmt...) printk(KERN_ERR fmt)
68 int *chip_id_lookup_table;
71 int __initdata iommu_is_off;
72 int __initdata iommu_force_on;
73 unsigned long tce_alloc_start, tce_alloc_end;
75 unsigned int boot_cpu_node_count __ro_after_init;
77 static phys_addr_t first_memblock_size;
78 static int __initdata boot_cpu_count;
80 static int __init early_parse_mem(char *p)
85 memory_limit = PAGE_ALIGN(memparse(p, &p));
86 DBG("memory limit = 0x%llx\n", memory_limit);
90 early_param("mem", early_parse_mem);
93 * overlaps_initrd - check for overlap with page aligned extension of
96 static inline int overlaps_initrd(unsigned long start, unsigned long size)
98 #ifdef CONFIG_BLK_DEV_INITRD
102 return (start + size) > ALIGN_DOWN(initrd_start, PAGE_SIZE) &&
103 start <= ALIGN(initrd_end, PAGE_SIZE);
110 * move_device_tree - move tree to an unused area, if needed.
112 * The device tree may be allocated beyond our memory limit, or inside the
113 * crash kernel region for kdump, or within the page aligned range of initrd.
114 * If so, move it out of the way.
116 static void __init move_device_tree(void)
118 unsigned long start, size;
121 DBG("-> move_device_tree\n");
123 start = __pa(initial_boot_params);
124 size = fdt_totalsize(initial_boot_params);
126 if ((memory_limit && (start + size) > PHYSICAL_START + memory_limit) ||
127 !memblock_is_memory(start + size - 1) ||
128 overlaps_crashkernel(start, size) || overlaps_initrd(start, size)) {
129 p = memblock_alloc_raw(size, PAGE_SIZE);
131 panic("Failed to allocate %lu bytes to move device tree\n",
133 memcpy(p, initial_boot_params, size);
134 initial_boot_params = p;
135 DBG("Moved device tree to 0x%px\n", p);
138 DBG("<- move_device_tree\n");
142 * ibm,pa/pi-features is a per-cpu property that contains a string of
143 * attribute descriptors, each of which has a 2 byte header plus up
144 * to 254 bytes worth of processor attribute bits. First header
145 * byte specifies the number of bytes following the header.
146 * Second header byte is an "attribute-specifier" type, of which
147 * zero is the only currently-defined value.
148 * Implementation: Pass in the byte and bit offset for the feature
149 * that we are interested in. The function will return -1 if the
150 * pa-features property is missing, or a 1/0 to indicate if the feature
151 * is supported/not supported. Note that the bit numbers are
152 * big-endian to match the definition in PAPR.
155 unsigned long cpu_features; /* CPU_FTR_xxx bit */
156 unsigned long mmu_features; /* MMU_FTR_xxx bit */
157 unsigned int cpu_user_ftrs; /* PPC_FEATURE_xxx bit */
158 unsigned int cpu_user_ftrs2; /* PPC_FEATURE2_xxx bit */
159 unsigned char pabyte; /* byte number in ibm,pa/pi-features */
160 unsigned char pabit; /* bit number (big-endian) */
161 unsigned char invert; /* if 1, pa bit set => clear feature */
164 static struct ibm_feature ibm_pa_features[] __initdata = {
165 { .pabyte = 0, .pabit = 0, .cpu_user_ftrs = PPC_FEATURE_HAS_MMU },
166 { .pabyte = 0, .pabit = 1, .cpu_user_ftrs = PPC_FEATURE_HAS_FPU },
167 { .pabyte = 0, .pabit = 3, .cpu_features = CPU_FTR_CTRL },
168 { .pabyte = 0, .pabit = 6, .cpu_features = CPU_FTR_NOEXECUTE },
169 { .pabyte = 1, .pabit = 2, .mmu_features = MMU_FTR_CI_LARGE_PAGE },
170 #ifdef CONFIG_PPC_RADIX_MMU
171 { .pabyte = 40, .pabit = 0, .mmu_features = MMU_FTR_TYPE_RADIX | MMU_FTR_GTSE },
173 { .pabyte = 5, .pabit = 0, .cpu_features = CPU_FTR_REAL_LE,
174 .cpu_user_ftrs = PPC_FEATURE_TRUE_LE },
176 * If the kernel doesn't support TM (ie CONFIG_PPC_TRANSACTIONAL_MEM=n),
177 * we don't want to turn on TM here, so we use the *_COMP versions
178 * which are 0 if the kernel doesn't support TM.
180 { .pabyte = 22, .pabit = 0, .cpu_features = CPU_FTR_TM_COMP,
181 .cpu_user_ftrs2 = PPC_FEATURE2_HTM_COMP | PPC_FEATURE2_HTM_NOSC_COMP },
183 { .pabyte = 64, .pabit = 0, .cpu_features = CPU_FTR_DAWR1 },
187 * ibm,pi-features property provides the support of processor specific
188 * options not described in ibm,pa-features. Right now use byte 0, bit 3
189 * which indicates the occurrence of DSI interrupt when the paste operation
190 * on the suspended NX window.
192 static struct ibm_feature ibm_pi_features[] __initdata = {
193 { .pabyte = 0, .pabit = 3, .mmu_features = MMU_FTR_NX_DSI },
196 static void __init scan_features(unsigned long node, const unsigned char *ftrs,
197 unsigned long tablelen,
198 struct ibm_feature *fp,
199 unsigned long ft_size)
201 unsigned long i, len, bit;
203 /* find descriptor with type == 0 */
209 return; /* descriptor 0 not found */
216 /* loop over bits we know about */
217 for (i = 0; i < ft_size; ++i, ++fp) {
218 if (fp->pabyte >= ftrs[0])
220 bit = (ftrs[2 + fp->pabyte] >> (7 - fp->pabit)) & 1;
221 if (bit ^ fp->invert) {
222 cur_cpu_spec->cpu_features |= fp->cpu_features;
223 cur_cpu_spec->cpu_user_features |= fp->cpu_user_ftrs;
224 cur_cpu_spec->cpu_user_features2 |= fp->cpu_user_ftrs2;
225 cur_cpu_spec->mmu_features |= fp->mmu_features;
227 cur_cpu_spec->cpu_features &= ~fp->cpu_features;
228 cur_cpu_spec->cpu_user_features &= ~fp->cpu_user_ftrs;
229 cur_cpu_spec->cpu_user_features2 &= ~fp->cpu_user_ftrs2;
230 cur_cpu_spec->mmu_features &= ~fp->mmu_features;
235 static void __init check_cpu_features(unsigned long node, char *name,
236 struct ibm_feature *fp,
239 const unsigned char *pa_ftrs;
242 pa_ftrs = of_get_flat_dt_prop(node, name, &tablelen);
246 scan_features(node, pa_ftrs, tablelen, fp, size);
249 #ifdef CONFIG_PPC_64S_HASH_MMU
250 static void __init init_mmu_slb_size(unsigned long node)
252 const __be32 *slb_size_ptr;
254 slb_size_ptr = of_get_flat_dt_prop(node, "slb-size", NULL) ? :
255 of_get_flat_dt_prop(node, "ibm,slb-size", NULL);
258 mmu_slb_size = be32_to_cpup(slb_size_ptr);
261 #define init_mmu_slb_size(node) do { } while(0)
264 static struct feature_property {
267 unsigned long cpu_feature;
268 unsigned long cpu_user_ftr;
269 } feature_properties[] __initdata = {
270 #ifdef CONFIG_ALTIVEC
271 {"altivec", 0, CPU_FTR_ALTIVEC, PPC_FEATURE_HAS_ALTIVEC},
272 {"ibm,vmx", 1, CPU_FTR_ALTIVEC, PPC_FEATURE_HAS_ALTIVEC},
273 #endif /* CONFIG_ALTIVEC */
275 /* Yes, this _really_ is ibm,vmx == 2 to enable VSX */
276 {"ibm,vmx", 2, CPU_FTR_VSX, PPC_FEATURE_HAS_VSX},
277 #endif /* CONFIG_VSX */
279 {"ibm,dfp", 1, 0, PPC_FEATURE_HAS_DFP},
280 {"ibm,purr", 1, CPU_FTR_PURR, 0},
281 {"ibm,spurr", 1, CPU_FTR_SPURR, 0},
282 #endif /* CONFIG_PPC64 */
285 #if defined(CONFIG_44x) && defined(CONFIG_PPC_FPU)
286 static __init void identical_pvr_fixup(unsigned long node)
289 const char *model = of_get_flat_dt_prop(node, "model", NULL);
292 * Since 440GR(x)/440EP(x) processors have the same pvr,
293 * we check the node path and set bit 28 in the cur_cpu_spec
294 * pvr for EP(x) processor version. This bit is always 0 in
295 * the "real" pvr. Then we call identify_cpu again with
296 * the new logical pvr to enable FPU support.
298 if (model && strstr(model, "440EP")) {
299 pvr = cur_cpu_spec->pvr_value | 0x8;
300 identify_cpu(0, pvr);
301 DBG("Using logical pvr %x for %s\n", pvr, model);
305 #define identical_pvr_fixup(node) do { } while(0)
308 static void __init check_cpu_feature_properties(unsigned long node)
311 struct feature_property *fp = feature_properties;
314 for (i = 0; i < (int)ARRAY_SIZE(feature_properties); ++i, ++fp) {
315 prop = of_get_flat_dt_prop(node, fp->name, NULL);
316 if (prop && be32_to_cpup(prop) >= fp->min_value) {
317 cur_cpu_spec->cpu_features |= fp->cpu_feature;
318 cur_cpu_spec->cpu_user_features |= fp->cpu_user_ftr;
323 static int __init early_init_dt_scan_cpus(unsigned long node,
324 const char *uname, int depth,
327 const char *type = of_get_flat_dt_prop(node, "device_type", NULL);
329 const __be32 *intserv;
333 int found_thread = 0;
335 /* We are scanning "cpu" nodes only */
336 if (type == NULL || strcmp(type, "cpu") != 0)
339 if (IS_ENABLED(CONFIG_PPC64))
340 boot_cpu_node_count++;
342 /* Get physical cpuid */
343 intserv = of_get_flat_dt_prop(node, "ibm,ppc-interrupt-server#s", &len);
345 intserv = of_get_flat_dt_prop(node, "reg", &len);
347 nthreads = len / sizeof(int);
350 * Now see if any of these threads match our boot cpu.
351 * NOTE: This must match the parsing done in smp_setup_cpu_maps.
353 for (i = 0; i < nthreads; i++) {
354 if (be32_to_cpu(intserv[i]) ==
355 fdt_boot_cpuid_phys(initial_boot_params)) {
356 found = boot_cpu_count;
360 /* logical cpu id is always 0 on UP kernels */
365 /* Not the boot CPU */
369 DBG("boot cpu: logical %d physical %d\n", found,
370 be32_to_cpu(intserv[found_thread]));
373 // Pass the boot CPU's hard CPU id back to our caller
374 *((u32 *)data) = be32_to_cpu(intserv[found_thread]);
377 * PAPR defines "logical" PVR values for cpus that
378 * meet various levels of the architecture:
379 * 0x0f000001 Architecture version 2.04
380 * 0x0f000002 Architecture version 2.05
381 * If the cpu-version property in the cpu node contains
382 * such a value, we call identify_cpu again with the
383 * logical PVR value in order to use the cpu feature
384 * bits appropriate for the architecture level.
386 * A POWER6 partition in "POWER6 architected" mode
387 * uses the 0x0f000002 PVR value; in POWER5+ mode
388 * it uses 0x0f000001.
390 * If we're using device tree CPU feature discovery then we don't
391 * support the cpu-version property, and it's the responsibility of the
392 * firmware/hypervisor to provide the correct feature set for the
393 * architecture level via the ibm,powerpc-cpu-features binding.
395 if (!dt_cpu_ftrs_in_use()) {
396 prop = of_get_flat_dt_prop(node, "cpu-version", NULL);
397 if (prop && (be32_to_cpup(prop) & 0xff000000) == 0x0f000000) {
398 identify_cpu(0, be32_to_cpup(prop));
399 seq_buf_printf(&ppc_hw_desc, "0x%04x ", be32_to_cpup(prop));
402 check_cpu_feature_properties(node);
403 check_cpu_features(node, "ibm,pa-features", ibm_pa_features,
404 ARRAY_SIZE(ibm_pa_features));
405 check_cpu_features(node, "ibm,pi-features", ibm_pi_features,
406 ARRAY_SIZE(ibm_pi_features));
409 identical_pvr_fixup(node);
410 init_mmu_slb_size(node);
414 cur_cpu_spec->cpu_features &= ~CPU_FTR_SMT;
415 else if (!dt_cpu_ftrs_in_use())
416 cur_cpu_spec->cpu_features |= CPU_FTR_SMT;
422 static int __init early_init_dt_scan_chosen_ppc(unsigned long node,
424 int depth, void *data)
426 const unsigned long *lprop; /* All these set by kernel, so no need to convert endian */
428 /* Use common scan routine to determine if this is the chosen node */
429 if (early_init_dt_scan_chosen(data) < 0)
433 /* check if iommu is forced on or off */
434 if (of_get_flat_dt_prop(node, "linux,iommu-off", NULL) != NULL)
436 if (of_get_flat_dt_prop(node, "linux,iommu-force-on", NULL) != NULL)
440 /* mem=x on the command line is the preferred mechanism */
441 lprop = of_get_flat_dt_prop(node, "linux,memory-limit", NULL);
443 memory_limit = *lprop;
446 lprop = of_get_flat_dt_prop(node, "linux,tce-alloc-start", NULL);
448 tce_alloc_start = *lprop;
449 lprop = of_get_flat_dt_prop(node, "linux,tce-alloc-end", NULL);
451 tce_alloc_end = *lprop;
454 #ifdef CONFIG_KEXEC_CORE
455 lprop = of_get_flat_dt_prop(node, "linux,crashkernel-base", NULL);
457 crashk_res.start = *lprop;
459 lprop = of_get_flat_dt_prop(node, "linux,crashkernel-size", NULL);
461 crashk_res.end = crashk_res.start + *lprop - 1;
469 * Compare the range against max mem limit and update
470 * size if it cross the limit.
473 #ifdef CONFIG_SPARSEMEM
474 static bool __init validate_mem_limit(u64 base, u64 *size)
476 u64 max_mem = 1UL << (MAX_PHYSMEM_BITS);
480 if ((base + *size) > max_mem)
481 *size = max_mem - base;
485 static bool __init validate_mem_limit(u64 base, u64 *size)
491 #ifdef CONFIG_PPC_PSERIES
493 * Interpret the ibm dynamic reconfiguration memory LMBs.
494 * This contains a list of memory blocks along with NUMA affinity
497 static int __init early_init_drmem_lmb(struct drmem_lmb *lmb,
502 int is_kexec_kdump = 0, rngs;
504 base = lmb->base_addr;
505 size = drmem_lmb_size();
509 * Skip this block if the reserved bit is set in flags
510 * or if the block is not assigned to this partition.
512 if ((lmb->flags & DRCONF_MEM_RESERVED) ||
513 !(lmb->flags & DRCONF_MEM_ASSIGNED))
519 if (is_kexec_kdump) {
521 * For each memblock in ibm,dynamic-memory, a
522 * corresponding entry in linux,drconf-usable-memory
523 * property contains a counter 'p' followed by 'p'
524 * (base, size) duple. Now read the counter from
525 * linux,drconf-usable-memory property
527 rngs = dt_mem_next_cell(dt_root_size_cells, usm);
528 if (!rngs) /* there are no (base, size) duple */
533 if (is_kexec_kdump) {
534 base = dt_mem_next_cell(dt_root_addr_cells, usm);
535 size = dt_mem_next_cell(dt_root_size_cells, usm);
539 if (base >= 0x80000000ul)
541 if ((base + size) > 0x80000000ul)
542 size = 0x80000000ul - base;
545 if (!validate_mem_limit(base, &size))
548 DBG("Adding: %llx -> %llx\n", base, size);
549 memblock_add(base, size);
551 if (lmb->flags & DRCONF_MEM_HOTREMOVABLE)
552 memblock_mark_hotplug(base, size);
557 #endif /* CONFIG_PPC_PSERIES */
559 static int __init early_init_dt_scan_memory_ppc(void)
561 #ifdef CONFIG_PPC_PSERIES
562 const void *fdt = initial_boot_params;
563 int node = fdt_path_offset(fdt, "/ibm,dynamic-reconfiguration-memory");
566 walk_drmem_lmbs_early(node, NULL, early_init_drmem_lmb);
570 return early_init_dt_scan_memory();
574 * For a relocatable kernel, we need to get the memstart_addr first,
575 * then use it to calculate the virtual kernel start address. This has
576 * to happen at a very early stage (before machine_init). In this case,
577 * we just want to get the memstart_address and would not like to mess the
578 * memblock at this stage. So introduce a variable to skip the memblock_add()
581 #ifdef CONFIG_RELOCATABLE
582 static int add_mem_to_memblock = 1;
584 #define add_mem_to_memblock 1
587 void __init early_init_dt_add_memory_arch(u64 base, u64 size)
591 if (base >= 0x80000000ul)
593 if ((base + size) > 0x80000000ul)
594 size = 0x80000000ul - base;
597 /* Keep track of the beginning of memory -and- the size of
598 * the very first block in the device-tree as it represents
599 * the RMA on ppc64 server
601 if (base < memstart_addr) {
602 memstart_addr = base;
603 first_memblock_size = size;
606 /* Add the chunk to the MEMBLOCK list */
607 if (add_mem_to_memblock) {
608 if (validate_mem_limit(base, &size))
609 memblock_add(base, size);
613 static void __init early_reserve_mem_dt(void)
615 unsigned long i, dt_root;
619 early_init_fdt_reserve_self();
620 early_init_fdt_scan_reserved_mem();
622 dt_root = of_get_flat_dt_root();
624 prop = of_get_flat_dt_prop(dt_root, "reserved-ranges", &len);
629 DBG("Found new-style reserved-ranges\n");
631 /* Each reserved range is an (address,size) pair, 2 cells each,
632 * totalling 4 cells per range. */
633 for (i = 0; i < len / (sizeof(*prop) * 4); i++) {
636 base = of_read_number(prop + (i * 4) + 0, 2);
637 size = of_read_number(prop + (i * 4) + 2, 2);
640 DBG("reserving: %llx -> %llx\n", base, size);
641 memblock_reserve(base, size);
646 static void __init early_reserve_mem(void)
650 reserve_map = (__be64 *)(((unsigned long)initial_boot_params) +
651 fdt_off_mem_rsvmap(initial_boot_params));
653 /* Look for the new "reserved-regions" property in the DT */
654 early_reserve_mem_dt();
656 #ifdef CONFIG_BLK_DEV_INITRD
657 /* Then reserve the initrd, if any */
658 if (initrd_start && (initrd_end > initrd_start)) {
659 memblock_reserve(ALIGN_DOWN(__pa(initrd_start), PAGE_SIZE),
660 ALIGN(initrd_end, PAGE_SIZE) -
661 ALIGN_DOWN(initrd_start, PAGE_SIZE));
663 #endif /* CONFIG_BLK_DEV_INITRD */
665 if (!IS_ENABLED(CONFIG_PPC32))
669 * Handle the case where we might be booting from an old kexec
670 * image that setup the mem_rsvmap as pairs of 32-bit values
672 if (be64_to_cpup(reserve_map) > 0xffffffffull) {
673 u32 base_32, size_32;
674 __be32 *reserve_map_32 = (__be32 *)reserve_map;
676 DBG("Found old 32-bit reserve map\n");
679 base_32 = be32_to_cpup(reserve_map_32++);
680 size_32 = be32_to_cpup(reserve_map_32++);
683 DBG("reserving: %x -> %x\n", base_32, size_32);
684 memblock_reserve(base_32, size_32);
690 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
691 static bool tm_disabled __initdata;
693 static int __init parse_ppc_tm(char *str)
697 if (kstrtobool(str, &res))
704 early_param("ppc_tm", parse_ppc_tm);
706 static void __init tm_init(void)
709 pr_info("Disabling hardware transactional memory (HTM)\n");
710 cur_cpu_spec->cpu_user_features2 &=
711 ~(PPC_FEATURE2_HTM_NOSC | PPC_FEATURE2_HTM);
712 cur_cpu_spec->cpu_features &= ~CPU_FTR_TM;
719 static void tm_init(void) { }
720 #endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
723 early_init_dt_scan_model(unsigned long node, const char *uname,
724 int depth, void *data)
731 prop = of_get_flat_dt_prop(node, "model", NULL);
733 seq_buf_printf(&ppc_hw_desc, "%s ", prop);
740 static void __init save_fscr_to_task(void)
743 * Ensure the init_task (pid 0, aka swapper) uses the value of FSCR we
744 * have configured via the device tree features or via __init_FSCR().
745 * That value will then be propagated to pid 1 (init) and all future
748 if (early_cpu_has_feature(CPU_FTR_ARCH_207S))
749 init_task.thread.fscr = mfspr(SPRN_FSCR);
752 static inline void save_fscr_to_task(void) {}
756 void __init early_init_devtree(void *params)
761 DBG(" -> early_init_devtree(%px)\n", params);
763 /* Too early to BUG_ON(), do it by hand */
764 if (!early_init_dt_verify(params))
765 panic("BUG: Failed verifying flat device tree, bad version?");
767 of_scan_flat_dt(early_init_dt_scan_model, NULL);
769 #ifdef CONFIG_PPC_RTAS
770 /* Some machines might need RTAS info for debugging, grab it now. */
771 of_scan_flat_dt(early_init_dt_scan_rtas, NULL);
774 #ifdef CONFIG_PPC_POWERNV
775 /* Some machines might need OPAL info for debugging, grab it now. */
776 of_scan_flat_dt(early_init_dt_scan_opal, NULL);
778 /* Scan tree for ultravisor feature */
779 of_scan_flat_dt(early_init_dt_scan_ultravisor, NULL);
782 #if defined(CONFIG_FA_DUMP) || defined(CONFIG_PRESERVE_FA_DUMP)
783 /* scan tree to see if dump is active during last boot */
784 of_scan_flat_dt(early_init_dt_scan_fw_dump, NULL);
787 /* Retrieve various informations from the /chosen node of the
788 * device-tree, including the platform type, initrd location and
789 * size, TCE reserve, and more ...
791 of_scan_flat_dt(early_init_dt_scan_chosen_ppc, boot_command_line);
793 /* Scan memory nodes and rebuild MEMBLOCKs */
794 early_init_dt_scan_root();
795 early_init_dt_scan_memory_ppc();
798 * As generic code authors expect to be able to use static keys
799 * in early_param() handlers, we initialize the static keys just
800 * before parsing early params (it's fine to call jump_label_init()
806 /* make sure we've parsed cmdline for mem= before this */
808 first_memblock_size = min_t(u64, first_memblock_size, memory_limit);
809 setup_initial_memory_limit(memstart_addr, first_memblock_size);
810 /* Reserve MEMBLOCK regions used by kernel, initrd, dt, etc... */
811 memblock_reserve(PHYSICAL_START, __pa(_end) - PHYSICAL_START);
812 /* If relocatable, reserve first 32k for interrupt vectors etc. */
813 if (PHYSICAL_START > MEMORY_START)
814 memblock_reserve(MEMORY_START, 0x8000);
815 reserve_kdump_trampoline();
816 #if defined(CONFIG_FA_DUMP) || defined(CONFIG_PRESERVE_FA_DUMP)
818 * If we fail to reserve memory for firmware-assisted dump then
819 * fallback to kexec based kdump.
821 if (fadump_reserve_mem() == 0)
823 reserve_crashkernel();
826 /* Ensure that total memory size is page-aligned. */
827 limit = ALIGN(memory_limit ?: memblock_phys_mem_size(), PAGE_SIZE);
828 memblock_enforce_memory_limit(limit);
830 #if defined(CONFIG_PPC_BOOK3S_64) && defined(CONFIG_PPC_4K_PAGES)
831 if (!early_radix_enabled())
832 memblock_cap_memory_range(0, 1UL << (H_MAX_PHYSMEM_BITS));
835 memblock_allow_resize();
838 DBG("Phys. mem: %llx\n", (unsigned long long)memblock_phys_mem_size());
840 /* We may need to relocate the flat tree, do it now.
841 * FIXME .. and the initrd too? */
844 DBG("Scanning CPUs ...\n");
848 // We can now add the CPU name & PVR to the hardware description
849 seq_buf_printf(&ppc_hw_desc, "%s 0x%04lx ", cur_cpu_spec->cpu_name, mfspr(SPRN_PVR));
851 /* Retrieve CPU related informations from the flat tree
852 * (altivec support, boot CPU ID, ...)
854 of_scan_flat_dt(early_init_dt_scan_cpus, &boot_cpu_hwid);
855 if (boot_cpuid < 0) {
856 printk("Failed to identify boot CPU !\n");
862 #if defined(CONFIG_SMP) && defined(CONFIG_PPC64)
863 /* We'll later wait for secondaries to check in; there are
864 * NCPUS-1 non-boot CPUs :-)
866 spinning_secondaries = boot_cpu_count - 1;
869 mmu_early_init_devtree();
871 // NB. paca is not installed until later in early_setup()
872 allocate_paca_ptrs();
873 allocate_paca(boot_cpuid);
874 set_hard_smp_processor_id(boot_cpuid, boot_cpu_hwid);
876 #ifdef CONFIG_PPC_POWERNV
877 /* Scan and build the list of machine check recoverable ranges */
878 of_scan_flat_dt(early_init_dt_scan_recoverable_ranges, NULL);
880 epapr_paravirt_early_init();
882 /* Now try to figure out if we are running on LPAR and so on */
883 pseries_probe_fw_features();
886 * Initialize pkey features and default AMR/IAMR values
888 pkey_early_init_devtree();
890 #ifdef CONFIG_PPC_PS3
891 /* Identify PS3 firmware */
892 if (of_flat_dt_is_compatible(of_get_flat_dt_root(), "sony,ps3"))
893 powerpc_firmware_features |= FW_FEATURE_PS3_POSSIBLE;
898 DBG(" <- early_init_devtree()\n");
901 #ifdef CONFIG_RELOCATABLE
903 * This function run before early_init_devtree, so we have to init
904 * initial_boot_params.
906 void __init early_get_first_memblock_info(void *params, phys_addr_t *size)
908 /* Setup flat device-tree pointer */
909 initial_boot_params = params;
912 * Scan the memory nodes and set add_mem_to_memblock to 0 to avoid
915 add_mem_to_memblock = 0;
916 early_init_dt_scan_root();
917 early_init_dt_scan_memory_ppc();
918 add_mem_to_memblock = 1;
921 *size = first_memblock_size;
927 * New implementation of the OF "find" APIs, return a refcounted
928 * object, call of_node_put() when done. The device tree and list
929 * are protected by a rw_lock.
931 * Note that property management will need some locking as well,
932 * this isn't dealt with yet.
937 * of_get_ibm_chip_id - Returns the IBM "chip-id" of a device
938 * @np: device node of the device
940 * This looks for a property "ibm,chip-id" in the node or any
941 * of its parents and returns its content, or -1 if it cannot
944 int of_get_ibm_chip_id(struct device_node *np)
951 * Skiboot may produce memory nodes that contain more than one
952 * cell in chip-id, we only read the first one here.
954 if (!of_property_read_u32(np, "ibm,chip-id", &chip_id)) {
959 np = of_get_next_parent(np);
963 EXPORT_SYMBOL(of_get_ibm_chip_id);
966 * cpu_to_chip_id - Return the cpus chip-id
967 * @cpu: The logical cpu number.
969 * Return the value of the ibm,chip-id property corresponding to the given
970 * logical cpu number. If the chip-id can not be found, returns -1.
972 int cpu_to_chip_id(int cpu)
974 struct device_node *np;
977 idx = cpu / threads_per_core;
978 if (chip_id_lookup_table && chip_id_lookup_table[idx] != -1)
979 return chip_id_lookup_table[idx];
981 np = of_get_cpu_node(cpu, NULL);
983 ret = of_get_ibm_chip_id(np);
986 if (chip_id_lookup_table)
987 chip_id_lookup_table[idx] = ret;
992 EXPORT_SYMBOL(cpu_to_chip_id);
994 bool arch_match_cpu_phys_id(int cpu, u64 phys_id)
998 * Early firmware scanning must use this rather than
999 * get_hard_smp_processor_id because we don't have pacas allocated
1000 * until memory topology is discovered.
1002 if (cpu_to_phys_id != NULL)
1003 return (int)phys_id == cpu_to_phys_id[cpu];
1006 return (int)phys_id == get_hard_smp_processor_id(cpu);