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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /arch/powerpc/kernel/prom.c
Initial import
Diffstat (limited to 'arch/powerpc/kernel/prom.c')
-rw-r--r--arch/powerpc/kernel/prom.c827
1 files changed, 827 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/prom.c b/arch/powerpc/kernel/prom.c
new file mode 100644
index 000000000..308c5e156
--- /dev/null
+++ b/arch/powerpc/kernel/prom.c
@@ -0,0 +1,827 @@
+/*
+ * Procedures for creating, accessing and interpreting the device tree.
+ *
+ * Paul Mackerras August 1996.
+ * Copyright (C) 1996-2005 Paul Mackerras.
+ *
+ * Adapted for 64bit PowerPC by Dave Engebretsen and Peter Bergner.
+ * {engebret|bergner}@us.ibm.com
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#undef DEBUG
+
+#include <stdarg.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/init.h>
+#include <linux/threads.h>
+#include <linux/spinlock.h>
+#include <linux/types.h>
+#include <linux/pci.h>
+#include <linux/stringify.h>
+#include <linux/delay.h>
+#include <linux/initrd.h>
+#include <linux/bitops.h>
+#include <linux/export.h>
+#include <linux/kexec.h>
+#include <linux/irq.h>
+#include <linux/memblock.h>
+#include <linux/of.h>
+#include <linux/of_fdt.h>
+#include <linux/libfdt.h>
+
+#include <asm/prom.h>
+#include <asm/rtas.h>
+#include <asm/page.h>
+#include <asm/processor.h>
+#include <asm/irq.h>
+#include <asm/io.h>
+#include <asm/kdump.h>
+#include <asm/smp.h>
+#include <asm/mmu.h>
+#include <asm/paca.h>
+#include <asm/pgtable.h>
+#include <asm/pci.h>
+#include <asm/iommu.h>
+#include <asm/btext.h>
+#include <asm/sections.h>
+#include <asm/machdep.h>
+#include <asm/pci-bridge.h>
+#include <asm/kexec.h>
+#include <asm/opal.h>
+#include <asm/fadump.h>
+#include <asm/debug.h>
+
+#include <mm/mmu_decl.h>
+
+#ifdef DEBUG
+#define DBG(fmt...) printk(KERN_ERR fmt)
+#else
+#define DBG(fmt...)
+#endif
+
+#ifdef CONFIG_PPC64
+int __initdata iommu_is_off;
+int __initdata iommu_force_on;
+unsigned long tce_alloc_start, tce_alloc_end;
+u64 ppc64_rma_size;
+#endif
+static phys_addr_t first_memblock_size;
+static int __initdata boot_cpu_count;
+
+static int __init early_parse_mem(char *p)
+{
+ if (!p)
+ return 1;
+
+ memory_limit = PAGE_ALIGN(memparse(p, &p));
+ DBG("memory limit = 0x%llx\n", memory_limit);
+
+ return 0;
+}
+early_param("mem", early_parse_mem);
+
+/*
+ * overlaps_initrd - check for overlap with page aligned extension of
+ * initrd.
+ */
+static inline int overlaps_initrd(unsigned long start, unsigned long size)
+{
+#ifdef CONFIG_BLK_DEV_INITRD
+ if (!initrd_start)
+ return 0;
+
+ return (start + size) > _ALIGN_DOWN(initrd_start, PAGE_SIZE) &&
+ start <= _ALIGN_UP(initrd_end, PAGE_SIZE);
+#else
+ return 0;
+#endif
+}
+
+/**
+ * move_device_tree - move tree to an unused area, if needed.
+ *
+ * The device tree may be allocated beyond our memory limit, or inside the
+ * crash kernel region for kdump, or within the page aligned range of initrd.
+ * If so, move it out of the way.
+ */
+static void __init move_device_tree(void)
+{
+ unsigned long start, size;
+ void *p;
+
+ DBG("-> move_device_tree\n");
+
+ start = __pa(initial_boot_params);
+ size = fdt_totalsize(initial_boot_params);
+
+ if ((memory_limit && (start + size) > PHYSICAL_START + memory_limit) ||
+ overlaps_crashkernel(start, size) ||
+ overlaps_initrd(start, size)) {
+ p = __va(memblock_alloc(size, PAGE_SIZE));
+ memcpy(p, initial_boot_params, size);
+ initial_boot_params = p;
+ DBG("Moved device tree to 0x%p\n", p);
+ }
+
+ DBG("<- move_device_tree\n");
+}
+
+/*
+ * ibm,pa-features is a per-cpu property that contains a string of
+ * attribute descriptors, each of which has a 2 byte header plus up
+ * to 254 bytes worth of processor attribute bits. First header
+ * byte specifies the number of bytes following the header.
+ * Second header byte is an "attribute-specifier" type, of which
+ * zero is the only currently-defined value.
+ * Implementation: Pass in the byte and bit offset for the feature
+ * that we are interested in. The function will return -1 if the
+ * pa-features property is missing, or a 1/0 to indicate if the feature
+ * is supported/not supported. Note that the bit numbers are
+ * big-endian to match the definition in PAPR.
+ */
+static struct ibm_pa_feature {
+ unsigned long cpu_features; /* CPU_FTR_xxx bit */
+ unsigned long mmu_features; /* MMU_FTR_xxx bit */
+ unsigned int cpu_user_ftrs; /* PPC_FEATURE_xxx bit */
+ unsigned char pabyte; /* byte number in ibm,pa-features */
+ unsigned char pabit; /* bit number (big-endian) */
+ unsigned char invert; /* if 1, pa bit set => clear feature */
+} ibm_pa_features[] __initdata = {
+ {0, 0, PPC_FEATURE_HAS_MMU, 0, 0, 0},
+ {0, 0, PPC_FEATURE_HAS_FPU, 0, 1, 0},
+ {CPU_FTR_CTRL, 0, 0, 0, 3, 0},
+ {CPU_FTR_NOEXECUTE, 0, 0, 0, 6, 0},
+ {CPU_FTR_NODSISRALIGN, 0, 0, 1, 1, 1},
+ {0, MMU_FTR_CI_LARGE_PAGE, 0, 1, 2, 0},
+ {CPU_FTR_REAL_LE, PPC_FEATURE_TRUE_LE, 5, 0, 0},
+ /*
+ * If the kernel doesn't support TM (ie. CONFIG_PPC_TRANSACTIONAL_MEM=n),
+ * we don't want to turn on CPU_FTR_TM here, so we use CPU_FTR_TM_COMP
+ * which is 0 if the kernel doesn't support TM.
+ */
+ {CPU_FTR_TM_COMP, 0, 0, 22, 0, 0},
+};
+
+static void __init scan_features(unsigned long node, const unsigned char *ftrs,
+ unsigned long tablelen,
+ struct ibm_pa_feature *fp,
+ unsigned long ft_size)
+{
+ unsigned long i, len, bit;
+
+ /* find descriptor with type == 0 */
+ for (;;) {
+ if (tablelen < 3)
+ return;
+ len = 2 + ftrs[0];
+ if (tablelen < len)
+ return; /* descriptor 0 not found */
+ if (ftrs[1] == 0)
+ break;
+ tablelen -= len;
+ ftrs += len;
+ }
+
+ /* loop over bits we know about */
+ for (i = 0; i < ft_size; ++i, ++fp) {
+ if (fp->pabyte >= ftrs[0])
+ continue;
+ bit = (ftrs[2 + fp->pabyte] >> (7 - fp->pabit)) & 1;
+ if (bit ^ fp->invert) {
+ cur_cpu_spec->cpu_features |= fp->cpu_features;
+ cur_cpu_spec->cpu_user_features |= fp->cpu_user_ftrs;
+ cur_cpu_spec->mmu_features |= fp->mmu_features;
+ } else {
+ cur_cpu_spec->cpu_features &= ~fp->cpu_features;
+ cur_cpu_spec->cpu_user_features &= ~fp->cpu_user_ftrs;
+ cur_cpu_spec->mmu_features &= ~fp->mmu_features;
+ }
+ }
+}
+
+static void __init check_cpu_pa_features(unsigned long node)
+{
+ const unsigned char *pa_ftrs;
+ int tablelen;
+
+ pa_ftrs = of_get_flat_dt_prop(node, "ibm,pa-features", &tablelen);
+ if (pa_ftrs == NULL)
+ return;
+
+ scan_features(node, pa_ftrs, tablelen,
+ ibm_pa_features, ARRAY_SIZE(ibm_pa_features));
+}
+
+#ifdef CONFIG_PPC_STD_MMU_64
+static void __init check_cpu_slb_size(unsigned long node)
+{
+ const __be32 *slb_size_ptr;
+
+ slb_size_ptr = of_get_flat_dt_prop(node, "slb-size", NULL);
+ if (slb_size_ptr != NULL) {
+ mmu_slb_size = be32_to_cpup(slb_size_ptr);
+ return;
+ }
+ slb_size_ptr = of_get_flat_dt_prop(node, "ibm,slb-size", NULL);
+ if (slb_size_ptr != NULL) {
+ mmu_slb_size = be32_to_cpup(slb_size_ptr);
+ }
+}
+#else
+#define check_cpu_slb_size(node) do { } while(0)
+#endif
+
+static struct feature_property {
+ const char *name;
+ u32 min_value;
+ unsigned long cpu_feature;
+ unsigned long cpu_user_ftr;
+} feature_properties[] __initdata = {
+#ifdef CONFIG_ALTIVEC
+ {"altivec", 0, CPU_FTR_ALTIVEC, PPC_FEATURE_HAS_ALTIVEC},
+ {"ibm,vmx", 1, CPU_FTR_ALTIVEC, PPC_FEATURE_HAS_ALTIVEC},
+#endif /* CONFIG_ALTIVEC */
+#ifdef CONFIG_VSX
+ /* Yes, this _really_ is ibm,vmx == 2 to enable VSX */
+ {"ibm,vmx", 2, CPU_FTR_VSX, PPC_FEATURE_HAS_VSX},
+#endif /* CONFIG_VSX */
+#ifdef CONFIG_PPC64
+ {"ibm,dfp", 1, 0, PPC_FEATURE_HAS_DFP},
+ {"ibm,purr", 1, CPU_FTR_PURR, 0},
+ {"ibm,spurr", 1, CPU_FTR_SPURR, 0},
+#endif /* CONFIG_PPC64 */
+};
+
+#if defined(CONFIG_44x) && defined(CONFIG_PPC_FPU)
+static inline void identical_pvr_fixup(unsigned long node)
+{
+ unsigned int pvr;
+ const char *model = of_get_flat_dt_prop(node, "model", NULL);
+
+ /*
+ * Since 440GR(x)/440EP(x) processors have the same pvr,
+ * we check the node path and set bit 28 in the cur_cpu_spec
+ * pvr for EP(x) processor version. This bit is always 0 in
+ * the "real" pvr. Then we call identify_cpu again with
+ * the new logical pvr to enable FPU support.
+ */
+ if (model && strstr(model, "440EP")) {
+ pvr = cur_cpu_spec->pvr_value | 0x8;
+ identify_cpu(0, pvr);
+ DBG("Using logical pvr %x for %s\n", pvr, model);
+ }
+}
+#else
+#define identical_pvr_fixup(node) do { } while(0)
+#endif
+
+static void __init check_cpu_feature_properties(unsigned long node)
+{
+ unsigned long i;
+ struct feature_property *fp = feature_properties;
+ const __be32 *prop;
+
+ for (i = 0; i < ARRAY_SIZE(feature_properties); ++i, ++fp) {
+ prop = of_get_flat_dt_prop(node, fp->name, NULL);
+ if (prop && be32_to_cpup(prop) >= fp->min_value) {
+ cur_cpu_spec->cpu_features |= fp->cpu_feature;
+ cur_cpu_spec->cpu_user_features |= fp->cpu_user_ftr;
+ }
+ }
+}
+
+static int __init early_init_dt_scan_cpus(unsigned long node,
+ const char *uname, int depth,
+ void *data)
+{
+ const char *type = of_get_flat_dt_prop(node, "device_type", NULL);
+ const __be32 *prop;
+ const __be32 *intserv;
+ int i, nthreads;
+ int len;
+ int found = -1;
+ int found_thread = 0;
+
+ /* We are scanning "cpu" nodes only */
+ if (type == NULL || strcmp(type, "cpu") != 0)
+ return 0;
+
+ /* Get physical cpuid */
+ intserv = of_get_flat_dt_prop(node, "ibm,ppc-interrupt-server#s", &len);
+ if (!intserv)
+ intserv = of_get_flat_dt_prop(node, "reg", &len);
+
+ nthreads = len / sizeof(int);
+
+ /*
+ * Now see if any of these threads match our boot cpu.
+ * NOTE: This must match the parsing done in smp_setup_cpu_maps.
+ */
+ for (i = 0; i < nthreads; i++) {
+ /*
+ * version 2 of the kexec param format adds the phys cpuid of
+ * booted proc.
+ */
+ if (fdt_version(initial_boot_params) >= 2) {
+ if (be32_to_cpu(intserv[i]) ==
+ fdt_boot_cpuid_phys(initial_boot_params)) {
+ found = boot_cpu_count;
+ found_thread = i;
+ }
+ } else {
+ /*
+ * Check if it's the boot-cpu, set it's hw index now,
+ * unfortunately this format did not support booting
+ * off secondary threads.
+ */
+ if (of_get_flat_dt_prop(node,
+ "linux,boot-cpu", NULL) != NULL)
+ found = boot_cpu_count;
+ }
+#ifdef CONFIG_SMP
+ /* logical cpu id is always 0 on UP kernels */
+ boot_cpu_count++;
+#endif
+ }
+
+ /* Not the boot CPU */
+ if (found < 0)
+ return 0;
+
+ DBG("boot cpu: logical %d physical %d\n", found,
+ be32_to_cpu(intserv[found_thread]));
+ boot_cpuid = found;
+ set_hard_smp_processor_id(found, be32_to_cpu(intserv[found_thread]));
+
+ /*
+ * PAPR defines "logical" PVR values for cpus that
+ * meet various levels of the architecture:
+ * 0x0f000001 Architecture version 2.04
+ * 0x0f000002 Architecture version 2.05
+ * If the cpu-version property in the cpu node contains
+ * such a value, we call identify_cpu again with the
+ * logical PVR value in order to use the cpu feature
+ * bits appropriate for the architecture level.
+ *
+ * A POWER6 partition in "POWER6 architected" mode
+ * uses the 0x0f000002 PVR value; in POWER5+ mode
+ * it uses 0x0f000001.
+ */
+ prop = of_get_flat_dt_prop(node, "cpu-version", NULL);
+ if (prop && (be32_to_cpup(prop) & 0xff000000) == 0x0f000000)
+ identify_cpu(0, be32_to_cpup(prop));
+
+ identical_pvr_fixup(node);
+
+ check_cpu_feature_properties(node);
+ check_cpu_pa_features(node);
+ check_cpu_slb_size(node);
+
+#ifdef CONFIG_PPC64
+ if (nthreads > 1)
+ cur_cpu_spec->cpu_features |= CPU_FTR_SMT;
+ else
+ cur_cpu_spec->cpu_features &= ~CPU_FTR_SMT;
+#endif
+ return 0;
+}
+
+static int __init early_init_dt_scan_chosen_ppc(unsigned long node,
+ const char *uname,
+ int depth, void *data)
+{
+ const unsigned long *lprop; /* All these set by kernel, so no need to convert endian */
+
+ /* Use common scan routine to determine if this is the chosen node */
+ if (early_init_dt_scan_chosen(node, uname, depth, data) == 0)
+ return 0;
+
+#ifdef CONFIG_PPC64
+ /* check if iommu is forced on or off */
+ if (of_get_flat_dt_prop(node, "linux,iommu-off", NULL) != NULL)
+ iommu_is_off = 1;
+ if (of_get_flat_dt_prop(node, "linux,iommu-force-on", NULL) != NULL)
+ iommu_force_on = 1;
+#endif
+
+ /* mem=x on the command line is the preferred mechanism */
+ lprop = of_get_flat_dt_prop(node, "linux,memory-limit", NULL);
+ if (lprop)
+ memory_limit = *lprop;
+
+#ifdef CONFIG_PPC64
+ lprop = of_get_flat_dt_prop(node, "linux,tce-alloc-start", NULL);
+ if (lprop)
+ tce_alloc_start = *lprop;
+ lprop = of_get_flat_dt_prop(node, "linux,tce-alloc-end", NULL);
+ if (lprop)
+ tce_alloc_end = *lprop;
+#endif
+
+#ifdef CONFIG_KEXEC
+ lprop = of_get_flat_dt_prop(node, "linux,crashkernel-base", NULL);
+ if (lprop)
+ crashk_res.start = *lprop;
+
+ lprop = of_get_flat_dt_prop(node, "linux,crashkernel-size", NULL);
+ if (lprop)
+ crashk_res.end = crashk_res.start + *lprop - 1;
+#endif
+
+ /* break now */
+ return 1;
+}
+
+#ifdef CONFIG_PPC_PSERIES
+/*
+ * Interpret the ibm,dynamic-memory property in the
+ * /ibm,dynamic-reconfiguration-memory node.
+ * This contains a list of memory blocks along with NUMA affinity
+ * information.
+ */
+static int __init early_init_dt_scan_drconf_memory(unsigned long node)
+{
+ const __be32 *dm, *ls, *usm;
+ int l;
+ unsigned long n, flags;
+ u64 base, size, memblock_size;
+ unsigned int is_kexec_kdump = 0, rngs;
+
+ ls = of_get_flat_dt_prop(node, "ibm,lmb-size", &l);
+ if (ls == NULL || l < dt_root_size_cells * sizeof(__be32))
+ return 0;
+ memblock_size = dt_mem_next_cell(dt_root_size_cells, &ls);
+
+ dm = of_get_flat_dt_prop(node, "ibm,dynamic-memory", &l);
+ if (dm == NULL || l < sizeof(__be32))
+ return 0;
+
+ n = of_read_number(dm++, 1); /* number of entries */
+ if (l < (n * (dt_root_addr_cells + 4) + 1) * sizeof(__be32))
+ return 0;
+
+ /* check if this is a kexec/kdump kernel. */
+ usm = of_get_flat_dt_prop(node, "linux,drconf-usable-memory",
+ &l);
+ if (usm != NULL)
+ is_kexec_kdump = 1;
+
+ for (; n != 0; --n) {
+ base = dt_mem_next_cell(dt_root_addr_cells, &dm);
+ flags = of_read_number(&dm[3], 1);
+ /* skip DRC index, pad, assoc. list index, flags */
+ dm += 4;
+ /* skip this block if the reserved bit is set in flags (0x80)
+ or if the block is not assigned to this partition (0x8) */
+ if ((flags & 0x80) || !(flags & 0x8))
+ continue;
+ size = memblock_size;
+ rngs = 1;
+ if (is_kexec_kdump) {
+ /*
+ * For each memblock in ibm,dynamic-memory, a corresponding
+ * entry in linux,drconf-usable-memory property contains
+ * a counter 'p' followed by 'p' (base, size) duple.
+ * Now read the counter from
+ * linux,drconf-usable-memory property
+ */
+ rngs = dt_mem_next_cell(dt_root_size_cells, &usm);
+ if (!rngs) /* there are no (base, size) duple */
+ continue;
+ }
+ do {
+ if (is_kexec_kdump) {
+ base = dt_mem_next_cell(dt_root_addr_cells,
+ &usm);
+ size = dt_mem_next_cell(dt_root_size_cells,
+ &usm);
+ }
+ if (iommu_is_off) {
+ if (base >= 0x80000000ul)
+ continue;
+ if ((base + size) > 0x80000000ul)
+ size = 0x80000000ul - base;
+ }
+ memblock_add(base, size);
+ } while (--rngs);
+ }
+ memblock_dump_all();
+ return 0;
+}
+#else
+#define early_init_dt_scan_drconf_memory(node) 0
+#endif /* CONFIG_PPC_PSERIES */
+
+static int __init early_init_dt_scan_memory_ppc(unsigned long node,
+ const char *uname,
+ int depth, void *data)
+{
+ if (depth == 1 &&
+ strcmp(uname, "ibm,dynamic-reconfiguration-memory") == 0)
+ return early_init_dt_scan_drconf_memory(node);
+
+ return early_init_dt_scan_memory(node, uname, depth, data);
+}
+
+/*
+ * For a relocatable kernel, we need to get the memstart_addr first,
+ * then use it to calculate the virtual kernel start address. This has
+ * to happen at a very early stage (before machine_init). In this case,
+ * we just want to get the memstart_address and would not like to mess the
+ * memblock at this stage. So introduce a variable to skip the memblock_add()
+ * for this reason.
+ */
+#ifdef CONFIG_RELOCATABLE
+static int add_mem_to_memblock = 1;
+#else
+#define add_mem_to_memblock 1
+#endif
+
+void __init early_init_dt_add_memory_arch(u64 base, u64 size)
+{
+#ifdef CONFIG_PPC64
+ if (iommu_is_off) {
+ if (base >= 0x80000000ul)
+ return;
+ if ((base + size) > 0x80000000ul)
+ size = 0x80000000ul - base;
+ }
+#endif
+ /* Keep track of the beginning of memory -and- the size of
+ * the very first block in the device-tree as it represents
+ * the RMA on ppc64 server
+ */
+ if (base < memstart_addr) {
+ memstart_addr = base;
+ first_memblock_size = size;
+ }
+
+ /* Add the chunk to the MEMBLOCK list */
+ if (add_mem_to_memblock)
+ memblock_add(base, size);
+}
+
+static void __init early_reserve_mem_dt(void)
+{
+ unsigned long i, dt_root;
+ int len;
+ const __be32 *prop;
+
+ early_init_fdt_scan_reserved_mem();
+
+ dt_root = of_get_flat_dt_root();
+
+ prop = of_get_flat_dt_prop(dt_root, "reserved-ranges", &len);
+
+ if (!prop)
+ return;
+
+ DBG("Found new-style reserved-ranges\n");
+
+ /* Each reserved range is an (address,size) pair, 2 cells each,
+ * totalling 4 cells per range. */
+ for (i = 0; i < len / (sizeof(*prop) * 4); i++) {
+ u64 base, size;
+
+ base = of_read_number(prop + (i * 4) + 0, 2);
+ size = of_read_number(prop + (i * 4) + 2, 2);
+
+ if (size) {
+ DBG("reserving: %llx -> %llx\n", base, size);
+ memblock_reserve(base, size);
+ }
+ }
+}
+
+static void __init early_reserve_mem(void)
+{
+ __be64 *reserve_map;
+
+ reserve_map = (__be64 *)(((unsigned long)initial_boot_params) +
+ fdt_off_mem_rsvmap(initial_boot_params));
+
+ /* Look for the new "reserved-regions" property in the DT */
+ early_reserve_mem_dt();
+
+#ifdef CONFIG_BLK_DEV_INITRD
+ /* Then reserve the initrd, if any */
+ if (initrd_start && (initrd_end > initrd_start)) {
+ memblock_reserve(_ALIGN_DOWN(__pa(initrd_start), PAGE_SIZE),
+ _ALIGN_UP(initrd_end, PAGE_SIZE) -
+ _ALIGN_DOWN(initrd_start, PAGE_SIZE));
+ }
+#endif /* CONFIG_BLK_DEV_INITRD */
+
+#ifdef CONFIG_PPC32
+ /*
+ * Handle the case where we might be booting from an old kexec
+ * image that setup the mem_rsvmap as pairs of 32-bit values
+ */
+ if (be64_to_cpup(reserve_map) > 0xffffffffull) {
+ u32 base_32, size_32;
+ __be32 *reserve_map_32 = (__be32 *)reserve_map;
+
+ DBG("Found old 32-bit reserve map\n");
+
+ while (1) {
+ base_32 = be32_to_cpup(reserve_map_32++);
+ size_32 = be32_to_cpup(reserve_map_32++);
+ if (size_32 == 0)
+ break;
+ DBG("reserving: %x -> %x\n", base_32, size_32);
+ memblock_reserve(base_32, size_32);
+ }
+ return;
+ }
+#endif
+}
+
+void __init early_init_devtree(void *params)
+{
+ phys_addr_t limit;
+
+ DBG(" -> early_init_devtree(%p)\n", params);
+
+ /* Too early to BUG_ON(), do it by hand */
+ if (!early_init_dt_verify(params))
+ panic("BUG: Failed verifying flat device tree, bad version?");
+
+#ifdef CONFIG_PPC_RTAS
+ /* Some machines might need RTAS info for debugging, grab it now. */
+ of_scan_flat_dt(early_init_dt_scan_rtas, NULL);
+#endif
+
+#ifdef CONFIG_PPC_POWERNV
+ /* Some machines might need OPAL info for debugging, grab it now. */
+ of_scan_flat_dt(early_init_dt_scan_opal, NULL);
+#endif
+
+#ifdef CONFIG_FA_DUMP
+ /* scan tree to see if dump is active during last boot */
+ of_scan_flat_dt(early_init_dt_scan_fw_dump, NULL);
+#endif
+
+ /* Retrieve various informations from the /chosen node of the
+ * device-tree, including the platform type, initrd location and
+ * size, TCE reserve, and more ...
+ */
+ of_scan_flat_dt(early_init_dt_scan_chosen_ppc, boot_command_line);
+
+ /* Scan memory nodes and rebuild MEMBLOCKs */
+ of_scan_flat_dt(early_init_dt_scan_root, NULL);
+ of_scan_flat_dt(early_init_dt_scan_memory_ppc, NULL);
+
+ parse_early_param();
+
+ /* make sure we've parsed cmdline for mem= before this */
+ if (memory_limit)
+ first_memblock_size = min_t(u64, first_memblock_size, memory_limit);
+ setup_initial_memory_limit(memstart_addr, first_memblock_size);
+ /* Reserve MEMBLOCK regions used by kernel, initrd, dt, etc... */
+ memblock_reserve(PHYSICAL_START, __pa(klimit) - PHYSICAL_START);
+ /* If relocatable, reserve first 32k for interrupt vectors etc. */
+ if (PHYSICAL_START > MEMORY_START)
+ memblock_reserve(MEMORY_START, 0x8000);
+ reserve_kdump_trampoline();
+#ifdef CONFIG_FA_DUMP
+ /*
+ * If we fail to reserve memory for firmware-assisted dump then
+ * fallback to kexec based kdump.
+ */
+ if (fadump_reserve_mem() == 0)
+#endif
+ reserve_crashkernel();
+ early_reserve_mem();
+
+ /* Ensure that total memory size is page-aligned. */
+ limit = ALIGN(memory_limit ?: memblock_phys_mem_size(), PAGE_SIZE);
+ memblock_enforce_memory_limit(limit);
+
+ memblock_allow_resize();
+ memblock_dump_all();
+
+ DBG("Phys. mem: %llx\n", memblock_phys_mem_size());
+
+ /* We may need to relocate the flat tree, do it now.
+ * FIXME .. and the initrd too? */
+ move_device_tree();
+
+ allocate_pacas();
+
+ DBG("Scanning CPUs ...\n");
+
+ /* Retrieve CPU related informations from the flat tree
+ * (altivec support, boot CPU ID, ...)
+ */
+ of_scan_flat_dt(early_init_dt_scan_cpus, NULL);
+ if (boot_cpuid < 0) {
+ printk("Failed to identify boot CPU !\n");
+ BUG();
+ }
+
+#if defined(CONFIG_SMP) && defined(CONFIG_PPC64)
+ /* We'll later wait for secondaries to check in; there are
+ * NCPUS-1 non-boot CPUs :-)
+ */
+ spinning_secondaries = boot_cpu_count - 1;
+#endif
+
+#ifdef CONFIG_PPC_POWERNV
+ /* Scan and build the list of machine check recoverable ranges */
+ of_scan_flat_dt(early_init_dt_scan_recoverable_ranges, NULL);
+#endif
+
+ DBG(" <- early_init_devtree()\n");
+}
+
+#ifdef CONFIG_RELOCATABLE
+/*
+ * This function run before early_init_devtree, so we have to init
+ * initial_boot_params.
+ */
+void __init early_get_first_memblock_info(void *params, phys_addr_t *size)
+{
+ /* Setup flat device-tree pointer */
+ initial_boot_params = params;
+
+ /*
+ * Scan the memory nodes and set add_mem_to_memblock to 0 to avoid
+ * mess the memblock.
+ */
+ add_mem_to_memblock = 0;
+ of_scan_flat_dt(early_init_dt_scan_root, NULL);
+ of_scan_flat_dt(early_init_dt_scan_memory_ppc, NULL);
+ add_mem_to_memblock = 1;
+
+ if (size)
+ *size = first_memblock_size;
+}
+#endif
+
+/*******
+ *
+ * New implementation of the OF "find" APIs, return a refcounted
+ * object, call of_node_put() when done. The device tree and list
+ * are protected by a rw_lock.
+ *
+ * Note that property management will need some locking as well,
+ * this isn't dealt with yet.
+ *
+ *******/
+
+/**
+ * of_get_ibm_chip_id - Returns the IBM "chip-id" of a device
+ * @np: device node of the device
+ *
+ * This looks for a property "ibm,chip-id" in the node or any
+ * of its parents and returns its content, or -1 if it cannot
+ * be found.
+ */
+int of_get_ibm_chip_id(struct device_node *np)
+{
+ of_node_get(np);
+ while(np) {
+ struct device_node *old = np;
+ const __be32 *prop;
+
+ prop = of_get_property(np, "ibm,chip-id", NULL);
+ if (prop) {
+ of_node_put(np);
+ return be32_to_cpup(prop);
+ }
+ np = of_get_parent(np);
+ of_node_put(old);
+ }
+ return -1;
+}
+
+/**
+ * cpu_to_chip_id - Return the cpus chip-id
+ * @cpu: The logical cpu number.
+ *
+ * Return the value of the ibm,chip-id property corresponding to the given
+ * logical cpu number. If the chip-id can not be found, returns -1.
+ */
+int cpu_to_chip_id(int cpu)
+{
+ struct device_node *np;
+
+ np = of_get_cpu_node(cpu, NULL);
+ if (!np)
+ return -1;
+
+ of_node_put(np);
+ return of_get_ibm_chip_id(np);
+}
+EXPORT_SYMBOL(cpu_to_chip_id);
+
+bool arch_match_cpu_phys_id(int cpu, u64 phys_id)
+{
+ return (int)phys_id == get_hard_smp_processor_id(cpu);
+}