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-rw-r--r--arch/powerpc/kernel/setup-common.c1013
1 files changed, 1013 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/setup-common.c b/arch/powerpc/kernel/setup-common.c
new file mode 100644
index 000000000..20f72cd1d
--- /dev/null
+++ b/arch/powerpc/kernel/setup-common.c
@@ -0,0 +1,1013 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Common boot and setup code for both 32-bit and 64-bit.
+ * Extracted from arch/powerpc/kernel/setup_64.c.
+ *
+ * Copyright (C) 2001 PPC64 Team, IBM Corp
+ */
+
+#undef DEBUG
+
+#include <linux/export.h>
+#include <linux/panic_notifier.h>
+#include <linux/string.h>
+#include <linux/sched.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/reboot.h>
+#include <linux/delay.h>
+#include <linux/initrd.h>
+#include <linux/platform_device.h>
+#include <linux/printk.h>
+#include <linux/seq_file.h>
+#include <linux/ioport.h>
+#include <linux/console.h>
+#include <linux/screen_info.h>
+#include <linux/root_dev.h>
+#include <linux/cpu.h>
+#include <linux/unistd.h>
+#include <linux/seq_buf.h>
+#include <linux/serial.h>
+#include <linux/serial_8250.h>
+#include <linux/percpu.h>
+#include <linux/memblock.h>
+#include <linux/of.h>
+#include <linux/of_fdt.h>
+#include <linux/of_irq.h>
+#include <linux/hugetlb.h>
+#include <linux/pgtable.h>
+#include <asm/io.h>
+#include <asm/paca.h>
+#include <asm/processor.h>
+#include <asm/vdso_datapage.h>
+#include <asm/smp.h>
+#include <asm/elf.h>
+#include <asm/machdep.h>
+#include <asm/time.h>
+#include <asm/cputable.h>
+#include <asm/sections.h>
+#include <asm/firmware.h>
+#include <asm/btext.h>
+#include <asm/nvram.h>
+#include <asm/setup.h>
+#include <asm/rtas.h>
+#include <asm/iommu.h>
+#include <asm/serial.h>
+#include <asm/cache.h>
+#include <asm/page.h>
+#include <asm/mmu.h>
+#include <asm/xmon.h>
+#include <asm/cputhreads.h>
+#include <mm/mmu_decl.h>
+#include <asm/archrandom.h>
+#include <asm/fadump.h>
+#include <asm/udbg.h>
+#include <asm/hugetlb.h>
+#include <asm/livepatch.h>
+#include <asm/mmu_context.h>
+#include <asm/cpu_has_feature.h>
+#include <asm/kasan.h>
+#include <asm/mce.h>
+
+#include "setup.h"
+
+#ifdef DEBUG
+#define DBG(fmt...) udbg_printf(fmt)
+#else
+#define DBG(fmt...)
+#endif
+
+/* The main machine-dep calls structure
+ */
+struct machdep_calls ppc_md;
+EXPORT_SYMBOL(ppc_md);
+struct machdep_calls *machine_id;
+EXPORT_SYMBOL(machine_id);
+
+int boot_cpuid = -1;
+EXPORT_SYMBOL_GPL(boot_cpuid);
+
+#ifdef CONFIG_PPC64
+int boot_cpu_hwid = -1;
+#endif
+
+/*
+ * These are used in binfmt_elf.c to put aux entries on the stack
+ * for each elf executable being started.
+ */
+int dcache_bsize;
+int icache_bsize;
+
+/*
+ * This still seems to be needed... -- paulus
+ */
+struct screen_info screen_info = {
+ .orig_x = 0,
+ .orig_y = 25,
+ .orig_video_cols = 80,
+ .orig_video_lines = 25,
+ .orig_video_isVGA = 1,
+ .orig_video_points = 16
+};
+#if defined(CONFIG_FB_VGA16_MODULE)
+EXPORT_SYMBOL(screen_info);
+#endif
+
+/* Variables required to store legacy IO irq routing */
+int of_i8042_kbd_irq;
+EXPORT_SYMBOL_GPL(of_i8042_kbd_irq);
+int of_i8042_aux_irq;
+EXPORT_SYMBOL_GPL(of_i8042_aux_irq);
+
+#ifdef __DO_IRQ_CANON
+/* XXX should go elsewhere eventually */
+int ppc_do_canonicalize_irqs;
+EXPORT_SYMBOL(ppc_do_canonicalize_irqs);
+#endif
+
+#ifdef CONFIG_CRASH_CORE
+/* This keeps a track of which one is the crashing cpu. */
+int crashing_cpu = -1;
+#endif
+
+/* also used by kexec */
+void machine_shutdown(void)
+{
+ /*
+ * if fadump is active, cleanup the fadump registration before we
+ * shutdown.
+ */
+ fadump_cleanup();
+
+ if (ppc_md.machine_shutdown)
+ ppc_md.machine_shutdown();
+}
+
+static void machine_hang(void)
+{
+ pr_emerg("System Halted, OK to turn off power\n");
+ local_irq_disable();
+ while (1)
+ ;
+}
+
+void machine_restart(char *cmd)
+{
+ machine_shutdown();
+ if (ppc_md.restart)
+ ppc_md.restart(cmd);
+
+ smp_send_stop();
+
+ do_kernel_restart(cmd);
+ mdelay(1000);
+
+ machine_hang();
+}
+
+void machine_power_off(void)
+{
+ machine_shutdown();
+ do_kernel_power_off();
+ smp_send_stop();
+ machine_hang();
+}
+/* Used by the G5 thermal driver */
+EXPORT_SYMBOL_GPL(machine_power_off);
+
+void (*pm_power_off)(void);
+EXPORT_SYMBOL_GPL(pm_power_off);
+
+size_t __must_check arch_get_random_seed_longs(unsigned long *v, size_t max_longs)
+{
+ if (max_longs && ppc_md.get_random_seed && ppc_md.get_random_seed(v))
+ return 1;
+ return 0;
+}
+EXPORT_SYMBOL(arch_get_random_seed_longs);
+
+void machine_halt(void)
+{
+ machine_shutdown();
+ if (ppc_md.halt)
+ ppc_md.halt();
+
+ smp_send_stop();
+ machine_hang();
+}
+
+#ifdef CONFIG_SMP
+DEFINE_PER_CPU(unsigned int, cpu_pvr);
+#endif
+
+static void show_cpuinfo_summary(struct seq_file *m)
+{
+ struct device_node *root;
+ const char *model = NULL;
+ unsigned long bogosum = 0;
+ int i;
+
+ if (IS_ENABLED(CONFIG_SMP) && IS_ENABLED(CONFIG_PPC32)) {
+ for_each_online_cpu(i)
+ bogosum += loops_per_jiffy;
+ seq_printf(m, "total bogomips\t: %lu.%02lu\n",
+ bogosum / (500000 / HZ), bogosum / (5000 / HZ) % 100);
+ }
+ seq_printf(m, "timebase\t: %lu\n", ppc_tb_freq);
+ if (ppc_md.name)
+ seq_printf(m, "platform\t: %s\n", ppc_md.name);
+ root = of_find_node_by_path("/");
+ if (root)
+ model = of_get_property(root, "model", NULL);
+ if (model)
+ seq_printf(m, "model\t\t: %s\n", model);
+ of_node_put(root);
+
+ if (ppc_md.show_cpuinfo != NULL)
+ ppc_md.show_cpuinfo(m);
+
+ /* Display the amount of memory */
+ if (IS_ENABLED(CONFIG_PPC32))
+ seq_printf(m, "Memory\t\t: %d MB\n",
+ (unsigned int)(total_memory / (1024 * 1024)));
+}
+
+static int show_cpuinfo(struct seq_file *m, void *v)
+{
+ unsigned long cpu_id = (unsigned long)v - 1;
+ unsigned int pvr;
+ unsigned long proc_freq;
+ unsigned short maj;
+ unsigned short min;
+
+#ifdef CONFIG_SMP
+ pvr = per_cpu(cpu_pvr, cpu_id);
+#else
+ pvr = mfspr(SPRN_PVR);
+#endif
+ maj = (pvr >> 8) & 0xFF;
+ min = pvr & 0xFF;
+
+ seq_printf(m, "processor\t: %lu\ncpu\t\t: ", cpu_id);
+
+ if (cur_cpu_spec->pvr_mask && cur_cpu_spec->cpu_name)
+ seq_puts(m, cur_cpu_spec->cpu_name);
+ else
+ seq_printf(m, "unknown (%08x)", pvr);
+
+ if (cpu_has_feature(CPU_FTR_ALTIVEC))
+ seq_puts(m, ", altivec supported");
+
+ seq_putc(m, '\n');
+
+#ifdef CONFIG_TAU
+ if (cpu_has_feature(CPU_FTR_TAU)) {
+ if (IS_ENABLED(CONFIG_TAU_AVERAGE)) {
+ /* more straightforward, but potentially misleading */
+ seq_printf(m, "temperature \t: %u C (uncalibrated)\n",
+ cpu_temp(cpu_id));
+ } else {
+ /* show the actual temp sensor range */
+ u32 temp;
+ temp = cpu_temp_both(cpu_id);
+ seq_printf(m, "temperature \t: %u-%u C (uncalibrated)\n",
+ temp & 0xff, temp >> 16);
+ }
+ }
+#endif /* CONFIG_TAU */
+
+ /*
+ * Platforms that have variable clock rates, should implement
+ * the method ppc_md.get_proc_freq() that reports the clock
+ * rate of a given cpu. The rest can use ppc_proc_freq to
+ * report the clock rate that is same across all cpus.
+ */
+ if (ppc_md.get_proc_freq)
+ proc_freq = ppc_md.get_proc_freq(cpu_id);
+ else
+ proc_freq = ppc_proc_freq;
+
+ if (proc_freq)
+ seq_printf(m, "clock\t\t: %lu.%06luMHz\n",
+ proc_freq / 1000000, proc_freq % 1000000);
+
+ /* If we are a Freescale core do a simple check so
+ * we don't have to keep adding cases in the future */
+ if (PVR_VER(pvr) & 0x8000) {
+ switch (PVR_VER(pvr)) {
+ case 0x8000: /* 7441/7450/7451, Voyager */
+ case 0x8001: /* 7445/7455, Apollo 6 */
+ case 0x8002: /* 7447/7457, Apollo 7 */
+ case 0x8003: /* 7447A, Apollo 7 PM */
+ case 0x8004: /* 7448, Apollo 8 */
+ case 0x800c: /* 7410, Nitro */
+ maj = ((pvr >> 8) & 0xF);
+ min = PVR_MIN(pvr);
+ break;
+ default: /* e500/book-e */
+ maj = PVR_MAJ(pvr);
+ min = PVR_MIN(pvr);
+ break;
+ }
+ } else {
+ switch (PVR_VER(pvr)) {
+ case 0x1008: /* 740P/750P ?? */
+ maj = ((pvr >> 8) & 0xFF) - 1;
+ min = pvr & 0xFF;
+ break;
+ case 0x004e: /* POWER9 bits 12-15 give chip type */
+ case 0x0080: /* POWER10 bit 12 gives SMT8/4 */
+ maj = (pvr >> 8) & 0x0F;
+ min = pvr & 0xFF;
+ break;
+ default:
+ maj = (pvr >> 8) & 0xFF;
+ min = pvr & 0xFF;
+ break;
+ }
+ }
+
+ seq_printf(m, "revision\t: %hd.%hd (pvr %04x %04x)\n",
+ maj, min, PVR_VER(pvr), PVR_REV(pvr));
+
+ if (IS_ENABLED(CONFIG_PPC32))
+ seq_printf(m, "bogomips\t: %lu.%02lu\n", loops_per_jiffy / (500000 / HZ),
+ (loops_per_jiffy / (5000 / HZ)) % 100);
+
+ seq_putc(m, '\n');
+
+ /* If this is the last cpu, print the summary */
+ if (cpumask_next(cpu_id, cpu_online_mask) >= nr_cpu_ids)
+ show_cpuinfo_summary(m);
+
+ return 0;
+}
+
+static void *c_start(struct seq_file *m, loff_t *pos)
+{
+ if (*pos == 0) /* just in case, cpu 0 is not the first */
+ *pos = cpumask_first(cpu_online_mask);
+ else
+ *pos = cpumask_next(*pos - 1, cpu_online_mask);
+ if ((*pos) < nr_cpu_ids)
+ return (void *)(unsigned long)(*pos + 1);
+ return NULL;
+}
+
+static void *c_next(struct seq_file *m, void *v, loff_t *pos)
+{
+ (*pos)++;
+ return c_start(m, pos);
+}
+
+static void c_stop(struct seq_file *m, void *v)
+{
+}
+
+const struct seq_operations cpuinfo_op = {
+ .start = c_start,
+ .next = c_next,
+ .stop = c_stop,
+ .show = show_cpuinfo,
+};
+
+void __init check_for_initrd(void)
+{
+#ifdef CONFIG_BLK_DEV_INITRD
+ DBG(" -> check_for_initrd() initrd_start=0x%lx initrd_end=0x%lx\n",
+ initrd_start, initrd_end);
+
+ /* If we were passed an initrd, set the ROOT_DEV properly if the values
+ * look sensible. If not, clear initrd reference.
+ */
+ if (is_kernel_addr(initrd_start) && is_kernel_addr(initrd_end) &&
+ initrd_end > initrd_start)
+ ROOT_DEV = Root_RAM0;
+ else
+ initrd_start = initrd_end = 0;
+
+ if (initrd_start)
+ pr_info("Found initrd at 0x%lx:0x%lx\n", initrd_start, initrd_end);
+
+ DBG(" <- check_for_initrd()\n");
+#endif /* CONFIG_BLK_DEV_INITRD */
+}
+
+#ifdef CONFIG_SMP
+
+int threads_per_core, threads_per_subcore, threads_shift __read_mostly;
+cpumask_t threads_core_mask __read_mostly;
+EXPORT_SYMBOL_GPL(threads_per_core);
+EXPORT_SYMBOL_GPL(threads_per_subcore);
+EXPORT_SYMBOL_GPL(threads_shift);
+EXPORT_SYMBOL_GPL(threads_core_mask);
+
+static void __init cpu_init_thread_core_maps(int tpc)
+{
+ int i;
+
+ threads_per_core = tpc;
+ threads_per_subcore = tpc;
+ cpumask_clear(&threads_core_mask);
+
+ /* This implementation only supports power of 2 number of threads
+ * for simplicity and performance
+ */
+ threads_shift = ilog2(tpc);
+ BUG_ON(tpc != (1 << threads_shift));
+
+ for (i = 0; i < tpc; i++)
+ cpumask_set_cpu(i, &threads_core_mask);
+
+ printk(KERN_INFO "CPU maps initialized for %d thread%s per core\n",
+ tpc, tpc > 1 ? "s" : "");
+ printk(KERN_DEBUG " (thread shift is %d)\n", threads_shift);
+}
+
+
+u32 *cpu_to_phys_id = NULL;
+
+/**
+ * setup_cpu_maps - initialize the following cpu maps:
+ * cpu_possible_mask
+ * cpu_present_mask
+ *
+ * Having the possible map set up early allows us to restrict allocations
+ * of things like irqstacks to nr_cpu_ids rather than NR_CPUS.
+ *
+ * We do not initialize the online map here; cpus set their own bits in
+ * cpu_online_mask as they come up.
+ *
+ * This function is valid only for Open Firmware systems. finish_device_tree
+ * must be called before using this.
+ *
+ * While we're here, we may as well set the "physical" cpu ids in the paca.
+ *
+ * NOTE: This must match the parsing done in early_init_dt_scan_cpus.
+ */
+void __init smp_setup_cpu_maps(void)
+{
+ struct device_node *dn;
+ int cpu = 0;
+ int nthreads = 1;
+
+ DBG("smp_setup_cpu_maps()\n");
+
+ cpu_to_phys_id = memblock_alloc(nr_cpu_ids * sizeof(u32),
+ __alignof__(u32));
+ if (!cpu_to_phys_id)
+ panic("%s: Failed to allocate %zu bytes align=0x%zx\n",
+ __func__, nr_cpu_ids * sizeof(u32), __alignof__(u32));
+
+ for_each_node_by_type(dn, "cpu") {
+ const __be32 *intserv;
+ __be32 cpu_be;
+ int j, len;
+
+ DBG(" * %pOF...\n", dn);
+
+ intserv = of_get_property(dn, "ibm,ppc-interrupt-server#s",
+ &len);
+ if (intserv) {
+ DBG(" ibm,ppc-interrupt-server#s -> %lu threads\n",
+ (len / sizeof(int)));
+ } else {
+ DBG(" no ibm,ppc-interrupt-server#s -> 1 thread\n");
+ intserv = of_get_property(dn, "reg", &len);
+ if (!intserv) {
+ cpu_be = cpu_to_be32(cpu);
+ /* XXX: what is this? uninitialized?? */
+ intserv = &cpu_be; /* assume logical == phys */
+ len = 4;
+ }
+ }
+
+ nthreads = len / sizeof(int);
+
+ for (j = 0; j < nthreads && cpu < nr_cpu_ids; j++) {
+ bool avail;
+
+ DBG(" thread %d -> cpu %d (hard id %d)\n",
+ j, cpu, be32_to_cpu(intserv[j]));
+
+ avail = of_device_is_available(dn);
+ if (!avail)
+ avail = !of_property_match_string(dn,
+ "enable-method", "spin-table");
+
+ set_cpu_present(cpu, avail);
+ set_cpu_possible(cpu, true);
+ cpu_to_phys_id[cpu] = be32_to_cpu(intserv[j]);
+ cpu++;
+ }
+
+ if (cpu >= nr_cpu_ids) {
+ of_node_put(dn);
+ break;
+ }
+ }
+
+ /* If no SMT supported, nthreads is forced to 1 */
+ if (!cpu_has_feature(CPU_FTR_SMT)) {
+ DBG(" SMT disabled ! nthreads forced to 1\n");
+ nthreads = 1;
+ }
+
+#ifdef CONFIG_PPC64
+ /*
+ * On pSeries LPAR, we need to know how many cpus
+ * could possibly be added to this partition.
+ */
+ if (firmware_has_feature(FW_FEATURE_LPAR) &&
+ (dn = of_find_node_by_path("/rtas"))) {
+ int num_addr_cell, num_size_cell, maxcpus;
+ const __be32 *ireg;
+
+ num_addr_cell = of_n_addr_cells(dn);
+ num_size_cell = of_n_size_cells(dn);
+
+ ireg = of_get_property(dn, "ibm,lrdr-capacity", NULL);
+
+ if (!ireg)
+ goto out;
+
+ maxcpus = be32_to_cpup(ireg + num_addr_cell + num_size_cell);
+
+ /* Double maxcpus for processors which have SMT capability */
+ if (cpu_has_feature(CPU_FTR_SMT))
+ maxcpus *= nthreads;
+
+ if (maxcpus > nr_cpu_ids) {
+ printk(KERN_WARNING
+ "Partition configured for %d cpus, "
+ "operating system maximum is %u.\n",
+ maxcpus, nr_cpu_ids);
+ maxcpus = nr_cpu_ids;
+ } else
+ printk(KERN_INFO "Partition configured for %d cpus.\n",
+ maxcpus);
+
+ for (cpu = 0; cpu < maxcpus; cpu++)
+ set_cpu_possible(cpu, true);
+ out:
+ of_node_put(dn);
+ }
+ vdso_data->processorCount = num_present_cpus();
+#endif /* CONFIG_PPC64 */
+
+ /* Initialize CPU <=> thread mapping/
+ *
+ * WARNING: We assume that the number of threads is the same for
+ * every CPU in the system. If that is not the case, then some code
+ * here will have to be reworked
+ */
+ cpu_init_thread_core_maps(nthreads);
+
+ /* Now that possible cpus are set, set nr_cpu_ids for later use */
+ setup_nr_cpu_ids();
+
+ free_unused_pacas();
+}
+#endif /* CONFIG_SMP */
+
+#ifdef CONFIG_PCSPKR_PLATFORM
+static __init int add_pcspkr(void)
+{
+ struct device_node *np;
+ struct platform_device *pd;
+ int ret;
+
+ np = of_find_compatible_node(NULL, NULL, "pnpPNP,100");
+ of_node_put(np);
+ if (!np)
+ return -ENODEV;
+
+ pd = platform_device_alloc("pcspkr", -1);
+ if (!pd)
+ return -ENOMEM;
+
+ ret = platform_device_add(pd);
+ if (ret)
+ platform_device_put(pd);
+
+ return ret;
+}
+device_initcall(add_pcspkr);
+#endif /* CONFIG_PCSPKR_PLATFORM */
+
+static char ppc_hw_desc_buf[128] __initdata;
+
+struct seq_buf ppc_hw_desc __initdata = {
+ .buffer = ppc_hw_desc_buf,
+ .size = sizeof(ppc_hw_desc_buf),
+ .len = 0,
+ .readpos = 0,
+};
+
+static __init void probe_machine(void)
+{
+ extern struct machdep_calls __machine_desc_start;
+ extern struct machdep_calls __machine_desc_end;
+ unsigned int i;
+
+ /*
+ * Iterate all ppc_md structures until we find the proper
+ * one for the current machine type
+ */
+ DBG("Probing machine type ...\n");
+
+ /*
+ * Check ppc_md is empty, if not we have a bug, ie, we setup an
+ * entry before probe_machine() which will be overwritten
+ */
+ for (i = 0; i < (sizeof(ppc_md) / sizeof(void *)); i++) {
+ if (((void **)&ppc_md)[i]) {
+ printk(KERN_ERR "Entry %d in ppc_md non empty before"
+ " machine probe !\n", i);
+ }
+ }
+
+ for (machine_id = &__machine_desc_start;
+ machine_id < &__machine_desc_end;
+ machine_id++) {
+ DBG(" %s ...\n", machine_id->name);
+ if (machine_id->compatible && !of_machine_is_compatible(machine_id->compatible))
+ continue;
+ memcpy(&ppc_md, machine_id, sizeof(struct machdep_calls));
+ if (ppc_md.probe && !ppc_md.probe())
+ continue;
+ DBG(" %s match !\n", machine_id->name);
+ break;
+ }
+ /* What can we do if we didn't find ? */
+ if (machine_id >= &__machine_desc_end) {
+ pr_err("No suitable machine description found !\n");
+ for (;;);
+ }
+
+ // Append the machine name to other info we've gathered
+ seq_buf_puts(&ppc_hw_desc, ppc_md.name);
+
+ // Set the generic hardware description shown in oopses
+ dump_stack_set_arch_desc(ppc_hw_desc.buffer);
+
+ pr_info("Hardware name: %s\n", ppc_hw_desc.buffer);
+}
+
+/* Match a class of boards, not a specific device configuration. */
+int check_legacy_ioport(unsigned long base_port)
+{
+ struct device_node *parent, *np = NULL;
+ int ret = -ENODEV;
+
+ switch(base_port) {
+ case I8042_DATA_REG:
+ if (!(np = of_find_compatible_node(NULL, NULL, "pnpPNP,303")))
+ np = of_find_compatible_node(NULL, NULL, "pnpPNP,f03");
+ if (np) {
+ parent = of_get_parent(np);
+
+ of_i8042_kbd_irq = irq_of_parse_and_map(parent, 0);
+ if (!of_i8042_kbd_irq)
+ of_i8042_kbd_irq = 1;
+
+ of_i8042_aux_irq = irq_of_parse_and_map(parent, 1);
+ if (!of_i8042_aux_irq)
+ of_i8042_aux_irq = 12;
+
+ of_node_put(np);
+ np = parent;
+ break;
+ }
+ np = of_find_node_by_type(NULL, "8042");
+ /* Pegasos has no device_type on its 8042 node, look for the
+ * name instead */
+ if (!np)
+ np = of_find_node_by_name(NULL, "8042");
+ if (np) {
+ of_i8042_kbd_irq = 1;
+ of_i8042_aux_irq = 12;
+ }
+ break;
+ case FDC_BASE: /* FDC1 */
+ np = of_find_node_by_type(NULL, "fdc");
+ break;
+ default:
+ /* ipmi is supposed to fail here */
+ break;
+ }
+ if (!np)
+ return ret;
+ parent = of_get_parent(np);
+ if (parent) {
+ if (of_node_is_type(parent, "isa"))
+ ret = 0;
+ of_node_put(parent);
+ }
+ of_node_put(np);
+ return ret;
+}
+EXPORT_SYMBOL(check_legacy_ioport);
+
+/*
+ * Panic notifiers setup
+ *
+ * We have 3 notifiers for powerpc, each one from a different "nature":
+ *
+ * - ppc_panic_fadump_handler() is a hypervisor notifier, which hard-disables
+ * IRQs and deal with the Firmware-Assisted dump, when it is configured;
+ * should run early in the panic path.
+ *
+ * - dump_kernel_offset() is an informative notifier, just showing the KASLR
+ * offset if we have RANDOMIZE_BASE set.
+ *
+ * - ppc_panic_platform_handler() is a low-level handler that's registered
+ * only if the platform wishes to perform final actions in the panic path,
+ * hence it should run late and might not even return. Currently, only
+ * pseries and ps3 platforms register callbacks.
+ */
+static int ppc_panic_fadump_handler(struct notifier_block *this,
+ unsigned long event, void *ptr)
+{
+ /*
+ * panic does a local_irq_disable, but we really
+ * want interrupts to be hard disabled.
+ */
+ hard_irq_disable();
+
+ /*
+ * If firmware-assisted dump has been registered then trigger
+ * its callback and let the firmware handles everything else.
+ */
+ crash_fadump(NULL, ptr);
+
+ return NOTIFY_DONE;
+}
+
+static int dump_kernel_offset(struct notifier_block *self, unsigned long v,
+ void *p)
+{
+ pr_emerg("Kernel Offset: 0x%lx from 0x%lx\n",
+ kaslr_offset(), KERNELBASE);
+
+ return NOTIFY_DONE;
+}
+
+static int ppc_panic_platform_handler(struct notifier_block *this,
+ unsigned long event, void *ptr)
+{
+ /*
+ * This handler is only registered if we have a panic callback
+ * on ppc_md, hence NULL check is not needed.
+ * Also, it may not return, so it runs really late on panic path.
+ */
+ ppc_md.panic(ptr);
+
+ return NOTIFY_DONE;
+}
+
+static struct notifier_block ppc_fadump_block = {
+ .notifier_call = ppc_panic_fadump_handler,
+ .priority = INT_MAX, /* run early, to notify the firmware ASAP */
+};
+
+static struct notifier_block kernel_offset_notifier = {
+ .notifier_call = dump_kernel_offset,
+};
+
+static struct notifier_block ppc_panic_block = {
+ .notifier_call = ppc_panic_platform_handler,
+ .priority = INT_MIN, /* may not return; must be done last */
+};
+
+void __init setup_panic(void)
+{
+ /* Hard-disables IRQs + deal with FW-assisted dump (fadump) */
+ atomic_notifier_chain_register(&panic_notifier_list,
+ &ppc_fadump_block);
+
+ if (IS_ENABLED(CONFIG_RANDOMIZE_BASE) && kaslr_offset() > 0)
+ atomic_notifier_chain_register(&panic_notifier_list,
+ &kernel_offset_notifier);
+
+ /* Low-level platform-specific routines that should run on panic */
+ if (ppc_md.panic)
+ atomic_notifier_chain_register(&panic_notifier_list,
+ &ppc_panic_block);
+}
+
+#ifdef CONFIG_CHECK_CACHE_COHERENCY
+/*
+ * For platforms that have configurable cache-coherency. This function
+ * checks that the cache coherency setting of the kernel matches the setting
+ * left by the firmware, as indicated in the device tree. Since a mismatch
+ * will eventually result in DMA failures, we print * and error and call
+ * BUG() in that case.
+ */
+
+#define KERNEL_COHERENCY (!IS_ENABLED(CONFIG_NOT_COHERENT_CACHE))
+
+static int __init check_cache_coherency(void)
+{
+ struct device_node *np;
+ const void *prop;
+ bool devtree_coherency;
+
+ np = of_find_node_by_path("/");
+ prop = of_get_property(np, "coherency-off", NULL);
+ of_node_put(np);
+
+ devtree_coherency = prop ? false : true;
+
+ if (devtree_coherency != KERNEL_COHERENCY) {
+ printk(KERN_ERR
+ "kernel coherency:%s != device tree_coherency:%s\n",
+ KERNEL_COHERENCY ? "on" : "off",
+ devtree_coherency ? "on" : "off");
+ BUG();
+ }
+
+ return 0;
+}
+
+late_initcall(check_cache_coherency);
+#endif /* CONFIG_CHECK_CACHE_COHERENCY */
+
+void ppc_printk_progress(char *s, unsigned short hex)
+{
+ pr_info("%s\n", s);
+}
+
+static __init void print_system_info(void)
+{
+ pr_info("-----------------------------------------------------\n");
+ pr_info("phys_mem_size = 0x%llx\n",
+ (unsigned long long)memblock_phys_mem_size());
+
+ pr_info("dcache_bsize = 0x%x\n", dcache_bsize);
+ pr_info("icache_bsize = 0x%x\n", icache_bsize);
+
+ pr_info("cpu_features = 0x%016lx\n", cur_cpu_spec->cpu_features);
+ pr_info(" possible = 0x%016lx\n",
+ (unsigned long)CPU_FTRS_POSSIBLE);
+ pr_info(" always = 0x%016lx\n",
+ (unsigned long)CPU_FTRS_ALWAYS);
+ pr_info("cpu_user_features = 0x%08x 0x%08x\n",
+ cur_cpu_spec->cpu_user_features,
+ cur_cpu_spec->cpu_user_features2);
+ pr_info("mmu_features = 0x%08x\n", cur_cpu_spec->mmu_features);
+#ifdef CONFIG_PPC64
+ pr_info("firmware_features = 0x%016lx\n", powerpc_firmware_features);
+#ifdef CONFIG_PPC_BOOK3S
+ pr_info("vmalloc start = 0x%lx\n", KERN_VIRT_START);
+ pr_info("IO start = 0x%lx\n", KERN_IO_START);
+ pr_info("vmemmap start = 0x%lx\n", (unsigned long)vmemmap);
+#endif
+#endif
+
+ if (!early_radix_enabled())
+ print_system_hash_info();
+
+ if (PHYSICAL_START > 0)
+ pr_info("physical_start = 0x%llx\n",
+ (unsigned long long)PHYSICAL_START);
+ pr_info("-----------------------------------------------------\n");
+}
+
+#ifdef CONFIG_SMP
+static void __init smp_setup_pacas(void)
+{
+ int cpu;
+
+ for_each_possible_cpu(cpu) {
+ if (cpu == smp_processor_id())
+ continue;
+ allocate_paca(cpu);
+ set_hard_smp_processor_id(cpu, cpu_to_phys_id[cpu]);
+ }
+
+ memblock_free(cpu_to_phys_id, nr_cpu_ids * sizeof(u32));
+ cpu_to_phys_id = NULL;
+}
+#endif
+
+/*
+ * Called into from start_kernel this initializes memblock, which is used
+ * to manage page allocation until mem_init is called.
+ */
+void __init setup_arch(char **cmdline_p)
+{
+ kasan_init();
+
+ *cmdline_p = boot_command_line;
+
+ /* Set a half-reasonable default so udelay does something sensible */
+ loops_per_jiffy = 500000000 / HZ;
+
+ /* Unflatten the device-tree passed by prom_init or kexec */
+ unflatten_device_tree();
+
+ /*
+ * Initialize cache line/block info from device-tree (on ppc64) or
+ * just cputable (on ppc32).
+ */
+ initialize_cache_info();
+
+ /* Initialize RTAS if available. */
+ rtas_initialize();
+
+ /* Check if we have an initrd provided via the device-tree. */
+ check_for_initrd();
+
+ /* Probe the machine type, establish ppc_md. */
+ probe_machine();
+
+ /* Setup panic notifier if requested by the platform. */
+ setup_panic();
+
+ /*
+ * Configure ppc_md.power_save (ppc32 only, 64-bit machines do
+ * it from their respective probe() function.
+ */
+ setup_power_save();
+
+ /* Discover standard serial ports. */
+ find_legacy_serial_ports();
+
+ /* Register early console with the printk subsystem. */
+ register_early_udbg_console();
+
+ /* Setup the various CPU maps based on the device-tree. */
+ smp_setup_cpu_maps();
+
+ /* Initialize xmon. */
+ xmon_setup();
+
+ /* Check the SMT related command line arguments (ppc64). */
+ check_smt_enabled();
+
+ /* Parse memory topology */
+ mem_topology_setup();
+ /* Set max_mapnr before paging_init() */
+ set_max_mapnr(max_pfn);
+
+ /*
+ * Release secondary cpus out of their spinloops at 0x60 now that
+ * we can map physical -> logical CPU ids.
+ *
+ * Freescale Book3e parts spin in a loop provided by firmware,
+ * so smp_release_cpus() does nothing for them.
+ */
+#ifdef CONFIG_SMP
+ smp_setup_pacas();
+
+ /* On BookE, setup per-core TLB data structures. */
+ setup_tlb_core_data();
+#endif
+
+ /* Print various info about the machine that has been gathered so far. */
+ print_system_info();
+
+ klp_init_thread_info(&init_task);
+
+ setup_initial_init_mm(_stext, _etext, _edata, _end);
+ /* sched_init() does the mmgrab(&init_mm) for the primary CPU */
+ VM_WARN_ON(cpumask_test_cpu(smp_processor_id(), mm_cpumask(&init_mm)));
+ cpumask_set_cpu(smp_processor_id(), mm_cpumask(&init_mm));
+ inc_mm_active_cpus(&init_mm);
+ mm_iommu_init(&init_mm);
+
+ irqstack_early_init();
+ exc_lvl_early_init();
+ emergency_stack_init();
+
+ mce_init();
+ smp_release_cpus();
+
+ initmem_init();
+
+ /*
+ * Reserve large chunks of memory for use by CMA for KVM and hugetlb. These must
+ * be called after initmem_init(), so that pageblock_order is initialised.
+ */
+ kvm_cma_reserve();
+ gigantic_hugetlb_cma_reserve();
+
+ early_memtest(min_low_pfn << PAGE_SHIFT, max_low_pfn << PAGE_SHIFT);
+
+ if (ppc_md.setup_arch)
+ ppc_md.setup_arch();
+
+ setup_barrier_nospec();
+ setup_spectre_v2();
+
+ paging_init();
+
+ /* Initialize the MMU context management stuff. */
+ mmu_context_init();
+
+ /* Interrupt code needs to be 64K-aligned. */
+ if (IS_ENABLED(CONFIG_PPC64) && (unsigned long)_stext & 0xffff)
+ panic("Kernelbase not 64K-aligned (0x%lx)!\n",
+ (unsigned long)_stext);
+}