v4.19.13 snapshot.
diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c
new file mode 100644
index 0000000..faf0022
--- /dev/null
+++ b/arch/powerpc/kernel/setup_64.c
@@ -0,0 +1,996 @@
+/*
+ *
+ * Common boot and setup code.
+ *
+ * Copyright (C) 2001 PPC64 Team, IBM Corp
+ *
+ * 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.
+ */
+
+#include <linux/export.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/seq_file.h>
+#include <linux/ioport.h>
+#include <linux/console.h>
+#include <linux/utsname.h>
+#include <linux/tty.h>
+#include <linux/root_dev.h>
+#include <linux/notifier.h>
+#include <linux/cpu.h>
+#include <linux/unistd.h>
+#include <linux/serial.h>
+#include <linux/serial_8250.h>
+#include <linux/bootmem.h>
+#include <linux/pci.h>
+#include <linux/lockdep.h>
+#include <linux/memblock.h>
+#include <linux/memory.h>
+#include <linux/nmi.h>
+
+#include <asm/debugfs.h>
+#include <asm/io.h>
+#include <asm/kdump.h>
+#include <asm/prom.h>
+#include <asm/processor.h>
+#include <asm/pgtable.h>
+#include <asm/smp.h>
+#include <asm/elf.h>
+#include <asm/machdep.h>
+#include <asm/paca.h>
+#include <asm/time.h>
+#include <asm/cputable.h>
+#include <asm/dt_cpu_ftrs.h>
+#include <asm/sections.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/firmware.h>
+#include <asm/xmon.h>
+#include <asm/udbg.h>
+#include <asm/kexec.h>
+#include <asm/code-patching.h>
+#include <asm/livepatch.h>
+#include <asm/opal.h>
+#include <asm/cputhreads.h>
+#include <asm/hw_irq.h>
+#include <asm/feature-fixups.h>
+
+#include "setup.h"
+
+#ifdef DEBUG
+#define DBG(fmt...) udbg_printf(fmt)
+#else
+#define DBG(fmt...)
+#endif
+
+int spinning_secondaries;
+u64 ppc64_pft_size;
+
+struct ppc64_caches ppc64_caches = {
+ .l1d = {
+ .block_size = 0x40,
+ .log_block_size = 6,
+ },
+ .l1i = {
+ .block_size = 0x40,
+ .log_block_size = 6
+ },
+};
+EXPORT_SYMBOL_GPL(ppc64_caches);
+
+#if defined(CONFIG_PPC_BOOK3E) && defined(CONFIG_SMP)
+void __init setup_tlb_core_data(void)
+{
+ int cpu;
+
+ BUILD_BUG_ON(offsetof(struct tlb_core_data, lock) != 0);
+
+ for_each_possible_cpu(cpu) {
+ int first = cpu_first_thread_sibling(cpu);
+
+ /*
+ * If we boot via kdump on a non-primary thread,
+ * make sure we point at the thread that actually
+ * set up this TLB.
+ */
+ if (cpu_first_thread_sibling(boot_cpuid) == first)
+ first = boot_cpuid;
+
+ paca_ptrs[cpu]->tcd_ptr = &paca_ptrs[first]->tcd;
+
+ /*
+ * If we have threads, we need either tlbsrx.
+ * or e6500 tablewalk mode, or else TLB handlers
+ * will be racy and could produce duplicate entries.
+ * Should we panic instead?
+ */
+ WARN_ONCE(smt_enabled_at_boot >= 2 &&
+ !mmu_has_feature(MMU_FTR_USE_TLBRSRV) &&
+ book3e_htw_mode != PPC_HTW_E6500,
+ "%s: unsupported MMU configuration\n", __func__);
+ }
+}
+#endif
+
+#ifdef CONFIG_SMP
+
+static char *smt_enabled_cmdline;
+
+/* Look for ibm,smt-enabled OF option */
+void __init check_smt_enabled(void)
+{
+ struct device_node *dn;
+ const char *smt_option;
+
+ /* Default to enabling all threads */
+ smt_enabled_at_boot = threads_per_core;
+
+ /* Allow the command line to overrule the OF option */
+ if (smt_enabled_cmdline) {
+ if (!strcmp(smt_enabled_cmdline, "on"))
+ smt_enabled_at_boot = threads_per_core;
+ else if (!strcmp(smt_enabled_cmdline, "off"))
+ smt_enabled_at_boot = 0;
+ else {
+ int smt;
+ int rc;
+
+ rc = kstrtoint(smt_enabled_cmdline, 10, &smt);
+ if (!rc)
+ smt_enabled_at_boot =
+ min(threads_per_core, smt);
+ }
+ } else {
+ dn = of_find_node_by_path("/options");
+ if (dn) {
+ smt_option = of_get_property(dn, "ibm,smt-enabled",
+ NULL);
+
+ if (smt_option) {
+ if (!strcmp(smt_option, "on"))
+ smt_enabled_at_boot = threads_per_core;
+ else if (!strcmp(smt_option, "off"))
+ smt_enabled_at_boot = 0;
+ }
+
+ of_node_put(dn);
+ }
+ }
+}
+
+/* Look for smt-enabled= cmdline option */
+static int __init early_smt_enabled(char *p)
+{
+ smt_enabled_cmdline = p;
+ return 0;
+}
+early_param("smt-enabled", early_smt_enabled);
+
+#endif /* CONFIG_SMP */
+
+/** Fix up paca fields required for the boot cpu */
+static void __init fixup_boot_paca(void)
+{
+ /* The boot cpu is started */
+ get_paca()->cpu_start = 1;
+ /* Allow percpu accesses to work until we setup percpu data */
+ get_paca()->data_offset = 0;
+ /* Mark interrupts disabled in PACA */
+ irq_soft_mask_set(IRQS_DISABLED);
+}
+
+static void __init configure_exceptions(void)
+{
+ /*
+ * Setup the trampolines from the lowmem exception vectors
+ * to the kdump kernel when not using a relocatable kernel.
+ */
+ setup_kdump_trampoline();
+
+ /* Under a PAPR hypervisor, we need hypercalls */
+ if (firmware_has_feature(FW_FEATURE_SET_MODE)) {
+ /* Enable AIL if possible */
+ pseries_enable_reloc_on_exc();
+
+ /*
+ * Tell the hypervisor that we want our exceptions to
+ * be taken in little endian mode.
+ *
+ * We don't call this for big endian as our calling convention
+ * makes us always enter in BE, and the call may fail under
+ * some circumstances with kdump.
+ */
+#ifdef __LITTLE_ENDIAN__
+ pseries_little_endian_exceptions();
+#endif
+ } else {
+ /* Set endian mode using OPAL */
+ if (firmware_has_feature(FW_FEATURE_OPAL))
+ opal_configure_cores();
+
+ /* AIL on native is done in cpu_ready_for_interrupts() */
+ }
+}
+
+static void cpu_ready_for_interrupts(void)
+{
+ /*
+ * Enable AIL if supported, and we are in hypervisor mode. This
+ * is called once for every processor.
+ *
+ * If we are not in hypervisor mode the job is done once for
+ * the whole partition in configure_exceptions().
+ */
+ if (cpu_has_feature(CPU_FTR_HVMODE) &&
+ cpu_has_feature(CPU_FTR_ARCH_207S)) {
+ unsigned long lpcr = mfspr(SPRN_LPCR);
+ mtspr(SPRN_LPCR, lpcr | LPCR_AIL_3);
+ }
+
+ /*
+ * Set HFSCR:TM based on CPU features:
+ * In the special case of TM no suspend (P9N DD2.1), Linux is
+ * told TM is off via the dt-ftrs but told to (partially) use
+ * it via OPAL_REINIT_CPUS_TM_SUSPEND_DISABLED. So HFSCR[TM]
+ * will be off from dt-ftrs but we need to turn it on for the
+ * no suspend case.
+ */
+ if (cpu_has_feature(CPU_FTR_HVMODE)) {
+ if (cpu_has_feature(CPU_FTR_TM_COMP))
+ mtspr(SPRN_HFSCR, mfspr(SPRN_HFSCR) | HFSCR_TM);
+ else
+ mtspr(SPRN_HFSCR, mfspr(SPRN_HFSCR) & ~HFSCR_TM);
+ }
+
+ /* Set IR and DR in PACA MSR */
+ get_paca()->kernel_msr = MSR_KERNEL;
+}
+
+unsigned long spr_default_dscr = 0;
+
+void __init record_spr_defaults(void)
+{
+ if (early_cpu_has_feature(CPU_FTR_DSCR))
+ spr_default_dscr = mfspr(SPRN_DSCR);
+}
+
+/*
+ * Early initialization entry point. This is called by head.S
+ * with MMU translation disabled. We rely on the "feature" of
+ * the CPU that ignores the top 2 bits of the address in real
+ * mode so we can access kernel globals normally provided we
+ * only toy with things in the RMO region. From here, we do
+ * some early parsing of the device-tree to setup out MEMBLOCK
+ * data structures, and allocate & initialize the hash table
+ * and segment tables so we can start running with translation
+ * enabled.
+ *
+ * It is this function which will call the probe() callback of
+ * the various platform types and copy the matching one to the
+ * global ppc_md structure. Your platform can eventually do
+ * some very early initializations from the probe() routine, but
+ * this is not recommended, be very careful as, for example, the
+ * device-tree is not accessible via normal means at this point.
+ */
+
+void __init early_setup(unsigned long dt_ptr)
+{
+ static __initdata struct paca_struct boot_paca;
+
+ /* -------- printk is _NOT_ safe to use here ! ------- */
+
+ /* Try new device tree based feature discovery ... */
+ if (!dt_cpu_ftrs_init(__va(dt_ptr)))
+ /* Otherwise use the old style CPU table */
+ identify_cpu(0, mfspr(SPRN_PVR));
+
+ /* Assume we're on cpu 0 for now. Don't write to the paca yet! */
+ initialise_paca(&boot_paca, 0);
+ setup_paca(&boot_paca);
+ fixup_boot_paca();
+
+ /* -------- printk is now safe to use ------- */
+
+ /* Enable early debugging if any specified (see udbg.h) */
+ udbg_early_init();
+
+ DBG(" -> early_setup(), dt_ptr: 0x%lx\n", dt_ptr);
+
+ /*
+ * Do early initialization using the flattened device
+ * tree, such as retrieving the physical memory map or
+ * calculating/retrieving the hash table size.
+ */
+ early_init_devtree(__va(dt_ptr));
+
+ /* Now we know the logical id of our boot cpu, setup the paca. */
+ if (boot_cpuid != 0) {
+ /* Poison paca_ptrs[0] again if it's not the boot cpu */
+ memset(&paca_ptrs[0], 0x88, sizeof(paca_ptrs[0]));
+ }
+ setup_paca(paca_ptrs[boot_cpuid]);
+ fixup_boot_paca();
+
+ /*
+ * Configure exception handlers. This include setting up trampolines
+ * if needed, setting exception endian mode, etc...
+ */
+ configure_exceptions();
+
+ /* Apply all the dynamic patching */
+ apply_feature_fixups();
+ setup_feature_keys();
+
+ /* Initialize the hash table or TLB handling */
+ early_init_mmu();
+
+ /*
+ * After firmware and early platform setup code has set things up,
+ * we note the SPR values for configurable control/performance
+ * registers, and use those as initial defaults.
+ */
+ record_spr_defaults();
+
+ /*
+ * At this point, we can let interrupts switch to virtual mode
+ * (the MMU has been setup), so adjust the MSR in the PACA to
+ * have IR and DR set and enable AIL if it exists
+ */
+ cpu_ready_for_interrupts();
+
+ /*
+ * We enable ftrace here, but since we only support DYNAMIC_FTRACE, it
+ * will only actually get enabled on the boot cpu much later once
+ * ftrace itself has been initialized.
+ */
+ this_cpu_enable_ftrace();
+
+ DBG(" <- early_setup()\n");
+
+#ifdef CONFIG_PPC_EARLY_DEBUG_BOOTX
+ /*
+ * This needs to be done *last* (after the above DBG() even)
+ *
+ * Right after we return from this function, we turn on the MMU
+ * which means the real-mode access trick that btext does will
+ * no longer work, it needs to switch to using a real MMU
+ * mapping. This call will ensure that it does
+ */
+ btext_map();
+#endif /* CONFIG_PPC_EARLY_DEBUG_BOOTX */
+}
+
+#ifdef CONFIG_SMP
+void early_setup_secondary(void)
+{
+ /* Mark interrupts disabled in PACA */
+ irq_soft_mask_set(IRQS_DISABLED);
+
+ /* Initialize the hash table or TLB handling */
+ early_init_mmu_secondary();
+
+ /*
+ * At this point, we can let interrupts switch to virtual mode
+ * (the MMU has been setup), so adjust the MSR in the PACA to
+ * have IR and DR set.
+ */
+ cpu_ready_for_interrupts();
+}
+
+#endif /* CONFIG_SMP */
+
+void panic_smp_self_stop(void)
+{
+ hard_irq_disable();
+ spin_begin();
+ while (1)
+ spin_cpu_relax();
+}
+
+#if defined(CONFIG_SMP) || defined(CONFIG_KEXEC_CORE)
+static bool use_spinloop(void)
+{
+ if (IS_ENABLED(CONFIG_PPC_BOOK3S)) {
+ /*
+ * See comments in head_64.S -- not all platforms insert
+ * secondaries at __secondary_hold and wait at the spin
+ * loop.
+ */
+ if (firmware_has_feature(FW_FEATURE_OPAL))
+ return false;
+ return true;
+ }
+
+ /*
+ * When book3e boots from kexec, the ePAPR spin table does
+ * not get used.
+ */
+ return of_property_read_bool(of_chosen, "linux,booted-from-kexec");
+}
+
+void smp_release_cpus(void)
+{
+ unsigned long *ptr;
+ int i;
+
+ if (!use_spinloop())
+ return;
+
+ DBG(" -> smp_release_cpus()\n");
+
+ /* All secondary cpus are spinning on a common spinloop, release them
+ * all now so they can start to spin on their individual paca
+ * spinloops. For non SMP kernels, the secondary cpus never get out
+ * of the common spinloop.
+ */
+
+ ptr = (unsigned long *)((unsigned long)&__secondary_hold_spinloop
+ - PHYSICAL_START);
+ *ptr = ppc_function_entry(generic_secondary_smp_init);
+
+ /* And wait a bit for them to catch up */
+ for (i = 0; i < 100000; i++) {
+ mb();
+ HMT_low();
+ if (spinning_secondaries == 0)
+ break;
+ udelay(1);
+ }
+ DBG("spinning_secondaries = %d\n", spinning_secondaries);
+
+ DBG(" <- smp_release_cpus()\n");
+}
+#endif /* CONFIG_SMP || CONFIG_KEXEC_CORE */
+
+/*
+ * Initialize some remaining members of the ppc64_caches and systemcfg
+ * structures
+ * (at least until we get rid of them completely). This is mostly some
+ * cache informations about the CPU that will be used by cache flush
+ * routines and/or provided to userland
+ */
+
+static void init_cache_info(struct ppc_cache_info *info, u32 size, u32 lsize,
+ u32 bsize, u32 sets)
+{
+ info->size = size;
+ info->sets = sets;
+ info->line_size = lsize;
+ info->block_size = bsize;
+ info->log_block_size = __ilog2(bsize);
+ if (bsize)
+ info->blocks_per_page = PAGE_SIZE / bsize;
+ else
+ info->blocks_per_page = 0;
+
+ if (sets == 0)
+ info->assoc = 0xffff;
+ else
+ info->assoc = size / (sets * lsize);
+}
+
+static bool __init parse_cache_info(struct device_node *np,
+ bool icache,
+ struct ppc_cache_info *info)
+{
+ static const char *ipropnames[] __initdata = {
+ "i-cache-size",
+ "i-cache-sets",
+ "i-cache-block-size",
+ "i-cache-line-size",
+ };
+ static const char *dpropnames[] __initdata = {
+ "d-cache-size",
+ "d-cache-sets",
+ "d-cache-block-size",
+ "d-cache-line-size",
+ };
+ const char **propnames = icache ? ipropnames : dpropnames;
+ const __be32 *sizep, *lsizep, *bsizep, *setsp;
+ u32 size, lsize, bsize, sets;
+ bool success = true;
+
+ size = 0;
+ sets = -1u;
+ lsize = bsize = cur_cpu_spec->dcache_bsize;
+ sizep = of_get_property(np, propnames[0], NULL);
+ if (sizep != NULL)
+ size = be32_to_cpu(*sizep);
+ setsp = of_get_property(np, propnames[1], NULL);
+ if (setsp != NULL)
+ sets = be32_to_cpu(*setsp);
+ bsizep = of_get_property(np, propnames[2], NULL);
+ lsizep = of_get_property(np, propnames[3], NULL);
+ if (bsizep == NULL)
+ bsizep = lsizep;
+ if (lsizep != NULL)
+ lsize = be32_to_cpu(*lsizep);
+ if (bsizep != NULL)
+ bsize = be32_to_cpu(*bsizep);
+ if (sizep == NULL || bsizep == NULL || lsizep == NULL)
+ success = false;
+
+ /*
+ * OF is weird .. it represents fully associative caches
+ * as "1 way" which doesn't make much sense and doesn't
+ * leave room for direct mapped. We'll assume that 0
+ * in OF means direct mapped for that reason.
+ */
+ if (sets == 1)
+ sets = 0;
+ else if (sets == 0)
+ sets = 1;
+
+ init_cache_info(info, size, lsize, bsize, sets);
+
+ return success;
+}
+
+void __init initialize_cache_info(void)
+{
+ struct device_node *cpu = NULL, *l2, *l3 = NULL;
+ u32 pvr;
+
+ DBG(" -> initialize_cache_info()\n");
+
+ /*
+ * All shipping POWER8 machines have a firmware bug that
+ * puts incorrect information in the device-tree. This will
+ * be (hopefully) fixed for future chips but for now hard
+ * code the values if we are running on one of these
+ */
+ pvr = PVR_VER(mfspr(SPRN_PVR));
+ if (pvr == PVR_POWER8 || pvr == PVR_POWER8E ||
+ pvr == PVR_POWER8NVL) {
+ /* size lsize blk sets */
+ init_cache_info(&ppc64_caches.l1i, 0x8000, 128, 128, 32);
+ init_cache_info(&ppc64_caches.l1d, 0x10000, 128, 128, 64);
+ init_cache_info(&ppc64_caches.l2, 0x80000, 128, 0, 512);
+ init_cache_info(&ppc64_caches.l3, 0x800000, 128, 0, 8192);
+ } else
+ cpu = of_find_node_by_type(NULL, "cpu");
+
+ /*
+ * We're assuming *all* of the CPUs have the same
+ * d-cache and i-cache sizes... -Peter
+ */
+ if (cpu) {
+ if (!parse_cache_info(cpu, false, &ppc64_caches.l1d))
+ DBG("Argh, can't find dcache properties !\n");
+
+ if (!parse_cache_info(cpu, true, &ppc64_caches.l1i))
+ DBG("Argh, can't find icache properties !\n");
+
+ /*
+ * Try to find the L2 and L3 if any. Assume they are
+ * unified and use the D-side properties.
+ */
+ l2 = of_find_next_cache_node(cpu);
+ of_node_put(cpu);
+ if (l2) {
+ parse_cache_info(l2, false, &ppc64_caches.l2);
+ l3 = of_find_next_cache_node(l2);
+ of_node_put(l2);
+ }
+ if (l3) {
+ parse_cache_info(l3, false, &ppc64_caches.l3);
+ of_node_put(l3);
+ }
+ }
+
+ /* For use by binfmt_elf */
+ dcache_bsize = ppc64_caches.l1d.block_size;
+ icache_bsize = ppc64_caches.l1i.block_size;
+
+ cur_cpu_spec->dcache_bsize = dcache_bsize;
+ cur_cpu_spec->icache_bsize = icache_bsize;
+
+ DBG(" <- initialize_cache_info()\n");
+}
+
+/*
+ * This returns the limit below which memory accesses to the linear
+ * mapping are guarnateed not to cause an architectural exception (e.g.,
+ * TLB or SLB miss fault).
+ *
+ * This is used to allocate PACAs and various interrupt stacks that
+ * that are accessed early in interrupt handlers that must not cause
+ * re-entrant interrupts.
+ */
+__init u64 ppc64_bolted_size(void)
+{
+#ifdef CONFIG_PPC_BOOK3E
+ /* Freescale BookE bolts the entire linear mapping */
+ /* XXX: BookE ppc64_rma_limit setup seems to disagree? */
+ if (early_mmu_has_feature(MMU_FTR_TYPE_FSL_E))
+ return linear_map_top;
+ /* Other BookE, we assume the first GB is bolted */
+ return 1ul << 30;
+#else
+ /* BookS radix, does not take faults on linear mapping */
+ if (early_radix_enabled())
+ return ULONG_MAX;
+
+ /* BookS hash, the first segment is bolted */
+ if (early_mmu_has_feature(MMU_FTR_1T_SEGMENT))
+ return 1UL << SID_SHIFT_1T;
+ return 1UL << SID_SHIFT;
+#endif
+}
+
+static void *__init alloc_stack(unsigned long limit, int cpu)
+{
+ unsigned long pa;
+
+ pa = memblock_alloc_base_nid(THREAD_SIZE, THREAD_SIZE, limit,
+ early_cpu_to_node(cpu), MEMBLOCK_NONE);
+ if (!pa) {
+ pa = memblock_alloc_base(THREAD_SIZE, THREAD_SIZE, limit);
+ if (!pa)
+ panic("cannot allocate stacks");
+ }
+
+ return __va(pa);
+}
+
+void __init irqstack_early_init(void)
+{
+ u64 limit = ppc64_bolted_size();
+ unsigned int i;
+
+ /*
+ * Interrupt stacks must be in the first segment since we
+ * cannot afford to take SLB misses on them. They are not
+ * accessed in realmode.
+ */
+ for_each_possible_cpu(i) {
+ softirq_ctx[i] = alloc_stack(limit, i);
+ hardirq_ctx[i] = alloc_stack(limit, i);
+ }
+}
+
+#ifdef CONFIG_PPC_BOOK3E
+void __init exc_lvl_early_init(void)
+{
+ unsigned int i;
+
+ for_each_possible_cpu(i) {
+ void *sp;
+
+ sp = alloc_stack(ULONG_MAX, i);
+ critirq_ctx[i] = sp;
+ paca_ptrs[i]->crit_kstack = sp + THREAD_SIZE;
+
+ sp = alloc_stack(ULONG_MAX, i);
+ dbgirq_ctx[i] = sp;
+ paca_ptrs[i]->dbg_kstack = sp + THREAD_SIZE;
+
+ sp = alloc_stack(ULONG_MAX, i);
+ mcheckirq_ctx[i] = sp;
+ paca_ptrs[i]->mc_kstack = sp + THREAD_SIZE;
+ }
+
+ if (cpu_has_feature(CPU_FTR_DEBUG_LVL_EXC))
+ patch_exception(0x040, exc_debug_debug_book3e);
+}
+#endif
+
+/*
+ * Emergency stacks are used for a range of things, from asynchronous
+ * NMIs (system reset, machine check) to synchronous, process context.
+ * We set preempt_count to zero, even though that isn't necessarily correct. To
+ * get the right value we'd need to copy it from the previous thread_info, but
+ * doing that might fault causing more problems.
+ * TODO: what to do with accounting?
+ */
+static void emerg_stack_init_thread_info(struct thread_info *ti, int cpu)
+{
+ ti->task = NULL;
+ ti->cpu = cpu;
+ ti->preempt_count = 0;
+ ti->local_flags = 0;
+ ti->flags = 0;
+ klp_init_thread_info(ti);
+}
+
+/*
+ * Stack space used when we detect a bad kernel stack pointer, and
+ * early in SMP boots before relocation is enabled. Exclusive emergency
+ * stack for machine checks.
+ */
+void __init emergency_stack_init(void)
+{
+ u64 limit;
+ unsigned int i;
+
+ /*
+ * Emergency stacks must be under 256MB, we cannot afford to take
+ * SLB misses on them. The ABI also requires them to be 128-byte
+ * aligned.
+ *
+ * Since we use these as temporary stacks during secondary CPU
+ * bringup, machine check, system reset, and HMI, we need to get
+ * at them in real mode. This means they must also be within the RMO
+ * region.
+ *
+ * The IRQ stacks allocated elsewhere in this file are zeroed and
+ * initialized in kernel/irq.c. These are initialized here in order
+ * to have emergency stacks available as early as possible.
+ */
+ limit = min(ppc64_bolted_size(), ppc64_rma_size);
+
+ for_each_possible_cpu(i) {
+ struct thread_info *ti;
+
+ ti = alloc_stack(limit, i);
+ memset(ti, 0, THREAD_SIZE);
+ emerg_stack_init_thread_info(ti, i);
+ paca_ptrs[i]->emergency_sp = (void *)ti + THREAD_SIZE;
+
+#ifdef CONFIG_PPC_BOOK3S_64
+ /* emergency stack for NMI exception handling. */
+ ti = alloc_stack(limit, i);
+ memset(ti, 0, THREAD_SIZE);
+ emerg_stack_init_thread_info(ti, i);
+ paca_ptrs[i]->nmi_emergency_sp = (void *)ti + THREAD_SIZE;
+
+ /* emergency stack for machine check exception handling. */
+ ti = alloc_stack(limit, i);
+ memset(ti, 0, THREAD_SIZE);
+ emerg_stack_init_thread_info(ti, i);
+ paca_ptrs[i]->mc_emergency_sp = (void *)ti + THREAD_SIZE;
+#endif
+ }
+}
+
+#ifdef CONFIG_SMP
+#define PCPU_DYN_SIZE ()
+
+static void * __init pcpu_fc_alloc(unsigned int cpu, size_t size, size_t align)
+{
+ return __alloc_bootmem_node(NODE_DATA(early_cpu_to_node(cpu)), size, align,
+ __pa(MAX_DMA_ADDRESS));
+}
+
+static void __init pcpu_fc_free(void *ptr, size_t size)
+{
+ free_bootmem(__pa(ptr), size);
+}
+
+static int pcpu_cpu_distance(unsigned int from, unsigned int to)
+{
+ if (early_cpu_to_node(from) == early_cpu_to_node(to))
+ return LOCAL_DISTANCE;
+ else
+ return REMOTE_DISTANCE;
+}
+
+unsigned long __per_cpu_offset[NR_CPUS] __read_mostly;
+EXPORT_SYMBOL(__per_cpu_offset);
+
+void __init setup_per_cpu_areas(void)
+{
+ const size_t dyn_size = PERCPU_MODULE_RESERVE + PERCPU_DYNAMIC_RESERVE;
+ size_t atom_size;
+ unsigned long delta;
+ unsigned int cpu;
+ int rc;
+
+ /*
+ * Linear mapping is one of 4K, 1M and 16M. For 4K, no need
+ * to group units. For larger mappings, use 1M atom which
+ * should be large enough to contain a number of units.
+ */
+ if (mmu_linear_psize == MMU_PAGE_4K)
+ atom_size = PAGE_SIZE;
+ else
+ atom_size = 1 << 20;
+
+ rc = pcpu_embed_first_chunk(0, dyn_size, atom_size, pcpu_cpu_distance,
+ pcpu_fc_alloc, pcpu_fc_free);
+ if (rc < 0)
+ panic("cannot initialize percpu area (err=%d)", rc);
+
+ delta = (unsigned long)pcpu_base_addr - (unsigned long)__per_cpu_start;
+ for_each_possible_cpu(cpu) {
+ __per_cpu_offset[cpu] = delta + pcpu_unit_offsets[cpu];
+ paca_ptrs[cpu]->data_offset = __per_cpu_offset[cpu];
+ }
+}
+#endif
+
+#ifdef CONFIG_MEMORY_HOTPLUG_SPARSE
+unsigned long memory_block_size_bytes(void)
+{
+ if (ppc_md.memory_block_size)
+ return ppc_md.memory_block_size();
+
+ return MIN_MEMORY_BLOCK_SIZE;
+}
+#endif
+
+#if defined(CONFIG_PPC_INDIRECT_PIO) || defined(CONFIG_PPC_INDIRECT_MMIO)
+struct ppc_pci_io ppc_pci_io;
+EXPORT_SYMBOL(ppc_pci_io);
+#endif
+
+#ifdef CONFIG_HARDLOCKUP_DETECTOR_PERF
+u64 hw_nmi_get_sample_period(int watchdog_thresh)
+{
+ return ppc_proc_freq * watchdog_thresh;
+}
+#endif
+
+/*
+ * The perf based hardlockup detector breaks PMU event based branches, so
+ * disable it by default. Book3S has a soft-nmi hardlockup detector based
+ * on the decrementer interrupt, so it does not suffer from this problem.
+ *
+ * It is likely to get false positives in VM guests, so disable it there
+ * by default too.
+ */
+static int __init disable_hardlockup_detector(void)
+{
+#ifdef CONFIG_HARDLOCKUP_DETECTOR_PERF
+ hardlockup_detector_disable();
+#else
+ if (firmware_has_feature(FW_FEATURE_LPAR))
+ hardlockup_detector_disable();
+#endif
+
+ return 0;
+}
+early_initcall(disable_hardlockup_detector);
+
+#ifdef CONFIG_PPC_BOOK3S_64
+static enum l1d_flush_type enabled_flush_types;
+static void *l1d_flush_fallback_area;
+static bool no_rfi_flush;
+bool rfi_flush;
+
+static int __init handle_no_rfi_flush(char *p)
+{
+ pr_info("rfi-flush: disabled on command line.");
+ no_rfi_flush = true;
+ return 0;
+}
+early_param("no_rfi_flush", handle_no_rfi_flush);
+
+/*
+ * The RFI flush is not KPTI, but because users will see doco that says to use
+ * nopti we hijack that option here to also disable the RFI flush.
+ */
+static int __init handle_no_pti(char *p)
+{
+ pr_info("rfi-flush: disabling due to 'nopti' on command line.\n");
+ handle_no_rfi_flush(NULL);
+ return 0;
+}
+early_param("nopti", handle_no_pti);
+
+static void do_nothing(void *unused)
+{
+ /*
+ * We don't need to do the flush explicitly, just enter+exit kernel is
+ * sufficient, the RFI exit handlers will do the right thing.
+ */
+}
+
+void rfi_flush_enable(bool enable)
+{
+ if (enable) {
+ do_rfi_flush_fixups(enabled_flush_types);
+ on_each_cpu(do_nothing, NULL, 1);
+ } else
+ do_rfi_flush_fixups(L1D_FLUSH_NONE);
+
+ rfi_flush = enable;
+}
+
+static void __ref init_fallback_flush(void)
+{
+ u64 l1d_size, limit;
+ int cpu;
+
+ /* Only allocate the fallback flush area once (at boot time). */
+ if (l1d_flush_fallback_area)
+ return;
+
+ l1d_size = ppc64_caches.l1d.size;
+
+ /*
+ * If there is no d-cache-size property in the device tree, l1d_size
+ * could be zero. That leads to the loop in the asm wrapping around to
+ * 2^64-1, and then walking off the end of the fallback area and
+ * eventually causing a page fault which is fatal. Just default to
+ * something vaguely sane.
+ */
+ if (!l1d_size)
+ l1d_size = (64 * 1024);
+
+ limit = min(ppc64_bolted_size(), ppc64_rma_size);
+
+ /*
+ * Align to L1d size, and size it at 2x L1d size, to catch possible
+ * hardware prefetch runoff. We don't have a recipe for load patterns to
+ * reliably avoid the prefetcher.
+ */
+ l1d_flush_fallback_area = __va(memblock_alloc_base(l1d_size * 2, l1d_size, limit));
+ memset(l1d_flush_fallback_area, 0, l1d_size * 2);
+
+ for_each_possible_cpu(cpu) {
+ struct paca_struct *paca = paca_ptrs[cpu];
+ paca->rfi_flush_fallback_area = l1d_flush_fallback_area;
+ paca->l1d_flush_size = l1d_size;
+ }
+}
+
+void setup_rfi_flush(enum l1d_flush_type types, bool enable)
+{
+ if (types & L1D_FLUSH_FALLBACK) {
+ pr_info("rfi-flush: fallback displacement flush available\n");
+ init_fallback_flush();
+ }
+
+ if (types & L1D_FLUSH_ORI)
+ pr_info("rfi-flush: ori type flush available\n");
+
+ if (types & L1D_FLUSH_MTTRIG)
+ pr_info("rfi-flush: mttrig type flush available\n");
+
+ enabled_flush_types = types;
+
+ if (!no_rfi_flush)
+ rfi_flush_enable(enable);
+}
+
+#ifdef CONFIG_DEBUG_FS
+static int rfi_flush_set(void *data, u64 val)
+{
+ bool enable;
+
+ if (val == 1)
+ enable = true;
+ else if (val == 0)
+ enable = false;
+ else
+ return -EINVAL;
+
+ /* Only do anything if we're changing state */
+ if (enable != rfi_flush)
+ rfi_flush_enable(enable);
+
+ return 0;
+}
+
+static int rfi_flush_get(void *data, u64 *val)
+{
+ *val = rfi_flush ? 1 : 0;
+ return 0;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(fops_rfi_flush, rfi_flush_get, rfi_flush_set, "%llu\n");
+
+static __init int rfi_flush_debugfs_init(void)
+{
+ debugfs_create_file("rfi_flush", 0600, powerpc_debugfs_root, NULL, &fops_rfi_flush);
+ return 0;
+}
+device_initcall(rfi_flush_debugfs_init);
+#endif
+#endif /* CONFIG_PPC_BOOK3S_64 */