/* * * 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. */ #define DEBUG #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef DEBUG #define DBG(fmt...) udbg_printf(fmt) #else #define DBG(fmt...) #endif int spinning_secondaries; u64 ppc64_pft_size; /* Pick defaults since we might want to patch instructions * before we've read this from the device tree. */ struct ppc64_caches ppc64_caches = { .dline_size = 0x40, .log_dline_size = 6, .iline_size = 0x40, .log_iline_size = 6 }; EXPORT_SYMBOL_GPL(ppc64_caches); /* * 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; int ucache_bsize; #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[cpu].tcd_ptr = &paca[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. */ if (smt_enabled_at_boot >= 2 && !mmu_has_feature(MMU_FTR_USE_TLBRSRV) && book3e_htw_mode != PPC_HTW_E6500) { /* Should we panic instead? */ WARN_ONCE("%s: unsupported MMU configuration -- expect problems\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; } 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(); /* Enable AIL if supported, and we are in hypervisor mode */ if (early_cpu_has_feature(CPU_FTR_HVMODE) && early_cpu_has_feature(CPU_FTR_ARCH_207S)) { unsigned long lpcr = mfspr(SPRN_LPCR); mtspr(SPRN_LPCR, lpcr | LPCR_AIL_3); } } } static void cpu_ready_for_interrupts(void) { /* Set IR and DR in PACA MSR */ get_paca()->kernel_msr = MSR_KERNEL; } /* * 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 ! ------- */ /* Identify CPU type */ 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. */ setup_paca(&paca[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(); /* Initialize the hash table or TLB handling */ early_init_mmu(); /* * 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(); 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 */ get_paca()->soft_enabled = 0; /* 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 */ #if defined(CONFIG_SMP) || defined(CONFIG_KEXEC) static bool use_spinloop(void) { if (!IS_ENABLED(CONFIG_PPC_BOOK3E)) 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 */ /* * 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 */ void __init initialize_cache_info(void) { struct device_node *np; unsigned long num_cpus = 0; DBG(" -> initialize_cache_info()\n"); for_each_node_by_type(np, "cpu") { num_cpus += 1; /* * We're assuming *all* of the CPUs have the same * d-cache and i-cache sizes... -Peter */ if (num_cpus == 1) { const __be32 *sizep, *lsizep; u32 size, lsize; size = 0; lsize = cur_cpu_spec->dcache_bsize; sizep = of_get_property(np, "d-cache-size", NULL); if (sizep != NULL) size = be32_to_cpu(*sizep); lsizep = of_get_property(np, "d-cache-block-size", NULL); /* fallback if block size missing */ if (lsizep == NULL) lsizep = of_get_property(np, "d-cache-line-size", NULL); if (lsizep != NULL) lsize = be32_to_cpu(*lsizep); if (sizep == NULL || lsizep == NULL) DBG("Argh, can't find dcache properties ! " "sizep: %p, lsizep: %p\n", sizep, lsizep); ppc64_caches.dsize = size; ppc64_caches.dline_size = lsize; ppc64_caches.log_dline_size = __ilog2(lsize); ppc64_caches.dlines_per_page = PAGE_SIZE / lsize; size = 0; lsize = cur_cpu_spec->icache_bsize; sizep = of_get_property(np, "i-cache-size", NULL); if (sizep != NULL) size = be32_to_cpu(*sizep); lsizep = of_get_property(np, "i-cache-block-size", NULL); if (lsizep == NULL) lsizep = of_get_property(np, "i-cache-line-size", NULL); if (lsizep != NULL) lsize = be32_to_cpu(*lsizep); if (sizep == NULL || lsizep == NULL) DBG("Argh, can't find icache properties ! " "sizep: %p, lsizep: %p\n", sizep, lsizep); ppc64_caches.isize = size; ppc64_caches.iline_size = lsize; ppc64_caches.log_iline_size = __ilog2(lsize); ppc64_caches.ilines_per_page = PAGE_SIZE / lsize; } } /* For use by binfmt_elf */ dcache_bsize = ppc64_caches.dline_size; icache_bsize = ppc64_caches.iline_size; DBG(" <- initialize_cache_info()\n"); } /* This returns the limit below which memory accesses to the linear * mapping are guarnateed not to cause a TLB or SLB miss. This is * used to allocate interrupt or emergency stacks for which our * exception entry path doesn't deal with being interrupted. */ static __init u64 safe_stack_limit(void) { #ifdef CONFIG_PPC_BOOK3E /* Freescale BookE bolts the entire linear mapping */ if (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, the first segment is bolted */ if (mmu_has_feature(MMU_FTR_1T_SEGMENT)) return 1UL << SID_SHIFT_1T; return 1UL << SID_SHIFT; #endif } void __init irqstack_early_init(void) { u64 limit = safe_stack_limit(); unsigned int i; /* * Interrupt stacks must be in the first segment since we * cannot afford to take SLB misses on them. */ for_each_possible_cpu(i) { softirq_ctx[i] = (struct thread_info *) __va(memblock_alloc_base(THREAD_SIZE, THREAD_SIZE, limit)); hardirq_ctx[i] = (struct thread_info *) __va(memblock_alloc_base(THREAD_SIZE, THREAD_SIZE, limit)); } } #ifdef CONFIG_PPC_BOOK3E void __init exc_lvl_early_init(void) { unsigned int i; unsigned long sp; for_each_possible_cpu(i) { sp = memblock_alloc(THREAD_SIZE, THREAD_SIZE); critirq_ctx[i] = (struct thread_info *)__va(sp); paca[i].crit_kstack = __va(sp + THREAD_SIZE); sp = memblock_alloc(THREAD_SIZE, THREAD_SIZE); dbgirq_ctx[i] = (struct thread_info *)__va(sp); paca[i].dbg_kstack = __va(sp + THREAD_SIZE); sp = memblock_alloc(THREAD_SIZE, THREAD_SIZE); mcheckirq_ctx[i] = (struct thread_info *)__va(sp); paca[i].mc_kstack = __va(sp + THREAD_SIZE); } if (cpu_has_feature(CPU_FTR_DEBUG_LVL_EXC)) patch_exception(0x040, exc_debug_debug_book3e); } #endif /* * 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, we need to get at them in real mode. This means they * must also be within the RMO region. */ limit = min(safe_stack_limit(), ppc64_rma_size); for_each_possible_cpu(i) { struct thread_info *ti; ti = __va(memblock_alloc_base(THREAD_SIZE, THREAD_SIZE, limit)); klp_init_thread_info(ti); paca[i].emergency_sp = (void *)ti + THREAD_SIZE; #ifdef CONFIG_PPC_BOOK3S_64 /* emergency stack for machine check exception handling. */ ti = __va(memblock_alloc_base(THREAD_SIZE, THREAD_SIZE, limit)); klp_init_thread_info(ti); paca[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(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 (cpu_to_node(from) == 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[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 u64 hw_nmi_get_sample_period(int watchdog_thresh) { return ppc_proc_freq * watchdog_thresh; } /* * The hardlockup detector breaks PMU event based branches and is likely * to get false positives in KVM guests, so disable it by default. */ static int __init disable_hardlockup_detector(void) { hardlockup_detector_disable(); return 0; } early_initcall(disable_hardlockup_detector); #endif