arm64: dts: Revert "specify console via command line"
[linux/fpc-iii.git] / arch / powerpc / kernel / setup_64.c
blobe05e6dd67ae6b95244fba873b2d25a0c779850f0
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 *
4 * Common boot and setup code.
6 * Copyright (C) 2001 PPC64 Team, IBM Corp
7 */
9 #include <linux/export.h>
10 #include <linux/string.h>
11 #include <linux/sched.h>
12 #include <linux/init.h>
13 #include <linux/kernel.h>
14 #include <linux/reboot.h>
15 #include <linux/delay.h>
16 #include <linux/initrd.h>
17 #include <linux/seq_file.h>
18 #include <linux/ioport.h>
19 #include <linux/console.h>
20 #include <linux/utsname.h>
21 #include <linux/tty.h>
22 #include <linux/root_dev.h>
23 #include <linux/notifier.h>
24 #include <linux/cpu.h>
25 #include <linux/unistd.h>
26 #include <linux/serial.h>
27 #include <linux/serial_8250.h>
28 #include <linux/memblock.h>
29 #include <linux/pci.h>
30 #include <linux/lockdep.h>
31 #include <linux/memory.h>
32 #include <linux/nmi.h>
34 #include <asm/debugfs.h>
35 #include <asm/io.h>
36 #include <asm/kdump.h>
37 #include <asm/prom.h>
38 #include <asm/processor.h>
39 #include <asm/pgtable.h>
40 #include <asm/smp.h>
41 #include <asm/elf.h>
42 #include <asm/machdep.h>
43 #include <asm/paca.h>
44 #include <asm/time.h>
45 #include <asm/cputable.h>
46 #include <asm/dt_cpu_ftrs.h>
47 #include <asm/sections.h>
48 #include <asm/btext.h>
49 #include <asm/nvram.h>
50 #include <asm/setup.h>
51 #include <asm/rtas.h>
52 #include <asm/iommu.h>
53 #include <asm/serial.h>
54 #include <asm/cache.h>
55 #include <asm/page.h>
56 #include <asm/mmu.h>
57 #include <asm/firmware.h>
58 #include <asm/xmon.h>
59 #include <asm/udbg.h>
60 #include <asm/kexec.h>
61 #include <asm/code-patching.h>
62 #include <asm/livepatch.h>
63 #include <asm/opal.h>
64 #include <asm/cputhreads.h>
65 #include <asm/hw_irq.h>
66 #include <asm/feature-fixups.h>
67 #include <asm/kup.h>
68 #include <asm/early_ioremap.h>
70 #include "setup.h"
72 int spinning_secondaries;
73 u64 ppc64_pft_size;
75 struct ppc64_caches ppc64_caches = {
76 .l1d = {
77 .block_size = 0x40,
78 .log_block_size = 6,
80 .l1i = {
81 .block_size = 0x40,
82 .log_block_size = 6
85 EXPORT_SYMBOL_GPL(ppc64_caches);
87 #if defined(CONFIG_PPC_BOOK3E) && defined(CONFIG_SMP)
88 void __init setup_tlb_core_data(void)
90 int cpu;
92 BUILD_BUG_ON(offsetof(struct tlb_core_data, lock) != 0);
94 for_each_possible_cpu(cpu) {
95 int first = cpu_first_thread_sibling(cpu);
98 * If we boot via kdump on a non-primary thread,
99 * make sure we point at the thread that actually
100 * set up this TLB.
102 if (cpu_first_thread_sibling(boot_cpuid) == first)
103 first = boot_cpuid;
105 paca_ptrs[cpu]->tcd_ptr = &paca_ptrs[first]->tcd;
108 * If we have threads, we need either tlbsrx.
109 * or e6500 tablewalk mode, or else TLB handlers
110 * will be racy and could produce duplicate entries.
111 * Should we panic instead?
113 WARN_ONCE(smt_enabled_at_boot >= 2 &&
114 !mmu_has_feature(MMU_FTR_USE_TLBRSRV) &&
115 book3e_htw_mode != PPC_HTW_E6500,
116 "%s: unsupported MMU configuration\n", __func__);
119 #endif
121 #ifdef CONFIG_SMP
123 static char *smt_enabled_cmdline;
125 /* Look for ibm,smt-enabled OF option */
126 void __init check_smt_enabled(void)
128 struct device_node *dn;
129 const char *smt_option;
131 /* Default to enabling all threads */
132 smt_enabled_at_boot = threads_per_core;
134 /* Allow the command line to overrule the OF option */
135 if (smt_enabled_cmdline) {
136 if (!strcmp(smt_enabled_cmdline, "on"))
137 smt_enabled_at_boot = threads_per_core;
138 else if (!strcmp(smt_enabled_cmdline, "off"))
139 smt_enabled_at_boot = 0;
140 else {
141 int smt;
142 int rc;
144 rc = kstrtoint(smt_enabled_cmdline, 10, &smt);
145 if (!rc)
146 smt_enabled_at_boot =
147 min(threads_per_core, smt);
149 } else {
150 dn = of_find_node_by_path("/options");
151 if (dn) {
152 smt_option = of_get_property(dn, "ibm,smt-enabled",
153 NULL);
155 if (smt_option) {
156 if (!strcmp(smt_option, "on"))
157 smt_enabled_at_boot = threads_per_core;
158 else if (!strcmp(smt_option, "off"))
159 smt_enabled_at_boot = 0;
162 of_node_put(dn);
167 /* Look for smt-enabled= cmdline option */
168 static int __init early_smt_enabled(char *p)
170 smt_enabled_cmdline = p;
171 return 0;
173 early_param("smt-enabled", early_smt_enabled);
175 #endif /* CONFIG_SMP */
177 /** Fix up paca fields required for the boot cpu */
178 static void __init fixup_boot_paca(void)
180 /* The boot cpu is started */
181 get_paca()->cpu_start = 1;
182 /* Allow percpu accesses to work until we setup percpu data */
183 get_paca()->data_offset = 0;
184 /* Mark interrupts disabled in PACA */
185 irq_soft_mask_set(IRQS_DISABLED);
188 static void __init configure_exceptions(void)
191 * Setup the trampolines from the lowmem exception vectors
192 * to the kdump kernel when not using a relocatable kernel.
194 setup_kdump_trampoline();
196 /* Under a PAPR hypervisor, we need hypercalls */
197 if (firmware_has_feature(FW_FEATURE_SET_MODE)) {
198 /* Enable AIL if possible */
199 pseries_enable_reloc_on_exc();
202 * Tell the hypervisor that we want our exceptions to
203 * be taken in little endian mode.
205 * We don't call this for big endian as our calling convention
206 * makes us always enter in BE, and the call may fail under
207 * some circumstances with kdump.
209 #ifdef __LITTLE_ENDIAN__
210 pseries_little_endian_exceptions();
211 #endif
212 } else {
213 /* Set endian mode using OPAL */
214 if (firmware_has_feature(FW_FEATURE_OPAL))
215 opal_configure_cores();
217 /* AIL on native is done in cpu_ready_for_interrupts() */
221 static void cpu_ready_for_interrupts(void)
224 * Enable AIL if supported, and we are in hypervisor mode. This
225 * is called once for every processor.
227 * If we are not in hypervisor mode the job is done once for
228 * the whole partition in configure_exceptions().
230 if (cpu_has_feature(CPU_FTR_HVMODE) &&
231 cpu_has_feature(CPU_FTR_ARCH_207S)) {
232 unsigned long lpcr = mfspr(SPRN_LPCR);
233 mtspr(SPRN_LPCR, lpcr | LPCR_AIL_3);
237 * Set HFSCR:TM based on CPU features:
238 * In the special case of TM no suspend (P9N DD2.1), Linux is
239 * told TM is off via the dt-ftrs but told to (partially) use
240 * it via OPAL_REINIT_CPUS_TM_SUSPEND_DISABLED. So HFSCR[TM]
241 * will be off from dt-ftrs but we need to turn it on for the
242 * no suspend case.
244 if (cpu_has_feature(CPU_FTR_HVMODE)) {
245 if (cpu_has_feature(CPU_FTR_TM_COMP))
246 mtspr(SPRN_HFSCR, mfspr(SPRN_HFSCR) | HFSCR_TM);
247 else
248 mtspr(SPRN_HFSCR, mfspr(SPRN_HFSCR) & ~HFSCR_TM);
251 /* Set IR and DR in PACA MSR */
252 get_paca()->kernel_msr = MSR_KERNEL;
255 unsigned long spr_default_dscr = 0;
257 void __init record_spr_defaults(void)
259 if (early_cpu_has_feature(CPU_FTR_DSCR))
260 spr_default_dscr = mfspr(SPRN_DSCR);
264 * Early initialization entry point. This is called by head.S
265 * with MMU translation disabled. We rely on the "feature" of
266 * the CPU that ignores the top 2 bits of the address in real
267 * mode so we can access kernel globals normally provided we
268 * only toy with things in the RMO region. From here, we do
269 * some early parsing of the device-tree to setup out MEMBLOCK
270 * data structures, and allocate & initialize the hash table
271 * and segment tables so we can start running with translation
272 * enabled.
274 * It is this function which will call the probe() callback of
275 * the various platform types and copy the matching one to the
276 * global ppc_md structure. Your platform can eventually do
277 * some very early initializations from the probe() routine, but
278 * this is not recommended, be very careful as, for example, the
279 * device-tree is not accessible via normal means at this point.
282 void __init early_setup(unsigned long dt_ptr)
284 static __initdata struct paca_struct boot_paca;
286 /* -------- printk is _NOT_ safe to use here ! ------- */
288 /* Try new device tree based feature discovery ... */
289 if (!dt_cpu_ftrs_init(__va(dt_ptr)))
290 /* Otherwise use the old style CPU table */
291 identify_cpu(0, mfspr(SPRN_PVR));
293 /* Assume we're on cpu 0 for now. Don't write to the paca yet! */
294 initialise_paca(&boot_paca, 0);
295 setup_paca(&boot_paca);
296 fixup_boot_paca();
298 /* -------- printk is now safe to use ------- */
300 /* Enable early debugging if any specified (see udbg.h) */
301 udbg_early_init();
303 udbg_printf(" -> %s(), dt_ptr: 0x%lx\n", __func__, dt_ptr);
306 * Do early initialization using the flattened device
307 * tree, such as retrieving the physical memory map or
308 * calculating/retrieving the hash table size.
310 early_init_devtree(__va(dt_ptr));
312 /* Now we know the logical id of our boot cpu, setup the paca. */
313 if (boot_cpuid != 0) {
314 /* Poison paca_ptrs[0] again if it's not the boot cpu */
315 memset(&paca_ptrs[0], 0x88, sizeof(paca_ptrs[0]));
317 setup_paca(paca_ptrs[boot_cpuid]);
318 fixup_boot_paca();
321 * Configure exception handlers. This include setting up trampolines
322 * if needed, setting exception endian mode, etc...
324 configure_exceptions();
327 * Configure Kernel Userspace Protection. This needs to happen before
328 * feature fixups for platforms that implement this using features.
330 setup_kup();
332 /* Apply all the dynamic patching */
333 apply_feature_fixups();
334 setup_feature_keys();
336 early_ioremap_setup();
338 /* Initialize the hash table or TLB handling */
339 early_init_mmu();
342 * After firmware and early platform setup code has set things up,
343 * we note the SPR values for configurable control/performance
344 * registers, and use those as initial defaults.
346 record_spr_defaults();
349 * At this point, we can let interrupts switch to virtual mode
350 * (the MMU has been setup), so adjust the MSR in the PACA to
351 * have IR and DR set and enable AIL if it exists
353 cpu_ready_for_interrupts();
356 * We enable ftrace here, but since we only support DYNAMIC_FTRACE, it
357 * will only actually get enabled on the boot cpu much later once
358 * ftrace itself has been initialized.
360 this_cpu_enable_ftrace();
362 udbg_printf(" <- %s()\n", __func__);
364 #ifdef CONFIG_PPC_EARLY_DEBUG_BOOTX
366 * This needs to be done *last* (after the above udbg_printf() even)
368 * Right after we return from this function, we turn on the MMU
369 * which means the real-mode access trick that btext does will
370 * no longer work, it needs to switch to using a real MMU
371 * mapping. This call will ensure that it does
373 btext_map();
374 #endif /* CONFIG_PPC_EARLY_DEBUG_BOOTX */
377 #ifdef CONFIG_SMP
378 void early_setup_secondary(void)
380 /* Mark interrupts disabled in PACA */
381 irq_soft_mask_set(IRQS_DISABLED);
383 /* Initialize the hash table or TLB handling */
384 early_init_mmu_secondary();
386 /* Perform any KUP setup that is per-cpu */
387 setup_kup();
390 * At this point, we can let interrupts switch to virtual mode
391 * (the MMU has been setup), so adjust the MSR in the PACA to
392 * have IR and DR set.
394 cpu_ready_for_interrupts();
397 #endif /* CONFIG_SMP */
399 void panic_smp_self_stop(void)
401 hard_irq_disable();
402 spin_begin();
403 while (1)
404 spin_cpu_relax();
407 #if defined(CONFIG_SMP) || defined(CONFIG_KEXEC_CORE)
408 static bool use_spinloop(void)
410 if (IS_ENABLED(CONFIG_PPC_BOOK3S)) {
412 * See comments in head_64.S -- not all platforms insert
413 * secondaries at __secondary_hold and wait at the spin
414 * loop.
416 if (firmware_has_feature(FW_FEATURE_OPAL))
417 return false;
418 return true;
422 * When book3e boots from kexec, the ePAPR spin table does
423 * not get used.
425 return of_property_read_bool(of_chosen, "linux,booted-from-kexec");
428 void smp_release_cpus(void)
430 unsigned long *ptr;
431 int i;
433 if (!use_spinloop())
434 return;
436 /* All secondary cpus are spinning on a common spinloop, release them
437 * all now so they can start to spin on their individual paca
438 * spinloops. For non SMP kernels, the secondary cpus never get out
439 * of the common spinloop.
442 ptr = (unsigned long *)((unsigned long)&__secondary_hold_spinloop
443 - PHYSICAL_START);
444 *ptr = ppc_function_entry(generic_secondary_smp_init);
446 /* And wait a bit for them to catch up */
447 for (i = 0; i < 100000; i++) {
448 mb();
449 HMT_low();
450 if (spinning_secondaries == 0)
451 break;
452 udelay(1);
454 pr_debug("spinning_secondaries = %d\n", spinning_secondaries);
456 #endif /* CONFIG_SMP || CONFIG_KEXEC_CORE */
459 * Initialize some remaining members of the ppc64_caches and systemcfg
460 * structures
461 * (at least until we get rid of them completely). This is mostly some
462 * cache informations about the CPU that will be used by cache flush
463 * routines and/or provided to userland
466 static void init_cache_info(struct ppc_cache_info *info, u32 size, u32 lsize,
467 u32 bsize, u32 sets)
469 info->size = size;
470 info->sets = sets;
471 info->line_size = lsize;
472 info->block_size = bsize;
473 info->log_block_size = __ilog2(bsize);
474 if (bsize)
475 info->blocks_per_page = PAGE_SIZE / bsize;
476 else
477 info->blocks_per_page = 0;
479 if (sets == 0)
480 info->assoc = 0xffff;
481 else
482 info->assoc = size / (sets * lsize);
485 static bool __init parse_cache_info(struct device_node *np,
486 bool icache,
487 struct ppc_cache_info *info)
489 static const char *ipropnames[] __initdata = {
490 "i-cache-size",
491 "i-cache-sets",
492 "i-cache-block-size",
493 "i-cache-line-size",
495 static const char *dpropnames[] __initdata = {
496 "d-cache-size",
497 "d-cache-sets",
498 "d-cache-block-size",
499 "d-cache-line-size",
501 const char **propnames = icache ? ipropnames : dpropnames;
502 const __be32 *sizep, *lsizep, *bsizep, *setsp;
503 u32 size, lsize, bsize, sets;
504 bool success = true;
506 size = 0;
507 sets = -1u;
508 lsize = bsize = cur_cpu_spec->dcache_bsize;
509 sizep = of_get_property(np, propnames[0], NULL);
510 if (sizep != NULL)
511 size = be32_to_cpu(*sizep);
512 setsp = of_get_property(np, propnames[1], NULL);
513 if (setsp != NULL)
514 sets = be32_to_cpu(*setsp);
515 bsizep = of_get_property(np, propnames[2], NULL);
516 lsizep = of_get_property(np, propnames[3], NULL);
517 if (bsizep == NULL)
518 bsizep = lsizep;
519 if (lsizep != NULL)
520 lsize = be32_to_cpu(*lsizep);
521 if (bsizep != NULL)
522 bsize = be32_to_cpu(*bsizep);
523 if (sizep == NULL || bsizep == NULL || lsizep == NULL)
524 success = false;
527 * OF is weird .. it represents fully associative caches
528 * as "1 way" which doesn't make much sense and doesn't
529 * leave room for direct mapped. We'll assume that 0
530 * in OF means direct mapped for that reason.
532 if (sets == 1)
533 sets = 0;
534 else if (sets == 0)
535 sets = 1;
537 init_cache_info(info, size, lsize, bsize, sets);
539 return success;
542 void __init initialize_cache_info(void)
544 struct device_node *cpu = NULL, *l2, *l3 = NULL;
545 u32 pvr;
548 * All shipping POWER8 machines have a firmware bug that
549 * puts incorrect information in the device-tree. This will
550 * be (hopefully) fixed for future chips but for now hard
551 * code the values if we are running on one of these
553 pvr = PVR_VER(mfspr(SPRN_PVR));
554 if (pvr == PVR_POWER8 || pvr == PVR_POWER8E ||
555 pvr == PVR_POWER8NVL) {
556 /* size lsize blk sets */
557 init_cache_info(&ppc64_caches.l1i, 0x8000, 128, 128, 32);
558 init_cache_info(&ppc64_caches.l1d, 0x10000, 128, 128, 64);
559 init_cache_info(&ppc64_caches.l2, 0x80000, 128, 0, 512);
560 init_cache_info(&ppc64_caches.l3, 0x800000, 128, 0, 8192);
561 } else
562 cpu = of_find_node_by_type(NULL, "cpu");
565 * We're assuming *all* of the CPUs have the same
566 * d-cache and i-cache sizes... -Peter
568 if (cpu) {
569 if (!parse_cache_info(cpu, false, &ppc64_caches.l1d))
570 pr_warn("Argh, can't find dcache properties !\n");
572 if (!parse_cache_info(cpu, true, &ppc64_caches.l1i))
573 pr_warn("Argh, can't find icache properties !\n");
576 * Try to find the L2 and L3 if any. Assume they are
577 * unified and use the D-side properties.
579 l2 = of_find_next_cache_node(cpu);
580 of_node_put(cpu);
581 if (l2) {
582 parse_cache_info(l2, false, &ppc64_caches.l2);
583 l3 = of_find_next_cache_node(l2);
584 of_node_put(l2);
586 if (l3) {
587 parse_cache_info(l3, false, &ppc64_caches.l3);
588 of_node_put(l3);
592 /* For use by binfmt_elf */
593 dcache_bsize = ppc64_caches.l1d.block_size;
594 icache_bsize = ppc64_caches.l1i.block_size;
596 cur_cpu_spec->dcache_bsize = dcache_bsize;
597 cur_cpu_spec->icache_bsize = icache_bsize;
601 * This returns the limit below which memory accesses to the linear
602 * mapping are guarnateed not to cause an architectural exception (e.g.,
603 * TLB or SLB miss fault).
605 * This is used to allocate PACAs and various interrupt stacks that
606 * that are accessed early in interrupt handlers that must not cause
607 * re-entrant interrupts.
609 __init u64 ppc64_bolted_size(void)
611 #ifdef CONFIG_PPC_BOOK3E
612 /* Freescale BookE bolts the entire linear mapping */
613 /* XXX: BookE ppc64_rma_limit setup seems to disagree? */
614 if (early_mmu_has_feature(MMU_FTR_TYPE_FSL_E))
615 return linear_map_top;
616 /* Other BookE, we assume the first GB is bolted */
617 return 1ul << 30;
618 #else
619 /* BookS radix, does not take faults on linear mapping */
620 if (early_radix_enabled())
621 return ULONG_MAX;
623 /* BookS hash, the first segment is bolted */
624 if (early_mmu_has_feature(MMU_FTR_1T_SEGMENT))
625 return 1UL << SID_SHIFT_1T;
626 return 1UL << SID_SHIFT;
627 #endif
630 static void *__init alloc_stack(unsigned long limit, int cpu)
632 void *ptr;
634 BUILD_BUG_ON(STACK_INT_FRAME_SIZE % 16);
636 ptr = memblock_alloc_try_nid(THREAD_SIZE, THREAD_ALIGN,
637 MEMBLOCK_LOW_LIMIT, limit,
638 early_cpu_to_node(cpu));
639 if (!ptr)
640 panic("cannot allocate stacks");
642 return ptr;
645 void __init irqstack_early_init(void)
647 u64 limit = ppc64_bolted_size();
648 unsigned int i;
651 * Interrupt stacks must be in the first segment since we
652 * cannot afford to take SLB misses on them. They are not
653 * accessed in realmode.
655 for_each_possible_cpu(i) {
656 softirq_ctx[i] = alloc_stack(limit, i);
657 hardirq_ctx[i] = alloc_stack(limit, i);
661 #ifdef CONFIG_PPC_BOOK3E
662 void __init exc_lvl_early_init(void)
664 unsigned int i;
666 for_each_possible_cpu(i) {
667 void *sp;
669 sp = alloc_stack(ULONG_MAX, i);
670 critirq_ctx[i] = sp;
671 paca_ptrs[i]->crit_kstack = sp + THREAD_SIZE;
673 sp = alloc_stack(ULONG_MAX, i);
674 dbgirq_ctx[i] = sp;
675 paca_ptrs[i]->dbg_kstack = sp + THREAD_SIZE;
677 sp = alloc_stack(ULONG_MAX, i);
678 mcheckirq_ctx[i] = sp;
679 paca_ptrs[i]->mc_kstack = sp + THREAD_SIZE;
682 if (cpu_has_feature(CPU_FTR_DEBUG_LVL_EXC))
683 patch_exception(0x040, exc_debug_debug_book3e);
685 #endif
688 * Stack space used when we detect a bad kernel stack pointer, and
689 * early in SMP boots before relocation is enabled. Exclusive emergency
690 * stack for machine checks.
692 void __init emergency_stack_init(void)
694 u64 limit;
695 unsigned int i;
698 * Emergency stacks must be under 256MB, we cannot afford to take
699 * SLB misses on them. The ABI also requires them to be 128-byte
700 * aligned.
702 * Since we use these as temporary stacks during secondary CPU
703 * bringup, machine check, system reset, and HMI, we need to get
704 * at them in real mode. This means they must also be within the RMO
705 * region.
707 * The IRQ stacks allocated elsewhere in this file are zeroed and
708 * initialized in kernel/irq.c. These are initialized here in order
709 * to have emergency stacks available as early as possible.
711 limit = min(ppc64_bolted_size(), ppc64_rma_size);
713 for_each_possible_cpu(i) {
714 paca_ptrs[i]->emergency_sp = alloc_stack(limit, i) + THREAD_SIZE;
716 #ifdef CONFIG_PPC_BOOK3S_64
717 /* emergency stack for NMI exception handling. */
718 paca_ptrs[i]->nmi_emergency_sp = alloc_stack(limit, i) + THREAD_SIZE;
720 /* emergency stack for machine check exception handling. */
721 paca_ptrs[i]->mc_emergency_sp = alloc_stack(limit, i) + THREAD_SIZE;
722 #endif
726 #ifdef CONFIG_SMP
727 #define PCPU_DYN_SIZE ()
729 static void * __init pcpu_fc_alloc(unsigned int cpu, size_t size, size_t align)
731 return memblock_alloc_try_nid(size, align, __pa(MAX_DMA_ADDRESS),
732 MEMBLOCK_ALLOC_ACCESSIBLE,
733 early_cpu_to_node(cpu));
737 static void __init pcpu_fc_free(void *ptr, size_t size)
739 memblock_free(__pa(ptr), size);
742 static int pcpu_cpu_distance(unsigned int from, unsigned int to)
744 if (early_cpu_to_node(from) == early_cpu_to_node(to))
745 return LOCAL_DISTANCE;
746 else
747 return REMOTE_DISTANCE;
750 unsigned long __per_cpu_offset[NR_CPUS] __read_mostly;
751 EXPORT_SYMBOL(__per_cpu_offset);
753 void __init setup_per_cpu_areas(void)
755 const size_t dyn_size = PERCPU_MODULE_RESERVE + PERCPU_DYNAMIC_RESERVE;
756 size_t atom_size;
757 unsigned long delta;
758 unsigned int cpu;
759 int rc;
762 * Linear mapping is one of 4K, 1M and 16M. For 4K, no need
763 * to group units. For larger mappings, use 1M atom which
764 * should be large enough to contain a number of units.
766 if (mmu_linear_psize == MMU_PAGE_4K)
767 atom_size = PAGE_SIZE;
768 else
769 atom_size = 1 << 20;
771 rc = pcpu_embed_first_chunk(0, dyn_size, atom_size, pcpu_cpu_distance,
772 pcpu_fc_alloc, pcpu_fc_free);
773 if (rc < 0)
774 panic("cannot initialize percpu area (err=%d)", rc);
776 delta = (unsigned long)pcpu_base_addr - (unsigned long)__per_cpu_start;
777 for_each_possible_cpu(cpu) {
778 __per_cpu_offset[cpu] = delta + pcpu_unit_offsets[cpu];
779 paca_ptrs[cpu]->data_offset = __per_cpu_offset[cpu];
782 #endif
784 #ifdef CONFIG_MEMORY_HOTPLUG_SPARSE
785 unsigned long memory_block_size_bytes(void)
787 if (ppc_md.memory_block_size)
788 return ppc_md.memory_block_size();
790 return MIN_MEMORY_BLOCK_SIZE;
792 #endif
794 #if defined(CONFIG_PPC_INDIRECT_PIO) || defined(CONFIG_PPC_INDIRECT_MMIO)
795 struct ppc_pci_io ppc_pci_io;
796 EXPORT_SYMBOL(ppc_pci_io);
797 #endif
799 #ifdef CONFIG_HARDLOCKUP_DETECTOR_PERF
800 u64 hw_nmi_get_sample_period(int watchdog_thresh)
802 return ppc_proc_freq * watchdog_thresh;
804 #endif
807 * The perf based hardlockup detector breaks PMU event based branches, so
808 * disable it by default. Book3S has a soft-nmi hardlockup detector based
809 * on the decrementer interrupt, so it does not suffer from this problem.
811 * It is likely to get false positives in VM guests, so disable it there
812 * by default too.
814 static int __init disable_hardlockup_detector(void)
816 #ifdef CONFIG_HARDLOCKUP_DETECTOR_PERF
817 hardlockup_detector_disable();
818 #else
819 if (firmware_has_feature(FW_FEATURE_LPAR))
820 hardlockup_detector_disable();
821 #endif
823 return 0;
825 early_initcall(disable_hardlockup_detector);
827 #ifdef CONFIG_PPC_BOOK3S_64
828 static enum l1d_flush_type enabled_flush_types;
829 static void *l1d_flush_fallback_area;
830 static bool no_rfi_flush;
831 bool rfi_flush;
833 static int __init handle_no_rfi_flush(char *p)
835 pr_info("rfi-flush: disabled on command line.");
836 no_rfi_flush = true;
837 return 0;
839 early_param("no_rfi_flush", handle_no_rfi_flush);
842 * The RFI flush is not KPTI, but because users will see doco that says to use
843 * nopti we hijack that option here to also disable the RFI flush.
845 static int __init handle_no_pti(char *p)
847 pr_info("rfi-flush: disabling due to 'nopti' on command line.\n");
848 handle_no_rfi_flush(NULL);
849 return 0;
851 early_param("nopti", handle_no_pti);
853 static void do_nothing(void *unused)
856 * We don't need to do the flush explicitly, just enter+exit kernel is
857 * sufficient, the RFI exit handlers will do the right thing.
861 void rfi_flush_enable(bool enable)
863 if (enable) {
864 do_rfi_flush_fixups(enabled_flush_types);
865 on_each_cpu(do_nothing, NULL, 1);
866 } else
867 do_rfi_flush_fixups(L1D_FLUSH_NONE);
869 rfi_flush = enable;
872 static void __ref init_fallback_flush(void)
874 u64 l1d_size, limit;
875 int cpu;
877 /* Only allocate the fallback flush area once (at boot time). */
878 if (l1d_flush_fallback_area)
879 return;
881 l1d_size = ppc64_caches.l1d.size;
884 * If there is no d-cache-size property in the device tree, l1d_size
885 * could be zero. That leads to the loop in the asm wrapping around to
886 * 2^64-1, and then walking off the end of the fallback area and
887 * eventually causing a page fault which is fatal. Just default to
888 * something vaguely sane.
890 if (!l1d_size)
891 l1d_size = (64 * 1024);
893 limit = min(ppc64_bolted_size(), ppc64_rma_size);
896 * Align to L1d size, and size it at 2x L1d size, to catch possible
897 * hardware prefetch runoff. We don't have a recipe for load patterns to
898 * reliably avoid the prefetcher.
900 l1d_flush_fallback_area = memblock_alloc_try_nid(l1d_size * 2,
901 l1d_size, MEMBLOCK_LOW_LIMIT,
902 limit, NUMA_NO_NODE);
903 if (!l1d_flush_fallback_area)
904 panic("%s: Failed to allocate %llu bytes align=0x%llx max_addr=%pa\n",
905 __func__, l1d_size * 2, l1d_size, &limit);
908 for_each_possible_cpu(cpu) {
909 struct paca_struct *paca = paca_ptrs[cpu];
910 paca->rfi_flush_fallback_area = l1d_flush_fallback_area;
911 paca->l1d_flush_size = l1d_size;
915 void setup_rfi_flush(enum l1d_flush_type types, bool enable)
917 if (types & L1D_FLUSH_FALLBACK) {
918 pr_info("rfi-flush: fallback displacement flush available\n");
919 init_fallback_flush();
922 if (types & L1D_FLUSH_ORI)
923 pr_info("rfi-flush: ori type flush available\n");
925 if (types & L1D_FLUSH_MTTRIG)
926 pr_info("rfi-flush: mttrig type flush available\n");
928 enabled_flush_types = types;
930 if (!no_rfi_flush && !cpu_mitigations_off())
931 rfi_flush_enable(enable);
934 #ifdef CONFIG_DEBUG_FS
935 static int rfi_flush_set(void *data, u64 val)
937 bool enable;
939 if (val == 1)
940 enable = true;
941 else if (val == 0)
942 enable = false;
943 else
944 return -EINVAL;
946 /* Only do anything if we're changing state */
947 if (enable != rfi_flush)
948 rfi_flush_enable(enable);
950 return 0;
953 static int rfi_flush_get(void *data, u64 *val)
955 *val = rfi_flush ? 1 : 0;
956 return 0;
959 DEFINE_SIMPLE_ATTRIBUTE(fops_rfi_flush, rfi_flush_get, rfi_flush_set, "%llu\n");
961 static __init int rfi_flush_debugfs_init(void)
963 debugfs_create_file("rfi_flush", 0600, powerpc_debugfs_root, NULL, &fops_rfi_flush);
964 return 0;
966 device_initcall(rfi_flush_debugfs_init);
967 #endif
968 #endif /* CONFIG_PPC_BOOK3S_64 */