/*
*
* 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 <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/hugetlb.h>
#include <linux/memory.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/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/mmu_context.h>
#include <asm/code-patching.h>
#include <asm/kvm_ppc.h>
#include <asm/hugetlb.h>
#include <asm/epapr_hcalls.h>
#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)
static void 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);
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__);
}
}
}
#else
static void setup_tlb_core_data(void)
{
}
#endif
#ifdef CONFIG_SMP
static char *smt_enabled_cmdline;
/* Look for ibm,smt-enabled OF option */
static void 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);
#else
#define check_smt_enabled()
#endif /* CONFIG_SMP */
/** Fix up paca fields required for the boot cpu */
static void 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 cpu_ready_for_interrupts(void)
{
/* Set IR and DR in PACA MSR */
get_paca()->kernel_msr = MSR_KERNEL;
/*
* Enable AIL if supported, and we are in hypervisor mode. If we are
* not in hypervisor mode, we enable relocation-on interrupts later
* in pSeries_setup_arch() using the H_SET_MODE hcall.
*/
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);
}
}
/*
* 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();
/* Initialize lockdep early or else spinlocks will blow */
lockdep_init();
/* -------- 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));
epapr_paravirt_early_init();
/* Now we know the logical id of our boot cpu, setup the paca. */
setup_paca(&paca[boot_cpuid]);
fixup_boot_paca();
/* Probe the machine type */
probe_machine();
setup_kdump_trampoline();
DBG("Found, Initializing memory management...\n");
/* 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();
/* Reserve large chunks of memory for use by CMA for KVM */
kvm_cma_reserve();
/*
* Reserve any gigantic pages requested on the command line.
* memblock needs to have been initialized by the time this is
* called since this will reserve memory.
*/
reserve_hugetlb_gpages();
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 enabled 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)
void smp_release_cpus(void)
{
unsigned long *ptr;
int i;
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
*/
static 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;
}
}
DBG(" <- initialize_cache_info()\n");
}
/*
* Do some initial setup of the system. The parameters are those which
* were passed in from the bootloader.
*/
void __init setup_system(void)
{
DBG(" -> setup_system()\n");
/* Apply the CPUs-specific and firmware specific fixups to kernel
* text (nop out sections not relevant to this CPU or this firmware)
*/
do_feature_fixups(cur_cpu_spec->cpu_features,
&__start___ftr_fixup, &__stop___ftr_fixup);
do_feature_fixups(cur_cpu_spec->mmu_features,
&__start___mmu_ftr_fixup, &__stop___mmu_ftr_fixup);
do_feature_fixups(powerpc_firmware_features,
&__start___fw_ftr_fixup, &__stop___fw_ftr_fixup);
do_lwsync_fixups(cur_cpu_spec->cpu_features,
&__start___lwsync_fixup, &__stop___lwsync_fixup);
do_final_fixups();
/*
* Unflatten the device-tree passed by prom_init or kexec
*/
unflatten_device_tree();
/*
* Fill the ppc64_caches & systemcfg structures with informations
* retrieved from the device-tree.
*/
initialize_cache_info();
#ifdef CONFIG_PPC_RTAS
/*
* Initialize RTAS if available
*/
rtas_initialize();
#endif /* CONFIG_PPC_RTAS */
/*
* Check if we have an initrd provided via the device-tree
*/
check_for_initrd();
/*
* Do some platform specific early initializations, that includes
* setting up the hash table pointers. It also sets up some interrupt-mapping
* related options that will be used by finish_device_tree()
*/
if (ppc_md.init_early)
ppc_md.init_early();
/*
* We can discover serial ports now since the above did setup the
* hash table management for us, thus ioremap works. We do that early
* so that further code can be debugged
*/
find_legacy_serial_ports();
/*
* Register early console
*/
register_early_udbg_console();
/*
* Initialize xmon
*/
xmon_setup();
smp_setup_cpu_maps();
check_smt_enabled();
setup_tlb_core_data();
/*
* Freescale Book3e parts spin in a loop provided by firmware,
* so smp_release_cpus() does nothing for them
*/
#if defined(CONFIG_SMP) && !defined(CONFIG_PPC_FSL_BOOK3E)
/* Release secondary cpus out of their spinloops at 0x60 now that
* we can map physical -> logical CPU ids
*/
smp_release_cpus();
#endif
pr_info("Starting Linux PPC64 %s\n", init_utsname()->version);
pr_info("-----------------------------------------------------\n");
pr_info("ppc64_pft_size = 0x%llx\n", ppc64_pft_size);
pr_info("phys_mem_size = 0x%llx\n", memblock_phys_mem_size());
if (ppc64_caches.dline_size != 0x80)
pr_info("dcache_line_size = 0x%x\n", ppc64_caches.dline_size);
if (ppc64_caches.iline_size != 0x80)
pr_info("icache_line_size = 0x%x\n", ppc64_caches.iline_size);
pr_info("cpu_features = 0x%016lx\n", cur_cpu_spec->cpu_features);
pr_info(" possible = 0x%016lx\n", CPU_FTRS_POSSIBLE);
pr_info(" always = 0x%016lx\n", 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);
pr_info("firmware_features = 0x%016lx\n", powerpc_firmware_features);
#ifdef CONFIG_PPC_STD_MMU_64
if (htab_address)
pr_info("htab_address = 0x%p\n", htab_address);
pr_info("htab_hash_mask = 0x%lx\n", htab_hash_mask);
#endif
if (PHYSICAL_START > 0)
pr_info("physical_start = 0x%llx\n",
(unsigned long long)PHYSICAL_START);
pr_info("-----------------------------------------------------\n");
DBG(" <- setup_system()\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 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
}
static 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
static 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);
}
#else
#define exc_lvl_early_init()
#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.
*/
static 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) {
unsigned long sp;
sp = memblock_alloc_base(THREAD_SIZE, THREAD_SIZE, limit);
sp += THREAD_SIZE;
paca[i].emergency_sp = __va(sp);
#ifdef CONFIG_PPC_BOOK3S_64
/* emergency stack for machine check exception handling. */
sp = memblock_alloc_base(THREAD_SIZE, THREAD_SIZE, limit);
sp += THREAD_SIZE;
paca[i].mc_emergency_sp = __va(sp);
#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)
{
*cmdline_p = boot_command_line;
/*
* Set cache line size based on type of cpu as a default.
* Systems with OF can look in the properties on the cpu node(s)
* for a possibly more accurate value.
*/
dcache_bsize = ppc64_caches.dline_size;
icache_bsize = ppc64_caches.iline_size;
if (ppc_md.panic)
setup_panic();
init_mm.start_code = (unsigned long)_stext;
init_mm.end_code = (unsigned long) _etext;
init_mm.end_data = (unsigned long) _edata;
init_mm.brk = klimit;
#ifdef CONFIG_PPC_64K_PAGES
init_mm.context.pte_frag = NULL;
#endif
irqstack_early_init();
exc_lvl_early_init();
emergency_stack_init();
initmem_init();
#ifdef CONFIG_DUMMY_CONSOLE
conswitchp = &dummy_con;
#endif
if (ppc_md.setup_arch)
ppc_md.setup_arch();
paging_init();
/* Initialize the MMU context management stuff */
mmu_context_init();
/* Interrupt code needs to be 64K-aligned */
if ((unsigned long)_stext & 0xffff)
panic("Kernelbase not 64K-aligned (0x%lx)!\n",
(unsigned long)_stext);
}
#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
