kernel-fxtec-pro1x/arch/powerpc/kernel/setup_64.c
Anton Blanchard 7a0268fa1a [PATCH] powerpc/64: per cpu data optimisations
The current ppc64 per cpu data implementation is quite slow. eg:

        lhz 11,18(13)           /* smp_processor_id() */
        ld 9,.LC63-.LCTOC1(30)  /* per_cpu__variable_name */
        ld 8,.LC61-.LCTOC1(30)  /* __per_cpu_offset */
        sldi 11,11,3            /* form index into __per_cpu_offset */
        mr 10,9
        ldx 9,11,8              /* __per_cpu_offset[smp_processor_id()] */
        ldx 0,10,9              /* load per cpu data */

5 loads for something that is supposed to be fast, pretty awful. One
reason for the large number of loads is that we have to synthesize 2
64bit constants (per_cpu__variable_name and __per_cpu_offset).

By putting __per_cpu_offset into the paca we can avoid the 2 loads
associated with it:

        ld 11,56(13)            /* paca->data_offset */
        ld 9,.LC59-.LCTOC1(30)  /* per_cpu__variable_name */
        ldx 0,9,11              /* load per cpu data

Longer term we can should be able to do even better than 3 loads.
If per_cpu__variable_name wasnt a 64bit constant and paca->data_offset
was in a register we could cut it down to one load. A suggestion from
Rusty is to use gcc's __thread extension here. In order to do this we
would need to free up r13 (the __thread register and where the paca
currently is). So far Ive had a few unsuccessful attempts at doing that :)

The patch also allocates per cpu memory node local on NUMA machines.
This patch from Rusty has been sitting in my queue _forever_ but stalled
when I hit the compiler bug. Sorry about that.

Finally I also only allocate per cpu data for possible cpus, which comes
straight out of the x86-64 port. On a pseries kernel (with NR_CPUS == 128)
and 4 possible cpus we see some nice gains:

             total       used       free     shared    buffers cached
Mem:       4012228     212860    3799368          0          0 162424

             total       used       free     shared    buffers cached
Mem:       4016200     212984    3803216          0          0 162424

A saving of 3.75MB. Quite nice for smaller machines. Note: we now have
to be careful of per cpu users that touch data for !possible cpus.

At this stage it might be worth making the NUMA and possible cpu
optimisations generic, but per cpu init is done so early we have to be
careful that all architectures have their possible map setup correctly.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-01-11 14:49:45 +11:00

682 lines
17 KiB
C

/*
*
* 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.
*/
#undef DEBUG
#include <linux/config.h>
#include <linux/module.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/ide.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 <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/system.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/lmb.h>
#include <asm/iseries/it_lp_naca.h>
#include <asm/firmware.h>
#include <asm/xmon.h>
#include <asm/udbg.h>
#include <asm/kexec.h>
#include "setup.h"
#ifdef DEBUG
#define DBG(fmt...) udbg_printf(fmt)
#else
#define DBG(fmt...)
#endif
int have_of = 1;
int boot_cpuid = 0;
int boot_cpuid_phys = 0;
dev_t boot_dev;
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 = 0x80,
.log_dline_size = 7,
.iline_size = 0x80,
.log_iline_size = 7
};
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;
/* The main machine-dep calls structure
*/
struct machdep_calls ppc_md;
EXPORT_SYMBOL(ppc_md);
#ifdef CONFIG_MAGIC_SYSRQ
unsigned long SYSRQ_KEY;
#endif /* CONFIG_MAGIC_SYSRQ */
static int ppc64_panic_event(struct notifier_block *, unsigned long, void *);
static struct notifier_block ppc64_panic_block = {
.notifier_call = ppc64_panic_event,
.priority = INT_MIN /* may not return; must be done last */
};
#ifdef CONFIG_SMP
static int smt_enabled_cmdline;
/* Look for ibm,smt-enabled OF option */
static void check_smt_enabled(void)
{
struct device_node *dn;
char *smt_option;
/* Allow the command line to overrule the OF option */
if (smt_enabled_cmdline)
return;
dn = of_find_node_by_path("/options");
if (dn) {
smt_option = (char *)get_property(dn, "ibm,smt-enabled", NULL);
if (smt_option) {
if (!strcmp(smt_option, "on"))
smt_enabled_at_boot = 1;
else if (!strcmp(smt_option, "off"))
smt_enabled_at_boot = 0;
}
}
}
/* Look for smt-enabled= cmdline option */
static int __init early_smt_enabled(char *p)
{
smt_enabled_cmdline = 1;
if (!p)
return 0;
if (!strcmp(p, "on") || !strcmp(p, "1"))
smt_enabled_at_boot = 1;
else if (!strcmp(p, "off") || !strcmp(p, "0"))
smt_enabled_at_boot = 0;
return 0;
}
early_param("smt-enabled", early_smt_enabled);
#else
#define check_smt_enabled()
#endif /* CONFIG_SMP */
extern struct machdep_calls pSeries_md;
extern struct machdep_calls pmac_md;
extern struct machdep_calls maple_md;
extern struct machdep_calls cell_md;
extern struct machdep_calls iseries_md;
/* Ultimately, stuff them in an elf section like initcalls... */
static struct machdep_calls __initdata *machines[] = {
#ifdef CONFIG_PPC_PSERIES
&pSeries_md,
#endif /* CONFIG_PPC_PSERIES */
#ifdef CONFIG_PPC_PMAC
&pmac_md,
#endif /* CONFIG_PPC_PMAC */
#ifdef CONFIG_PPC_MAPLE
&maple_md,
#endif /* CONFIG_PPC_MAPLE */
#ifdef CONFIG_PPC_CELL
&cell_md,
#endif
#ifdef CONFIG_PPC_ISERIES
&iseries_md,
#endif
NULL
};
/*
* 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 LMB
* 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)
{
struct paca_struct *lpaca = get_paca();
static struct machdep_calls **mach;
/* Enable early debugging if any specified (see udbg.h) */
udbg_early_init();
DBG(" -> early_setup()\n");
/*
* Do early initializations using the flattened device
* tree, like retreiving the physical memory map or
* calculating/retreiving the hash table size
*/
early_init_devtree(__va(dt_ptr));
/*
* Iterate all ppc_md structures until we find the proper
* one for the current machine type
*/
DBG("Probing machine type for platform %x...\n", _machine);
for (mach = machines; *mach; mach++) {
if ((*mach)->probe(_machine))
break;
}
/* What can we do if we didn't find ? */
if (*mach == NULL) {
DBG("No suitable machine found !\n");
for (;;);
}
ppc_md = **mach;
#ifdef CONFIG_CRASH_DUMP
kdump_setup();
#endif
DBG("Found, Initializing memory management...\n");
/*
* Initialize the MMU Hash table and create the linear mapping
* of memory. Has to be done before stab/slb initialization as
* this is currently where the page size encoding is obtained
*/
htab_initialize();
/*
* Initialize stab / SLB management except on iSeries
*/
if (!firmware_has_feature(FW_FEATURE_ISERIES)) {
if (cpu_has_feature(CPU_FTR_SLB))
slb_initialize();
else
stab_initialize(lpaca->stab_real);
}
DBG(" <- early_setup()\n");
}
#ifdef CONFIG_SMP
void early_setup_secondary(void)
{
struct paca_struct *lpaca = get_paca();
/* Mark enabled in PACA */
lpaca->proc_enabled = 0;
/* Initialize hash table for that CPU */
htab_initialize_secondary();
/* Initialize STAB/SLB. We use a virtual address as it works
* in real mode on pSeries and we want a virutal address on
* iSeries anyway
*/
if (cpu_has_feature(CPU_FTR_SLB))
slb_initialize();
else
stab_initialize(lpaca->stab_addr);
}
#endif /* CONFIG_SMP */
#if defined(CONFIG_SMP) || defined(CONFIG_KEXEC)
void smp_release_cpus(void)
{
extern unsigned long __secondary_hold_spinloop;
unsigned long *ptr;
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.
* This is useless but harmless on iSeries, secondaries are already
* waiting on their paca spinloops. */
ptr = (unsigned long *)((unsigned long)&__secondary_hold_spinloop
- PHYSICAL_START);
*ptr = 1;
mb();
DBG(" <- smp_release_cpus()\n");
}
#else
#define smp_release_cpus()
#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 (np = NULL; (np = of_find_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 ) {
u32 *sizep, *lsizep;
u32 size, lsize;
const char *dc, *ic;
/* Then read cache informations */
if (_machine == PLATFORM_POWERMAC) {
dc = "d-cache-block-size";
ic = "i-cache-block-size";
} else {
dc = "d-cache-line-size";
ic = "i-cache-line-size";
}
size = 0;
lsize = cur_cpu_spec->dcache_bsize;
sizep = (u32 *)get_property(np, "d-cache-size", NULL);
if (sizep != NULL)
size = *sizep;
lsizep = (u32 *) get_property(np, dc, NULL);
if (lsizep != NULL)
lsize = *lsizep;
if (sizep == 0 || lsizep == 0)
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 = (u32 *)get_property(np, "i-cache-size", NULL);
if (sizep != NULL)
size = *sizep;
lsizep = (u32 *)get_property(np, ic, NULL);
if (lsizep != NULL)
lsize = *lsizep;
if (sizep == 0 || lsizep == 0)
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");
/*
* Unflatten the device-tree passed by prom_init or kexec
*/
unflatten_device_tree();
#ifdef CONFIG_KEXEC
kexec_setup(); /* requires unflattened device tree. */
#endif
/*
* Fill the ppc64_caches & systemcfg structures with informations
* retrieved from the device-tree. Need to be called before
* finish_device_tree() since the later requires some of the
* informations filled up here to properly parse the interrupt
* tree.
* It also sets up the cache line sizes which allows to call
* routines like flush_icache_range (used by the hash init
* later on).
*/
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()
*/
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();
/*
* "Finish" the device-tree, that is do the actual parsing of
* some of the properties like the interrupt map
*/
finish_device_tree();
/*
* Initialize xmon
*/
#ifdef CONFIG_XMON_DEFAULT
xmon_init(1);
#endif
/*
* Register early console
*/
register_early_udbg_console();
/* Save unparsed command line copy for /proc/cmdline */
strlcpy(saved_command_line, cmd_line, COMMAND_LINE_SIZE);
parse_early_param();
check_smt_enabled();
smp_setup_cpu_maps();
/* Release secondary cpus out of their spinloops at 0x60 now that
* we can map physical -> logical CPU ids
*/
smp_release_cpus();
printk("Starting Linux PPC64 %s\n", system_utsname.version);
printk("-----------------------------------------------------\n");
printk("ppc64_pft_size = 0x%lx\n", ppc64_pft_size);
printk("ppc64_interrupt_controller = 0x%ld\n",
ppc64_interrupt_controller);
printk("platform = 0x%x\n", _machine);
printk("physicalMemorySize = 0x%lx\n", lmb_phys_mem_size());
printk("ppc64_caches.dcache_line_size = 0x%x\n",
ppc64_caches.dline_size);
printk("ppc64_caches.icache_line_size = 0x%x\n",
ppc64_caches.iline_size);
printk("htab_address = 0x%p\n", htab_address);
printk("htab_hash_mask = 0x%lx\n", htab_hash_mask);
#if PHYSICAL_START > 0
printk("physical_start = 0x%x\n", PHYSICAL_START);
#endif
printk("-----------------------------------------------------\n");
mm_init_ppc64();
DBG(" <- setup_system()\n");
}
static int ppc64_panic_event(struct notifier_block *this,
unsigned long event, void *ptr)
{
ppc_md.panic((char *)ptr); /* May not return */
return NOTIFY_DONE;
}
#ifdef CONFIG_IRQSTACKS
static void __init irqstack_early_init(void)
{
unsigned int i;
/*
* interrupt stacks must be under 256MB, we cannot afford to take
* SLB misses on them.
*/
for_each_cpu(i) {
softirq_ctx[i] = (struct thread_info *)
__va(lmb_alloc_base(THREAD_SIZE,
THREAD_SIZE, 0x10000000));
hardirq_ctx[i] = (struct thread_info *)
__va(lmb_alloc_base(THREAD_SIZE,
THREAD_SIZE, 0x10000000));
}
}
#else
#define irqstack_early_init()
#endif
/*
* Stack space used when we detect a bad kernel stack pointer, and
* early in SMP boots before relocation is enabled.
*/
static void __init emergency_stack_init(void)
{
unsigned long 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(0x10000000UL, lmb.rmo_size);
for_each_cpu(i)
paca[i].emergency_sp =
__va(lmb_alloc_base(HW_PAGE_SIZE, 128, limit)) + HW_PAGE_SIZE;
}
/*
* Called into from start_kernel, after lock_kernel has been called.
* Initializes bootmem, which is unsed to manage page allocation until
* mem_init is called.
*/
void __init setup_arch(char **cmdline_p)
{
extern void do_init_bootmem(void);
ppc64_boot_msg(0x12, "Setup Arch");
*cmdline_p = cmd_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;
/* reboot on panic */
panic_timeout = 180;
if (ppc_md.panic)
notifier_chain_register(&panic_notifier_list, &ppc64_panic_block);
init_mm.start_code = PAGE_OFFSET;
init_mm.end_code = (unsigned long) _etext;
init_mm.end_data = (unsigned long) _edata;
init_mm.brk = klimit;
irqstack_early_init();
emergency_stack_init();
stabs_alloc();
/* set up the bootmem stuff with available memory */
do_init_bootmem();
sparse_init();
#ifdef CONFIG_DUMMY_CONSOLE
conswitchp = &dummy_con;
#endif
ppc_md.setup_arch();
/* Use the default idle loop if the platform hasn't provided one. */
if (NULL == ppc_md.idle_loop) {
ppc_md.idle_loop = default_idle;
printk(KERN_INFO "Using default idle loop\n");
}
paging_init();
ppc64_boot_msg(0x15, "Setup Done");
}
/* ToDo: do something useful if ppc_md is not yet setup. */
#define PPC64_LINUX_FUNCTION 0x0f000000
#define PPC64_IPL_MESSAGE 0xc0000000
#define PPC64_TERM_MESSAGE 0xb0000000
static void ppc64_do_msg(unsigned int src, const char *msg)
{
if (ppc_md.progress) {
char buf[128];
sprintf(buf, "%08X\n", src);
ppc_md.progress(buf, 0);
snprintf(buf, 128, "%s", msg);
ppc_md.progress(buf, 0);
}
}
/* Print a boot progress message. */
void ppc64_boot_msg(unsigned int src, const char *msg)
{
ppc64_do_msg(PPC64_LINUX_FUNCTION|PPC64_IPL_MESSAGE|src, msg);
printk("[boot]%04x %s\n", src, msg);
}
/* Print a termination message (print only -- does not stop the kernel) */
void ppc64_terminate_msg(unsigned int src, const char *msg)
{
ppc64_do_msg(PPC64_LINUX_FUNCTION|PPC64_TERM_MESSAGE|src, msg);
printk("[terminate]%04x %s\n", src, msg);
}
int check_legacy_ioport(unsigned long base_port)
{
if (ppc_md.check_legacy_ioport == NULL)
return 0;
return ppc_md.check_legacy_ioport(base_port);
}
EXPORT_SYMBOL(check_legacy_ioport);
void cpu_die(void)
{
if (ppc_md.cpu_die)
ppc_md.cpu_die();
}
#ifdef CONFIG_SMP
void __init setup_per_cpu_areas(void)
{
int i;
unsigned long size;
char *ptr;
/* Copy section for each CPU (we discard the original) */
size = ALIGN(__per_cpu_end - __per_cpu_start, SMP_CACHE_BYTES);
#ifdef CONFIG_MODULES
if (size < PERCPU_ENOUGH_ROOM)
size = PERCPU_ENOUGH_ROOM;
#endif
for_each_cpu(i) {
ptr = alloc_bootmem_node(NODE_DATA(cpu_to_node(i)), size);
if (!ptr)
panic("Cannot allocate cpu data for CPU %d\n", i);
paca[i].data_offset = ptr - __per_cpu_start;
memcpy(ptr, __per_cpu_start, __per_cpu_end - __per_cpu_start);
}
}
#endif