kernel-fxtec-pro1x/arch/powerpc/kernel/setup_64.c
Paul Mackerras 1f6a93e4c3 powerpc: Make it possible to move the interrupt handlers away from the kernel
This changes the way that the exception prologs transfer control to
the handlers in 64-bit kernels with the aim of making it possible to
have the prologs separate from the main body of the kernel.  Now,
instead of computing the address of the handler by taking the top
32 bits of the paca address (to get the 0xc0000000........ part) and
ORing in something in the bottom 16 bits, we get the base address of
the kernel by doing a load from the paca and add an offset.

This also replaces an mfmsr and an ori to compute the MSR value for
the handler with a load from the paca.  That makes it unnecessary to
have a separate version of EXCEPTION_PROLOG_PSERIES that forces 64-bit
mode.

We can no longer use a direct branches in the exception prolog code,
which means that the SLB miss handlers can't branch directly to
.slb_miss_realmode any more.  Instead we have to compute the address
and do an indirect branch.  This is conditional on CONFIG_RELOCATABLE;
for non-relocatable kernels we use a direct branch as before.  (A later
change will allow CONFIG_RELOCATABLE to be set on 64-bit powerpc.)

Since the secondary CPUs on pSeries start execution in the first 0x100
bytes of real memory and then have to get to wherever the kernel is,
we can't use a direct branch to get there.  Instead this changes
__secondary_hold_spinloop from a flag to a function pointer.  When it
is set to a non-NULL value, the secondary CPUs jump to the function
pointed to by that value.

Finally this eliminates one code difference between 32-bit and 64-bit
by making __secondary_hold be the text address of the secondary CPU
spinloop rather than a function descriptor for it.

Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-09-15 11:08:08 -07:00

623 lines
16 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/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/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/lmb.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/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;
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;
#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;
const 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 = of_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 */
/* Put the paca pointer into r13 and SPRG3 */
void __init setup_paca(int cpu)
{
local_paca = &paca[cpu];
mtspr(SPRN_SPRG3, local_paca);
}
/*
* 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)
{
/* -------- printk is _NOT_ safe to use here ! ------- */
/* Fill in any unititialised pacas */
initialise_pacas();
/* Identify CPU type */
identify_cpu(0, mfspr(SPRN_PVR));
/* Assume we're on cpu 0 for now. Don't write to the paca yet! */
setup_paca(0);
/* 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));
/* Now we know the logical id of our boot cpu, setup the paca. */
setup_paca(boot_cpuid);
/* Fix up paca fields required for the boot cpu */
get_paca()->cpu_start = 1;
get_paca()->stab_real = __pa((u64)&initial_stab);
get_paca()->stab_addr = (u64)&initial_stab;
/* Probe the machine type */
probe_machine();
setup_kdump_trampoline();
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 (cpu_has_feature(CPU_FTR_SLB))
slb_initialize();
else if (!firmware_has_feature(FW_FEATURE_ISERIES))
stab_initialize(get_paca()->stab_real);
DBG(" <- early_setup()\n");
}
#ifdef CONFIG_SMP
void early_setup_secondary(void)
{
struct paca_struct *lpaca = get_paca();
/* Mark interrupts enabled in PACA */
lpaca->soft_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)
extern unsigned long __secondary_hold_spinloop;
extern void generic_secondary_smp_init(void);
void smp_release_cpus(void)
{
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.
*/
ptr = (unsigned long *)((unsigned long)&__secondary_hold_spinloop
- PHYSICAL_START);
*ptr = __pa(generic_secondary_smp_init);
mb();
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 (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 ) {
const u32 *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 = *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 = *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 = of_get_property(np, "i-cache-size", NULL);
if (sizep != NULL)
size = *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 = *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");
/* 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(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);
/*
* 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();
/*
* Initialize irq remapping subsystem
*/
irq_early_init();
#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();
check_smt_enabled();
smp_setup_cpu_maps();
#ifdef CONFIG_SMP
/* Release secondary cpus out of their spinloops at 0x60 now that
* we can map physical -> logical CPU ids
*/
smp_release_cpus();
#endif
printk("Starting Linux PPC64 %s\n", init_utsname()->version);
printk("-----------------------------------------------------\n");
printk("ppc64_pft_size = 0x%lx\n", ppc64_pft_size);
printk("physicalMemorySize = 0x%lx\n", lmb_phys_mem_size());
if (ppc64_caches.dline_size != 0x80)
printk("ppc64_caches.dcache_line_size = 0x%x\n",
ppc64_caches.dline_size);
if (ppc64_caches.iline_size != 0x80)
printk("ppc64_caches.icache_line_size = 0x%x\n",
ppc64_caches.iline_size);
if (htab_address)
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%lx\n", PHYSICAL_START);
#endif
printk("-----------------------------------------------------\n");
DBG(" <- setup_system()\n");
}
#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_possible_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_possible_cpu(i) {
unsigned long sp;
sp = lmb_alloc_base(THREAD_SIZE, THREAD_SIZE, limit);
sp += THREAD_SIZE;
paca[i].emergency_sp = __va(sp);
}
}
/*
* 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)
{
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)
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;
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
if (ppc_md.setup_arch)
ppc_md.setup_arch();
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);
}
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, PAGE_SIZE);
#ifdef CONFIG_MODULES
if (size < PERCPU_ENOUGH_ROOM)
size = PERCPU_ENOUGH_ROOM;
#endif
for_each_possible_cpu(i) {
ptr = alloc_bootmem_pages_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
#ifdef CONFIG_PPC_INDIRECT_IO
struct ppc_pci_io ppc_pci_io;
EXPORT_SYMBOL(ppc_pci_io);
#endif /* CONFIG_PPC_INDIRECT_IO */