android_kernel_xiaomi_sm8350/arch/powerpc/kernel/setup_64.c
Benjamin Herrenschmidt 0909c8c2d5 [POWERPC] Support feature fixups in vdso's
This patch reworks the feature fixup mecanism so vdso's can be fixed up.
The main issue was that the construct:

        .long   label  (or .llong on 64 bits)

will not work in the case of a shared library like the vdso. It will
generate an empty placeholder in the fixup table along with a reloc,
which is not something we can deal with in the vdso.

The idea here (thanks Alan Modra !) is to instead use something like:

1:
        .long   label - 1b

That is, the feature fixup tables no longer contain addresses of bits of
code to patch, but offsets of such code from the fixup table entry
itself. That is properly resolved by ld when building the .so's. I've
modified the fixup mecanism generically to use that method for the rest
of the kernel as well.

Another trick is that the 32 bits vDSO included in the 64 bits kernel
need to have a table in the 64 bits format. However, gas does not
support 32 bits code with a statement of the form:

        .llong  label - 1b  (Or even just .llong label)

That is, it cannot emit the right fixup/relocation for the linker to use
to assign a 32 bits address to an .llong field. Thus, in the specific
case of the 32 bits vdso built as part of the 64 bits kernel, we are
using a modified macro that generates:

        .long   0xffffffff
        .llong  label - 1b

Note that is assumes that the value is negative which is enforced by
the .lds (those offsets are always negative as the .text is always
before the fixup table and gas doesn't support emiting the reloc the
other way around).

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-10-25 11:54:07 +10:00

601 lines
15 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/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/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;
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 = 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 = 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)
{
/* Identify CPU type */
identify_cpu(0);
/* Assume we're on cpu 0 for now. Don't write to the paca yet! */
setup_paca(0);
/* Enable early debugging if any specified (see udbg.h) */
udbg_early_init();
DBG(" -> early_setup(), dt_ptr: 0x%lx\n", dt_ptr);
/*
* 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));
/* 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 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");
}
#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;
const char *dc, *ic;
/* Then read cache informations */
if (machine_is(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 = get_property(np, "d-cache-size", NULL);
if (sizep != NULL)
size = *sizep;
lsizep = 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 = get_property(np, "i-cache-size", NULL);
if (sizep != NULL)
size = *sizep;
lsizep = 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");
/* 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);
/*
* 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()
*/
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());
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");
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)
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)
{
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 = 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();
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, SMP_CACHE_BYTES);
#ifdef CONFIG_MODULES
if (size < PERCPU_ENOUGH_ROOM)
size = PERCPU_ENOUGH_ROOM;
#endif
for_each_possible_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