linux/arch/ppc/kernel/setup.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

570 lines
13 KiB
C

/*
* Common prep boot and setup code.
*/
#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/screen_info.h>
#include <linux/bootmem.h>
#include <linux/seq_file.h>
#include <linux/root_dev.h>
#include <linux/cpu.h>
#include <linux/console.h>
#include <asm/residual.h>
#include <asm/io.h>
#include <asm/prom.h>
#include <asm/processor.h>
#include <asm/pgtable.h>
#include <asm/bootinfo.h>
#include <asm/setup.h>
#include <asm/amigappc.h>
#include <asm/smp.h>
#include <asm/elf.h>
#include <asm/cputable.h>
#include <asm/bootx.h>
#include <asm/btext.h>
#include <asm/machdep.h>
#include <asm/uaccess.h>
#include <asm/system.h>
#include <asm/sections.h>
#include <asm/nvram.h>
#include <asm/xmon.h>
#include <asm/ocp.h>
#include <asm/prom.h>
#define USES_PPC_SYS (defined(CONFIG_85xx) || defined(CONFIG_83xx) || \
defined(CONFIG_MPC10X_BRIDGE) || defined(CONFIG_8260) || \
defined(CONFIG_PPC_MPC52xx))
#if USES_PPC_SYS
#include <asm/ppc_sys.h>
#endif
#if defined CONFIG_KGDB
#include <asm/kgdb.h>
#endif
extern void platform_init(unsigned long r3, unsigned long r4,
unsigned long r5, unsigned long r6, unsigned long r7);
extern void reloc_got2(unsigned long offset);
extern void ppc6xx_idle(void);
extern void power4_idle(void);
extern boot_infos_t *boot_infos;
struct ide_machdep_calls ppc_ide_md;
/* Used with the BI_MEMSIZE bootinfo parameter to store the memory
size value reported by the boot loader. */
unsigned long boot_mem_size;
unsigned long ISA_DMA_THRESHOLD;
unsigned int DMA_MODE_READ;
unsigned int DMA_MODE_WRITE;
#ifdef CONFIG_PPC_PREP
extern void prep_init(unsigned long r3, unsigned long r4,
unsigned long r5, unsigned long r6, unsigned long r7);
dev_t boot_dev;
#endif /* CONFIG_PPC_PREP */
int have_of;
EXPORT_SYMBOL(have_of);
#ifdef __DO_IRQ_CANON
int ppc_do_canonicalize_irqs;
EXPORT_SYMBOL(ppc_do_canonicalize_irqs);
#endif
#ifdef CONFIG_VGA_CONSOLE
unsigned long vgacon_remap_base;
#endif
struct machdep_calls ppc_md;
/*
* 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_VGA_CONSOLE) || defined(CONFIG_FB_VGA16) || \
defined(CONFIG_FB_VGA16_MODULE) || defined(CONFIG_FB_VESA)
struct screen_info screen_info = {
0, 25, /* orig-x, orig-y */
0, /* unused */
0, /* orig-video-page */
0, /* orig-video-mode */
80, /* orig-video-cols */
0,0,0, /* ega_ax, ega_bx, ega_cx */
25, /* orig-video-lines */
1, /* orig-video-isVGA */
16 /* orig-video-points */
};
#endif /* CONFIG_VGA_CONSOLE || CONFIG_FB_VGA16 || CONFIG_FB_VESA */
void machine_restart(char *cmd)
{
#ifdef CONFIG_NVRAM
nvram_sync();
#endif
ppc_md.restart(cmd);
}
static void ppc_generic_power_off(void)
{
ppc_md.power_off();
}
void machine_halt(void)
{
#ifdef CONFIG_NVRAM
nvram_sync();
#endif
ppc_md.halt();
}
void (*pm_power_off)(void) = ppc_generic_power_off;
void machine_power_off(void)
{
#ifdef CONFIG_NVRAM
nvram_sync();
#endif
if (pm_power_off)
pm_power_off();
ppc_generic_power_off();
}
#ifdef CONFIG_TAU
extern u32 cpu_temp(unsigned long cpu);
extern u32 cpu_temp_both(unsigned long cpu);
#endif /* CONFIG_TAU */
int show_cpuinfo(struct seq_file *m, void *v)
{
int i = (int) v - 1;
int err = 0;
unsigned int pvr;
unsigned short maj, min;
unsigned long lpj;
if (i >= NR_CPUS) {
/* Show summary information */
#ifdef CONFIG_SMP
unsigned long bogosum = 0;
for_each_online_cpu(i)
bogosum += cpu_data[i].loops_per_jiffy;
seq_printf(m, "total bogomips\t: %lu.%02lu\n",
bogosum/(500000/HZ), bogosum/(5000/HZ) % 100);
#endif /* CONFIG_SMP */
if (ppc_md.show_cpuinfo != NULL)
err = ppc_md.show_cpuinfo(m);
return err;
}
#ifdef CONFIG_SMP
if (!cpu_online(i))
return 0;
pvr = cpu_data[i].pvr;
lpj = cpu_data[i].loops_per_jiffy;
#else
pvr = mfspr(SPRN_PVR);
lpj = loops_per_jiffy;
#endif
seq_printf(m, "processor\t: %d\n", i);
seq_printf(m, "cpu\t\t: ");
if (cur_cpu_spec->pvr_mask)
seq_printf(m, "%s", cur_cpu_spec->cpu_name);
else
seq_printf(m, "unknown (%08x)", pvr);
#ifdef CONFIG_ALTIVEC
if (cur_cpu_spec->cpu_features & CPU_FTR_ALTIVEC)
seq_printf(m, ", altivec supported");
#endif
seq_printf(m, "\n");
#ifdef CONFIG_TAU
if (cur_cpu_spec->cpu_features & CPU_FTR_TAU) {
#ifdef CONFIG_TAU_AVERAGE
/* more straightforward, but potentially misleading */
seq_printf(m, "temperature \t: %u C (uncalibrated)\n",
cpu_temp(i));
#else
/* show the actual temp sensor range */
u32 temp;
temp = cpu_temp_both(i);
seq_printf(m, "temperature \t: %u-%u C (uncalibrated)\n",
temp & 0xff, temp >> 16);
#endif
}
#endif /* CONFIG_TAU */
if (ppc_md.show_percpuinfo != NULL) {
err = ppc_md.show_percpuinfo(m, i);
if (err)
return err;
}
/* If we are a Freescale core do a simple check so
* we dont have to keep adding cases in the future */
if ((PVR_VER(pvr) & 0x8000) == 0x8000) {
maj = PVR_MAJ(pvr);
min = PVR_MIN(pvr);
} else {
switch (PVR_VER(pvr)) {
case 0x0020: /* 403 family */
maj = PVR_MAJ(pvr) + 1;
min = PVR_MIN(pvr);
break;
case 0x1008: /* 740P/750P ?? */
maj = ((pvr >> 8) & 0xFF) - 1;
min = pvr & 0xFF;
break;
default:
maj = (pvr >> 8) & 0xFF;
min = pvr & 0xFF;
break;
}
}
seq_printf(m, "revision\t: %hd.%hd (pvr %04x %04x)\n",
maj, min, PVR_VER(pvr), PVR_REV(pvr));
seq_printf(m, "bogomips\t: %lu.%02lu\n",
lpj / (500000/HZ), (lpj / (5000/HZ)) % 100);
#if USES_PPC_SYS
if (cur_ppc_sys_spec->ppc_sys_name)
seq_printf(m, "chipset\t\t: %s\n",
cur_ppc_sys_spec->ppc_sys_name);
#endif
#ifdef CONFIG_SMP
seq_printf(m, "\n");
#endif
return 0;
}
static void *c_start(struct seq_file *m, loff_t *pos)
{
int i = *pos;
return i <= NR_CPUS? (void *) (i + 1): NULL;
}
static void *c_next(struct seq_file *m, void *v, loff_t *pos)
{
++*pos;
return c_start(m, pos);
}
static void c_stop(struct seq_file *m, void *v)
{
}
struct seq_operations cpuinfo_op = {
.start =c_start,
.next = c_next,
.stop = c_stop,
.show = show_cpuinfo,
};
/*
* We're called here very early in the boot. We determine the machine
* type and call the appropriate low-level setup functions.
* -- Cort <cort@fsmlabs.com>
*
* Note that the kernel may be running at an address which is different
* from the address that it was linked at, so we must use RELOC/PTRRELOC
* to access static data (including strings). -- paulus
*/
__init
unsigned long
early_init(int r3, int r4, int r5)
{
unsigned long phys;
unsigned long offset = reloc_offset();
struct cpu_spec *spec;
/* Default */
phys = offset + KERNELBASE;
/* First zero the BSS -- use memset, some arches don't have
* caches on yet */
memset_io(PTRRELOC(&__bss_start), 0, _end - __bss_start);
/*
* Identify the CPU type and fix up code sections
* that depend on which cpu we have.
*/
spec = identify_cpu(offset);
do_feature_fixups(spec->cpu_features,
PTRRELOC(&__start___ftr_fixup),
PTRRELOC(&__stop___ftr_fixup));
return phys;
}
#ifdef CONFIG_PPC_PREP
/*
* The PPC_PREP version of platform_init...
*/
void __init
platform_init(unsigned long r3, unsigned long r4, unsigned long r5,
unsigned long r6, unsigned long r7)
{
#ifdef CONFIG_BOOTX_TEXT
if (boot_text_mapped) {
btext_clearscreen();
btext_welcome();
}
#endif
parse_bootinfo(find_bootinfo());
prep_init(r3, r4, r5, r6, r7);
}
#endif /* CONFIG_PPC_PREP */
struct bi_record *find_bootinfo(void)
{
struct bi_record *rec;
rec = (struct bi_record *)_ALIGN((ulong)__bss_start+(1<<20)-1,(1<<20));
if ( rec->tag != BI_FIRST ) {
/*
* This 0x10000 offset is a terrible hack but it will go away when
* we have the bootloader handle all the relocation and
* prom calls -- Cort
*/
rec = (struct bi_record *)_ALIGN((ulong)__bss_start+0x10000+(1<<20)-1,(1<<20));
if ( rec->tag != BI_FIRST )
return NULL;
}
return rec;
}
void parse_bootinfo(struct bi_record *rec)
{
if (rec == NULL || rec->tag != BI_FIRST)
return;
while (rec->tag != BI_LAST) {
ulong *data = rec->data;
switch (rec->tag) {
case BI_CMD_LINE:
strlcpy(cmd_line, (void *)data, sizeof(cmd_line));
break;
#ifdef CONFIG_BLK_DEV_INITRD
case BI_INITRD:
initrd_start = data[0] + KERNELBASE;
initrd_end = data[0] + data[1] + KERNELBASE;
break;
#endif /* CONFIG_BLK_DEV_INITRD */
case BI_MEMSIZE:
boot_mem_size = data[0];
break;
}
rec = (struct bi_record *)((ulong)rec + rec->size);
}
}
/*
* Find out what kind of machine we're on and save any data we need
* from the early boot process (devtree is copied on pmac by prom_init()).
* This is called very early on the boot process, after a minimal
* MMU environment has been set up but before MMU_init is called.
*/
void __init
machine_init(unsigned long r3, unsigned long r4, unsigned long r5,
unsigned long r6, unsigned long r7)
{
#ifdef CONFIG_CMDLINE
strlcpy(cmd_line, CONFIG_CMDLINE, sizeof(cmd_line));
#endif /* CONFIG_CMDLINE */
#ifdef CONFIG_6xx
ppc_md.power_save = ppc6xx_idle;
#endif
platform_init(r3, r4, r5, r6, r7);
if (ppc_md.progress)
ppc_md.progress("id mach(): done", 0x200);
}
#ifdef CONFIG_BOOKE_WDT
/* Checks wdt=x and wdt_period=xx command-line option */
int __init early_parse_wdt(char *p)
{
if (p && strncmp(p, "0", 1) != 0)
booke_wdt_enabled = 1;
return 0;
}
early_param("wdt", early_parse_wdt);
int __init early_parse_wdt_period (char *p)
{
if (p)
booke_wdt_period = simple_strtoul(p, NULL, 0);
return 0;
}
early_param("wdt_period", early_parse_wdt_period);
#endif /* CONFIG_BOOKE_WDT */
/* Checks "l2cr=xxxx" command-line option */
int __init ppc_setup_l2cr(char *str)
{
if (cpu_has_feature(CPU_FTR_L2CR)) {
unsigned long val = simple_strtoul(str, NULL, 0);
printk(KERN_INFO "l2cr set to %lx\n", val);
_set_L2CR(0); /* force invalidate by disable cache */
_set_L2CR(val); /* and enable it */
}
return 1;
}
__setup("l2cr=", ppc_setup_l2cr);
#ifdef CONFIG_GENERIC_NVRAM
/* Generic nvram hooks used by drivers/char/gen_nvram.c */
unsigned char nvram_read_byte(int addr)
{
if (ppc_md.nvram_read_val)
return ppc_md.nvram_read_val(addr);
return 0xff;
}
EXPORT_SYMBOL(nvram_read_byte);
void nvram_write_byte(unsigned char val, int addr)
{
if (ppc_md.nvram_write_val)
ppc_md.nvram_write_val(addr, val);
}
EXPORT_SYMBOL(nvram_write_byte);
void nvram_sync(void)
{
if (ppc_md.nvram_sync)
ppc_md.nvram_sync();
}
EXPORT_SYMBOL(nvram_sync);
#endif /* CONFIG_NVRAM */
static struct cpu cpu_devices[NR_CPUS];
int __init ppc_init(void)
{
int i;
/* clear the progress line */
if ( ppc_md.progress ) ppc_md.progress(" ", 0xffff);
/* register CPU devices */
for_each_possible_cpu(i)
register_cpu(&cpu_devices[i], i);
/* call platform init */
if (ppc_md.init != NULL) {
ppc_md.init();
}
return 0;
}
arch_initcall(ppc_init);
/* Warning, IO base is not yet inited */
void __init setup_arch(char **cmdline_p)
{
extern char *klimit;
extern void do_init_bootmem(void);
/* so udelay does something sensible, assume <= 1000 bogomips */
loops_per_jiffy = 500000000 / HZ;
if (ppc_md.init_early)
ppc_md.init_early();
#ifdef CONFIG_XMON
xmon_init(1);
if (strstr(cmd_line, "xmon"))
xmon(NULL);
#endif /* CONFIG_XMON */
if ( ppc_md.progress ) ppc_md.progress("setup_arch: enter", 0x3eab);
#if defined(CONFIG_KGDB)
if (ppc_md.kgdb_map_scc)
ppc_md.kgdb_map_scc();
set_debug_traps();
if (strstr(cmd_line, "gdb")) {
if (ppc_md.progress)
ppc_md.progress("setup_arch: kgdb breakpoint", 0x4000);
printk("kgdb breakpoint activated\n");
breakpoint();
}
#endif
/*
* 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.
*/
if (cpu_has_feature(CPU_FTR_SPLIT_ID_CACHE)) {
dcache_bsize = cur_cpu_spec->dcache_bsize;
icache_bsize = cur_cpu_spec->icache_bsize;
ucache_bsize = 0;
} else
ucache_bsize = dcache_bsize = icache_bsize
= cur_cpu_spec->dcache_bsize;
/* reboot on panic */
panic_timeout = 180;
init_mm.start_code = PAGE_OFFSET;
init_mm.end_code = (unsigned long) _etext;
init_mm.end_data = (unsigned long) _edata;
init_mm.brk = (unsigned long) klimit;
/* Save unparsed command line copy for /proc/cmdline */
strlcpy(saved_command_line, cmd_line, COMMAND_LINE_SIZE);
*cmdline_p = cmd_line;
parse_early_param();
/* set up the bootmem stuff with available memory */
do_init_bootmem();
if ( ppc_md.progress ) ppc_md.progress("setup_arch: bootmem", 0x3eab);
#ifdef CONFIG_PPC_OCP
/* Initialize OCP device list */
ocp_early_init();
if ( ppc_md.progress ) ppc_md.progress("ocp: exit", 0x3eab);
#endif
#ifdef CONFIG_DUMMY_CONSOLE
conswitchp = &dummy_con;
#endif
ppc_md.setup_arch();
if ( ppc_md.progress ) ppc_md.progress("arch: exit", 0x3eab);
paging_init();
}