linux/arch/sparc/kernel/setup_32.c
Sam Ravnborg 1edc17832d sparc32: use flushi when run-time patching in per_cpu_patch
Davis S. Miller wrote:
"
The way we do that now is overkill.  We only needed to use the MMU
cache ops when we had sun4c around because sun4c lacked support for
the "flush" instruction.

But all sun4m and later chips have it so we can use it
unconditionally.

So in the per_cpu_patch() code, get rid of the cache ops invocation,
and instead execute a "flush %reg" after each of the instruction patch
assignments, where %reg is set to the address of the instruction that
was stored into.

Perhaps take the flushi() definition from asm/cacheflush_64.h and
place it into asm/cacheflush.h, then you can simply use that.
"

Implemented as per suggestion.
Moved run-time patching before we call paging_init(),
so helper methods in paging_init() may utilise run-time patching too.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-05-20 13:33:36 -07:00

390 lines
8.5 KiB
C

/*
* linux/arch/sparc/kernel/setup.c
*
* Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
* Copyright (C) 2000 Anton Blanchard (anton@samba.org)
*/
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/stddef.h>
#include <linux/unistd.h>
#include <linux/ptrace.h>
#include <linux/slab.h>
#include <linux/initrd.h>
#include <asm/smp.h>
#include <linux/user.h>
#include <linux/screen_info.h>
#include <linux/delay.h>
#include <linux/fs.h>
#include <linux/seq_file.h>
#include <linux/syscalls.h>
#include <linux/kdev_t.h>
#include <linux/major.h>
#include <linux/string.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/console.h>
#include <linux/spinlock.h>
#include <linux/root_dev.h>
#include <linux/cpu.h>
#include <linux/kdebug.h>
#include <linux/export.h>
#include <asm/io.h>
#include <asm/processor.h>
#include <asm/oplib.h>
#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/traps.h>
#include <asm/vaddrs.h>
#include <asm/mbus.h>
#include <asm/idprom.h>
#include <asm/cpudata.h>
#include <asm/setup.h>
#include <asm/cacheflush.h>
#include "kernel.h"
struct screen_info screen_info = {
0, 0, /* orig-x, orig-y */
0, /* unused */
0, /* orig-video-page */
0, /* orig-video-mode */
128, /* orig-video-cols */
0,0,0, /* ega_ax, ega_bx, ega_cx */
54, /* orig-video-lines */
0, /* orig-video-isVGA */
16 /* orig-video-points */
};
/* Typing sync at the prom prompt calls the function pointed to by
* romvec->pv_synchook which I set to the following function.
* This should sync all filesystems and return, for now it just
* prints out pretty messages and returns.
*/
extern unsigned long trapbase;
/* Pretty sick eh? */
static void prom_sync_me(void)
{
unsigned long prom_tbr, flags;
/* XXX Badly broken. FIX! - Anton */
local_irq_save(flags);
__asm__ __volatile__("rd %%tbr, %0\n\t" : "=r" (prom_tbr));
__asm__ __volatile__("wr %0, 0x0, %%tbr\n\t"
"nop\n\t"
"nop\n\t"
"nop\n\t" : : "r" (&trapbase));
prom_printf("PROM SYNC COMMAND...\n");
show_free_areas(0);
if (!is_idle_task(current)) {
local_irq_enable();
sys_sync();
local_irq_disable();
}
prom_printf("Returning to prom\n");
__asm__ __volatile__("wr %0, 0x0, %%tbr\n\t"
"nop\n\t"
"nop\n\t"
"nop\n\t" : : "r" (prom_tbr));
local_irq_restore(flags);
}
static unsigned int boot_flags __initdata = 0;
#define BOOTME_DEBUG 0x1
/* Exported for mm/init.c:paging_init. */
unsigned long cmdline_memory_size __initdata = 0;
/* which CPU booted us (0xff = not set) */
unsigned char boot_cpu_id = 0xff; /* 0xff will make it into DATA section... */
static void
prom_console_write(struct console *con, const char *s, unsigned n)
{
prom_write(s, n);
}
static struct console prom_early_console = {
.name = "earlyprom",
.write = prom_console_write,
.flags = CON_PRINTBUFFER | CON_BOOT,
.index = -1,
};
/*
* Process kernel command line switches that are specific to the
* SPARC or that require special low-level processing.
*/
static void __init process_switch(char c)
{
switch (c) {
case 'd':
boot_flags |= BOOTME_DEBUG;
break;
case 's':
break;
case 'h':
prom_printf("boot_flags_init: Halt!\n");
prom_halt();
break;
case 'p':
prom_early_console.flags &= ~CON_BOOT;
break;
default:
printk("Unknown boot switch (-%c)\n", c);
break;
}
}
static void __init boot_flags_init(char *commands)
{
while (*commands) {
/* Move to the start of the next "argument". */
while (*commands && *commands == ' ')
commands++;
/* Process any command switches, otherwise skip it. */
if (*commands == '\0')
break;
if (*commands == '-') {
commands++;
while (*commands && *commands != ' ')
process_switch(*commands++);
continue;
}
if (!strncmp(commands, "mem=", 4)) {
/*
* "mem=XXX[kKmM] overrides the PROM-reported
* memory size.
*/
cmdline_memory_size = simple_strtoul(commands + 4,
&commands, 0);
if (*commands == 'K' || *commands == 'k') {
cmdline_memory_size <<= 10;
commands++;
} else if (*commands=='M' || *commands=='m') {
cmdline_memory_size <<= 20;
commands++;
}
}
while (*commands && *commands != ' ')
commands++;
}
}
extern unsigned short root_flags;
extern unsigned short root_dev;
extern unsigned short ram_flags;
#define RAMDISK_IMAGE_START_MASK 0x07FF
#define RAMDISK_PROMPT_FLAG 0x8000
#define RAMDISK_LOAD_FLAG 0x4000
extern int root_mountflags;
char reboot_command[COMMAND_LINE_SIZE];
struct cpuid_patch_entry {
unsigned int addr;
unsigned int sun4d[3];
unsigned int leon[3];
};
extern struct cpuid_patch_entry __cpuid_patch, __cpuid_patch_end;
static void __init per_cpu_patch(void)
{
struct cpuid_patch_entry *p;
if (sparc_cpu_model == sun4m) {
/* Nothing to do, this is what the unpatched code
* targets.
*/
return;
}
p = &__cpuid_patch;
while (p < &__cpuid_patch_end) {
unsigned long addr = p->addr;
unsigned int *insns;
switch (sparc_cpu_model) {
case sun4d:
insns = &p->sun4d[0];
break;
case sparc_leon:
insns = &p->leon[0];
break;
default:
prom_printf("Unknown cpu type, halting.\n");
prom_halt();
}
*(unsigned int *) (addr + 0) = insns[0];
flushi(addr + 0);
*(unsigned int *) (addr + 4) = insns[1];
flushi(addr + 4);
*(unsigned int *) (addr + 8) = insns[2];
flushi(addr + 8);
p++;
}
}
enum sparc_cpu sparc_cpu_model;
EXPORT_SYMBOL(sparc_cpu_model);
struct tt_entry *sparc_ttable;
struct pt_regs fake_swapper_regs;
void __init setup_arch(char **cmdline_p)
{
int i;
unsigned long highest_paddr;
sparc_ttable = (struct tt_entry *) &trapbase;
/* Initialize PROM console and command line. */
*cmdline_p = prom_getbootargs();
strcpy(boot_command_line, *cmdline_p);
parse_early_param();
boot_flags_init(*cmdline_p);
register_console(&prom_early_console);
/* Set sparc_cpu_model */
sparc_cpu_model = sun_unknown;
if (!strcmp(&cputypval[0], "sun4m"))
sparc_cpu_model = sun4m;
if (!strcmp(&cputypval[0], "sun4s"))
sparc_cpu_model = sun4m; /* CP-1200 with PROM 2.30 -E */
if (!strcmp(&cputypval[0], "sun4d"))
sparc_cpu_model = sun4d;
if (!strcmp(&cputypval[0], "sun4e"))
sparc_cpu_model = sun4e;
if (!strcmp(&cputypval[0], "sun4u"))
sparc_cpu_model = sun4u;
if (!strncmp(&cputypval[0], "leon" , 4))
sparc_cpu_model = sparc_leon;
printk("ARCH: ");
switch(sparc_cpu_model) {
case sun4m:
printk("SUN4M\n");
break;
case sun4d:
printk("SUN4D\n");
break;
case sun4e:
printk("SUN4E\n");
break;
case sun4u:
printk("SUN4U\n");
break;
case sparc_leon:
printk("LEON\n");
break;
default:
printk("UNKNOWN!\n");
break;
}
#ifdef CONFIG_DUMMY_CONSOLE
conswitchp = &dummy_con;
#endif
idprom_init();
load_mmu();
phys_base = 0xffffffffUL;
highest_paddr = 0UL;
for (i = 0; sp_banks[i].num_bytes != 0; i++) {
unsigned long top;
if (sp_banks[i].base_addr < phys_base)
phys_base = sp_banks[i].base_addr;
top = sp_banks[i].base_addr +
sp_banks[i].num_bytes;
if (highest_paddr < top)
highest_paddr = top;
}
pfn_base = phys_base >> PAGE_SHIFT;
if (!root_flags)
root_mountflags &= ~MS_RDONLY;
ROOT_DEV = old_decode_dev(root_dev);
#ifdef CONFIG_BLK_DEV_RAM
rd_image_start = ram_flags & RAMDISK_IMAGE_START_MASK;
rd_prompt = ((ram_flags & RAMDISK_PROMPT_FLAG) != 0);
rd_doload = ((ram_flags & RAMDISK_LOAD_FLAG) != 0);
#endif
prom_setsync(prom_sync_me);
if((boot_flags&BOOTME_DEBUG) && (linux_dbvec!=0) &&
((*(short *)linux_dbvec) != -1)) {
printk("Booted under KADB. Syncing trap table.\n");
(*(linux_dbvec->teach_debugger))();
}
init_mm.context = (unsigned long) NO_CONTEXT;
init_task.thread.kregs = &fake_swapper_regs;
/* Run-time patch instructions to match the cpu model */
per_cpu_patch();
paging_init();
smp_setup_cpu_possible_map();
}
extern int stop_a_enabled;
void sun_do_break(void)
{
if (!stop_a_enabled)
return;
printk("\n");
flush_user_windows();
prom_cmdline();
}
EXPORT_SYMBOL(sun_do_break);
int stop_a_enabled = 1;
static int __init topology_init(void)
{
int i, ncpus, err;
/* Count the number of physically present processors in
* the machine, even on uniprocessor, so that /proc/cpuinfo
* output is consistent with 2.4.x
*/
ncpus = 0;
while (!cpu_find_by_instance(ncpus, NULL, NULL))
ncpus++;
ncpus_probed = ncpus;
err = 0;
for_each_online_cpu(i) {
struct cpu *p = kzalloc(sizeof(*p), GFP_KERNEL);
if (!p)
err = -ENOMEM;
else
register_cpu(p, i);
}
return err;
}
subsys_initcall(topology_init);