kernel-ark/arch/powerpc/platforms/powermac/smp.c
Paul Mackerras d6a29252ad [POWERPC] Fix secondary CPU startup on old "powersurge" SMP powermacs
On the old "powersurge" SMP powermacs, the second CPU is started up
by sending it an IPI, which has the side effect of stopping the
timebase clock (so the secondary CPU's timebase can be synchronized
with the primary's).  The routine that did this used udelay, which
will hang forever when the timebase is stopped, since udelay now spins
until the timebase reaches a certain value.

The end result is that the kernel would hang when bringing up the
second CPU.  This fixes it by using a simple loop which just does a
fixed number of iterations to generate the delay.  These old systems
were all clocked at around 200 MHz or so, so a fixed number of
iterations is acceptable.

Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-10-10 13:51:00 +10:00

916 lines
22 KiB
C

/*
* SMP support for power macintosh.
*
* We support both the old "powersurge" SMP architecture
* and the current Core99 (G4 PowerMac) machines.
*
* Note that we don't support the very first rev. of
* Apple/DayStar 2 CPUs board, the one with the funky
* watchdog. Hopefully, none of these should be there except
* maybe internally to Apple. I should probably still add some
* code to detect this card though and disable SMP. --BenH.
*
* Support Macintosh G4 SMP by Troy Benjegerdes (hozer@drgw.net)
* and Ben Herrenschmidt <benh@kernel.crashing.org>.
*
* Support for DayStar quad CPU cards
* Copyright (C) XLR8, Inc. 1994-2000
*
* 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.
*/
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/smp.h>
#include <linux/smp_lock.h>
#include <linux/interrupt.h>
#include <linux/kernel_stat.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/spinlock.h>
#include <linux/errno.h>
#include <linux/hardirq.h>
#include <linux/cpu.h>
#include <linux/compiler.h>
#include <asm/ptrace.h>
#include <asm/atomic.h>
#include <asm/irq.h>
#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/sections.h>
#include <asm/io.h>
#include <asm/prom.h>
#include <asm/smp.h>
#include <asm/machdep.h>
#include <asm/pmac_feature.h>
#include <asm/time.h>
#include <asm/mpic.h>
#include <asm/cacheflush.h>
#include <asm/keylargo.h>
#include <asm/pmac_low_i2c.h>
#include <asm/pmac_pfunc.h>
#define DEBUG
#ifdef DEBUG
#define DBG(fmt...) udbg_printf(fmt)
#else
#define DBG(fmt...)
#endif
extern void __secondary_start_pmac_0(void);
extern int pmac_pfunc_base_install(void);
#ifdef CONFIG_PPC32
/* Sync flag for HW tb sync */
static volatile int sec_tb_reset = 0;
/*
* Powersurge (old powermac SMP) support.
*/
/* Addresses for powersurge registers */
#define HAMMERHEAD_BASE 0xf8000000
#define HHEAD_CONFIG 0x90
#define HHEAD_SEC_INTR 0xc0
/* register for interrupting the primary processor on the powersurge */
/* N.B. this is actually the ethernet ROM! */
#define PSURGE_PRI_INTR 0xf3019000
/* register for storing the start address for the secondary processor */
/* N.B. this is the PCI config space address register for the 1st bridge */
#define PSURGE_START 0xf2800000
/* Daystar/XLR8 4-CPU card */
#define PSURGE_QUAD_REG_ADDR 0xf8800000
#define PSURGE_QUAD_IRQ_SET 0
#define PSURGE_QUAD_IRQ_CLR 1
#define PSURGE_QUAD_IRQ_PRIMARY 2
#define PSURGE_QUAD_CKSTOP_CTL 3
#define PSURGE_QUAD_PRIMARY_ARB 4
#define PSURGE_QUAD_BOARD_ID 6
#define PSURGE_QUAD_WHICH_CPU 7
#define PSURGE_QUAD_CKSTOP_RDBK 8
#define PSURGE_QUAD_RESET_CTL 11
#define PSURGE_QUAD_OUT(r, v) (out_8(quad_base + ((r) << 4) + 4, (v)))
#define PSURGE_QUAD_IN(r) (in_8(quad_base + ((r) << 4) + 4) & 0x0f)
#define PSURGE_QUAD_BIS(r, v) (PSURGE_QUAD_OUT((r), PSURGE_QUAD_IN(r) | (v)))
#define PSURGE_QUAD_BIC(r, v) (PSURGE_QUAD_OUT((r), PSURGE_QUAD_IN(r) & ~(v)))
/* virtual addresses for the above */
static volatile u8 __iomem *hhead_base;
static volatile u8 __iomem *quad_base;
static volatile u32 __iomem *psurge_pri_intr;
static volatile u8 __iomem *psurge_sec_intr;
static volatile u32 __iomem *psurge_start;
/* values for psurge_type */
#define PSURGE_NONE -1
#define PSURGE_DUAL 0
#define PSURGE_QUAD_OKEE 1
#define PSURGE_QUAD_COTTON 2
#define PSURGE_QUAD_ICEGRASS 3
/* what sort of powersurge board we have */
static int psurge_type = PSURGE_NONE;
/*
* Set and clear IPIs for powersurge.
*/
static inline void psurge_set_ipi(int cpu)
{
if (psurge_type == PSURGE_NONE)
return;
if (cpu == 0)
in_be32(psurge_pri_intr);
else if (psurge_type == PSURGE_DUAL)
out_8(psurge_sec_intr, 0);
else
PSURGE_QUAD_OUT(PSURGE_QUAD_IRQ_SET, 1 << cpu);
}
static inline void psurge_clr_ipi(int cpu)
{
if (cpu > 0) {
switch(psurge_type) {
case PSURGE_DUAL:
out_8(psurge_sec_intr, ~0);
case PSURGE_NONE:
break;
default:
PSURGE_QUAD_OUT(PSURGE_QUAD_IRQ_CLR, 1 << cpu);
}
}
}
/*
* On powersurge (old SMP powermac architecture) we don't have
* separate IPIs for separate messages like openpic does. Instead
* we have a bitmap for each processor, where a 1 bit means that
* the corresponding message is pending for that processor.
* Ideally each cpu's entry would be in a different cache line.
* -- paulus.
*/
static unsigned long psurge_smp_message[NR_CPUS];
void psurge_smp_message_recv(void)
{
int cpu = smp_processor_id();
int msg;
/* clear interrupt */
psurge_clr_ipi(cpu);
if (num_online_cpus() < 2)
return;
/* make sure there is a message there */
for (msg = 0; msg < 4; msg++)
if (test_and_clear_bit(msg, &psurge_smp_message[cpu]))
smp_message_recv(msg);
}
irqreturn_t psurge_primary_intr(int irq, void *d)
{
psurge_smp_message_recv();
return IRQ_HANDLED;
}
static void smp_psurge_message_pass(int target, int msg)
{
int i;
if (num_online_cpus() < 2)
return;
for_each_online_cpu(i) {
if (target == MSG_ALL
|| (target == MSG_ALL_BUT_SELF && i != smp_processor_id())
|| target == i) {
set_bit(msg, &psurge_smp_message[i]);
psurge_set_ipi(i);
}
}
}
/*
* Determine a quad card presence. We read the board ID register, we
* force the data bus to change to something else, and we read it again.
* It it's stable, then the register probably exist (ugh !)
*/
static int __init psurge_quad_probe(void)
{
int type;
unsigned int i;
type = PSURGE_QUAD_IN(PSURGE_QUAD_BOARD_ID);
if (type < PSURGE_QUAD_OKEE || type > PSURGE_QUAD_ICEGRASS
|| type != PSURGE_QUAD_IN(PSURGE_QUAD_BOARD_ID))
return PSURGE_DUAL;
/* looks OK, try a slightly more rigorous test */
/* bogus is not necessarily cacheline-aligned,
though I don't suppose that really matters. -- paulus */
for (i = 0; i < 100; i++) {
volatile u32 bogus[8];
bogus[(0+i)%8] = 0x00000000;
bogus[(1+i)%8] = 0x55555555;
bogus[(2+i)%8] = 0xFFFFFFFF;
bogus[(3+i)%8] = 0xAAAAAAAA;
bogus[(4+i)%8] = 0x33333333;
bogus[(5+i)%8] = 0xCCCCCCCC;
bogus[(6+i)%8] = 0xCCCCCCCC;
bogus[(7+i)%8] = 0x33333333;
wmb();
asm volatile("dcbf 0,%0" : : "r" (bogus) : "memory");
mb();
if (type != PSURGE_QUAD_IN(PSURGE_QUAD_BOARD_ID))
return PSURGE_DUAL;
}
return type;
}
static void __init psurge_quad_init(void)
{
int procbits;
if (ppc_md.progress) ppc_md.progress("psurge_quad_init", 0x351);
procbits = ~PSURGE_QUAD_IN(PSURGE_QUAD_WHICH_CPU);
if (psurge_type == PSURGE_QUAD_ICEGRASS)
PSURGE_QUAD_BIS(PSURGE_QUAD_RESET_CTL, procbits);
else
PSURGE_QUAD_BIC(PSURGE_QUAD_CKSTOP_CTL, procbits);
mdelay(33);
out_8(psurge_sec_intr, ~0);
PSURGE_QUAD_OUT(PSURGE_QUAD_IRQ_CLR, procbits);
PSURGE_QUAD_BIS(PSURGE_QUAD_RESET_CTL, procbits);
if (psurge_type != PSURGE_QUAD_ICEGRASS)
PSURGE_QUAD_BIS(PSURGE_QUAD_CKSTOP_CTL, procbits);
PSURGE_QUAD_BIC(PSURGE_QUAD_PRIMARY_ARB, procbits);
mdelay(33);
PSURGE_QUAD_BIC(PSURGE_QUAD_RESET_CTL, procbits);
mdelay(33);
PSURGE_QUAD_BIS(PSURGE_QUAD_PRIMARY_ARB, procbits);
mdelay(33);
}
static int __init smp_psurge_probe(void)
{
int i, ncpus;
/* We don't do SMP on the PPC601 -- paulus */
if (PVR_VER(mfspr(SPRN_PVR)) == 1)
return 1;
/*
* The powersurge cpu board can be used in the generation
* of powermacs that have a socket for an upgradeable cpu card,
* including the 7500, 8500, 9500, 9600.
* The device tree doesn't tell you if you have 2 cpus because
* OF doesn't know anything about the 2nd processor.
* Instead we look for magic bits in magic registers,
* in the hammerhead memory controller in the case of the
* dual-cpu powersurge board. -- paulus.
*/
if (find_devices("hammerhead") == NULL)
return 1;
hhead_base = ioremap(HAMMERHEAD_BASE, 0x800);
quad_base = ioremap(PSURGE_QUAD_REG_ADDR, 1024);
psurge_sec_intr = hhead_base + HHEAD_SEC_INTR;
psurge_type = psurge_quad_probe();
if (psurge_type != PSURGE_DUAL) {
psurge_quad_init();
/* All released cards using this HW design have 4 CPUs */
ncpus = 4;
} else {
iounmap(quad_base);
if ((in_8(hhead_base + HHEAD_CONFIG) & 0x02) == 0) {
/* not a dual-cpu card */
iounmap(hhead_base);
psurge_type = PSURGE_NONE;
return 1;
}
ncpus = 2;
}
psurge_start = ioremap(PSURGE_START, 4);
psurge_pri_intr = ioremap(PSURGE_PRI_INTR, 4);
/*
* This is necessary because OF doesn't know about the
* secondary cpu(s), and thus there aren't nodes in the
* device tree for them, and smp_setup_cpu_maps hasn't
* set their bits in cpu_possible_map and cpu_present_map.
*/
if (ncpus > NR_CPUS)
ncpus = NR_CPUS;
for (i = 1; i < ncpus ; ++i) {
cpu_set(i, cpu_present_map);
cpu_set(i, cpu_possible_map);
set_hard_smp_processor_id(i, i);
}
if (ppc_md.progress) ppc_md.progress("smp_psurge_probe - done", 0x352);
return ncpus;
}
static void __init smp_psurge_kick_cpu(int nr)
{
unsigned long start = __pa(__secondary_start_pmac_0) + nr * 8;
unsigned long a;
int i;
/* may need to flush here if secondary bats aren't setup */
for (a = KERNELBASE; a < KERNELBASE + 0x800000; a += 32)
asm volatile("dcbf 0,%0" : : "r" (a) : "memory");
asm volatile("sync");
if (ppc_md.progress) ppc_md.progress("smp_psurge_kick_cpu", 0x353);
out_be32(psurge_start, start);
mb();
psurge_set_ipi(nr);
/*
* We can't use udelay here because the timebase is now frozen.
*/
for (i = 0; i < 2000; ++i)
barrier();
psurge_clr_ipi(nr);
if (ppc_md.progress) ppc_md.progress("smp_psurge_kick_cpu - done", 0x354);
}
/*
* With the dual-cpu powersurge board, the decrementers and timebases
* of both cpus are frozen after the secondary cpu is started up,
* until we give the secondary cpu another interrupt. This routine
* uses this to get the timebases synchronized.
* -- paulus.
*/
static void __init psurge_dual_sync_tb(int cpu_nr)
{
int t;
set_dec(tb_ticks_per_jiffy);
/* XXX fixme */
set_tb(0, 0);
if (cpu_nr > 0) {
mb();
sec_tb_reset = 1;
return;
}
/* wait for the secondary to have reset its TB before proceeding */
for (t = 10000000; t > 0 && !sec_tb_reset; --t)
;
/* now interrupt the secondary, starting both TBs */
psurge_set_ipi(1);
}
static struct irqaction psurge_irqaction = {
.handler = psurge_primary_intr,
.flags = IRQF_DISABLED,
.mask = CPU_MASK_NONE,
.name = "primary IPI",
};
static void __init smp_psurge_setup_cpu(int cpu_nr)
{
if (cpu_nr == 0) {
/* If we failed to start the second CPU, we should still
* send it an IPI to start the timebase & DEC or we might
* have them stuck.
*/
if (num_online_cpus() < 2) {
if (psurge_type == PSURGE_DUAL)
psurge_set_ipi(1);
return;
}
/* reset the entry point so if we get another intr we won't
* try to startup again */
out_be32(psurge_start, 0x100);
if (setup_irq(30, &psurge_irqaction))
printk(KERN_ERR "Couldn't get primary IPI interrupt");
}
if (psurge_type == PSURGE_DUAL)
psurge_dual_sync_tb(cpu_nr);
}
void __init smp_psurge_take_timebase(void)
{
/* Dummy implementation */
}
void __init smp_psurge_give_timebase(void)
{
/* Dummy implementation */
}
/* PowerSurge-style Macs */
struct smp_ops_t psurge_smp_ops = {
.message_pass = smp_psurge_message_pass,
.probe = smp_psurge_probe,
.kick_cpu = smp_psurge_kick_cpu,
.setup_cpu = smp_psurge_setup_cpu,
.give_timebase = smp_psurge_give_timebase,
.take_timebase = smp_psurge_take_timebase,
};
#endif /* CONFIG_PPC32 - actually powersurge support */
/*
* Core 99 and later support
*/
static void (*pmac_tb_freeze)(int freeze);
static u64 timebase;
static int tb_req;
static void smp_core99_give_timebase(void)
{
unsigned long flags;
local_irq_save(flags);
while(!tb_req)
barrier();
tb_req = 0;
(*pmac_tb_freeze)(1);
mb();
timebase = get_tb();
mb();
while (timebase)
barrier();
mb();
(*pmac_tb_freeze)(0);
mb();
local_irq_restore(flags);
}
static void __devinit smp_core99_take_timebase(void)
{
unsigned long flags;
local_irq_save(flags);
tb_req = 1;
mb();
while (!timebase)
barrier();
mb();
set_tb(timebase >> 32, timebase & 0xffffffff);
timebase = 0;
mb();
set_dec(tb_ticks_per_jiffy/2);
local_irq_restore(flags);
}
#ifdef CONFIG_PPC64
/*
* G5s enable/disable the timebase via an i2c-connected clock chip.
*/
static struct pmac_i2c_bus *pmac_tb_clock_chip_host;
static u8 pmac_tb_pulsar_addr;
static void smp_core99_cypress_tb_freeze(int freeze)
{
u8 data;
int rc;
/* Strangely, the device-tree says address is 0xd2, but darwin
* accesses 0xd0 ...
*/
pmac_i2c_setmode(pmac_tb_clock_chip_host,
pmac_i2c_mode_combined);
rc = pmac_i2c_xfer(pmac_tb_clock_chip_host,
0xd0 | pmac_i2c_read,
1, 0x81, &data, 1);
if (rc != 0)
goto bail;
data = (data & 0xf3) | (freeze ? 0x00 : 0x0c);
pmac_i2c_setmode(pmac_tb_clock_chip_host, pmac_i2c_mode_stdsub);
rc = pmac_i2c_xfer(pmac_tb_clock_chip_host,
0xd0 | pmac_i2c_write,
1, 0x81, &data, 1);
bail:
if (rc != 0) {
printk("Cypress Timebase %s rc: %d\n",
freeze ? "freeze" : "unfreeze", rc);
panic("Timebase freeze failed !\n");
}
}
static void smp_core99_pulsar_tb_freeze(int freeze)
{
u8 data;
int rc;
pmac_i2c_setmode(pmac_tb_clock_chip_host,
pmac_i2c_mode_combined);
rc = pmac_i2c_xfer(pmac_tb_clock_chip_host,
pmac_tb_pulsar_addr | pmac_i2c_read,
1, 0x2e, &data, 1);
if (rc != 0)
goto bail;
data = (data & 0x88) | (freeze ? 0x11 : 0x22);
pmac_i2c_setmode(pmac_tb_clock_chip_host, pmac_i2c_mode_stdsub);
rc = pmac_i2c_xfer(pmac_tb_clock_chip_host,
pmac_tb_pulsar_addr | pmac_i2c_write,
1, 0x2e, &data, 1);
bail:
if (rc != 0) {
printk(KERN_ERR "Pulsar Timebase %s rc: %d\n",
freeze ? "freeze" : "unfreeze", rc);
panic("Timebase freeze failed !\n");
}
}
static void __init smp_core99_setup_i2c_hwsync(int ncpus)
{
struct device_node *cc = NULL;
struct device_node *p;
const char *name = NULL;
const u32 *reg;
int ok;
/* Look for the clock chip */
while ((cc = of_find_node_by_name(cc, "i2c-hwclock")) != NULL) {
p = of_get_parent(cc);
ok = p && device_is_compatible(p, "uni-n-i2c");
of_node_put(p);
if (!ok)
continue;
pmac_tb_clock_chip_host = pmac_i2c_find_bus(cc);
if (pmac_tb_clock_chip_host == NULL)
continue;
reg = get_property(cc, "reg", NULL);
if (reg == NULL)
continue;
switch (*reg) {
case 0xd2:
if (device_is_compatible(cc,"pulsar-legacy-slewing")) {
pmac_tb_freeze = smp_core99_pulsar_tb_freeze;
pmac_tb_pulsar_addr = 0xd2;
name = "Pulsar";
} else if (device_is_compatible(cc, "cy28508")) {
pmac_tb_freeze = smp_core99_cypress_tb_freeze;
name = "Cypress";
}
break;
case 0xd4:
pmac_tb_freeze = smp_core99_pulsar_tb_freeze;
pmac_tb_pulsar_addr = 0xd4;
name = "Pulsar";
break;
}
if (pmac_tb_freeze != NULL)
break;
}
if (pmac_tb_freeze != NULL) {
/* Open i2c bus for synchronous access */
if (pmac_i2c_open(pmac_tb_clock_chip_host, 1)) {
printk(KERN_ERR "Failed top open i2c bus for clock"
" sync, fallback to software sync !\n");
goto no_i2c_sync;
}
printk(KERN_INFO "Processor timebase sync using %s i2c clock\n",
name);
return;
}
no_i2c_sync:
pmac_tb_freeze = NULL;
pmac_tb_clock_chip_host = NULL;
}
/*
* Newer G5s uses a platform function
*/
static void smp_core99_pfunc_tb_freeze(int freeze)
{
struct device_node *cpus;
struct pmf_args args;
cpus = of_find_node_by_path("/cpus");
BUG_ON(cpus == NULL);
args.count = 1;
args.u[0].v = !freeze;
pmf_call_function(cpus, "cpu-timebase", &args);
of_node_put(cpus);
}
#else /* CONFIG_PPC64 */
/*
* SMP G4 use a GPIO to enable/disable the timebase.
*/
static unsigned int core99_tb_gpio; /* Timebase freeze GPIO */
static void smp_core99_gpio_tb_freeze(int freeze)
{
if (freeze)
pmac_call_feature(PMAC_FTR_WRITE_GPIO, NULL, core99_tb_gpio, 4);
else
pmac_call_feature(PMAC_FTR_WRITE_GPIO, NULL, core99_tb_gpio, 0);
pmac_call_feature(PMAC_FTR_READ_GPIO, NULL, core99_tb_gpio, 0);
}
#endif /* !CONFIG_PPC64 */
/* L2 and L3 cache settings to pass from CPU0 to CPU1 on G4 cpus */
volatile static long int core99_l2_cache;
volatile static long int core99_l3_cache;
static void __devinit core99_init_caches(int cpu)
{
#ifndef CONFIG_PPC64
if (!cpu_has_feature(CPU_FTR_L2CR))
return;
if (cpu == 0) {
core99_l2_cache = _get_L2CR();
printk("CPU0: L2CR is %lx\n", core99_l2_cache);
} else {
printk("CPU%d: L2CR was %lx\n", cpu, _get_L2CR());
_set_L2CR(0);
_set_L2CR(core99_l2_cache);
printk("CPU%d: L2CR set to %lx\n", cpu, core99_l2_cache);
}
if (!cpu_has_feature(CPU_FTR_L3CR))
return;
if (cpu == 0){
core99_l3_cache = _get_L3CR();
printk("CPU0: L3CR is %lx\n", core99_l3_cache);
} else {
printk("CPU%d: L3CR was %lx\n", cpu, _get_L3CR());
_set_L3CR(0);
_set_L3CR(core99_l3_cache);
printk("CPU%d: L3CR set to %lx\n", cpu, core99_l3_cache);
}
#endif /* !CONFIG_PPC64 */
}
static void __init smp_core99_setup(int ncpus)
{
#ifdef CONFIG_PPC64
/* i2c based HW sync on some G5s */
if (machine_is_compatible("PowerMac7,2") ||
machine_is_compatible("PowerMac7,3") ||
machine_is_compatible("RackMac3,1"))
smp_core99_setup_i2c_hwsync(ncpus);
/* pfunc based HW sync on recent G5s */
if (pmac_tb_freeze == NULL) {
struct device_node *cpus =
of_find_node_by_path("/cpus");
if (cpus &&
get_property(cpus, "platform-cpu-timebase", NULL)) {
pmac_tb_freeze = smp_core99_pfunc_tb_freeze;
printk(KERN_INFO "Processor timebase sync using"
" platform function\n");
}
}
#else /* CONFIG_PPC64 */
/* GPIO based HW sync on ppc32 Core99 */
if (pmac_tb_freeze == NULL && !machine_is_compatible("MacRISC4")) {
struct device_node *cpu;
const u32 *tbprop = NULL;
core99_tb_gpio = KL_GPIO_TB_ENABLE; /* default value */
cpu = of_find_node_by_type(NULL, "cpu");
if (cpu != NULL) {
tbprop = get_property(cpu, "timebase-enable", NULL);
if (tbprop)
core99_tb_gpio = *tbprop;
of_node_put(cpu);
}
pmac_tb_freeze = smp_core99_gpio_tb_freeze;
printk(KERN_INFO "Processor timebase sync using"
" GPIO 0x%02x\n", core99_tb_gpio);
}
#endif /* CONFIG_PPC64 */
/* No timebase sync, fallback to software */
if (pmac_tb_freeze == NULL) {
smp_ops->give_timebase = smp_generic_give_timebase;
smp_ops->take_timebase = smp_generic_take_timebase;
printk(KERN_INFO "Processor timebase sync using software\n");
}
#ifndef CONFIG_PPC64
{
int i;
/* XXX should get this from reg properties */
for (i = 1; i < ncpus; ++i)
smp_hw_index[i] = i;
}
#endif
/* 32 bits SMP can't NAP */
if (!machine_is_compatible("MacRISC4"))
powersave_nap = 0;
}
static int __init smp_core99_probe(void)
{
struct device_node *cpus;
int ncpus = 0;
if (ppc_md.progress) ppc_md.progress("smp_core99_probe", 0x345);
/* Count CPUs in the device-tree */
for (cpus = NULL; (cpus = of_find_node_by_type(cpus, "cpu")) != NULL;)
++ncpus;
printk(KERN_INFO "PowerMac SMP probe found %d cpus\n", ncpus);
/* Nothing more to do if less than 2 of them */
if (ncpus <= 1)
return 1;
/* We need to perform some early initialisations before we can start
* setting up SMP as we are running before initcalls
*/
pmac_pfunc_base_install();
pmac_i2c_init();
/* Setup various bits like timebase sync method, ability to nap, ... */
smp_core99_setup(ncpus);
/* Install IPIs */
mpic_request_ipis();
/* Collect l2cr and l3cr values from CPU 0 */
core99_init_caches(0);
return ncpus;
}
static void __devinit smp_core99_kick_cpu(int nr)
{
unsigned int save_vector;
unsigned long target, flags;
volatile unsigned int *vector
= ((volatile unsigned int *)(KERNELBASE+0x100));
if (nr < 0 || nr > 3)
return;
if (ppc_md.progress)
ppc_md.progress("smp_core99_kick_cpu", 0x346);
local_irq_save(flags);
local_irq_disable();
/* Save reset vector */
save_vector = *vector;
/* Setup fake reset vector that does
* b __secondary_start_pmac_0 + nr*8 - KERNELBASE
*/
target = (unsigned long) __secondary_start_pmac_0 + nr * 8;
create_branch((unsigned long)vector, target, BRANCH_SET_LINK);
/* Put some life in our friend */
pmac_call_feature(PMAC_FTR_RESET_CPU, NULL, nr, 0);
/* FIXME: We wait a bit for the CPU to take the exception, I should
* instead wait for the entry code to set something for me. Well,
* ideally, all that crap will be done in prom.c and the CPU left
* in a RAM-based wait loop like CHRP.
*/
mdelay(1);
/* Restore our exception vector */
*vector = save_vector;
flush_icache_range((unsigned long) vector, (unsigned long) vector + 4);
local_irq_restore(flags);
if (ppc_md.progress) ppc_md.progress("smp_core99_kick_cpu done", 0x347);
}
static void __devinit smp_core99_setup_cpu(int cpu_nr)
{
/* Setup L2/L3 */
if (cpu_nr != 0)
core99_init_caches(cpu_nr);
/* Setup openpic */
mpic_setup_this_cpu();
if (cpu_nr == 0) {
#ifdef CONFIG_PPC64
extern void g5_phy_disable_cpu1(void);
/* Close i2c bus if it was used for tb sync */
if (pmac_tb_clock_chip_host) {
pmac_i2c_close(pmac_tb_clock_chip_host);
pmac_tb_clock_chip_host = NULL;
}
/* If we didn't start the second CPU, we must take
* it off the bus
*/
if (machine_is_compatible("MacRISC4") &&
num_online_cpus() < 2)
g5_phy_disable_cpu1();
#endif /* CONFIG_PPC64 */
if (ppc_md.progress)
ppc_md.progress("core99_setup_cpu 0 done", 0x349);
}
}
#if defined(CONFIG_HOTPLUG_CPU) && defined(CONFIG_PPC32)
int smp_core99_cpu_disable(void)
{
cpu_clear(smp_processor_id(), cpu_online_map);
/* XXX reset cpu affinity here */
mpic_cpu_set_priority(0xf);
asm volatile("mtdec %0" : : "r" (0x7fffffff));
mb();
udelay(20);
asm volatile("mtdec %0" : : "r" (0x7fffffff));
return 0;
}
extern void low_cpu_die(void) __attribute__((noreturn)); /* in sleep.S */
static int cpu_dead[NR_CPUS];
void cpu_die(void)
{
local_irq_disable();
cpu_dead[smp_processor_id()] = 1;
mb();
low_cpu_die();
}
void smp_core99_cpu_die(unsigned int cpu)
{
int timeout;
timeout = 1000;
while (!cpu_dead[cpu]) {
if (--timeout == 0) {
printk("CPU %u refused to die!\n", cpu);
break;
}
msleep(1);
}
cpu_dead[cpu] = 0;
}
#endif
/* Core99 Macs (dual G4s and G5s) */
struct smp_ops_t core99_smp_ops = {
.message_pass = smp_mpic_message_pass,
.probe = smp_core99_probe,
.kick_cpu = smp_core99_kick_cpu,
.setup_cpu = smp_core99_setup_cpu,
.give_timebase = smp_core99_give_timebase,
.take_timebase = smp_core99_take_timebase,
#if defined(CONFIG_HOTPLUG_CPU) && defined(CONFIG_PPC32)
.cpu_disable = smp_core99_cpu_disable,
.cpu_die = smp_core99_cpu_die,
#endif
};