linux/arch/ppc/platforms/pmac_smp.c
Paul Mackerras 6460b4cceb [PATCH] ppc32: improve timebase sync for SMP
Currently the procedure in the ppc32 kernel that synchronizes the timebase
registers across an SMP powermac system does so by setting both timebases
to zero.  That is OK at boot but causes problems if done later.  So that we
can do hotplug CPU on these machines, this patch changes the code so it
reads the timebase from one CPU and transfers the value to the other CPU. 
(Hotplug CPU is needed for sleep (aka suspend to RAM) to work.)

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-04-16 15:24:16 -07:00

671 lines
17 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/config.h>
#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 <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/residual.h>
#include <asm/machdep.h>
#include <asm/pmac_feature.h>
#include <asm/time.h>
#include <asm/open_pic.h>
#include <asm/cacheflush.h>
#include <asm/keylargo.h>
/*
* Powersurge (old powermac SMP) support.
*/
extern void __secondary_start_psurge(void);
extern void __secondary_start_psurge2(void); /* Temporary horrible hack */
extern void __secondary_start_psurge3(void); /* Temporary horrible hack */
/* 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 *hhead_base;
static volatile u8 *quad_base;
static volatile u32 *psurge_pri_intr;
static volatile u8 *psurge_sec_intr;
static volatile u32 *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;
/* L2 and L3 cache settings to pass from CPU0 to CPU1 */
volatile static long int core99_l2_cache;
volatile static long int core99_l3_cache;
/* Timebase freeze GPIO */
static unsigned int core99_tb_gpio;
/* Sync flag for HW tb sync */
static volatile int sec_tb_reset = 0;
static unsigned int pri_tb_hi, pri_tb_lo;
static unsigned int pri_tb_stamp;
static void __init core99_init_caches(int cpu)
{
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);
}
}
/*
* 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 __pmac psurge_smp_message_recv(struct pt_regs *regs)
{
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, regs);
}
irqreturn_t __pmac psurge_primary_intr(int irq, void *d, struct pt_regs *regs)
{
psurge_smp_message_recv(regs);
return IRQ_HANDLED;
}
static void __pmac smp_psurge_message_pass(int target, int msg, unsigned long data,
int wait)
{
int i;
if (num_online_cpus() < 2)
return;
for (i = 0; i < NR_CPUS; i++) {
if (!cpu_online(i))
continue;
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((void *) quad_base);
if ((in_8(hhead_base + HHEAD_CONFIG) & 0x02) == 0) {
/* not a dual-cpu card */
iounmap((void *) 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 not actually strictly necessary -- paulus. */
for (i = 1; i < ncpus; ++i)
smp_hw_index[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)
{
void (*start)(void) = __secondary_start_psurge;
unsigned long a;
/* 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);
/* setup entry point of secondary processor */
switch (nr) {
case 2:
start = __secondary_start_psurge2;
break;
case 3:
start = __secondary_start_psurge3;
break;
}
out_be32(psurge_start, __pa(start));
mb();
psurge_set_ipi(nr);
udelay(10);
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);
set_tb(0, 0);
last_jiffy_stamp(cpu_nr) = 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);
smp_tb_synchronized = 1;
}
static struct irqaction psurge_irqaction = {
.handler = psurge_primary_intr,
.flags = SA_INTERRUPT,
.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 */
}
static int __init smp_core99_probe(void)
{
#ifdef CONFIG_6xx
extern int powersave_nap;
#endif
struct device_node *cpus, *firstcpu;
int i, ncpus = 0, boot_cpu = -1;
u32 *tbprop = NULL;
if (ppc_md.progress) ppc_md.progress("smp_core99_probe", 0x345);
cpus = firstcpu = find_type_devices("cpu");
while(cpus != NULL) {
u32 *regprop = (u32 *)get_property(cpus, "reg", NULL);
char *stateprop = (char *)get_property(cpus, "state", NULL);
if (regprop != NULL && stateprop != NULL &&
!strncmp(stateprop, "running", 7))
boot_cpu = *regprop;
++ncpus;
cpus = cpus->next;
}
if (boot_cpu == -1)
printk(KERN_WARNING "Couldn't detect boot CPU !\n");
if (boot_cpu != 0)
printk(KERN_WARNING "Boot CPU is %d, unsupported setup !\n", boot_cpu);
if (machine_is_compatible("MacRISC4")) {
extern struct smp_ops_t core99_smp_ops;
core99_smp_ops.take_timebase = smp_generic_take_timebase;
core99_smp_ops.give_timebase = smp_generic_give_timebase;
} else {
if (firstcpu != NULL)
tbprop = (u32 *)get_property(firstcpu, "timebase-enable", NULL);
if (tbprop)
core99_tb_gpio = *tbprop;
else
core99_tb_gpio = KL_GPIO_TB_ENABLE;
}
if (ncpus > 1) {
openpic_request_IPIs();
for (i = 1; i < ncpus; ++i)
smp_hw_index[i] = i;
#ifdef CONFIG_6xx
powersave_nap = 0;
#endif
core99_init_caches(0);
}
return ncpus;
}
static void __init smp_core99_kick_cpu(int nr)
{
unsigned long save_vector, new_vector;
unsigned long flags;
volatile unsigned long *vector
= ((volatile unsigned long *)(KERNELBASE+0x100));
if (nr < 1 || 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_psurge - KERNELBASE
*/
switch(nr) {
case 1:
new_vector = (unsigned long)__secondary_start_psurge;
break;
case 2:
new_vector = (unsigned long)__secondary_start_psurge2;
break;
case 3:
new_vector = (unsigned long)__secondary_start_psurge3;
break;
}
*vector = 0x48000002 + new_vector - KERNELBASE;
/* flush data cache and inval instruction cache */
flush_icache_range((unsigned long) vector, (unsigned long) vector + 4);
/* 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 __init smp_core99_setup_cpu(int cpu_nr)
{
/* Setup L2/L3 */
if (cpu_nr != 0)
core99_init_caches(cpu_nr);
/* Setup openpic */
do_openpic_setup_cpu();
if (cpu_nr == 0) {
#ifdef CONFIG_POWER4
extern void g5_phy_disable_cpu1(void);
/* 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_POWER4 */
if (ppc_md.progress) ppc_md.progress("core99_setup_cpu 0 done", 0x349);
}
}
/* not __init, called in sleep/wakeup code */
void smp_core99_take_timebase(void)
{
unsigned long flags;
/* tell the primary we're here */
sec_tb_reset = 1;
mb();
/* wait for the primary to set pri_tb_hi/lo */
while (sec_tb_reset < 2)
mb();
/* set our stuff the same as the primary */
local_irq_save(flags);
set_dec(1);
set_tb(pri_tb_hi, pri_tb_lo);
last_jiffy_stamp(smp_processor_id()) = pri_tb_stamp;
mb();
/* tell the primary we're done */
sec_tb_reset = 0;
mb();
local_irq_restore(flags);
}
/* not __init, called in sleep/wakeup code */
void smp_core99_give_timebase(void)
{
unsigned long flags;
unsigned int t;
/* wait for the secondary to be in take_timebase */
for (t = 100000; t > 0 && !sec_tb_reset; --t)
udelay(10);
if (!sec_tb_reset) {
printk(KERN_WARNING "Timeout waiting sync on second CPU\n");
return;
}
/* freeze the timebase and read it */
/* disable interrupts so the timebase is disabled for the
shortest possible time */
local_irq_save(flags);
pmac_call_feature(PMAC_FTR_WRITE_GPIO, NULL, core99_tb_gpio, 4);
pmac_call_feature(PMAC_FTR_READ_GPIO, NULL, core99_tb_gpio, 0);
mb();
pri_tb_hi = get_tbu();
pri_tb_lo = get_tbl();
pri_tb_stamp = last_jiffy_stamp(smp_processor_id());
mb();
/* tell the secondary we're ready */
sec_tb_reset = 2;
mb();
/* wait for the secondary to have taken it */
for (t = 100000; t > 0 && sec_tb_reset; --t)
udelay(10);
if (sec_tb_reset)
printk(KERN_WARNING "Timeout waiting sync(2) on second CPU\n");
else
smp_tb_synchronized = 1;
/* Now, restart the timebase by leaving the GPIO to an open collector */
pmac_call_feature(PMAC_FTR_WRITE_GPIO, NULL, core99_tb_gpio, 0);
pmac_call_feature(PMAC_FTR_READ_GPIO, NULL, core99_tb_gpio, 0);
local_irq_restore(flags);
}
/* PowerSurge-style Macs */
struct smp_ops_t psurge_smp_ops __pmacdata = {
.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,
};
/* Core99 Macs (dual G4s) */
struct smp_ops_t core99_smp_ops __pmacdata = {
.message_pass = smp_openpic_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,
};