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-rw-r--r--arch/mips/kernel/Makefile3
-rw-r--r--arch/mips/kernel/cevt-r4k.c173
-rw-r--r--arch/mips/kernel/cevt-smtc.c321
-rw-r--r--arch/mips/kernel/cpu-probe.c28
-rw-r--r--arch/mips/kernel/entry.S10
-rw-r--r--arch/mips/kernel/genex.S45
-rw-r--r--arch/mips/kernel/head.S1
-rw-r--r--arch/mips/kernel/kgdb.c3
-rw-r--r--arch/mips/kernel/mips-mt-fpaff.c2
-rw-r--r--arch/mips/kernel/proc.c13
-rw-r--r--arch/mips/kernel/process.c19
-rw-r--r--arch/mips/kernel/ptrace.c102
-rw-r--r--arch/mips/kernel/ptrace32.c59
-rw-r--r--arch/mips/kernel/scall64-n32.S2
-rw-r--r--arch/mips/kernel/scall64-o32.S2
-rw-r--r--arch/mips/kernel/signal32.c12
-rw-r--r--arch/mips/kernel/smp.c2
-rw-r--r--arch/mips/kernel/smtc.c260
-rw-r--r--arch/mips/kernel/traps.c52
-rw-r--r--arch/mips/kernel/vmlinux.lds.S1
-rw-r--r--arch/mips/kernel/watch.c188
21 files changed, 953 insertions, 345 deletions
diff --git a/arch/mips/kernel/Makefile b/arch/mips/kernel/Makefile
index 706f9397479..d9da7112aaf 100644
--- a/arch/mips/kernel/Makefile
+++ b/arch/mips/kernel/Makefile
@@ -6,10 +6,11 @@ extra-y := head.o init_task.o vmlinux.lds
obj-y += cpu-probe.o branch.o entry.o genex.o irq.o process.o \
ptrace.o reset.o setup.o signal.o syscall.o \
- time.o topology.o traps.o unaligned.o
+ time.o topology.o traps.o unaligned.o watch.o
obj-$(CONFIG_CEVT_BCM1480) += cevt-bcm1480.o
obj-$(CONFIG_CEVT_R4K) += cevt-r4k.o
+obj-$(CONFIG_MIPS_MT_SMTC) += cevt-smtc.o
obj-$(CONFIG_CEVT_DS1287) += cevt-ds1287.o
obj-$(CONFIG_CEVT_GT641XX) += cevt-gt641xx.o
obj-$(CONFIG_CEVT_SB1250) += cevt-sb1250.o
diff --git a/arch/mips/kernel/cevt-r4k.c b/arch/mips/kernel/cevt-r4k.c
index 24a2d907aa0..4a4c59f2737 100644
--- a/arch/mips/kernel/cevt-r4k.c
+++ b/arch/mips/kernel/cevt-r4k.c
@@ -12,6 +12,14 @@
#include <asm/smtc_ipi.h>
#include <asm/time.h>
+#include <asm/cevt-r4k.h>
+
+/*
+ * The SMTC Kernel for the 34K, 1004K, et. al. replaces several
+ * of these routines with SMTC-specific variants.
+ */
+
+#ifndef CONFIG_MIPS_MT_SMTC
static int mips_next_event(unsigned long delta,
struct clock_event_device *evt)
@@ -19,60 +27,27 @@ static int mips_next_event(unsigned long delta,
unsigned int cnt;
int res;
-#ifdef CONFIG_MIPS_MT_SMTC
- {
- unsigned long flags, vpflags;
- local_irq_save(flags);
- vpflags = dvpe();
-#endif
cnt = read_c0_count();
cnt += delta;
write_c0_compare(cnt);
res = ((int)(read_c0_count() - cnt) > 0) ? -ETIME : 0;
-#ifdef CONFIG_MIPS_MT_SMTC
- evpe(vpflags);
- local_irq_restore(flags);
- }
-#endif
return res;
}
-static void mips_set_mode(enum clock_event_mode mode,
- struct clock_event_device *evt)
+#endif /* CONFIG_MIPS_MT_SMTC */
+
+void mips_set_clock_mode(enum clock_event_mode mode,
+ struct clock_event_device *evt)
{
/* Nothing to do ... */
}
-static DEFINE_PER_CPU(struct clock_event_device, mips_clockevent_device);
-static int cp0_timer_irq_installed;
+DEFINE_PER_CPU(struct clock_event_device, mips_clockevent_device);
+int cp0_timer_irq_installed;
-/*
- * Timer ack for an R4k-compatible timer of a known frequency.
- */
-static void c0_timer_ack(void)
-{
- write_c0_compare(read_c0_compare());
-}
+#ifndef CONFIG_MIPS_MT_SMTC
-/*
- * Possibly handle a performance counter interrupt.
- * Return true if the timer interrupt should not be checked
- */
-static inline int handle_perf_irq(int r2)
-{
- /*
- * The performance counter overflow interrupt may be shared with the
- * timer interrupt (cp0_perfcount_irq < 0). If it is and a
- * performance counter has overflowed (perf_irq() == IRQ_HANDLED)
- * and we can't reliably determine if a counter interrupt has also
- * happened (!r2) then don't check for a timer interrupt.
- */
- return (cp0_perfcount_irq < 0) &&
- perf_irq() == IRQ_HANDLED &&
- !r2;
-}
-
-static irqreturn_t c0_compare_interrupt(int irq, void *dev_id)
+irqreturn_t c0_compare_interrupt(int irq, void *dev_id)
{
const int r2 = cpu_has_mips_r2;
struct clock_event_device *cd;
@@ -93,12 +68,8 @@ static irqreturn_t c0_compare_interrupt(int irq, void *dev_id)
* interrupt. Being the paranoiacs we are we check anyway.
*/
if (!r2 || (read_c0_cause() & (1 << 30))) {
- c0_timer_ack();
-#ifdef CONFIG_MIPS_MT_SMTC
- if (cpu_data[cpu].vpe_id)
- goto out;
- cpu = 0;
-#endif
+ /* Clear Count/Compare Interrupt */
+ write_c0_compare(read_c0_compare());
cd = &per_cpu(mips_clockevent_device, cpu);
cd->event_handler(cd);
}
@@ -107,65 +78,16 @@ out:
return IRQ_HANDLED;
}
-static struct irqaction c0_compare_irqaction = {
+#endif /* Not CONFIG_MIPS_MT_SMTC */
+
+struct irqaction c0_compare_irqaction = {
.handler = c0_compare_interrupt,
-#ifdef CONFIG_MIPS_MT_SMTC
- .flags = IRQF_DISABLED,
-#else
.flags = IRQF_DISABLED | IRQF_PERCPU,
-#endif
.name = "timer",
};
-#ifdef CONFIG_MIPS_MT_SMTC
-DEFINE_PER_CPU(struct clock_event_device, smtc_dummy_clockevent_device);
-
-static void smtc_set_mode(enum clock_event_mode mode,
- struct clock_event_device *evt)
-{
-}
-
-static void mips_broadcast(cpumask_t mask)
-{
- unsigned int cpu;
-
- for_each_cpu_mask(cpu, mask)
- smtc_send_ipi(cpu, SMTC_CLOCK_TICK, 0);
-}
-
-static void setup_smtc_dummy_clockevent_device(void)
-{
- //uint64_t mips_freq = mips_hpt_^frequency;
- unsigned int cpu = smp_processor_id();
- struct clock_event_device *cd;
- cd = &per_cpu(smtc_dummy_clockevent_device, cpu);
-
- cd->name = "SMTC";
- cd->features = CLOCK_EVT_FEAT_DUMMY;
-
- /* Calculate the min / max delta */
- cd->mult = 0; //div_sc((unsigned long) mips_freq, NSEC_PER_SEC, 32);
- cd->shift = 0; //32;
- cd->max_delta_ns = 0; //clockevent_delta2ns(0x7fffffff, cd);
- cd->min_delta_ns = 0; //clockevent_delta2ns(0x30, cd);
-
- cd->rating = 200;
- cd->irq = 17; //-1;
-// if (cpu)
-// cd->cpumask = CPU_MASK_ALL; // cpumask_of_cpu(cpu);
-// else
- cd->cpumask = cpumask_of_cpu(cpu);
-
- cd->set_mode = smtc_set_mode;
-
- cd->broadcast = mips_broadcast;
-
- clockevents_register_device(cd);
-}
-#endif
-
-static void mips_event_handler(struct clock_event_device *dev)
+void mips_event_handler(struct clock_event_device *dev)
{
}
@@ -177,7 +99,23 @@ static int c0_compare_int_pending(void)
return (read_c0_cause() >> cp0_compare_irq) & 0x100;
}
-static int c0_compare_int_usable(void)
+/*
+ * Compare interrupt can be routed and latched outside the core,
+ * so a single execution hazard barrier may not be enough to give
+ * it time to clear as seen in the Cause register. 4 time the
+ * pipeline depth seems reasonably conservative, and empirically
+ * works better in configurations with high CPU/bus clock ratios.
+ */
+
+#define compare_change_hazard() \
+ do { \
+ irq_disable_hazard(); \
+ irq_disable_hazard(); \
+ irq_disable_hazard(); \
+ irq_disable_hazard(); \
+ } while (0)
+
+int c0_compare_int_usable(void)
{
unsigned int delta;
unsigned int cnt;
@@ -187,7 +125,7 @@ static int c0_compare_int_usable(void)
*/
if (c0_compare_int_pending()) {
write_c0_compare(read_c0_count());
- irq_disable_hazard();
+ compare_change_hazard();
if (c0_compare_int_pending())
return 0;
}
@@ -196,7 +134,7 @@ static int c0_compare_int_usable(void)
cnt = read_c0_count();
cnt += delta;
write_c0_compare(cnt);
- irq_disable_hazard();
+ compare_change_hazard();
if ((int)(read_c0_count() - cnt) < 0)
break;
/* increase delta if the timer was already expired */
@@ -205,11 +143,12 @@ static int c0_compare_int_usable(void)
while ((int)(read_c0_count() - cnt) <= 0)
; /* Wait for expiry */
+ compare_change_hazard();
if (!c0_compare_int_pending())
return 0;
write_c0_compare(read_c0_count());
- irq_disable_hazard();
+ compare_change_hazard();
if (c0_compare_int_pending())
return 0;
@@ -219,6 +158,8 @@ static int c0_compare_int_usable(void)
return 1;
}
+#ifndef CONFIG_MIPS_MT_SMTC
+
int __cpuinit mips_clockevent_init(void)
{
uint64_t mips_freq = mips_hpt_frequency;
@@ -229,17 +170,6 @@ int __cpuinit mips_clockevent_init(void)
if (!cpu_has_counter || !mips_hpt_frequency)
return -ENXIO;
-#ifdef CONFIG_MIPS_MT_SMTC
- setup_smtc_dummy_clockevent_device();
-
- /*
- * On SMTC we only register VPE0's compare interrupt as clockevent
- * device.
- */
- if (cpu)
- return 0;
-#endif
-
if (!c0_compare_int_usable())
return -ENXIO;
@@ -265,13 +195,9 @@ int __cpuinit mips_clockevent_init(void)
cd->rating = 300;
cd->irq = irq;
-#ifdef CONFIG_MIPS_MT_SMTC
- cd->cpumask = CPU_MASK_ALL;
-#else
cd->cpumask = cpumask_of_cpu(cpu);
-#endif
cd->set_next_event = mips_next_event;
- cd->set_mode = mips_set_mode;
+ cd->set_mode = mips_set_clock_mode;
cd->event_handler = mips_event_handler;
clockevents_register_device(cd);
@@ -281,12 +207,9 @@ int __cpuinit mips_clockevent_init(void)
cp0_timer_irq_installed = 1;
-#ifdef CONFIG_MIPS_MT_SMTC
-#define CPUCTR_IMASKBIT (0x100 << cp0_compare_irq)
- setup_irq_smtc(irq, &c0_compare_irqaction, CPUCTR_IMASKBIT);
-#else
setup_irq(irq, &c0_compare_irqaction);
-#endif
return 0;
}
+
+#endif /* Not CONFIG_MIPS_MT_SMTC */
diff --git a/arch/mips/kernel/cevt-smtc.c b/arch/mips/kernel/cevt-smtc.c
new file mode 100644
index 00000000000..5162fe4b595
--- /dev/null
+++ b/arch/mips/kernel/cevt-smtc.c
@@ -0,0 +1,321 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2007 MIPS Technologies, Inc.
+ * Copyright (C) 2007 Ralf Baechle <ralf@linux-mips.org>
+ * Copyright (C) 2008 Kevin D. Kissell, Paralogos sarl
+ */
+#include <linux/clockchips.h>
+#include <linux/interrupt.h>
+#include <linux/percpu.h>
+
+#include <asm/smtc_ipi.h>
+#include <asm/time.h>
+#include <asm/cevt-r4k.h>
+
+/*
+ * Variant clock event timer support for SMTC on MIPS 34K, 1004K
+ * or other MIPS MT cores.
+ *
+ * Notes on SMTC Support:
+ *
+ * SMTC has multiple microthread TCs pretending to be Linux CPUs.
+ * But there's only one Count/Compare pair per VPE, and Compare
+ * interrupts are taken opportunisitically by available TCs
+ * bound to the VPE with the Count register. The new timer
+ * framework provides for global broadcasts, but we really
+ * want VPE-level multicasts for best behavior. So instead
+ * of invoking the high-level clock-event broadcast code,
+ * this version of SMTC support uses the historical SMTC
+ * multicast mechanisms "under the hood", appearing to the
+ * generic clock layer as if the interrupts are per-CPU.
+ *
+ * The approach taken here is to maintain a set of NR_CPUS
+ * virtual timers, and track which "CPU" needs to be alerted
+ * at each event.
+ *
+ * It's unlikely that we'll see a MIPS MT core with more than
+ * 2 VPEs, but we *know* that we won't need to handle more
+ * VPEs than we have "CPUs". So NCPUs arrays of NCPUs elements
+ * is always going to be overkill, but always going to be enough.
+ */
+
+unsigned long smtc_nexttime[NR_CPUS][NR_CPUS];
+static int smtc_nextinvpe[NR_CPUS];
+
+/*
+ * Timestamps stored are absolute values to be programmed
+ * into Count register. Valid timestamps will never be zero.
+ * If a Zero Count value is actually calculated, it is converted
+ * to be a 1, which will introduce 1 or two CPU cycles of error
+ * roughly once every four billion events, which at 1000 HZ means
+ * about once every 50 days. If that's actually a problem, one
+ * could alternate squashing 0 to 1 and to -1.
+ */
+
+#define MAKEVALID(x) (((x) == 0L) ? 1L : (x))
+#define ISVALID(x) ((x) != 0L)
+
+/*
+ * Time comparison is subtle, as it's really truncated
+ * modular arithmetic.
+ */
+
+#define IS_SOONER(a, b, reference) \
+ (((a) - (unsigned long)(reference)) < ((b) - (unsigned long)(reference)))
+
+/*
+ * CATCHUP_INCREMENT, used when the function falls behind the counter.
+ * Could be an increasing function instead of a constant;
+ */
+
+#define CATCHUP_INCREMENT 64
+
+static int mips_next_event(unsigned long delta,
+ struct clock_event_device *evt)
+{
+ unsigned long flags;
+ unsigned int mtflags;
+ unsigned long timestamp, reference, previous;
+ unsigned long nextcomp = 0L;
+ int vpe = current_cpu_data.vpe_id;
+ int cpu = smp_processor_id();
+ local_irq_save(flags);
+ mtflags = dmt();
+
+ /*
+ * Maintain the per-TC virtual timer
+ * and program the per-VPE shared Count register
+ * as appropriate here...
+ */
+ reference = (unsigned long)read_c0_count();
+ timestamp = MAKEVALID(reference + delta);
+ /*
+ * To really model the clock, we have to catch the case
+ * where the current next-in-VPE timestamp is the old
+ * timestamp for the calling CPE, but the new value is
+ * in fact later. In that case, we have to do a full
+ * scan and discover the new next-in-VPE CPU id and
+ * timestamp.
+ */
+ previous = smtc_nexttime[vpe][cpu];
+ if (cpu == smtc_nextinvpe[vpe] && ISVALID(previous)
+ && IS_SOONER(previous, timestamp, reference)) {
+ int i;
+ int soonest = cpu;
+
+ /*
+ * Update timestamp array here, so that new
+ * value gets considered along with those of
+ * other virtual CPUs on the VPE.
+ */
+ smtc_nexttime[vpe][cpu] = timestamp;
+ for_each_online_cpu(i) {
+ if (ISVALID(smtc_nexttime[vpe][i])
+ && IS_SOONER(smtc_nexttime[vpe][i],
+ smtc_nexttime[vpe][soonest], reference)) {
+ soonest = i;
+ }
+ }
+ smtc_nextinvpe[vpe] = soonest;
+ nextcomp = smtc_nexttime[vpe][soonest];
+ /*
+ * Otherwise, we don't have to process the whole array rank,
+ * we just have to see if the event horizon has gotten closer.
+ */
+ } else {
+ if (!ISVALID(smtc_nexttime[vpe][smtc_nextinvpe[vpe]]) ||
+ IS_SOONER(timestamp,
+ smtc_nexttime[vpe][smtc_nextinvpe[vpe]], reference)) {
+ smtc_nextinvpe[vpe] = cpu;
+ nextcomp = timestamp;
+ }
+ /*
+ * Since next-in-VPE may me the same as the executing
+ * virtual CPU, we update the array *after* checking
+ * its value.
+ */
+ smtc_nexttime[vpe][cpu] = timestamp;
+ }
+
+ /*
+ * It may be that, in fact, we don't need to update Compare,
+ * but if we do, we want to make sure we didn't fall into
+ * a crack just behind Count.
+ */
+ if (ISVALID(nextcomp)) {
+ write_c0_compare(nextcomp);
+ ehb();
+ /*
+ * We never return an error, we just make sure
+ * that we trigger the handlers as quickly as
+ * we can if we fell behind.
+ */
+ while ((nextcomp - (unsigned long)read_c0_count())
+ > (unsigned long)LONG_MAX) {
+ nextcomp += CATCHUP_INCREMENT;
+ write_c0_compare(nextcomp);
+ ehb();
+ }
+ }
+ emt(mtflags);
+ local_irq_restore(flags);
+ return 0;
+}
+
+
+void smtc_distribute_timer(int vpe)
+{
+ unsigned long flags;
+ unsigned int mtflags;
+ int cpu;
+ struct clock_event_device *cd;
+ unsigned long nextstamp = 0L;
+ unsigned long reference;
+
+
+repeat:
+ for_each_online_cpu(cpu) {
+ /*
+ * Find virtual CPUs within the current VPE who have
+ * unserviced timer requests whose time is now past.
+ */
+ local_irq_save(flags);
+ mtflags = dmt();
+ if (cpu_data[cpu].vpe_id == vpe &&
+ ISVALID(smtc_nexttime[vpe][cpu])) {
+ reference = (unsigned long)read_c0_count();
+ if ((smtc_nexttime[vpe][cpu] - reference)
+ > (unsigned long)LONG_MAX) {
+ smtc_nexttime[vpe][cpu] = 0L;
+ emt(mtflags);
+ local_irq_restore(flags);
+ /*
+ * We don't send IPIs to ourself.
+ */
+ if (cpu != smp_processor_id()) {
+ smtc_send_ipi(cpu, SMTC_CLOCK_TICK, 0);
+ } else {
+ cd = &per_cpu(mips_clockevent_device, cpu);
+ cd->event_handler(cd);
+ }
+ } else {
+ /* Local to VPE but Valid Time not yet reached. */
+ if (!ISVALID(nextstamp) ||
+ IS_SOONER(smtc_nexttime[vpe][cpu], nextstamp,
+ reference)) {
+ smtc_nextinvpe[vpe] = cpu;
+ nextstamp = smtc_nexttime[vpe][cpu];
+ }
+ emt(mtflags);
+ local_irq_restore(flags);
+ }
+ } else {
+ emt(mtflags);
+ local_irq_restore(flags);
+
+ }
+ }
+ /* Reprogram for interrupt at next soonest timestamp for VPE */
+ if (ISVALID(nextstamp)) {
+ write_c0_compare(nextstamp);
+ ehb();
+ if ((nextstamp - (unsigned long)read_c0_count())
+ > (unsigned long)LONG_MAX)
+ goto repeat;
+ }
+}
+
+
+irqreturn_t c0_compare_interrupt(int irq, void *dev_id)
+{
+ int cpu = smp_processor_id();
+
+ /* If we're running SMTC, we've got MIPS MT and therefore MIPS32R2 */
+ handle_perf_irq(1);
+
+ if (read_c0_cause() & (1 << 30)) {
+ /* Clear Count/Compare Interrupt */
+ write_c0_compare(read_c0_compare());
+ smtc_distribute_timer(cpu_data[cpu].vpe_id);
+ }
+ return IRQ_HANDLED;
+}
+
+
+int __cpuinit mips_clockevent_init(void)
+{
+ uint64_t mips_freq = mips_hpt_frequency;
+ unsigned int cpu = smp_processor_id();
+ struct clock_event_device *cd;
+ unsigned int irq;
+ int i;
+ int j;
+
+ if (!cpu_has_counter || !mips_hpt_frequency)
+ return -ENXIO;
+ if (cpu == 0) {
+ for (i = 0; i < num_possible_cpus(); i++) {
+ smtc_nextinvpe[i] = 0;
+ for (j = 0; j < num_possible_cpus(); j++)
+ smtc_nexttime[i][j] = 0L;
+ }
+ /*
+ * SMTC also can't have the usablility test
+ * run by secondary TCs once Compare is in use.
+ */
+ if (!c0_compare_int_usable())
+ return -ENXIO;
+ }
+
+ /*
+ * With vectored interrupts things are getting platform specific.
+ * get_c0_compare_int is a hook to allow a platform to return the
+ * interrupt number of it's liking.
+ */
+ irq = MIPS_CPU_IRQ_BASE + cp0_compare_irq;
+ if (get_c0_compare_int)
+ irq = get_c0_compare_int();
+
+ cd = &per_cpu(mips_clockevent_device, cpu);
+
+ cd->name = "MIPS";
+ cd->features = CLOCK_EVT_FEAT_ONESHOT;
+
+ /* Calculate the min / max delta */
+ cd->mult = div_sc((unsigned long) mips_freq, NSEC_PER_SEC, 32);
+ cd->shift = 32;
+ cd->max_delta_ns = clockevent_delta2ns(0x7fffffff, cd);
+ cd->min_delta_ns = clockevent_delta2ns(0x300, cd);
+
+ cd->rating = 300;
+ cd->irq = irq;
+ cd->cpumask = cpumask_of_cpu(cpu);
+ cd->set_next_event = mips_next_event;
+ cd->set_mode = mips_set_clock_mode;
+ cd->event_handler = mips_event_handler;
+
+ clockevents_register_device(cd);
+
+ /*
+ * On SMTC we only want to do the data structure
+ * initialization and IRQ setup once.
+ */
+ if (cpu)
+ return 0;
+ /*
+ * And we need the hwmask associated with the c0_compare
+ * vector to be initialized.
+ */
+ irq_hwmask[irq] = (0x100 << cp0_compare_irq);
+ if (cp0_timer_irq_installed)
+ return 0;
+
+ cp0_timer_irq_installed = 1;
+
+ setup_irq(irq, &c0_compare_irqaction);
+
+ return 0;
+}
diff --git a/arch/mips/kernel/cpu-probe.c b/arch/mips/kernel/cpu-probe.c
index 335a6ae3d59..0cf15457eca 100644
--- a/arch/mips/kernel/cpu-probe.c
+++ b/arch/mips/kernel/cpu-probe.c
@@ -21,6 +21,7 @@
#include <asm/fpu.h>
#include <asm/mipsregs.h>
#include <asm/system.h>
+#include <asm/watch.h>
/*
* Not all of the MIPS CPUs have the "wait" instruction available. Moreover,
@@ -45,18 +46,7 @@ static void r39xx_wait(void)
local_irq_enable();
}
-/*
- * There is a race when WAIT instruction executed with interrupt
- * enabled.
- * But it is implementation-dependent wheter the pipelie restarts when
- * a non-enabled interrupt is requested.
- */
-static void r4k_wait(void)
-{
- __asm__(" .set mips3 \n"
- " wait \n"
- " .set mips0 \n");
-}
+extern void r4k_wait(void);
/*
* This variant is preferable as it allows testing need_resched and going to
@@ -65,14 +55,18 @@ static void r4k_wait(void)
* interrupt is requested" restriction in the MIPS32/MIPS64 architecture makes
* using this version a gamble.
*/
-static void r4k_wait_irqoff(void)
+void r4k_wait_irqoff(void)
{
local_irq_disable();
if (!need_resched())
- __asm__(" .set mips3 \n"
+ __asm__(" .set push \n"
+ " .set mips3 \n"
" wait \n"
- " .set mips0 \n");
+ " .set pop \n");
local_irq_enable();
+ __asm__(" .globl __pastwait \n"
+ "__pastwait: \n");
+ return;
}
/*
@@ -128,7 +122,7 @@ static int __init wait_disable(char *s)
__setup("nowait", wait_disable);
-static inline void check_wait(void)
+void __init check_wait(void)
{
struct cpuinfo_mips *c = &current_cpu_data;
@@ -242,7 +236,6 @@ static inline void check_errata(void)
void __init check_bugs32(void)
{
- check_wait();
check_errata();
}
@@ -685,6 +678,7 @@ static inline void spram_config(void) {}
static inline void cpu_probe_mips(struct cpuinfo_mips *c)
{
decode_configs(c);
+ mips_probe_watch_registers(c);
switch (c->processor_id & 0xff00) {
case PRID_IMP_4KC:
c->cputype = CPU_4KC;
diff --git a/arch/mips/kernel/entry.S b/arch/mips/kernel/entry.S
index e29598ae939..ffa331029e0 100644
--- a/arch/mips/kernel/entry.S
+++ b/arch/mips/kernel/entry.S
@@ -79,11 +79,6 @@ FEXPORT(syscall_exit)
FEXPORT(restore_all) # restore full frame
#ifdef CONFIG_MIPS_MT_SMTC
-/* Detect and execute deferred IPI "interrupts" */
- LONG_L s0, TI_REGS($28)
- LONG_S sp, TI_REGS($28)
- jal deferred_smtc_ipi
- LONG_S s0, TI_REGS($28)
#ifdef CONFIG_MIPS_MT_SMTC_IM_BACKSTOP
/* Re-arm any temporarily masked interrupts not explicitly "acked" */
mfc0 v0, CP0_TCSTATUS
@@ -112,6 +107,11 @@ FEXPORT(restore_all) # restore full frame
xor t0, t0, t3
mtc0 t0, CP0_TCCONTEXT
#endif /* CONFIG_MIPS_MT_SMTC_IM_BACKSTOP */
+/* Detect and execute deferred IPI "interrupts" */
+ LONG_L s0, TI_REGS($28)
+ LONG_S sp, TI_REGS($28)
+ jal deferred_smtc_ipi
+ LONG_S s0, TI_REGS($28)
#endif /* CONFIG_MIPS_MT_SMTC */
.set noat
RESTORE_TEMP
diff --git a/arch/mips/kernel/genex.S b/arch/mips/kernel/genex.S
index c6ada98ee04..757d48f0d80 100644
--- a/arch/mips/kernel/genex.S
+++ b/arch/mips/kernel/genex.S
@@ -20,6 +20,7 @@
#include <asm/stackframe.h>
#include <asm/war.h>
#include <asm/page.h>
+#include <asm/thread_info.h>
#define PANIC_PIC(msg) \
.set push; \
@@ -126,7 +127,42 @@ handle_vcei:
__FINIT
+ .align 5 /* 32 byte rollback region */
+LEAF(r4k_wait)
+ .set push
+ .set noreorder
+ /* start of rollback region */
+ LONG_L t0, TI_FLAGS($28)
+ nop
+ andi t0, _TIF_NEED_RESCHED
+ bnez t0, 1f
+ nop
+ nop
+ nop
+ .set mips3
+ wait
+ /* end of rollback region (the region size must be power of two) */
+ .set pop
+1:
+ jr ra
+ END(r4k_wait)
+
+ .macro BUILD_ROLLBACK_PROLOGUE handler
+ FEXPORT(rollback_\handler)
+ .set push
+ .set noat
+ MFC0 k0, CP0_EPC
+ PTR_LA k1, r4k_wait
+ ori k0, 0x1f /* 32 byte rollback region */
+ xori k0, 0x1f
+ bne k0, k1, 9f
+ MTC0 k0, CP0_EPC
+9:
+ .set pop
+ .endm
+
.align 5
+BUILD_ROLLBACK_PROLOGUE handle_int
NESTED(handle_int, PT_SIZE, sp)
#ifdef CONFIG_TRACE_IRQFLAGS
/*
@@ -201,6 +237,7 @@ NESTED(except_vec_ejtag_debug, 0, sp)
* This prototype is copied to ebase + n*IntCtl.VS and patched
* to invoke the handler
*/
+BUILD_ROLLBACK_PROLOGUE except_vec_vi
NESTED(except_vec_vi, 0, sp)
SAVE_SOME
SAVE_AT
@@ -245,8 +282,8 @@ NESTED(except_vec_vi_handler, 0, sp)
and t0, a0, t1
#ifdef CONFIG_MIPS_MT_SMTC_IM_BACKSTOP
mfc0 t2, CP0_TCCONTEXT
- or t0, t0, t2
- mtc0 t0, CP0_TCCONTEXT
+ or t2, t0, t2
+ mtc0 t2, CP0_TCCONTEXT
#endif /* CONFIG_MIPS_MT_SMTC_IM_BACKSTOP */
xor t1, t1, t0
mtc0 t1, CP0_STATUS
@@ -416,7 +453,11 @@ NESTED(nmi_handler, PT_SIZE, sp)
BUILD_HANDLER tr tr sti silent /* #13 */
BUILD_HANDLER fpe fpe fpe silent /* #15 */
BUILD_HANDLER mdmx mdmx sti silent /* #22 */
+#ifdef CONFIG_HARDWARE_WATCHPOINTS
+ BUILD_HANDLER watch watch sti silent /* #23 */
+#else
BUILD_HANDLER watch watch sti verbose /* #23 */
+#endif
BUILD_HANDLER mcheck mcheck cli verbose /* #24 */
BUILD_HANDLER mt mt sti silent /* #25 */
BUILD_HANDLER dsp dsp sti silent /* #26 */
diff --git a/arch/mips/kernel/head.S b/arch/mips/kernel/head.S
index 361364501d3..492a0a8d70f 100644
--- a/arch/mips/kernel/head.S
+++ b/arch/mips/kernel/head.S
@@ -22,6 +22,7 @@
#include <asm/irqflags.h>
#include <asm/regdef.h>
#include <asm/page.h>
+#include <asm/pgtable-bits.h>
#include <asm/mipsregs.h>
#include <asm/stackframe.h>
diff --git a/arch/mips/kernel/kgdb.c b/arch/mips/kernel/kgdb.c
index 8f6d58ede33..6e152c80cd4 100644
--- a/arch/mips/kernel/kgdb.c
+++ b/arch/mips/kernel/kgdb.c
@@ -236,8 +236,7 @@ int kgdb_arch_handle_exception(int vector, int signo, int err_code,
atomic_set(&kgdb_cpu_doing_single_step, -1);
if (remcom_in_buffer[0] == 's')
- if (kgdb_contthread)
- atomic_set(&kgdb_cpu_doing_single_step, cpu);
+ atomic_set(&kgdb_cpu_doing_single_step, cpu);
return 0;
}
diff --git a/arch/mips/kernel/mips-mt-fpaff.c b/arch/mips/kernel/mips-mt-fpaff.c
index df4d3f2f740..dc9eb72ed9d 100644
--- a/arch/mips/kernel/mips-mt-fpaff.c
+++ b/arch/mips/kernel/mips-mt-fpaff.c
@@ -159,7 +159,7 @@ __setup("fpaff=", fpaff_thresh);
/*
* FPU Use Factor empirically derived from experiments on 34K
*/
-#define FPUSEFACTOR 333
+#define FPUSEFACTOR 2000
static __init int mt_fp_affinity_init(void)
{
diff --git a/arch/mips/kernel/proc.c b/arch/mips/kernel/proc.c
index 36f06539824..75bb1300dd7 100644
--- a/arch/mips/kernel/proc.c
+++ b/arch/mips/kernel/proc.c
@@ -23,6 +23,7 @@ static int show_cpuinfo(struct seq_file *m, void *v)
unsigned int version = cpu_data[n].processor_id;
unsigned int fp_vers = cpu_data[n].fpu_id;
char fmt [64];
+ int i;
#ifdef CONFIG_SMP
if (!cpu_isset(n, cpu_online_map))
@@ -50,8 +51,16 @@ static int show_cpuinfo(struct seq_file *m, void *v)
seq_printf(m, "tlb_entries\t\t: %d\n", cpu_data[n].tlbsize);
seq_printf(m, "extra interrupt vector\t: %s\n",
cpu_has_divec ? "yes" : "no");
- seq_printf(m, "hardware watchpoint\t: %s\n",
- cpu_has_watch ? "yes" : "no");
+ seq_printf(m, "hardware watchpoint\t: %s",
+ cpu_has_watch ? "yes, " : "no\n");
+ if (cpu_has_watch) {
+ seq_printf(m, "count: %d, address/irw mask: [",
+ cpu_data[n].watch_reg_count);
+ for (i = 0; i < cpu_data[n].watch_reg_count; i++)
+ seq_printf(m, "%s0x%04x", i ? ", " : "" ,
+ cpu_data[n].watch_reg_masks[i]);
+ seq_printf(m, "]\n");
+ }
seq_printf(m, "ASEs implemented\t:%s%s%s%s%s%s\n",
cpu_has_mips16 ? " mips16" : "",
cpu_has_mdmx ? " mdmx" : "",
diff --git a/arch/mips/kernel/process.c b/arch/mips/kernel/process.c
index b16facd9ea8..22fc19bbe87 100644
--- a/arch/mips/kernel/process.c
+++ b/arch/mips/kernel/process.c
@@ -55,7 +55,7 @@ void __noreturn cpu_idle(void)
while (1) {
tick_nohz_stop_sched_tick(1);
while (!need_resched()) {
-#ifdef CONFIG_SMTC_IDLE_HOOK_DEBUG
+#ifdef CONFIG_MIPS_MT_SMTC
extern void smtc_idle_loop_hook(void);
smtc_idle_loop_hook();
@@ -145,17 +145,18 @@ int copy_thread(int nr, unsigned long clone_flags, unsigned long usp,
*/
p->thread.cp0_status = read_c0_status() & ~(ST0_CU2|ST0_CU1);
childregs->cp0_status &= ~(ST0_CU2|ST0_CU1);
- clear_tsk_thread_flag(p, TIF_USEDFPU);
-#ifdef CONFIG_MIPS_MT_FPAFF
+#ifdef CONFIG_MIPS_MT_SMTC
/*
- * FPU affinity support is cleaner if we track the
- * user-visible CPU affinity from the very beginning.
- * The generic cpus_allowed mask will already have
- * been copied from the parent before copy_thread
- * is invoked.
+ * SMTC restores TCStatus after Status, and the CU bits
+ * are aliased there.
*/
- p->thread.user_cpus_allowed = p->cpus_allowed;
+ childregs->cp0_tcstatus &= ~(ST0_CU2|ST0_CU1);
+#endif
+ clear_tsk_thread_flag(p, TIF_USEDFPU);
+
+#ifdef CONFIG_MIPS_MT_FPAFF
+ clear_tsk_thread_flag(p, TIF_FPUBOUND);
#endif /* CONFIG_MIPS_MT_FPAFF */
if (clone_flags & CLONE_SETTLS)
diff --git a/arch/mips/kernel/ptrace.c b/arch/mips/kernel/ptrace.c
index 35234b92b9a..054861ccb4d 100644
--- a/arch/mips/kernel/ptrace.c
+++ b/arch/mips/kernel/ptrace.c
@@ -46,7 +46,8 @@
*/
void ptrace_disable(struct task_struct *child)
{
- /* Nothing to do.. */
+ /* Don't load the watchpoint registers for the ex-child. */
+ clear_tsk_thread_flag(child, TIF_LOAD_WATCH);
}
/*
@@ -167,6 +168,93 @@ int ptrace_setfpregs(struct task_struct *child, __u32 __user *data)
return 0;
}
+int ptrace_get_watch_regs(struct task_struct *child,
+ struct pt_watch_regs __user *addr)
+{
+ enum pt_watch_style style;
+ int i;
+
+ if (!cpu_has_watch || current_cpu_data.watch_reg_use_cnt == 0)
+ return -EIO;
+ if (!access_ok(VERIFY_WRITE, addr, sizeof(struct pt_watch_regs)))
+ return -EIO;
+
+#ifdef CONFIG_32BIT
+ style = pt_watch_style_mips32;
+#define WATCH_STYLE mips32
+#else
+ style = pt_watch_style_mips64;
+#define WATCH_STYLE mips64
+#endif
+
+ __put_user(style, &addr->style);
+ __put_user(current_cpu_data.watch_reg_use_cnt,
+ &addr->WATCH_STYLE.num_valid);
+ for (i = 0; i < current_cpu_data.watch_reg_use_cnt; i++) {
+ __put_user(child->thread.watch.mips3264.watchlo[i],
+ &addr->WATCH_STYLE.watchlo[i]);
+ __put_user(child->thread.watch.mips3264.watchhi[i] & 0xfff,
+ &addr->WATCH_STYLE.watchhi[i]);
+ __put_user(current_cpu_data.watch_reg_masks[i],
+ &addr->WATCH_STYLE.watch_masks[i]);
+ }
+ for (; i < 8; i++) {
+ __put_user(0, &addr->WATCH_STYLE.watchlo[i]);
+ __put_user(0, &addr->WATCH_STYLE.watchhi[i]);
+ __put_user(0, &addr->WATCH_STYLE.watch_masks[i]);
+ }
+
+ return 0;
+}
+
+int ptrace_set_watch_regs(struct task_struct *child,
+ struct pt_watch_regs __user *addr)
+{
+ int i;
+ int watch_active = 0;
+ unsigned long lt[NUM_WATCH_REGS];
+ u16 ht[NUM_WATCH_REGS];
+
+ if (!cpu_has_watch || current_cpu_data.watch_reg_use_cnt == 0)
+ return -EIO;
+ if (!access_ok(VERIFY_READ, addr, sizeof(struct pt_watch_regs)))
+ return -EIO;
+ /* Check the values. */
+ for (i = 0; i < current_cpu_data.watch_reg_use_cnt; i++) {
+ __get_user(lt[i], &addr->WATCH_STYLE.watchlo[i]);
+#ifdef CONFIG_32BIT
+ if (lt[i] & __UA_LIMIT)
+ return -EINVAL;
+#else
+ if (test_tsk_thread_flag(child, TIF_32BIT_ADDR)) {
+ if (lt[i] & 0xffffffff80000000UL)
+ return -EINVAL;
+ } else {
+ if (lt[i] & __UA_LIMIT)
+ return -EINVAL;
+ }
+#endif
+ __get_user(ht[i], &addr->WATCH_STYLE.watchhi[i]);
+ if (ht[i] & ~0xff8)
+ return -EINVAL;
+ }
+ /* Install them. */
+ for (i = 0; i < current_cpu_data.watch_reg_use_cnt; i++) {
+ if (lt[i] & 7)
+ watch_active = 1;
+ child->thread.watch.mips3264.watchlo[i] = lt[i];
+ /* Set the G bit. */
+ child->thread.watch.mips3264.watchhi[i] = ht[i];
+ }
+
+ if (watch_active)
+ set_tsk_thread_flag(child, TIF_LOAD_WATCH);
+ else
+ clear_tsk_thread_flag(child, TIF_LOAD_WATCH);
+
+ return 0;
+}
+
long arch_ptrace(struct task_struct *child, long request, long addr, long data)
{
int ret;
@@ -238,7 +326,7 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
case FPC_EIR: { /* implementation / version register */
unsigned int flags;
#ifdef CONFIG_MIPS_MT_SMTC
- unsigned int irqflags;
+ unsigned long irqflags;
unsigned int mtflags;
#endif /* CONFIG_MIPS_MT_SMTC */
@@ -440,6 +528,16 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
(unsigned long __user *) data);
break;
+ case PTRACE_GET_WATCH_REGS:
+ ret = ptrace_get_watch_regs(child,
+ (struct pt_watch_regs __user *) addr);
+ break;
+
+ case PTRACE_SET_WATCH_REGS:
+ ret = ptrace_set_watch_regs(child,
+ (struct pt_watch_regs __user *) addr);
+ break;
+
default:
ret = ptrace_request(child, request, addr, data);
break;
diff --git a/arch/mips/kernel/ptrace32.c b/arch/mips/kernel/ptrace32.c
index 76818be6ba7..1ca34104e59 100644
--- a/arch/mips/kernel/ptrace32.c
+++ b/arch/mips/kernel/ptrace32.c
@@ -15,6 +15,7 @@
* binaries.
*/
#include <linux/compiler.h>
+#include <linux/compat.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/mm.h>
@@ -36,47 +37,17 @@
#include <asm/uaccess.h>
#include <asm/bootinfo.h>
-int ptrace_getregs(struct task_struct *child, __s64 __user *data);
-int ptrace_setregs(struct task_struct *child, __s64 __user *data);
-
-int ptrace_getfpregs(struct task_struct *child, __u32 __user *data);
-int ptrace_setfpregs(struct task_struct *child, __u32 __user *data);
-
/*
* Tracing a 32-bit process with a 64-bit strace and vice versa will not
* work. I don't know how to fix this.
*/
-asmlinkage int sys32_ptrace(int request, int pid, int addr, int data)
+long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
+ compat_ulong_t caddr, compat_ulong_t cdata)
{
- struct task_struct *child;
+ int addr = caddr;
+ int data = cdata;
int ret;
-#if 0
- printk("ptrace(r=%d,pid=%d,addr=%08lx,data=%08lx)\n",
- (int) request, (int) pid, (unsigned long) addr,
- (unsigned long) data);
-#endif
- lock_kernel();
- if (request == PTRACE_TRACEME) {
- ret = ptrace_traceme();
- goto out;
- }
-
- child = ptrace_get_task_struct(pid);
- if (IS_ERR(child)) {
- ret = PTR_ERR(child);
- goto out;
- }
-
- if (request == PTRACE_ATTACH) {
- ret = ptrace_attach(child);
- goto out_tsk;
- }
-
- ret = ptrace_check_attach(child, request == PTRACE_KILL);
- if (ret < 0)
- goto out_tsk;
-
switch (request) {
/* when I and D space are separate, these will need to be fixed. */
case PTRACE_PEEKTEXT: /* read word at location addr. */
@@ -214,7 +185,7 @@ asmlinkage int sys32_ptrace(int request, int pid, int addr, int data)
if (!cpu_has_dsp) {
tmp = 0;
ret = -EIO;
- goto out_tsk;
+ goto out;
}
dregs = __get_dsp_regs(child);
tmp = (unsigned long) (dregs[addr - DSP_BASE]);
@@ -224,14 +195,14 @@ asmlinkage int sys32_ptrace(int request, int pid, int addr, int data)
if (!cpu_has_dsp) {
tmp = 0;
ret = -EIO;
- goto out_tsk;
+ goto out;
}
tmp = child->thread.dsp.dspcontrol;
break;
default:
tmp = 0;
ret = -EIO;
- goto out_tsk;
+ goto out;
}
ret = put_user(tmp, (unsigned __user *) (unsigned long) data);
break;
@@ -410,14 +381,20 @@ asmlinkage int sys32_ptrace(int request, int pid, int addr, int data)
(unsigned long __user *) (unsigned long) data);
break;
+ case PTRACE_GET_WATCH_REGS:
+ ret = ptrace_get_watch_regs(child,
+ (struct pt_watch_regs __user *) (unsigned long) addr);
+ break;
+
+ case PTRACE_SET_WATCH_REGS:
+ ret = ptrace_set_watch_regs(child,
+ (struct pt_watch_regs __user *) (unsigned long) addr);
+ break;
+
default:
ret = ptrace_request(child, request, addr, data);
break;
}
-
-out_tsk:
- put_task_struct(child);
out:
- unlock_kernel();
return ret;
}
diff --git a/arch/mips/kernel/scall64-n32.S b/arch/mips/kernel/scall64-n32.S
index da7f1b6ea0f..324c5499dec 100644
--- a/arch/mips/kernel/scall64-n32.S
+++ b/arch/mips/kernel/scall64-n32.S
@@ -219,7 +219,7 @@ EXPORT(sysn32_call_table)
PTR compat_sys_getrusage
PTR compat_sys_sysinfo
PTR compat_sys_times
- PTR sys32_ptrace
+ PTR compat_sys_ptrace
PTR sys_getuid /* 6100 */
PTR sys_syslog
PTR sys_getgid
diff --git a/arch/mips/kernel/scall64-o32.S b/arch/mips/kernel/scall64-o32.S
index d7cd1aac9ad..85fedac99a5 100644
--- a/arch/mips/kernel/scall64-o32.S
+++ b/arch/mips/kernel/scall64-o32.S
@@ -231,7 +231,7 @@ sys_call_table:
PTR sys_setuid
PTR sys_getuid
PTR compat_sys_stime /* 4025 */
- PTR sys32_ptrace
+ PTR compat_sys_ptrace
PTR sys_alarm
PTR sys_ni_syscall /* was sys_fstat */
PTR sys_pause
diff --git a/arch/mips/kernel/signal32.c b/arch/mips/kernel/signal32.c
index 572c610db1b..652709b353a 100644
--- a/arch/mips/kernel/signal32.c
+++ b/arch/mips/kernel/signal32.c
@@ -482,6 +482,18 @@ int copy_siginfo_to_user32(compat_siginfo_t __user *to, siginfo_t *from)
return err;
}
+int copy_siginfo_from_user32(siginfo_t *to, compat_siginfo_t __user *from)
+{
+ memset(to, 0, sizeof *to);
+
+ if (copy_from_user(to, from, 3*sizeof(int)) ||
+ copy_from_user(to->_sifields._pad,
+ from->_sifields._pad, SI_PAD_SIZE32))
+ return -EFAULT;
+
+ return 0;
+}
+
asmlinkage void sys32_sigreturn(nabi_no_regargs struct pt_regs regs)
{
struct sigframe32 __user *frame;
diff --git a/arch/mips/kernel/smp.c b/arch/mips/kernel/smp.c
index 4410f172b8a..7b59cfb7e60 100644
--- a/arch/mips/kernel/smp.c
+++ b/arch/mips/kernel/smp.c
@@ -121,6 +121,8 @@ asmlinkage __cpuinit void start_secondary(void)
cpu = smp_processor_id();
cpu_data[cpu].udelay_val = loops_per_jiffy;
+ notify_cpu_starting(cpu);
+
mp_ops->smp_finish();
set_cpu_sibling_map(cpu);
diff --git a/arch/mips/kernel/smtc.c b/arch/mips/kernel/smtc.c
index a516286532a..897fb2b4751 100644
--- a/arch/mips/kernel/smtc.c
+++ b/arch/mips/kernel/smtc.c
@@ -1,4 +1,21 @@
-/* Copyright (C) 2004 Mips Technologies, Inc */
+/*
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *
+ * Copyright (C) 2004 Mips Technologies, Inc
+ * Copyright (C) 2008 Kevin D. Kissell
+ */
#include <linux/clockchips.h>
#include <linux/kernel.h>
@@ -21,7 +38,6 @@
#include <asm/time.h>
#include <asm/addrspace.h>
#include <asm/smtc.h>
-#include <asm/smtc_ipi.h>
#include <asm/smtc_proc.h>
/*
@@ -58,11 +74,6 @@ unsigned long irq_hwmask[NR_IRQS];
asiduse smtc_live_asid[MAX_SMTC_TLBS][MAX_SMTC_ASIDS];
-/*
- * Clock interrupt "latch" buffers, per "CPU"
- */
-
-static atomic_t ipi_timer_latch[NR_CPUS];
/*
* Number of InterProcessor Interrupt (IPI) message buffers to allocate
@@ -70,7 +81,7 @@ static atomic_t ipi_timer_latch[NR_CPUS];
#define IPIBUF_PER_CPU 4
-static struct smtc_ipi_q IPIQ[NR_CPUS];
+struct smtc_ipi_q IPIQ[NR_CPUS];
static struct smtc_ipi_q freeIPIq;
@@ -282,7 +293,7 @@ static void smtc_configure_tlb(void)
* phys_cpu_present_map and the logical/physical mappings.
*/
-int __init mipsmt_build_cpu_map(int start_cpu_slot)
+int __init smtc_build_cpu_map(int start_cpu_slot)
{
int i, ntcs;
@@ -325,7 +336,12 @@ static void smtc_tc_setup(int vpe, int tc, int cpu)
write_tc_c0_tcstatus((read_tc_c0_tcstatus()
& ~(TCSTATUS_TKSU | TCSTATUS_DA | TCSTATUS_IXMT))
| TCSTATUS_A);
- write_tc_c0_tccontext(0);
+ /*
+ * TCContext gets an offset from the base of the IPIQ array
+ * to be used in low-level code to detect the presence of
+ * an active IPI queue
+ */
+ write_tc_c0_tccontext((sizeof(struct smtc_ipi_q) * cpu) << 16);
/* Bind tc to vpe */
write_tc_c0_tcbind(vpe);
/* In general, all TCs should have the same cpu_data indications */
@@ -336,10 +352,18 @@ static void smtc_tc_setup(int vpe, int tc, int cpu)
cpu_data[cpu].options &= ~MIPS_CPU_FPU;
cpu_data[cpu].vpe_id = vpe;
cpu_data[cpu].tc_id = tc;
+ /* Multi-core SMTC hasn't been tested, but be prepared */
+ cpu_data[cpu].core = (read_vpe_c0_ebase() >> 1) & 0xff;
}
+/*
+ * Tweak to get Count registes in as close a sync as possible.
+ * Value seems good for 34K-class cores.
+ */
+
+#define CP0_SKEW 8
-void mipsmt_prepare_cpus(void)
+void smtc_prepare_cpus(int cpus)
{
int i, vpe, tc, ntc, nvpe, tcpervpe[NR_CPUS], slop, cpu;
unsigned long flags;
@@ -363,13 +387,13 @@ void mipsmt_prepare_cpus(void)
IPIQ[i].head = IPIQ[i].tail = NULL;
spin_lock_init(&IPIQ[i].lock);
IPIQ[i].depth = 0;
- atomic_set(&ipi_timer_latch[i], 0);
}
/* cpu_data index starts at zero */
cpu = 0;
cpu_data[cpu].vpe_id = 0;
cpu_data[cpu].tc_id = 0;
+ cpu_data[cpu].core = (read_c0_ebase() >> 1) & 0xff;
cpu++;
/* Report on boot-time options */
@@ -484,7 +508,8 @@ void mipsmt_prepare_cpus(void)
write_vpe_c0_compare(0);
/* Propagate Config7 */
write_vpe_c0_config7(read_c0_config7());
- write_vpe_c0_count(read_c0_count());
+ write_vpe_c0_count(read_c0_count() + CP0_SKEW);
+ ehb();
}
/* enable multi-threading within VPE */
write_vpe_c0_vpecontrol(read_vpe_c0_vpecontrol() | VPECONTROL_TE);
@@ -556,7 +581,7 @@ void mipsmt_prepare_cpus(void)
void __cpuinit smtc_boot_secondary(int cpu, struct task_struct *idle)
{
extern u32 kernelsp[NR_CPUS];
- long flags;
+ unsigned long flags;
int mtflags;
LOCK_MT_PRA();
@@ -585,24 +610,22 @@ void __cpuinit smtc_boot_secondary(int cpu, struct task_struct *idle)
void smtc_init_secondary(void)
{
- /*
- * Start timer on secondary VPEs if necessary.
- * plat_timer_setup has already have been invoked by init/main
- * on "boot" TC. Like per_cpu_trap_init() hack, this assumes that
- * SMTC init code assigns TCs consdecutively and in ascending order
- * to across available VPEs.
- */
- if (((read_c0_tcbind() & TCBIND_CURTC) != 0) &&
- ((read_c0_tcbind() & TCBIND_CURVPE)
- != cpu_data[smp_processor_id() - 1].vpe_id)){
- write_c0_compare(read_c0_count() + mips_hpt_frequency/HZ);
- }
-
local_irq_enable();
}
void smtc_smp_finish(void)
{
+ int cpu = smp_processor_id();
+
+ /*
+ * Lowest-numbered CPU per VPE starts a clock tick.
+ * Like per_cpu_trap_init() hack, this assumes that
+ * SMTC init code assigns TCs consdecutively and
+ * in ascending order across available VPEs.
+ */
+ if (cpu > 0 && (cpu_data[cpu].vpe_id != cpu_data[cpu - 1].vpe_id))
+ write_c0_compare(read_c0_count() + mips_hpt_frequency/HZ);
+
printk("TC %d going on-line as CPU %d\n",
cpu_data[smp_processor_id()].tc_id, smp_processor_id());
}
@@ -753,8 +776,10 @@ void smtc_send_ipi(int cpu, int type, unsigned int action)
{
int tcstatus;
struct smtc_ipi *pipi;
- long flags;
+ unsigned long flags;
int mtflags;
+ unsigned long tcrestart;
+ extern void r4k_wait_irqoff(void), __pastwait(void);
if (cpu == smp_processor_id()) {
printk("Cannot Send IPI to self!\n");
@@ -771,8 +796,6 @@ void smtc_send_ipi(int cpu, int type, unsigned int action)
pipi->arg = (void *)action;
pipi->dest = cpu;
if (cpu_data[cpu].vpe_id != cpu_data[smp_processor_id()].vpe_id) {
- if (type == SMTC_CLOCK_TICK)
- atomic_inc(&ipi_timer_latch[cpu]);
/* If not on same VPE, enqueue and send cross-VPE interrupt */
smtc_ipi_nq(&IPIQ[cpu], pipi);
LOCK_CORE_PRA();
@@ -800,22 +823,29 @@ void smtc_send_ipi(int cpu, int type, unsigned int action)
if ((tcstatus & TCSTATUS_IXMT) != 0) {
/*
- * Spin-waiting here can deadlock,
- * so we queue the message for the target TC.
+ * If we're in the the irq-off version of the wait
+ * loop, we need to force exit from the wait and
+ * do a direct post of the IPI.
+ */
+ if (cpu_wait == r4k_wait_irqoff) {
+ tcrestart = read_tc_c0_tcrestart();
+ if (tcrestart >= (unsigned long)r4k_wait_irqoff
+ && tcrestart < (unsigned long)__pastwait) {
+ write_tc_c0_tcrestart(__pastwait);
+ tcstatus &= ~TCSTATUS_IXMT;
+ write_tc_c0_tcstatus(tcstatus);
+ goto postdirect;
+ }
+ }
+ /*
+ * Otherwise we queue the message for the target TC
+ * to pick up when he does a local_irq_restore()
*/
write_tc_c0_tchalt(0);
UNLOCK_CORE_PRA();
- /* Try to reduce redundant timer interrupt messages */
- if (type == SMTC_CLOCK_TICK) {
- if (atomic_postincrement(&ipi_timer_latch[cpu])!=0){
- smtc_ipi_nq(&freeIPIq, pipi);
- return;
- }
- }
smtc_ipi_nq(&IPIQ[cpu], pipi);
} else {
- if (type == SMTC_CLOCK_TICK)
- atomic_inc(&ipi_timer_latch[cpu]);
+postdirect:
post_direct_ipi(cpu, pipi);
write_tc_c0_tchalt(0);
UNLOCK_CORE_PRA();
@@ -883,7 +913,7 @@ static void ipi_call_interrupt(void)
smp_call_function_interrupt();
}
-DECLARE_PER_CPU(struct clock_event_device, smtc_dummy_clockevent_device);
+DECLARE_PER_CPU(struct clock_event_device, mips_clockevent_device);
void ipi_decode(struct smtc_ipi *pipi)
{
@@ -891,20 +921,13 @@ void ipi_decode(struct smtc_ipi *pipi)
struct clock_event_device *cd;
void *arg_copy = pipi->arg;
int type_copy = pipi->type;
- int ticks;
-
smtc_ipi_nq(&freeIPIq, pipi);
switch (type_copy) {
case SMTC_CLOCK_TICK:
irq_enter();
kstat_this_cpu.irqs[MIPS_CPU_IRQ_BASE + 1]++;
- cd = &per_cpu(smtc_dummy_clockevent_device, cpu);
- ticks = atomic_read(&ipi_timer_latch[cpu]);
- atomic_sub(ticks, &ipi_timer_latch[cpu]);
- while (ticks) {
- cd->event_handler(cd);
- ticks--;
- }
+ cd = &per_cpu(mips_clockevent_device, cpu);
+ cd->event_handler(cd);
irq_exit();
break;
@@ -937,24 +960,48 @@ void ipi_decode(struct smtc_ipi *pipi)
}
}
+/*
+ * Similar to smtc_ipi_replay(), but invoked from context restore,
+ * so it reuses the current exception frame rather than set up a
+ * new one with self_ipi.
+ */
+
void deferred_smtc_ipi(void)
{
- struct smtc_ipi *pipi;
- unsigned long flags;
-/* DEBUG */
- int q = smp_processor_id();
+ int cpu = smp_processor_id();
/*
* Test is not atomic, but much faster than a dequeue,
* and the vast majority of invocations will have a null queue.
+ * If irq_disabled when this was called, then any IPIs queued
+ * after we test last will be taken on the next irq_enable/restore.
+ * If interrupts were enabled, then any IPIs added after the
+ * last test will be taken directly.
*/
- if (IPIQ[q].head != NULL) {
- while((pipi = smtc_ipi_dq(&IPIQ[q])) != NULL) {
- /* ipi_decode() should be called with interrupts off */
- local_irq_save(flags);
+
+ while (IPIQ[cpu].head != NULL) {
+ struct smtc_ipi_q *q = &IPIQ[cpu];
+ struct smtc_ipi *pipi;
+ unsigned long flags;
+
+ /*
+ * It may be possible we'll come in with interrupts
+ * already enabled.
+ */
+ local_irq_save(flags);
+
+ spin_lock(&q->lock);
+ pipi = __smtc_ipi_dq(q);
+ spin_unlock(&q->lock);
+ if (pipi != NULL)
ipi_decode(pipi);
- local_irq_restore(flags);
- }
+ /*
+ * The use of the __raw_local restore isn't
+ * as obviously necessary here as in smtc_ipi_replay(),
+ * but it's more efficient, given that we're already
+ * running down the IPI queue.
+ */
+ __raw_local_irq_restore(flags);
}
}
@@ -975,7 +1022,7 @@ static irqreturn_t ipi_interrupt(int irq, void *dev_idm)
struct smtc_ipi *pipi;
unsigned long tcstatus;
int sent;
- long flags;
+ unsigned long flags;
unsigned int mtflags;
unsigned int vpflags;
@@ -1066,55 +1113,53 @@ static void setup_cross_vpe_interrupts(unsigned int nvpe)
/*
* SMTC-specific hacks invoked from elsewhere in the kernel.
- *
- * smtc_ipi_replay is called from raw_local_irq_restore which is only ever
- * called with interrupts disabled. We do rely on interrupts being disabled
- * here because using spin_lock_irqsave()/spin_unlock_irqrestore() would
- * result in a recursive call to raw_local_irq_restore().
*/
-static void __smtc_ipi_replay(void)
+ /*
+ * smtc_ipi_replay is called from raw_local_irq_restore
+ */
+
+void smtc_ipi_replay(void)
{
unsigned int cpu = smp_processor_id();
/*
* To the extent that we've ever turned interrupts off,
* we may have accumulated deferred IPIs. This is subtle.
- * If we use the smtc_ipi_qdepth() macro, we'll get an
- * exact number - but we'll also disable interrupts
- * and create a window of failure where a new IPI gets
- * queued after we test the depth but before we re-enable
- * interrupts. So long as IXMT never gets set, however,
* we should be OK: If we pick up something and dispatch
* it here, that's great. If we see nothing, but concurrent
* with this operation, another TC sends us an IPI, IXMT
* is clear, and we'll handle it as a real pseudo-interrupt
- * and not a pseudo-pseudo interrupt.
+ * and not a pseudo-pseudo interrupt. The important thing
+ * is to do the last check for queued message *after* the
+ * re-enabling of interrupts.
*/
- if (IPIQ[cpu].depth > 0) {
- while (1) {
- struct smtc_ipi_q *q = &IPIQ[cpu];
- struct smtc_ipi *pipi;
- extern void self_ipi(struct smtc_ipi *);
-
- spin_lock(&q->lock);
- pipi = __smtc_ipi_dq(q);
- spin_unlock(&q->lock);
- if (!pipi)
- break;
+ while (IPIQ[cpu].head != NULL) {
+ struct smtc_ipi_q *q = &IPIQ[cpu];
+ struct smtc_ipi *pipi;
+ unsigned long flags;
+
+ /*
+ * It's just possible we'll come in with interrupts
+ * already enabled.
+ */
+ local_irq_save(flags);
+
+ spin_lock(&q->lock);
+ pipi = __smtc_ipi_dq(q);
+ spin_unlock(&q->lock);
+ /*
+ ** But use a raw restore here to avoid recursion.
+ */
+ __raw_local_irq_restore(flags);
+ if (pipi) {
self_ipi(pipi);
smtc_cpu_stats[cpu].selfipis++;
}
}
}
-void smtc_ipi_replay(void)
-{
- raw_local_irq_disable();
- __smtc_ipi_replay();
-}
-
EXPORT_SYMBOL(smtc_ipi_replay);
void smtc_idle_loop_hook(void)
@@ -1193,40 +1238,13 @@ void smtc_idle_loop_hook(void)
}
}
- /*
- * Now that we limit outstanding timer IPIs, check for hung TC
- */
- for (tc = 0; tc < NR_CPUS; tc++) {
- /* Don't check ourself - we'll dequeue IPIs just below */
- if ((tc != smp_processor_id()) &&
- atomic_read(&ipi_timer_latch[tc]) > timerq_limit) {
- if (clock_hang_reported[tc] == 0) {
- pdb_msg += sprintf(pdb_msg,
- "TC %d looks hung with timer latch at %d\n",
- tc, atomic_read(&ipi_timer_latch[tc]));
- clock_hang_reported[tc]++;
- }
- }
- }
emt(mtflags);
local_irq_restore(flags);
if (pdb_msg != &id_ho_db_msg[0])
printk("CPU%d: %s", smp_processor_id(), id_ho_db_msg);
#endif /* CONFIG_SMTC_IDLE_HOOK_DEBUG */
- /*
- * Replay any accumulated deferred IPIs. If "Instant Replay"
- * is in use, there should never be any.
- */
-#ifndef CONFIG_MIPS_MT_SMTC_INSTANT_REPLAY
- {
- unsigned long flags;
-
- local_irq_save(flags);
- __smtc_ipi_replay();
- local_irq_restore(flags);
- }
-#endif /* CONFIG_MIPS_MT_SMTC_INSTANT_REPLAY */
+ smtc_ipi_replay();
}
void smtc_soft_dump(void)
@@ -1242,10 +1260,6 @@ void smtc_soft_dump(void)
printk("%d: %ld\n", i, smtc_cpu_stats[i].selfipis);
}
smtc_ipi_qdump();
- printk("Timer IPI Backlogs:\n");
- for (i=0; i < NR_CPUS; i++) {
- printk("%d: %d\n", i, atomic_read(&ipi_timer_latch[i]));
- }
printk("%d Recoveries of \"stolen\" FPU\n",
atomic_read(&smtc_fpu_recoveries));
}
diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c
index 6bee29097a5..80b9e070c20 100644
--- a/arch/mips/kernel/traps.c
+++ b/arch/mips/kernel/traps.c
@@ -42,10 +42,14 @@
#include <asm/tlbdebug.h>
#include <asm/traps.h>
#include <asm/uaccess.h>
+#include <asm/watch.h>
#include <asm/mmu_context.h>
#include <asm/types.h>
#include <asm/stacktrace.h>
+extern void check_wait(void);
+extern asmlinkage void r4k_wait(void);
+extern asmlinkage void rollback_handle_int(void);
extern asmlinkage void handle_int(void);
extern asmlinkage void handle_tlbm(void);
extern asmlinkage void handle_tlbl(void);
@@ -822,8 +826,10 @@ static void mt_ase_fp_affinity(void)
if (cpus_intersects(current->cpus_allowed, mt_fpu_cpumask)) {
cpumask_t tmask;
- cpus_and(tmask, current->thread.user_cpus_allowed,
- mt_fpu_cpumask);
+ current->thread.user_cpus_allowed
+ = current->cpus_allowed;
+ cpus_and(tmask, current->cpus_allowed,
+ mt_fpu_cpumask);
set_cpus_allowed(current, tmask);
set_thread_flag(TIF_FPUBOUND);
}
@@ -907,13 +913,26 @@ asmlinkage void do_mdmx(struct pt_regs *regs)
asmlinkage void do_watch(struct pt_regs *regs)
{
+ u32 cause;
+
/*
- * We use the watch exception where available to detect stack
- * overflows.
+ * Clear WP (bit 22) bit of cause register so we don't loop
+ * forever.
*/
- dump_tlb_all();
- show_regs(regs);
- panic("Caught WATCH exception - probably caused by stack overflow.");
+ cause = read_c0_cause();
+ cause &= ~(1 << 22);
+ write_c0_cause(cause);
+
+ /*
+ * If the current thread has the watch registers loaded, save
+ * their values and send SIGTRAP. Otherwise another thread
+ * left the registers set, clear them and continue.
+ */
+ if (test_tsk_thread_flag(current, TIF_LOAD_WATCH)) {
+ mips_read_watch_registers();
+ force_sig(SIGTRAP, current);
+ } else
+ mips_clear_watch_registers();
}
asmlinkage void do_mcheck(struct pt_regs *regs)
@@ -1251,6 +1270,9 @@ static void *set_vi_srs_handler(int n, vi_handler_t addr, int srs)
extern char except_vec_vi, except_vec_vi_lui;
extern char except_vec_vi_ori, except_vec_vi_end;
+ extern char rollback_except_vec_vi;
+ char *vec_start = (cpu_wait == r4k_wait) ?
+ &rollback_except_vec_vi : &except_vec_vi;
#ifdef CONFIG_MIPS_MT_SMTC
/*
* We need to provide the SMTC vectored interrupt handler
@@ -1258,11 +1280,11 @@ static void *set_vi_srs_handler(int n, vi_handler_t addr, int srs)
* Status.IM bit to be masked before going there.
*/
extern char except_vec_vi_mori;
- const int mori_offset = &except_vec_vi_mori - &except_vec_vi;
+ const int mori_offset = &except_vec_vi_mori - vec_start;
#endif /* CONFIG_MIPS_MT_SMTC */
- const int handler_len = &except_vec_vi_end - &except_vec_vi;
- const int lui_offset = &except_vec_vi_lui - &except_vec_vi;
- const int ori_offset = &except_vec_vi_ori - &except_vec_vi;
+ const int handler_len = &except_vec_vi_end - vec_start;
+ const int lui_offset = &except_vec_vi_lui - vec_start;
+ const int ori_offset = &except_vec_vi_ori - vec_start;
if (handler_len > VECTORSPACING) {
/*
@@ -1272,7 +1294,7 @@ static void *set_vi_srs_handler(int n, vi_handler_t addr, int srs)
panic("VECTORSPACING too small");
}
- memcpy(b, &except_vec_vi, handler_len);
+ memcpy(b, vec_start, handler_len);
#ifdef CONFIG_MIPS_MT_SMTC
BUG_ON(n > 7); /* Vector index %d exceeds SMTC maximum. */
@@ -1554,6 +1576,10 @@ void __init trap_init(void)
extern char except_vec3_generic, except_vec3_r4000;
extern char except_vec4;
unsigned long i;
+ int rollback;
+
+ check_wait();
+ rollback = (cpu_wait == r4k_wait);
#if defined(CONFIG_KGDB)
if (kgdb_early_setup)
@@ -1618,7 +1644,7 @@ void __init trap_init(void)
if (board_be_init)
board_be_init();
- set_except_vector(0, handle_int);
+ set_except_vector(0, rollback ? rollback_handle_int : handle_int);
set_except_vector(1, handle_tlbm);
set_except_vector(2, handle_tlbl);
set_except_vector(3, handle_tlbs);
diff --git a/arch/mips/kernel/vmlinux.lds.S b/arch/mips/kernel/vmlinux.lds.S
index b5470ceb418..afb119f3568 100644
--- a/arch/mips/kernel/vmlinux.lds.S
+++ b/arch/mips/kernel/vmlinux.lds.S
@@ -36,6 +36,7 @@ SECTIONS
SCHED_TEXT
LOCK_TEXT
KPROBES_TEXT
+ *(.text.*)
*(.fixup)
*(.gnu.warning)
} :text = 0
diff --git a/arch/mips/kernel/watch.c b/arch/mips/kernel/watch.c
new file mode 100644
index 00000000000..c1540696803
--- /dev/null
+++ b/arch/mips/kernel/watch.c
@@ -0,0 +1,188 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2008 David Daney
+ */
+
+#include <linux/sched.h>
+
+#include <asm/processor.h>
+#include <asm/watch.h>
+
+/*
+ * Install the watch registers for the current thread. A maximum of
+ * four registers are installed although the machine may have more.
+ */
+void mips_install_watch_registers(void)
+{
+ struct mips3264_watch_reg_state *watches =
+ &current->thread.watch.mips3264;
+ switch (current_cpu_data.watch_reg_use_cnt) {
+ default:
+ BUG();
+ case 4:
+ write_c0_watchlo3(watches->watchlo[3]);
+ /* Write 1 to the I, R, and W bits to clear them, and
+ 1 to G so all ASIDs are trapped. */
+ write_c0_watchhi3(0x40000007 | watches->watchhi[3]);
+ case 3:
+ write_c0_watchlo2(watches->watchlo[2]);
+ write_c0_watchhi2(0x40000007 | watches->watchhi[2]);
+ case 2:
+ write_c0_watchlo1(watches->watchlo[1]);
+ write_c0_watchhi1(0x40000007 | watches->watchhi[1]);
+ case 1:
+ write_c0_watchlo0(watches->watchlo[0]);
+ write_c0_watchhi0(0x40000007 | watches->watchhi[0]);
+ }
+}
+
+/*
+ * Read back the watchhi registers so the user space debugger has
+ * access to the I, R, and W bits. A maximum of four registers are
+ * read although the machine may have more.
+ */
+void mips_read_watch_registers(void)
+{
+ struct mips3264_watch_reg_state *watches =
+ &current->thread.watch.mips3264;
+ switch (current_cpu_data.watch_reg_use_cnt) {
+ default:
+ BUG();
+ case 4:
+ watches->watchhi[3] = (read_c0_watchhi3() & 0x0fff);
+ case 3:
+ watches->watchhi[2] = (read_c0_watchhi2() & 0x0fff);
+ case 2:
+ watches->watchhi[1] = (read_c0_watchhi1() & 0x0fff);
+ case 1:
+ watches->watchhi[0] = (read_c0_watchhi0() & 0x0fff);
+ }
+ if (current_cpu_data.watch_reg_use_cnt == 1 &&
+ (watches->watchhi[0] & 7) == 0) {
+ /* Pathological case of release 1 architecture that
+ * doesn't set the condition bits. We assume that
+ * since we got here, the watch condition was met and
+ * signal that the conditions requested in watchlo
+ * were met. */
+ watches->watchhi[0] |= (watches->watchlo[0] & 7);
+ }
+ }
+
+/*
+ * Disable all watch registers. Although only four registers are
+ * installed, all are cleared to eliminate the possibility of endless
+ * looping in the watch handler.
+ */
+void mips_clear_watch_registers(void)
+{
+ switch (current_cpu_data.watch_reg_count) {
+ default:
+ BUG();
+ case 8:
+ write_c0_watchlo7(0);
+ case 7:
+ write_c0_watchlo6(0);
+ case 6:
+ write_c0_watchlo5(0);
+ case 5:
+ write_c0_watchlo4(0);
+ case 4:
+ write_c0_watchlo3(0);
+ case 3:
+ write_c0_watchlo2(0);
+ case 2:
+ write_c0_watchlo1(0);
+ case 1:
+ write_c0_watchlo0(0);
+ }
+}
+
+__cpuinit void mips_probe_watch_registers(struct cpuinfo_mips *c)
+{
+ unsigned int t;
+
+ if ((c->options & MIPS_CPU_WATCH) == 0)
+ return;
+ /*
+ * Check which of the I,R and W bits are supported, then
+ * disable the register.
+ */
+ write_c0_watchlo0(7);
+ t = read_c0_watchlo0();
+ write_c0_watchlo0(0);
+ c->watch_reg_masks[0] = t & 7;
+
+ /* Write the mask bits and read them back to determine which
+ * can be used. */
+ c->watch_reg_count = 1;
+ c->watch_reg_use_cnt = 1;
+ t = read_c0_watchhi0();
+ write_c0_watchhi0(t | 0xff8);
+ t = read_c0_watchhi0();
+ c->watch_reg_masks[0] |= (t & 0xff8);
+ if ((t & 0x80000000) == 0)
+ return;
+
+ write_c0_watchlo1(7);
+ t = read_c0_watchlo1();
+ write_c0_watchlo1(0);
+ c->watch_reg_masks[1] = t & 7;
+
+ c->watch_reg_count = 2;
+ c->watch_reg_use_cnt = 2;
+ t = read_c0_watchhi1();
+ write_c0_watchhi1(t | 0xff8);
+ t = read_c0_watchhi1();
+ c->watch_reg_masks[1] |= (t & 0xff8);
+ if ((t & 0x80000000) == 0)
+ return;
+
+ write_c0_watchlo2(7);
+ t = read_c0_watchlo2();
+ write_c0_watchlo2(0);
+ c->watch_reg_masks[2] = t & 7;
+
+ c->watch_reg_count = 3;
+ c->watch_reg_use_cnt = 3;
+ t = read_c0_watchhi2();
+ write_c0_watchhi2(t | 0xff8);
+ t = read_c0_watchhi2();
+ c->watch_reg_masks[2] |= (t & 0xff8);
+ if ((t & 0x80000000) == 0)
+ return;
+
+ write_c0_watchlo3(7);
+ t = read_c0_watchlo3();
+ write_c0_watchlo3(0);
+ c->watch_reg_masks[3] = t & 7;
+
+ c->watch_reg_count = 4;
+ c->watch_reg_use_cnt = 4;
+ t = read_c0_watchhi3();
+ write_c0_watchhi3(t | 0xff8);
+ t = read_c0_watchhi3();
+ c->watch_reg_masks[3] |= (t & 0xff8);
+ if ((t & 0x80000000) == 0)
+ return;
+
+ /* We use at most 4, but probe and report up to 8. */
+ c->watch_reg_count = 5;
+ t = read_c0_watchhi4();
+ if ((t & 0x80000000) == 0)
+ return;
+
+ c->watch_reg_count = 6;
+ t = read_c0_watchhi5();
+ if ((t & 0x80000000) == 0)
+ return;
+
+ c->watch_reg_count = 7;
+ t = read_c0_watchhi6();
+ if ((t & 0x80000000) == 0)
+ return;
+
+ c->watch_reg_count = 8;
+}