6 files changed, 139 insertions, 21 deletions

diff --git a/include/asm-mips/cevt-r4k.h b/include/asm-mips/cevt-r4k.h
new file mode 100644
index 000000000000..fa4328f9124f
--- /dev/null
+++ b/include/asm-mips/cevt-r4k.h
@@ -0,0 +1,46 @@
+/*
+ * 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 Kevin D. Kissell
+ */
+
+/*
+ * Definitions used for common event timer implementation
+ * for MIPS 4K-type processors and their MIPS MT variants.
+ * Avoids unsightly extern declarations in C files.
+ */
+#ifndef __ASM_CEVT_R4K_H
+#define __ASM_CEVT_R4K_H
+
+DECLARE_PER_CPU(struct clock_event_device, mips_clockevent_device);
+
+void mips_event_handler(struct clock_event_device *dev);
+int c0_compare_int_usable(void);
+void mips_set_clock_mode(enum clock_event_mode, struct clock_event_device *);
+irqreturn_t c0_compare_interrupt(int, void *);
+
+extern struct irqaction c0_compare_irqaction;
+extern int cp0_timer_irq_installed;
+
+/*
+ * 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;
+}
+
+#endif /* __ASM_CEVT_R4K_H */
diff --git a/include/asm-mips/irqflags.h b/include/asm-mips/irqflags.h
index 881e8866501d..701ec0ba8fa9 100644
--- a/include/asm-mips/irqflags.h
+++ b/include/asm-mips/irqflags.h
@@ -38,8 +38,17 @@ __asm__(
         "       .set    pop                                             \n"
         "       .endm");
 
+extern void smtc_ipi_replay(void);
+
 static inline void raw_local_irq_enable(void)
 {
+#ifdef CONFIG_MIPS_MT_SMTC
+        /*
+         * SMTC kernel needs to do a software replay of queued
+         * IPIs, at the cost of call overhead on each local_irq_enable()
+         */
+        smtc_ipi_replay();
+#endif
         __asm__ __volatile__(
                 "raw_local_irq_enable"
                 : /* no outputs */
@@ -47,6 +56,7 @@ static inline void raw_local_irq_enable(void)
                 : "memory");
 }
 
+
 /*
  * For cli() we have to insert nops to make sure that the new value
  * has actually arrived in the status register before the end of this
@@ -185,15 +195,14 @@ __asm__(
         "       .set    pop                                             \n"
         "       .endm                                                   \n");
 
-extern void smtc_ipi_replay(void);
 
 static inline void raw_local_irq_restore(unsigned long flags)
 {
         unsigned long __tmp1;
 
-#ifdef CONFIG_MIPS_MT_SMTC_INSTANT_REPLAY
+#ifdef CONFIG_MIPS_MT_SMTC
         /*
-         * CONFIG_MIPS_MT_SMTC_INSTANT_REPLAY does prompt replay of deferred
+         * SMTC kernel needs to do a software replay of queued
          * IPIs, at the cost of branch and call overhead on each
          * local_irq_restore()
          */
@@ -208,6 +217,17 @@ static inline void raw_local_irq_restore(unsigned long flags)
                 : "memory");
 }
 
+static inline void __raw_local_irq_restore(unsigned long flags)
+{
+        unsigned long __tmp1;
+
+        __asm__ __volatile__(
+                "raw_local_irq_restore\t%0"
+                : "=r" (__tmp1)
+                : "0" (flags)
+                : "memory");
+}
+
 static inline int raw_irqs_disabled_flags(unsigned long flags)
 {
 #ifdef CONFIG_MIPS_MT_SMTC
diff --git a/include/asm-mips/mipsregs.h b/include/asm-mips/mipsregs.h
index a46f8e258e6b..979866000da4 100644
--- a/include/asm-mips/mipsregs.h
+++ b/include/asm-mips/mipsregs.h
@@ -1462,7 +1462,7 @@ set_c0_##name(unsigned int set)					\
 {                                                               \
         unsigned int res;                                       \
         unsigned int omt;                                       \
-        unsigned int flags;                                     \
+        unsigned long flags;                                    \
                                                                 \
         local_irq_save(flags);                                  \
         omt = __dmt();                                          \
@@ -1480,7 +1480,7 @@ clear_c0_##name(unsigned int clear)				\
 {                                                               \
         unsigned int res;                                       \
         unsigned int omt;                                       \
-        unsigned int flags;                                     \
+        unsigned long flags;                                    \
                                                                 \
         local_irq_save(flags);                                  \
         omt = __dmt();                                          \
@@ -1498,7 +1498,7 @@ change_c0_##name(unsigned int change, unsigned int new)		\
 {                                                               \
         unsigned int res;                                       \
         unsigned int omt;                                       \
-        unsigned int flags;                                     \
+        unsigned long flags;                                    \
                                                                 \
         local_irq_save(flags);                                  \
                                                                 \
diff --git a/include/asm-mips/pgtable-32.h b/include/asm-mips/pgtable-32.h
index 4396e9ffd418..55813d6150c7 100644
--- a/include/asm-mips/pgtable-32.h
+++ b/include/asm-mips/pgtable-32.h
@@ -57,7 +57,7 @@ extern int add_temporary_entry(unsigned long entrylo0, unsigned long entrylo1,
 #define PMD_ORDER       1
 #define PTE_ORDER       0
 
-#define PTRS_PER_PGD    ((PAGE_SIZE << PGD_ORDER) / sizeof(pgd_t))
+#define PTRS_PER_PGD    (USER_PTRS_PER_PGD * 2)
 #define PTRS_PER_PTE    ((PAGE_SIZE << PTE_ORDER) / sizeof(pte_t))
 
 #define USER_PTRS_PER_PGD       (0x80000000UL/PGDIR_SIZE)
diff --git a/include/asm-mips/smtc.h b/include/asm-mips/smtc.h
index 3639b28f80db..ea60bf08dcb0 100644
--- a/include/asm-mips/smtc.h
+++ b/include/asm-mips/smtc.h
@@ -6,6 +6,7 @@
  */
 
 #include <asm/mips_mt.h>
+#include <asm/smtc_ipi.h>
 
 /*
  * System-wide SMTC status information
@@ -38,14 +39,15 @@ struct mm_struct;
 struct task_struct;
 
 void smtc_get_new_mmu_context(struct mm_struct *mm, unsigned long cpu);
-
+void self_ipi(struct smtc_ipi *);
 void smtc_flush_tlb_asid(unsigned long asid);
-extern int mipsmt_build_cpu_map(int startslot);
-extern void mipsmt_prepare_cpus(void);
+extern int smtc_build_cpu_map(int startslot);
+extern void smtc_prepare_cpus(int cpus);
 extern void smtc_smp_finish(void);
 extern void smtc_boot_secondary(int cpu, struct task_struct *t);
 extern void smtc_cpus_done(void);
 
+
 /*
  * Sharing the TLB between multiple VPEs means that the
  * "random" index selection function is not allowed to
diff --git a/include/asm-mips/stackframe.h b/include/asm-mips/stackframe.h
index 051e1af0bb95..4c37c4e5f72e 100644
--- a/include/asm-mips/stackframe.h
+++ b/include/asm-mips/stackframe.h
@@ -297,14 +297,31 @@
 #ifdef CONFIG_MIPS_MT_SMTC
                 .set    mips32r2
                 /*
-                 * This may not really be necessary if ints are already
-                 * inhibited here.
+                 * We need to make sure the read-modify-write
+                 * of Status below isn't perturbed by an interrupt
+                 * or cross-TC access, so we need to do at least a DMT,
+                 * protected by an interrupt-inhibit. But setting IXMT
+                 * also creates a few-cycle window where an IPI could
+                 * be queued and not be detected before potentially
+                 * returning to a WAIT or user-mode loop. It must be
+                 * replayed.
+                 *
+                 * We're in the middle of a context switch, and
+                 * we can't dispatch it directly without trashing
+                 * some registers, so we'll try to detect this unlikely
+                 * case and program a software interrupt in the VPE,
+                 * as would be done for a cross-VPE IPI.  To accomodate
+                 * the handling of that case, we're doing a DVPE instead
+                 * of just a DMT here to protect against other threads.
+                 * This is a lot of cruft to cover a tiny window.
+                 * If you can find a better design, implement it!
+                 *
                  */
                 mfc0    v0, CP0_TCSTATUS
                 ori     v0, TCSTATUS_IXMT
                 mtc0    v0, CP0_TCSTATUS
                 _ehb
-                DMT     5                               # dmt a1
+                DVPE    5                               # dvpe a1
                 jal     mips_ihb
 #endif /* CONFIG_MIPS_MT_SMTC */
                 mfc0    a0, CP0_STATUS
@@ -325,17 +342,50 @@
  */
                 LONG_L  v1, PT_TCSTATUS(sp)
                 _ehb
-                mfc0    v0, CP0_TCSTATUS
+                mfc0    a0, CP0_TCSTATUS
                 andi    v1, TCSTATUS_IXMT
-                /* We know that TCStatua.IXMT should be set from above */
-                xori    v0, v0, TCSTATUS_IXMT
-                or      v0, v0, v1
-                mtc0    v0, CP0_TCSTATUS
-                _ehb
-                andi    a1, a1, VPECONTROL_TE
+                bnez    v1, 0f
+
+/*
+ * We'd like to detect any IPIs queued in the tiny window
+ * above and request an software interrupt to service them
+ * when we ERET.
+ *
+ * Computing the offset into the IPIQ array of the executing
+ * TC's IPI queue in-line would be tedious.  We use part of
+ * the TCContext register to hold 16 bits of offset that we
+ * can add in-line to find the queue head.
+ */
+                mfc0    v0, CP0_TCCONTEXT
+                la      a2, IPIQ
+                srl     v0, v0, 16
+                addu    a2, a2, v0
+                LONG_L  v0, 0(a2)
+                beqz    v0, 0f
+/*
+ * If we have a queue, provoke dispatch within the VPE by setting C_SW1
+ */
+                mfc0    v0, CP0_CAUSE
+                ori     v0, v0, C_SW1
+                mtc0    v0, CP0_CAUSE
+0:
+                /*
+                 * This test should really never branch but
+                 * let's be prudent here.  Having atomized
+                 * the shared register modifications, we can
+                 * now EVPE, and must do so before interrupts
+                 * are potentially re-enabled.
+                 */
+                andi    a1, a1, MVPCONTROL_EVP
                 beqz    a1, 1f
-                emt
+                evpe
 1:
+                /* We know that TCStatua.IXMT should be set from above */
+                xori    a0, a0, TCSTATUS_IXMT
+                or      a0, a0, v1
+                mtc0    a0, CP0_TCSTATUS
+                _ehb
+
                 .set    mips0
 #endif /* CONFIG_MIPS_MT_SMTC */
                 LONG_L  v1, PT_EPC(sp)