powerpc: Merge enough to start building in arch/powerpc.

This creates the directory structure under arch/powerpc and a bunch
of Kconfig files.  It does a first-cut merge of arch/powerpc/mm,
arch/powerpc/lib and arch/powerpc/platforms/powermac.  This is enough
to build a 32-bit powermac kernel with ARCH=powerpc.

For now we are getting some unmerged files from arch/ppc/kernel and
arch/ppc/syslib, or arch/ppc64/kernel.  This makes some minor changes
to files in those directories and files outside arch/powerpc.

The boot directory is still not merged.  That's going to be interesting.

Signed-off-by: Paul Mackerras <paulus@samba.org>

2 files changed, 905 insertions, 0 deletions

diff --git a/arch/powerpc/sysdev/Makefile b/arch/powerpc/sysdev/Makefile
new file mode 100644
index 000000000000..26bdcd9a2a43
--- /dev/null
+++ b/arch/powerpc/sysdev/Makefile
@@ -0,0 +1 @@
+obj-$(CONFIG_MPIC)      += mpic.o
diff --git a/arch/powerpc/sysdev/mpic.c b/arch/powerpc/sysdev/mpic.c
new file mode 100644
index 000000000000..c660e7d7c643
--- /dev/null
+++ b/arch/powerpc/sysdev/mpic.c
@@ -0,0 +1,904 @@
+/*
+ *  arch/powerpc/kernel/mpic.c
+ *
+ *  Driver for interrupt controllers following the OpenPIC standard, the
+ *  common implementation beeing IBM's MPIC. This driver also can deal
+ *  with various broken implementations of this HW.
+ *
+ *  Copyright (C) 2004 Benjamin Herrenschmidt, IBM Corp.
+ *
+ *  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.
+ */
+
+#undef DEBUG
+
+#include <linux/config.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/irq.h>
+#include <linux/smp.h>
+#include <linux/interrupt.h>
+#include <linux/bootmem.h>
+#include <linux/spinlock.h>
+#include <linux/pci.h>
+
+#include <asm/ptrace.h>
+#include <asm/signal.h>
+#include <asm/io.h>
+#include <asm/pgtable.h>
+#include <asm/irq.h>
+#include <asm/machdep.h>
+#include <asm/mpic.h>
+#include <asm/smp.h>
+
+#ifdef DEBUG
+#define DBG(fmt...) printk(fmt)
+#else
+#define DBG(fmt...)
+#endif
+
+static struct mpic *mpics;
+static struct mpic *mpic_primary;
+static DEFINE_SPINLOCK(mpic_lock);
+
+
+/*
+ * Register accessor functions
+ */
+
+
+static inline u32 _mpic_read(unsigned int be, volatile u32 __iomem *base,
+                            unsigned int reg)
+{
+        if (be)
+                return in_be32(base + (reg >> 2));
+        else
+                return in_le32(base + (reg >> 2));
+}
+
+static inline void _mpic_write(unsigned int be, volatile u32 __iomem *base,
+                              unsigned int reg, u32 value)
+{
+        if (be)
+                out_be32(base + (reg >> 2), value);
+        else
+                out_le32(base + (reg >> 2), value);
+}
+
+static inline u32 _mpic_ipi_read(struct mpic *mpic, unsigned int ipi)
+{
+        unsigned int be = (mpic->flags & MPIC_BIG_ENDIAN) != 0;
+        unsigned int offset = MPIC_GREG_IPI_VECTOR_PRI_0 + (ipi * 0x10);
+
+        if (mpic->flags & MPIC_BROKEN_IPI)
+                be = !be;
+        return _mpic_read(be, mpic->gregs, offset);
+}
+
+static inline void _mpic_ipi_write(struct mpic *mpic, unsigned int ipi, u32 value)
+{
+        unsigned int offset = MPIC_GREG_IPI_VECTOR_PRI_0 + (ipi * 0x10);
+
+        _mpic_write(mpic->flags & MPIC_BIG_ENDIAN, mpic->gregs, offset, value);
+}
+
+static inline u32 _mpic_cpu_read(struct mpic *mpic, unsigned int reg)
+{
+        unsigned int cpu = 0;
+
+        if (mpic->flags & MPIC_PRIMARY)
+                cpu = hard_smp_processor_id();
+
+        return _mpic_read(mpic->flags & MPIC_BIG_ENDIAN, mpic->cpuregs[cpu], reg);
+}
+
+static inline void _mpic_cpu_write(struct mpic *mpic, unsigned int reg, u32 value)
+{
+        unsigned int cpu = 0;
+
+        if (mpic->flags & MPIC_PRIMARY)
+                cpu = hard_smp_processor_id();
+
+        _mpic_write(mpic->flags & MPIC_BIG_ENDIAN, mpic->cpuregs[cpu], reg, value);
+}
+
+static inline u32 _mpic_irq_read(struct mpic *mpic, unsigned int src_no, unsigned int reg)
+{
+        unsigned int    isu = src_no >> mpic->isu_shift;
+        unsigned int    idx = src_no & mpic->isu_mask;
+
+        return _mpic_read(mpic->flags & MPIC_BIG_ENDIAN, mpic->isus[isu],
+                          reg + (idx * MPIC_IRQ_STRIDE));
+}
+
+static inline void _mpic_irq_write(struct mpic *mpic, unsigned int src_no,
+                                   unsigned int reg, u32 value)
+{
+        unsigned int    isu = src_no >> mpic->isu_shift;
+        unsigned int    idx = src_no & mpic->isu_mask;
+
+        _mpic_write(mpic->flags & MPIC_BIG_ENDIAN, mpic->isus[isu],
+                    reg + (idx * MPIC_IRQ_STRIDE), value);
+}
+
+#define mpic_read(b,r)          _mpic_read(mpic->flags & MPIC_BIG_ENDIAN,(b),(r))
+#define mpic_write(b,r,v)       _mpic_write(mpic->flags & MPIC_BIG_ENDIAN,(b),(r),(v))
+#define mpic_ipi_read(i)        _mpic_ipi_read(mpic,(i))
+#define mpic_ipi_write(i,v)     _mpic_ipi_write(mpic,(i),(v))
+#define mpic_cpu_read(i)        _mpic_cpu_read(mpic,(i))
+#define mpic_cpu_write(i,v)     _mpic_cpu_write(mpic,(i),(v))
+#define mpic_irq_read(s,r)      _mpic_irq_read(mpic,(s),(r))
+#define mpic_irq_write(s,r,v)   _mpic_irq_write(mpic,(s),(r),(v))
+
+
+/*
+ * Low level utility functions
+ */
+
+
+
+/* Check if we have one of those nice broken MPICs with a flipped endian on
+ * reads from IPI registers
+ */
+static void __init mpic_test_broken_ipi(struct mpic *mpic)
+{
+        u32 r;
+
+        mpic_write(mpic->gregs, MPIC_GREG_IPI_VECTOR_PRI_0, MPIC_VECPRI_MASK);
+        r = mpic_read(mpic->gregs, MPIC_GREG_IPI_VECTOR_PRI_0);
+
+        if (r == le32_to_cpu(MPIC_VECPRI_MASK)) {
+                printk(KERN_INFO "mpic: Detected reversed IPI registers\n");
+                mpic->flags |= MPIC_BROKEN_IPI;
+        }
+}
+
+#ifdef CONFIG_MPIC_BROKEN_U3
+
+/* Test if an interrupt is sourced from HyperTransport (used on broken U3s)
+ * to force the edge setting on the MPIC and do the ack workaround.
+ */
+static inline int mpic_is_ht_interrupt(struct mpic *mpic, unsigned int source_no)
+{
+        if (source_no >= 128 || !mpic->fixups)
+                return 0;
+        return mpic->fixups[source_no].base != NULL;
+}
+
+static inline void mpic_apic_end_irq(struct mpic *mpic, unsigned int source_no)
+{
+        struct mpic_irq_fixup *fixup = &mpic->fixups[source_no];
+        u32 tmp;
+
+        spin_lock(&mpic->fixup_lock);
+        writeb(0x11 + 2 * fixup->irq, fixup->base);
+        tmp = readl(fixup->base + 2);
+        writel(tmp | 0x80000000ul, fixup->base + 2);
+        /* config writes shouldn't be posted but let's be safe ... */
+        (void)readl(fixup->base + 2);
+        spin_unlock(&mpic->fixup_lock);
+}
+
+
+static void __init mpic_amd8111_read_irq(struct mpic *mpic, u8 __iomem *devbase)
+{
+        int i, irq;
+        u32 tmp;
+
+        printk(KERN_INFO "mpic:    - Workarounds on AMD 8111 @ %p\n", devbase);
+
+        for (i=0; i < 24; i++) {
+                writeb(0x10 + 2*i, devbase + 0xf2);
+                tmp = readl(devbase + 0xf4);
+                if ((tmp & 0x1) || !(tmp & 0x20))
+                        continue;
+                irq = (tmp >> 16) & 0xff;
+                mpic->fixups[irq].irq = i;
+                mpic->fixups[irq].base = devbase + 0xf2;
+        }
+}
+ 
+static void __init mpic_amd8131_read_irq(struct mpic *mpic, u8 __iomem *devbase)
+{
+        int i, irq;
+        u32 tmp;
+
+        printk(KERN_INFO "mpic:    - Workarounds on AMD 8131 @ %p\n", devbase);
+
+        for (i=0; i < 4; i++) {
+                writeb(0x10 + 2*i, devbase + 0xba);
+                tmp = readl(devbase + 0xbc);
+                if ((tmp & 0x1) || !(tmp & 0x20))
+                        continue;
+                irq = (tmp >> 16) & 0xff;
+                mpic->fixups[irq].irq = i;
+                mpic->fixups[irq].base = devbase + 0xba;
+        }
+}
+ 
+static void __init mpic_scan_ioapics(struct mpic *mpic)
+{
+        unsigned int devfn;
+        u8 __iomem *cfgspace;
+
+        printk(KERN_INFO "mpic: Setting up IO-APICs workarounds for U3\n");
+
+        /* Allocate fixups array */
+        mpic->fixups = alloc_bootmem(128 * sizeof(struct mpic_irq_fixup));
+        BUG_ON(mpic->fixups == NULL);
+        memset(mpic->fixups, 0, 128 * sizeof(struct mpic_irq_fixup));
+
+        /* Init spinlock */
+        spin_lock_init(&mpic->fixup_lock);
+
+        /* Map u3 config space. We assume all IO-APICs are on the primary bus
+         * and slot will never be above "0xf" so we only need to map 32k
+         */
+        cfgspace = (unsigned char __iomem *)ioremap(0xf2000000, 0x8000);
+        BUG_ON(cfgspace == NULL);
+
+        /* Now we scan all slots. We do a very quick scan, we read the header type,
+         * vendor ID and device ID only, that's plenty enough
+         */
+        for (devfn = 0; devfn < PCI_DEVFN(0x10,0); devfn ++) {
+                u8 __iomem *devbase = cfgspace + (devfn << 8);
+                u8 hdr_type = readb(devbase + PCI_HEADER_TYPE);
+                u32 l = readl(devbase + PCI_VENDOR_ID);
+                u16 vendor_id, device_id;
+                int multifunc = 0;
+
+                DBG("devfn %x, l: %x\n", devfn, l);
+
+                /* If no device, skip */
+                if (l == 0xffffffff || l == 0x00000000 ||
+                    l == 0x0000ffff || l == 0xffff0000)
+                        goto next;
+
+                /* Check if it's a multifunction device (only really used
+                 * to function 0 though
+                 */
+                multifunc = !!(hdr_type & 0x80);
+                vendor_id = l & 0xffff;
+                device_id = (l >> 16) & 0xffff;
+
+                /* If a known device, go to fixup setup code */
+                if (vendor_id == PCI_VENDOR_ID_AMD && device_id == 0x7460)
+                        mpic_amd8111_read_irq(mpic, devbase);
+                if (vendor_id == PCI_VENDOR_ID_AMD && device_id == 0x7450)
+                        mpic_amd8131_read_irq(mpic, devbase);
+        next:
+                /* next device, if function 0 */
+                if ((PCI_FUNC(devfn) == 0) && !multifunc)
+                        devfn += 7;
+        }
+}
+
+#endif /* CONFIG_MPIC_BROKEN_U3 */
+
+
+/* Find an mpic associated with a given linux interrupt */
+static struct mpic *mpic_find(unsigned int irq, unsigned int *is_ipi)
+{
+        struct mpic *mpic = mpics;
+
+        while(mpic) {
+                /* search IPIs first since they may override the main interrupts */
+                if (irq >= mpic->ipi_offset && irq < (mpic->ipi_offset + 4)) {
+                        if (is_ipi)
+                                *is_ipi = 1;
+                        return mpic;
+                }
+                if (irq >= mpic->irq_offset &&
+                    irq < (mpic->irq_offset + mpic->irq_count)) {
+                        if (is_ipi)
+                                *is_ipi = 0;
+                        return mpic;
+                }
+                mpic = mpic -> next;
+        }
+        return NULL;
+}
+
+/* Convert a cpu mask from logical to physical cpu numbers. */
+static inline u32 mpic_physmask(u32 cpumask)
+{
+        int i;
+        u32 mask = 0;
+
+        for (i = 0; i < NR_CPUS; ++i, cpumask >>= 1)
+                mask |= (cpumask & 1) << get_hard_smp_processor_id(i);
+        return mask;
+}
+
+#ifdef CONFIG_SMP
+/* Get the mpic structure from the IPI number */
+static inline struct mpic * mpic_from_ipi(unsigned int ipi)
+{
+        return container_of(irq_desc[ipi].handler, struct mpic, hc_ipi);
+}
+#endif
+
+/* Get the mpic structure from the irq number */
+static inline struct mpic * mpic_from_irq(unsigned int irq)
+{
+        return container_of(irq_desc[irq].handler, struct mpic, hc_irq);
+}
+
+/* Send an EOI */
+static inline void mpic_eoi(struct mpic *mpic)
+{
+        mpic_cpu_write(MPIC_CPU_EOI, 0);
+        (void)mpic_cpu_read(MPIC_CPU_WHOAMI);
+}
+
+#ifdef CONFIG_SMP
+static irqreturn_t mpic_ipi_action(int irq, void *dev_id, struct pt_regs *regs)
+{
+        struct mpic *mpic = dev_id;
+
+        smp_message_recv(irq - mpic->ipi_offset, regs);
+        return IRQ_HANDLED;
+}
+#endif /* CONFIG_SMP */
+
+/*
+ * Linux descriptor level callbacks
+ */
+
+
+static void mpic_enable_irq(unsigned int irq)
+{
+        unsigned int loops = 100000;
+        struct mpic *mpic = mpic_from_irq(irq);
+        unsigned int src = irq - mpic->irq_offset;
+
+        DBG("%s: enable_irq: %d (src %d)\n", mpic->name, irq, src);
+
+        mpic_irq_write(src, MPIC_IRQ_VECTOR_PRI,
+                       mpic_irq_read(src, MPIC_IRQ_VECTOR_PRI) & ~MPIC_VECPRI_MASK);
+
+        /* make sure mask gets to controller before we return to user */
+        do {
+                if (!loops--) {
+                        printk(KERN_ERR "mpic_enable_irq timeout\n");
+                        break;
+                }
+        } while(mpic_irq_read(src, MPIC_IRQ_VECTOR_PRI) & MPIC_VECPRI_MASK);    
+}
+
+static void mpic_disable_irq(unsigned int irq)
+{
+        unsigned int loops = 100000;
+        struct mpic *mpic = mpic_from_irq(irq);
+        unsigned int src = irq - mpic->irq_offset;
+
+        DBG("%s: disable_irq: %d (src %d)\n", mpic->name, irq, src);
+
+        mpic_irq_write(src, MPIC_IRQ_VECTOR_PRI,
+                       mpic_irq_read(src, MPIC_IRQ_VECTOR_PRI) | MPIC_VECPRI_MASK);
+
+        /* make sure mask gets to controller before we return to user */
+        do {
+                if (!loops--) {
+                        printk(KERN_ERR "mpic_enable_irq timeout\n");
+                        break;
+                }
+        } while(!(mpic_irq_read(src, MPIC_IRQ_VECTOR_PRI) & MPIC_VECPRI_MASK));
+}
+
+static void mpic_end_irq(unsigned int irq)
+{
+        struct mpic *mpic = mpic_from_irq(irq);
+
+        DBG("%s: end_irq: %d\n", mpic->name, irq);
+
+        /* We always EOI on end_irq() even for edge interrupts since that
+         * should only lower the priority, the MPIC should have properly
+         * latched another edge interrupt coming in anyway
+         */
+
+#ifdef CONFIG_MPIC_BROKEN_U3
+        if (mpic->flags & MPIC_BROKEN_U3) {
+                unsigned int src = irq - mpic->irq_offset;
+                if (mpic_is_ht_interrupt(mpic, src))
+                        mpic_apic_end_irq(mpic, src);
+        }
+#endif /* CONFIG_MPIC_BROKEN_U3 */
+
+        mpic_eoi(mpic);
+}
+
+#ifdef CONFIG_SMP
+
+static void mpic_enable_ipi(unsigned int irq)
+{
+        struct mpic *mpic = mpic_from_ipi(irq);
+        unsigned int src = irq - mpic->ipi_offset;
+
+        DBG("%s: enable_ipi: %d (ipi %d)\n", mpic->name, irq, src);
+        mpic_ipi_write(src, mpic_ipi_read(src) & ~MPIC_VECPRI_MASK);
+}
+
+static void mpic_disable_ipi(unsigned int irq)
+{
+        /* NEVER disable an IPI... that's just plain wrong! */
+}
+
+static void mpic_end_ipi(unsigned int irq)
+{
+        struct mpic *mpic = mpic_from_ipi(irq);
+
+        /*
+         * IPIs are marked IRQ_PER_CPU. This has the side effect of
+         * preventing the IRQ_PENDING/IRQ_INPROGRESS logic from
+         * applying to them. We EOI them late to avoid re-entering.
+         * We mark IPI's with SA_INTERRUPT as they must run with
+         * irqs disabled.
+         */
+        mpic_eoi(mpic);
+}
+
+#endif /* CONFIG_SMP */
+
+static void mpic_set_affinity(unsigned int irq, cpumask_t cpumask)
+{
+        struct mpic *mpic = mpic_from_irq(irq);
+
+        cpumask_t tmp;
+
+        cpus_and(tmp, cpumask, cpu_online_map);
+
+        mpic_irq_write(irq - mpic->irq_offset, MPIC_IRQ_DESTINATION,
+                       mpic_physmask(cpus_addr(tmp)[0]));       
+}
+
+
+/*
+ * Exported functions
+ */
+
+
+struct mpic * __init mpic_alloc(unsigned long phys_addr,
+                                unsigned int flags,
+                                unsigned int isu_size,
+                                unsigned int irq_offset,
+                                unsigned int irq_count,
+                                unsigned int ipi_offset,
+                                unsigned char *senses,
+                                unsigned int senses_count,
+                                const char *name)
+{
+        struct mpic     *mpic;
+        u32             reg;
+        const char      *vers;
+        int             i;
+
+        mpic = alloc_bootmem(sizeof(struct mpic));
+        if (mpic == NULL)
+                return NULL;
+        
+
+        memset(mpic, 0, sizeof(struct mpic));
+        mpic->name = name;
+
+        mpic->hc_irq.typename = name;
+        mpic->hc_irq.enable = mpic_enable_irq;
+        mpic->hc_irq.disable = mpic_disable_irq;
+        mpic->hc_irq.end = mpic_end_irq;
+        if (flags & MPIC_PRIMARY)
+                mpic->hc_irq.set_affinity = mpic_set_affinity;
+#ifdef CONFIG_SMP
+        mpic->hc_ipi.typename = name;
+        mpic->hc_ipi.enable = mpic_enable_ipi;
+        mpic->hc_ipi.disable = mpic_disable_ipi;
+        mpic->hc_ipi.end = mpic_end_ipi;
+#endif /* CONFIG_SMP */
+
+        mpic->flags = flags;
+        mpic->isu_size = isu_size;
+        mpic->irq_offset = irq_offset;
+        mpic->irq_count = irq_count;
+        mpic->ipi_offset = ipi_offset;
+        mpic->num_sources = 0; /* so far */
+        mpic->senses = senses;
+        mpic->senses_count = senses_count;
+
+        /* Map the global registers */
+        mpic->gregs = ioremap(phys_addr + MPIC_GREG_BASE, 0x1000);
+        mpic->tmregs = mpic->gregs + (MPIC_TIMER_BASE >> 2);
+        BUG_ON(mpic->gregs == NULL);
+
+        /* Reset */
+        if (flags & MPIC_WANTS_RESET) {
+                mpic_write(mpic->gregs, MPIC_GREG_GLOBAL_CONF_0,
+                           mpic_read(mpic->gregs, MPIC_GREG_GLOBAL_CONF_0)
+                           | MPIC_GREG_GCONF_RESET);
+                while( mpic_read(mpic->gregs, MPIC_GREG_GLOBAL_CONF_0)
+                       & MPIC_GREG_GCONF_RESET)
+                        mb();
+        }
+
+        /* Read feature register, calculate num CPUs and, for non-ISU
+         * MPICs, num sources as well. On ISU MPICs, sources are counted
+         * as ISUs are added
+         */
+        reg = mpic_read(mpic->gregs, MPIC_GREG_FEATURE_0);
+        mpic->num_cpus = ((reg & MPIC_GREG_FEATURE_LAST_CPU_MASK)
+                          >> MPIC_GREG_FEATURE_LAST_CPU_SHIFT) + 1;
+        if (isu_size == 0)
+                mpic->num_sources = ((reg & MPIC_GREG_FEATURE_LAST_SRC_MASK)
+                                     >> MPIC_GREG_FEATURE_LAST_SRC_SHIFT) + 1;
+
+        /* Map the per-CPU registers */
+        for (i = 0; i < mpic->num_cpus; i++) {
+                mpic->cpuregs[i] = ioremap(phys_addr + MPIC_CPU_BASE +
+                                           i * MPIC_CPU_STRIDE, 0x1000);
+                BUG_ON(mpic->cpuregs[i] == NULL);
+        }
+
+        /* Initialize main ISU if none provided */
+        if (mpic->isu_size == 0) {
+                mpic->isu_size = mpic->num_sources;
+                mpic->isus[0] = ioremap(phys_addr + MPIC_IRQ_BASE,
+                                        MPIC_IRQ_STRIDE * mpic->isu_size);
+                BUG_ON(mpic->isus[0] == NULL);
+        }
+        mpic->isu_shift = 1 + __ilog2(mpic->isu_size - 1);
+        mpic->isu_mask = (1 << mpic->isu_shift) - 1;
+
+        /* Display version */
+        switch (reg & MPIC_GREG_FEATURE_VERSION_MASK) {
+        case 1:
+                vers = "1.0";
+                break;
+        case 2:
+                vers = "1.2";
+                break;
+        case 3:
+                vers = "1.3";
+                break;
+        default:
+                vers = "<unknown>";
+                break;
+        }
+        printk(KERN_INFO "mpic: Setting up MPIC \"%s\" version %s at %lx, max %d CPUs\n",
+               name, vers, phys_addr, mpic->num_cpus);
+        printk(KERN_INFO "mpic: ISU size: %d, shift: %d, mask: %x\n", mpic->isu_size,
+               mpic->isu_shift, mpic->isu_mask);
+
+        mpic->next = mpics;
+        mpics = mpic;
+
+        if (flags & MPIC_PRIMARY)
+                mpic_primary = mpic;
+
+        return mpic;
+}
+
+void __init mpic_assign_isu(struct mpic *mpic, unsigned int isu_num,
+                            unsigned long phys_addr)
+{
+        unsigned int isu_first = isu_num * mpic->isu_size;
+
+        BUG_ON(isu_num >= MPIC_MAX_ISU);
+
+        mpic->isus[isu_num] = ioremap(phys_addr, MPIC_IRQ_STRIDE * mpic->isu_size);
+        if ((isu_first + mpic->isu_size) > mpic->num_sources)
+                mpic->num_sources = isu_first + mpic->isu_size;
+}
+
+void __init mpic_setup_cascade(unsigned int irq, mpic_cascade_t handler,
+                               void *data)
+{
+        struct mpic *mpic = mpic_find(irq, NULL);
+        unsigned long flags;
+
+        /* Synchronization here is a bit dodgy, so don't try to replace cascade
+         * interrupts on the fly too often ... but normally it's set up at boot.
+         */
+        spin_lock_irqsave(&mpic_lock, flags);
+        if (mpic->cascade)             
+                mpic_disable_irq(mpic->cascade_vec + mpic->irq_offset);
+        mpic->cascade = NULL;
+        wmb();
+        mpic->cascade_vec = irq - mpic->irq_offset;
+        mpic->cascade_data = data;
+        wmb();
+        mpic->cascade = handler;
+        mpic_enable_irq(irq);
+        spin_unlock_irqrestore(&mpic_lock, flags);
+}
+
+void __init mpic_init(struct mpic *mpic)
+{
+        int i;
+
+        BUG_ON(mpic->num_sources == 0);
+
+        printk(KERN_INFO "mpic: Initializing for %d sources\n", mpic->num_sources);
+
+        /* Set current processor priority to max */
+        mpic_cpu_write(MPIC_CPU_CURRENT_TASK_PRI, 0xf);
+
+        /* Initialize timers: just disable them all */
+        for (i = 0; i < 4; i++) {
+                mpic_write(mpic->tmregs,
+                           i * MPIC_TIMER_STRIDE + MPIC_TIMER_DESTINATION, 0);
+                mpic_write(mpic->tmregs,
+                           i * MPIC_TIMER_STRIDE + MPIC_TIMER_VECTOR_PRI,
+                           MPIC_VECPRI_MASK |
+                           (MPIC_VEC_TIMER_0 + i));
+        }
+
+        /* Initialize IPIs to our reserved vectors and mark them disabled for now */
+        mpic_test_broken_ipi(mpic);
+        for (i = 0; i < 4; i++) {
+                mpic_ipi_write(i,
+                               MPIC_VECPRI_MASK |
+                               (10 << MPIC_VECPRI_PRIORITY_SHIFT) |
+                               (MPIC_VEC_IPI_0 + i));
+#ifdef CONFIG_SMP
+                if (!(mpic->flags & MPIC_PRIMARY))
+                        continue;
+                irq_desc[mpic->ipi_offset+i].status |= IRQ_PER_CPU;
+                irq_desc[mpic->ipi_offset+i].handler = &mpic->hc_ipi;
+                
+#endif /* CONFIG_SMP */
+        }
+
+        /* Initialize interrupt sources */
+        if (mpic->irq_count == 0)
+                mpic->irq_count = mpic->num_sources;
+
+#ifdef CONFIG_MPIC_BROKEN_U3
+        /* Do the ioapic fixups on U3 broken mpic */
+        DBG("MPIC flags: %x\n", mpic->flags);
+        if ((mpic->flags & MPIC_BROKEN_U3) && (mpic->flags & MPIC_PRIMARY))
+                mpic_scan_ioapics(mpic);
+#endif /* CONFIG_MPIC_BROKEN_U3 */
+
+        for (i = 0; i < mpic->num_sources; i++) {
+                /* start with vector = source number, and masked */
+                u32 vecpri = MPIC_VECPRI_MASK | i | (8 << MPIC_VECPRI_PRIORITY_SHIFT);
+                int level = 0;
+                
+                /* if it's an IPI, we skip it */
+                if ((mpic->irq_offset + i) >= (mpic->ipi_offset + i) &&
+                    (mpic->irq_offset + i) <  (mpic->ipi_offset + i + 4))
+                        continue;
+
+                /* do senses munging */
+                if (mpic->senses && i < mpic->senses_count) {
+                        if (mpic->senses[i] & IRQ_SENSE_LEVEL)
+                                vecpri |= MPIC_VECPRI_SENSE_LEVEL;
+                        if (mpic->senses[i] & IRQ_POLARITY_POSITIVE)
+                                vecpri |= MPIC_VECPRI_POLARITY_POSITIVE;
+                } else
+                        vecpri |= MPIC_VECPRI_SENSE_LEVEL;
+
+                /* remember if it was a level interrupts */
+                level = (vecpri & MPIC_VECPRI_SENSE_LEVEL);
+
+                /* deal with broken U3 */
+                if (mpic->flags & MPIC_BROKEN_U3) {
+#ifdef CONFIG_MPIC_BROKEN_U3
+                        if (mpic_is_ht_interrupt(mpic, i)) {
+                                vecpri &= ~(MPIC_VECPRI_SENSE_MASK |
+                                            MPIC_VECPRI_POLARITY_MASK);
+                                vecpri |= MPIC_VECPRI_POLARITY_POSITIVE;
+                        }
+#else
+                        printk(KERN_ERR "mpic: BROKEN_U3 set, but CONFIG doesn't match\n");
+#endif
+                }
+
+                DBG("setup source %d, vecpri: %08x, level: %d\n", i, vecpri,
+                    (level != 0));
+
+                /* init hw */
+                mpic_irq_write(i, MPIC_IRQ_VECTOR_PRI, vecpri);
+                mpic_irq_write(i, MPIC_IRQ_DESTINATION,
+                               1 << hard_smp_processor_id());
+
+                /* init linux descriptors */
+                if (i < mpic->irq_count) {
+                        irq_desc[mpic->irq_offset+i].status = level ? IRQ_LEVEL : 0;
+                        irq_desc[mpic->irq_offset+i].handler = &mpic->hc_irq;
+                }
+        }
+        
+        /* Init spurrious vector */
+        mpic_write(mpic->gregs, MPIC_GREG_SPURIOUS, MPIC_VEC_SPURRIOUS);
+
+        /* Disable 8259 passthrough */
+        mpic_write(mpic->gregs, MPIC_GREG_GLOBAL_CONF_0,
+                   mpic_read(mpic->gregs, MPIC_GREG_GLOBAL_CONF_0)
+                   | MPIC_GREG_GCONF_8259_PTHROU_DIS);
+
+        /* Set current processor priority to 0 */
+        mpic_cpu_write(MPIC_CPU_CURRENT_TASK_PRI, 0);
+}
+
+
+
+void mpic_irq_set_priority(unsigned int irq, unsigned int pri)
+{
+        int is_ipi;
+        struct mpic *mpic = mpic_find(irq, &is_ipi);
+        unsigned long flags;
+        u32 reg;
+
+        spin_lock_irqsave(&mpic_lock, flags);
+        if (is_ipi) {
+                reg = mpic_ipi_read(irq - mpic->ipi_offset) & MPIC_VECPRI_PRIORITY_MASK;
+                mpic_ipi_write(irq - mpic->ipi_offset,
+                               reg | (pri << MPIC_VECPRI_PRIORITY_SHIFT));
+        } else {
+                reg = mpic_irq_read(irq - mpic->irq_offset, MPIC_IRQ_VECTOR_PRI)
+                        & MPIC_VECPRI_PRIORITY_MASK;
+                mpic_irq_write(irq - mpic->irq_offset, MPIC_IRQ_VECTOR_PRI,
+                               reg | (pri << MPIC_VECPRI_PRIORITY_SHIFT));
+        }
+        spin_unlock_irqrestore(&mpic_lock, flags);
+}
+
+unsigned int mpic_irq_get_priority(unsigned int irq)
+{
+        int is_ipi;
+        struct mpic *mpic = mpic_find(irq, &is_ipi);
+        unsigned long flags;
+        u32 reg;
+
+        spin_lock_irqsave(&mpic_lock, flags);
+        if (is_ipi)
+                reg = mpic_ipi_read(irq - mpic->ipi_offset);
+        else
+                reg = mpic_irq_read(irq - mpic->irq_offset, MPIC_IRQ_VECTOR_PRI);
+        spin_unlock_irqrestore(&mpic_lock, flags);
+        return (reg & MPIC_VECPRI_PRIORITY_MASK) >> MPIC_VECPRI_PRIORITY_SHIFT;
+}
+
+void mpic_setup_this_cpu(void)
+{
+#ifdef CONFIG_SMP
+        struct mpic *mpic = mpic_primary;
+        unsigned long flags;
+        u32 msk = 1 << hard_smp_processor_id();
+        unsigned int i;
+
+        BUG_ON(mpic == NULL);
+
+        DBG("%s: setup_this_cpu(%d)\n", mpic->name, hard_smp_processor_id());
+
+        spin_lock_irqsave(&mpic_lock, flags);
+
+        /* let the mpic know we want intrs. default affinity is 0xffffffff
+         * until changed via /proc. That's how it's done on x86. If we want
+         * it differently, then we should make sure we also change the default
+         * values of irq_affinity in irq.c.
+         */
+        if (distribute_irqs) {
+                for (i = 0; i < mpic->num_sources ; i++)
+                        mpic_irq_write(i, MPIC_IRQ_DESTINATION,
+                                mpic_irq_read(i, MPIC_IRQ_DESTINATION) | msk);
+        }
+
+        /* Set current processor priority to 0 */
+        mpic_cpu_write(MPIC_CPU_CURRENT_TASK_PRI, 0);
+
+        spin_unlock_irqrestore(&mpic_lock, flags);
+#endif /* CONFIG_SMP */
+}
+
+int mpic_cpu_get_priority(void)
+{
+        struct mpic *mpic = mpic_primary;
+
+        return mpic_cpu_read(MPIC_CPU_CURRENT_TASK_PRI);
+}
+
+void mpic_cpu_set_priority(int prio)
+{
+        struct mpic *mpic = mpic_primary;
+
+        prio &= MPIC_CPU_TASKPRI_MASK;
+        mpic_cpu_write(MPIC_CPU_CURRENT_TASK_PRI, prio);
+}
+
+/*
+ * XXX: someone who knows mpic should check this.
+ * do we need to eoi the ipi including for kexec cpu here (see xics comments)?
+ * or can we reset the mpic in the new kernel?
+ */
+void mpic_teardown_this_cpu(int secondary)
+{
+        struct mpic *mpic = mpic_primary;
+        unsigned long flags;
+        u32 msk = 1 << hard_smp_processor_id();
+        unsigned int i;
+
+        BUG_ON(mpic == NULL);
+
+        DBG("%s: teardown_this_cpu(%d)\n", mpic->name, hard_smp_processor_id());
+        spin_lock_irqsave(&mpic_lock, flags);
+
+        /* let the mpic know we don't want intrs.  */
+        for (i = 0; i < mpic->num_sources ; i++)
+                mpic_irq_write(i, MPIC_IRQ_DESTINATION,
+                        mpic_irq_read(i, MPIC_IRQ_DESTINATION) & ~msk);
+
+        /* Set current processor priority to max */
+        mpic_cpu_write(MPIC_CPU_CURRENT_TASK_PRI, 0xf);
+
+        spin_unlock_irqrestore(&mpic_lock, flags);
+}
+
+
+void mpic_send_ipi(unsigned int ipi_no, unsigned int cpu_mask)
+{
+        struct mpic *mpic = mpic_primary;
+
+        BUG_ON(mpic == NULL);
+
+        DBG("%s: send_ipi(ipi_no: %d)\n", mpic->name, ipi_no);
+
+        mpic_cpu_write(MPIC_CPU_IPI_DISPATCH_0 + ipi_no * 0x10,
+                       mpic_physmask(cpu_mask & cpus_addr(cpu_online_map)[0]));
+}
+
+int mpic_get_one_irq(struct mpic *mpic, struct pt_regs *regs)
+{
+        u32 irq;
+
+        irq = mpic_cpu_read(MPIC_CPU_INTACK) & MPIC_VECPRI_VECTOR_MASK;
+        DBG("%s: get_one_irq(): %d\n", mpic->name, irq);
+
+        if (mpic->cascade && irq == mpic->cascade_vec) {
+                DBG("%s: cascading ...\n", mpic->name);
+                irq = mpic->cascade(regs, mpic->cascade_data);
+                mpic_eoi(mpic);
+                return irq;
+        }
+        if (unlikely(irq == MPIC_VEC_SPURRIOUS))
+                return -1;
+        if (irq < MPIC_VEC_IPI_0) 
+                return irq + mpic->irq_offset;
+        DBG("%s: ipi %d !\n", mpic->name, irq - MPIC_VEC_IPI_0);
+        return irq - MPIC_VEC_IPI_0 + mpic->ipi_offset;
+}
+
+int mpic_get_irq(struct pt_regs *regs)
+{
+        struct mpic *mpic = mpic_primary;
+
+        BUG_ON(mpic == NULL);
+
+        return mpic_get_one_irq(mpic, regs);
+}
+
+
+#ifdef CONFIG_SMP
+void mpic_request_ipis(void)
+{
+        struct mpic *mpic = mpic_primary;
+
+        BUG_ON(mpic == NULL);
+        
+        printk("requesting IPIs ... \n");
+
+        /* IPIs are marked SA_INTERRUPT as they must run with irqs disabled */
+        request_irq(mpic->ipi_offset+0, mpic_ipi_action, SA_INTERRUPT,
+                    "IPI0 (call function)", mpic);
+        request_irq(mpic->ipi_offset+1, mpic_ipi_action, SA_INTERRUPT,
+                   "IPI1 (reschedule)", mpic);
+        request_irq(mpic->ipi_offset+2, mpic_ipi_action, SA_INTERRUPT,
+                   "IPI2 (unused)", mpic);
+        request_irq(mpic->ipi_offset+3, mpic_ipi_action, SA_INTERRUPT,
+                   "IPI3 (debugger break)", mpic);
+
+        printk("IPIs requested... \n");
+}
+#endif /* CONFIG_SMP */