[PATCH] powerpc: Experimental support for new G5 Macs (#2)

This adds some very basic support for the new machines, including the
Quad G5 (tested), and other new dual core based machines and iMac G5
iSight (untested). This is still experimental !  There is no thermal
control yet, there is no proper handing of MSIs, etc.. but it
boots, I have all 4 cores up on my machine. Compared to the previous
version of this patch, this one adds DART IOMMU support for the U4
chipset and thus should work fine on setups with more than 2Gb of RAM.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

4 files changed, 287 insertions, 128 deletions

diff --git a/arch/powerpc/sysdev/Makefile b/arch/powerpc/sysdev/Makefile
index b3e3636a57b0..14b9abde2d27 100644
--- a/arch/powerpc/sysdev/Makefile
+++ b/arch/powerpc/sysdev/Makefile
@@ -4,6 +4,6 @@ obj-$(CONFIG_PPC_I8259)		+= i8259.o
 obj-$(CONFIG_PPC_MPC106)        += grackle.o
 obj-$(CONFIG_BOOKE)             += dcr.o
 obj-$(CONFIG_40x)               += dcr.o
-obj-$(CONFIG_U3_DART)           += u3_iommu.o
+obj-$(CONFIG_U3_DART)           += dart_iommu.o
 obj-$(CONFIG_MMIO_NVRAM)        += mmio_nvram.o
 obj-$(CONFIG_83xx)              += ipic.o
diff --git a/arch/powerpc/sysdev/dart.h b/arch/powerpc/sysdev/dart.h
index 33ed9ed7fc1e..c2d05763ccbe 100644
--- a/arch/powerpc/sysdev/dart.h
+++ b/arch/powerpc/sysdev/dart.h
@@ -20,29 +20,44 @@
 #define _POWERPC_SYSDEV_DART_H
 
 
-/* physical base of DART registers */
-#define DART_BASE        0xf8033000UL
-
 /* Offset from base to control register */
-#define DARTCNTL   0
+#define DART_CNTL       0
+
 /* Offset from base to exception register */
-#define DARTEXCP   0x10
+#define DART_EXCP_U3    0x10
 /* Offset from base to TLB tag registers */
-#define DARTTAG    0x1000
+#define DART_TAGS_U3    0x1000
 
+/* U4 registers */
+#define DART_BASE_U4    0x10
+#define DART_SIZE_U4    0x20
+#define DART_EXCP_U4    0x30
+#define DART_TAGS_U4    0x1000
 
 /* Control Register fields */
 
-/* base address of table (pfn) */
-#define DARTCNTL_BASE_MASK    0xfffff
-#define DARTCNTL_BASE_SHIFT   12
+/* U3 registers */
+#define DART_CNTL_U3_BASE_MASK  0xfffff
+#define DART_CNTL_U3_BASE_SHIFT 12
+#define DART_CNTL_U3_FLUSHTLB   0x400
+#define DART_CNTL_U3_ENABLE     0x200
+#define DART_CNTL_U3_SIZE_MASK  0x1ff
+#define DART_CNTL_U3_SIZE_SHIFT 0
+
+/* U4 registers */
+#define DART_BASE_U4_BASE_MASK  0xffffff
+#define DART_BASE_U4_BASE_SHIFT 0
+#define DART_CNTL_U4_FLUSHTLB   0x20000000
+#define DART_CNTL_U4_ENABLE     0x80000000
+#define DART_SIZE_U4_SIZE_MASK  0x1fff
+#define DART_SIZE_U4_SIZE_SHIFT 0
+
+#define DART_REG(r)     (dart + ((r) >> 2))
+#define DART_IN(r)      (in_be32(DART_REG(r)))
+#define DART_OUT(r,v)   (out_be32(DART_REG(r), (v)))
 
-#define DARTCNTL_FLUSHTLB     0x400
-#define DARTCNTL_ENABLE       0x200
 
 /* size of table in pages */
-#define DARTCNTL_SIZE_MASK    0x1ff
-#define DARTCNTL_SIZE_SHIFT   0
 
 
 /* DART table fields */
diff --git a/arch/powerpc/sysdev/u3_iommu.c b/arch/powerpc/sysdev/dart_iommu.c
index 5c1a26a6d00c..df0dbdee762a 100644
--- a/arch/powerpc/sysdev/u3_iommu.c
+++ b/arch/powerpc/sysdev/dart_iommu.c
@@ -1,25 +1,27 @@
 /*
- * arch/powerpc/sysdev/u3_iommu.c
+ * arch/powerpc/sysdev/dart_iommu.c
  *
  * Copyright (C) 2004 Olof Johansson <olof@lixom.net>, IBM Corporation
+ * Copyright (C) 2005 Benjamin Herrenschmidt <benh@kernel.crashing.org>,
+ *                    IBM Corporation
  *
  * Based on pSeries_iommu.c:
  * Copyright (C) 2001 Mike Corrigan & Dave Engebretsen, IBM Corporation
  * Copyright (C) 2004 Olof Johansson <olof@lixom.net>, IBM Corporation
  *
- * Dynamic DMA mapping support, Apple U3 & IBM CPC925 "DART" iommu.
+ * Dynamic DMA mapping support, Apple U3, U4 & IBM CPC925 "DART" iommu.
+ *
  *
- * 
  * 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
@@ -57,21 +59,22 @@ static unsigned long dart_tablesize;
 static u32 *dart_vbase;
 
 /* Mapped base address for the dart */
-static unsigned int *dart; 
+static unsigned int *__iomem dart;
 
 /* Dummy val that entries are set to when unused */
 static unsigned int dart_emptyval;
 
-static struct iommu_table iommu_table_u3;
-static int iommu_table_u3_inited;
+static struct iommu_table iommu_table_dart;
+static int iommu_table_dart_inited;
 static int dart_dirty;
+static int dart_is_u4;
 
 #define DBG(...)
 
 static inline void dart_tlb_invalidate_all(void)
 {
         unsigned long l = 0;
-        unsigned int reg;
+        unsigned int reg, inv_bit;
         unsigned long limit;
 
         DBG("dart: flush\n");
@@ -81,29 +84,28 @@ static inline void dart_tlb_invalidate_all(void)
          *
          * Gotcha: Sometimes, the DART won't detect that the bit gets
          * set. If so, clear it and set it again.
-         */ 
+         */
 
         limit = 0;
 
+        inv_bit = dart_is_u4 ? DART_CNTL_U4_FLUSHTLB : DART_CNTL_U3_FLUSHTLB;
 retry:
-        reg = in_be32((unsigned int *)dart+DARTCNTL);
-        reg |= DARTCNTL_FLUSHTLB;
-        out_be32((unsigned int *)dart+DARTCNTL, reg);
-
         l = 0;
-        while ((in_be32((unsigned int *)dart+DARTCNTL) & DARTCNTL_FLUSHTLB) &&
-                l < (1L<<limit)) {
+        reg = DART_IN(DART_CNTL);
+        reg |= inv_bit;
+        DART_OUT(DART_CNTL, reg);
+
+        while ((DART_IN(DART_CNTL) & inv_bit) && l < (1L << limit))
                 l++;
-        }
-        if (l == (1L<<limit)) {
+        if (l == (1L << limit)) {
                 if (limit < 4) {
                         limit++;
-                        reg = in_be32((unsigned int *)dart+DARTCNTL);
-                        reg &= ~DARTCNTL_FLUSHTLB;
-                        out_be32((unsigned int *)dart+DARTCNTL, reg);
+                        reg = DART_IN(DART_CNTL);
+                        reg &= ~inv_bit;
+                        DART_OUT(DART_CNTL, reg);
                         goto retry;
                 } else
-                        panic("U3-DART: TLB did not flush after waiting a long "
+                        panic("DART: TLB did not flush after waiting a long "
                               "time. Buggy U3 ?");
         }
 }
@@ -115,7 +117,7 @@ static void dart_flush(struct iommu_table *tbl)
         dart_dirty = 0;
 }
 
-static void dart_build(struct iommu_table *tbl, long index, 
+static void dart_build(struct iommu_table *tbl, long index,
                        long npages, unsigned long uaddr,
                        enum dma_data_direction direction)
 {
@@ -128,7 +130,7 @@ static void dart_build(struct iommu_table *tbl, long index,
         npages <<= DART_PAGE_FACTOR;
 
         dp = ((unsigned int*)tbl->it_base) + index;
-        
+
         /* On U3, all memory is contigous, so we can move this
          * out of the loop.
          */
@@ -148,7 +150,7 @@ static void dart_build(struct iommu_table *tbl, long index,
 static void dart_free(struct iommu_table *tbl, long index, long npages)
 {
         unsigned int *dp;
-        
+
         /* We don't worry about flushing the TLB cache. The only drawback of
          * not doing it is that we won't catch buggy device drivers doing
          * bad DMAs, but then no 32-bit architecture ever does either.
@@ -160,7 +162,7 @@ static void dart_free(struct iommu_table *tbl, long index, long npages)
         npages <<= DART_PAGE_FACTOR;
 
         dp  = ((unsigned int *)tbl->it_base) + index;
-                
+
         while (npages--)
                 *(dp++) = dart_emptyval;
 }
@@ -168,20 +170,25 @@ static void dart_free(struct iommu_table *tbl, long index, long npages)
 
 static int dart_init(struct device_node *dart_node)
 {
-        unsigned int regword;
         unsigned int i;
-        unsigned long tmp;
+        unsigned long tmp, base, size;
+        struct resource r;
 
         if (dart_tablebase == 0 || dart_tablesize == 0) {
-                printk(KERN_INFO "U3-DART: table not allocated, using direct DMA\n");
+                printk(KERN_INFO "DART: table not allocated, using "
+                       "direct DMA\n");
                 return -ENODEV;
         }
 
+        if (of_address_to_resource(dart_node, 0, &r))
+                panic("DART: can't get register base ! ");
+
         /* Make sure nothing from the DART range remains in the CPU cache
          * from a previous mapping that existed before the kernel took
          * over
          */
-        flush_dcache_phys_range(dart_tablebase, dart_tablebase + dart_tablesize);
+        flush_dcache_phys_range(dart_tablebase,
+                                dart_tablebase + dart_tablesize);
 
         /* Allocate a spare page to map all invalid DART pages. We need to do
          * that to work around what looks like a problem with the HT bridge
@@ -189,21 +196,16 @@ static int dart_init(struct device_node *dart_node)
          */
         tmp = lmb_alloc(DART_PAGE_SIZE, DART_PAGE_SIZE);
         if (!tmp)
-                panic("U3-DART: Cannot allocate spare page!");
-        dart_emptyval = DARTMAP_VALID | ((tmp >> DART_PAGE_SHIFT) & DARTMAP_RPNMASK);
+                panic("DART: Cannot allocate spare page!");
+        dart_emptyval = DARTMAP_VALID | ((tmp >> DART_PAGE_SHIFT) &
+                                         DARTMAP_RPNMASK);
 
-        /* Map in DART registers. FIXME: Use device node to get base address */
-        dart = ioremap(DART_BASE, 0x7000);
+        /* Map in DART registers */
+        dart = ioremap(r.start, r.end - r.start + 1);
         if (dart == NULL)
-                panic("U3-DART: Cannot map registers!");
+                panic("DART: Cannot map registers!");
 
-        /* Set initial control register contents: table base, 
-         * table size and enable bit
-         */
-        regword = DARTCNTL_ENABLE | 
-                ((dart_tablebase >> DART_PAGE_SHIFT) << DARTCNTL_BASE_SHIFT) |
-                (((dart_tablesize >> DART_PAGE_SHIFT) & DARTCNTL_SIZE_MASK)
-                                 << DARTCNTL_SIZE_SHIFT);
+        /* Map in DART table */
         dart_vbase = ioremap(virt_to_abs(dart_tablebase), dart_tablesize);
 
         /* Fill initial table */
@@ -211,36 +213,50 @@ static int dart_init(struct device_node *dart_node)
                 dart_vbase[i] = dart_emptyval;
 
         /* Initialize DART with table base and enable it. */
-        out_be32((unsigned int *)dart, regword);
+        base = dart_tablebase >> DART_PAGE_SHIFT;
+        size = dart_tablesize >> DART_PAGE_SHIFT;
+        if (dart_is_u4) {
+                BUG_ON(size & ~DART_SIZE_U4_SIZE_MASK);
+                DART_OUT(DART_BASE_U4, base);
+                DART_OUT(DART_SIZE_U4, size);
+                DART_OUT(DART_CNTL, DART_CNTL_U4_ENABLE);
+        } else {
+                BUG_ON(size & ~DART_CNTL_U3_SIZE_MASK);
+                DART_OUT(DART_CNTL,
+                         DART_CNTL_U3_ENABLE |
+                         (base << DART_CNTL_U3_BASE_SHIFT) |
+                         (size << DART_CNTL_U3_SIZE_SHIFT));
+        }
 
         /* Invalidate DART to get rid of possible stale TLBs */
         dart_tlb_invalidate_all();
 
-        printk(KERN_INFO "U3/CPC925 DART IOMMU initialized\n");
+        printk(KERN_INFO "DART IOMMU initialized for %s type chipset\n",
+               dart_is_u4 ? "U4" : "U3");
 
         return 0;
 }
 
-static void iommu_table_u3_setup(void)
+static void iommu_table_dart_setup(void)
 {
-        iommu_table_u3.it_busno = 0;
-        iommu_table_u3.it_offset = 0;
+        iommu_table_dart.it_busno = 0;
+        iommu_table_dart.it_offset = 0;
         /* it_size is in number of entries */
-        iommu_table_u3.it_size = (dart_tablesize / sizeof(u32)) >> DART_PAGE_FACTOR;
+        iommu_table_dart.it_size = (dart_tablesize / sizeof(u32)) >> DART_PAGE_FACTOR;
 
         /* Initialize the common IOMMU code */
-        iommu_table_u3.it_base = (unsigned long)dart_vbase;
-        iommu_table_u3.it_index = 0;
-        iommu_table_u3.it_blocksize = 1;
-        iommu_init_table(&iommu_table_u3);
+        iommu_table_dart.it_base = (unsigned long)dart_vbase;
+        iommu_table_dart.it_index = 0;
+        iommu_table_dart.it_blocksize = 1;
+        iommu_init_table(&iommu_table_dart);
 
         /* Reserve the last page of the DART to avoid possible prefetch
          * past the DART mapped area
          */
-        set_bit(iommu_table_u3.it_size - 1, iommu_table_u3.it_map);
+        set_bit(iommu_table_dart.it_size - 1, iommu_table_dart.it_map);
 }
 
-static void iommu_dev_setup_u3(struct pci_dev *dev)
+static void iommu_dev_setup_dart(struct pci_dev *dev)
 {
         struct device_node *dn;
 
@@ -254,35 +270,39 @@ static void iommu_dev_setup_u3(struct pci_dev *dev)
         dn = pci_device_to_OF_node(dev);
 
         if (dn)
-                PCI_DN(dn)->iommu_table = &iommu_table_u3;
+                PCI_DN(dn)->iommu_table = &iommu_table_dart;
 }
 
-static void iommu_bus_setup_u3(struct pci_bus *bus)
+static void iommu_bus_setup_dart(struct pci_bus *bus)
 {
         struct device_node *dn;
 
-        if (!iommu_table_u3_inited) {
-                iommu_table_u3_inited = 1;
-                iommu_table_u3_setup();
+        if (!iommu_table_dart_inited) {
+                iommu_table_dart_inited = 1;
+                iommu_table_dart_setup();
         }
 
         dn = pci_bus_to_OF_node(bus);
 
         if (dn)
-                PCI_DN(dn)->iommu_table = &iommu_table_u3;
+                PCI_DN(dn)->iommu_table = &iommu_table_dart;
 }
 
 static void iommu_dev_setup_null(struct pci_dev *dev) { }
 static void iommu_bus_setup_null(struct pci_bus *bus) { }
 
-void iommu_init_early_u3(void)
+void iommu_init_early_dart(void)
 {
         struct device_node *dn;
 
         /* Find the DART in the device-tree */
         dn = of_find_compatible_node(NULL, "dart", "u3-dart");
-        if (dn == NULL)
-                return;
+        if (dn == NULL) {
+                dn = of_find_compatible_node(NULL, "dart", "u4-dart");
+                if (dn == NULL)
+                        goto bail;
+                dart_is_u4 = 1;
+        }
 
         /* Setup low level TCE operations for the core IOMMU code */
         ppc_md.tce_build = dart_build;
@@ -290,24 +310,27 @@ void iommu_init_early_u3(void)
         ppc_md.tce_flush = dart_flush;
 
         /* Initialize the DART HW */
-        if (dart_init(dn)) {
-                /* If init failed, use direct iommu and null setup functions */
-                ppc_md.iommu_dev_setup = iommu_dev_setup_null;
-                ppc_md.iommu_bus_setup = iommu_bus_setup_null;
-
-                /* Setup pci_dma ops */
-                pci_direct_iommu_init();
-        } else {
-                ppc_md.iommu_dev_setup = iommu_dev_setup_u3;
-                ppc_md.iommu_bus_setup = iommu_bus_setup_u3;
+        if (dart_init(dn) == 0) {
+                ppc_md.iommu_dev_setup = iommu_dev_setup_dart;
+                ppc_md.iommu_bus_setup = iommu_bus_setup_dart;
 
                 /* Setup pci_dma ops */
                 pci_iommu_init();
+
+                return;
         }
+
+ bail:
+        /* If init failed, use direct iommu and null setup functions */
+        ppc_md.iommu_dev_setup = iommu_dev_setup_null;
+        ppc_md.iommu_bus_setup = iommu_bus_setup_null;
+
+        /* Setup pci_dma ops */
+        pci_direct_iommu_init();
 }
 
 
-void __init alloc_u3_dart_table(void)
+void __init alloc_dart_table(void)
 {
         /* Only reserve DART space if machine has more than 2GB of RAM
          * or if requested with iommu=on on cmdline.
@@ -323,5 +346,5 @@ void __init alloc_u3_dart_table(void)
         dart_tablebase = (unsigned long)
                 abs_to_virt(lmb_alloc_base(1UL<<24, 1UL<<24, 0x80000000L));
 
-        printk(KERN_INFO "U3-DART allocated at: %lx\n", dart_tablebase);
+        printk(KERN_INFO "DART table allocated at: %lx\n", dart_tablebase);
 }
diff --git a/arch/powerpc/sysdev/mpic.c b/arch/powerpc/sysdev/mpic.c
index 9513ea78e6c1..4f26304d0263 100644
--- a/arch/powerpc/sysdev/mpic.c
+++ b/arch/powerpc/sysdev/mpic.c
@@ -13,6 +13,9 @@
  */
 
 #undef DEBUG
+#undef DEBUG_IPI
+#undef DEBUG_IRQ
+#undef DEBUG_LOW
 
 #include <linux/config.h>
 #include <linux/types.h>
@@ -168,35 +171,86 @@ static void __init mpic_test_broken_ipi(struct mpic *mpic)
 /* 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)
+static inline int mpic_is_ht_interrupt(struct mpic *mpic, unsigned int source)
 {
-        if (source_no >= 128 || !mpic->fixups)
+        if (source >= 128 || !mpic->fixups)
                 return 0;
-        return mpic->fixups[source_no].base != NULL;
+        return mpic->fixups[source].base != NULL;
 }
 
 
-static inline void mpic_apic_end_irq(struct mpic *mpic, unsigned int source_no)
+static inline void mpic_ht_end_irq(struct mpic *mpic, unsigned int source)
 {
-        struct mpic_irq_fixup *fixup = &mpic->fixups[source_no];
+        struct mpic_irq_fixup *fixup = &mpic->fixups[source];
 
-        spin_lock(&mpic->fixup_lock);
-        writeb(0x11 + 2 * fixup->irq, fixup->base + 2);
-        writel(fixup->data, fixup->base + 4);
-        spin_unlock(&mpic->fixup_lock);
+        if (fixup->applebase) {
+                unsigned int soff = (fixup->index >> 3) & ~3;
+                unsigned int mask = 1U << (fixup->index & 0x1f);
+                writel(mask, fixup->applebase + soff);
+        } else {
+                spin_lock(&mpic->fixup_lock);
+                writeb(0x11 + 2 * fixup->index, fixup->base + 2);
+                writel(fixup->data, fixup->base + 4);
+                spin_unlock(&mpic->fixup_lock);
+        }
 }
 
+static void mpic_startup_ht_interrupt(struct mpic *mpic, unsigned int source,
+                                      unsigned int irqflags)
+{
+        struct mpic_irq_fixup *fixup = &mpic->fixups[source];
+        unsigned long flags;
+        u32 tmp;
+
+        if (fixup->base == NULL)
+                return;
+
+        DBG("startup_ht_interrupt(%u, %u) index: %d\n",
+            source, irqflags, fixup->index);
+        spin_lock_irqsave(&mpic->fixup_lock, flags);
+        /* Enable and configure */
+        writeb(0x10 + 2 * fixup->index, fixup->base + 2);
+        tmp = readl(fixup->base + 4);
+        tmp &= ~(0x23U);
+        if (irqflags & IRQ_LEVEL)
+                tmp |= 0x22;
+        writel(tmp, fixup->base + 4);
+        spin_unlock_irqrestore(&mpic->fixup_lock, flags);
+}
+
+static void mpic_shutdown_ht_interrupt(struct mpic *mpic, unsigned int source,
+                                       unsigned int irqflags)
+{
+        struct mpic_irq_fixup *fixup = &mpic->fixups[source];
+        unsigned long flags;
+        u32 tmp;
+
+        if (fixup->base == NULL)
+                return;
+
+        DBG("shutdown_ht_interrupt(%u, %u)\n", source, irqflags);
+
+        /* Disable */
+        spin_lock_irqsave(&mpic->fixup_lock, flags);
+        writeb(0x10 + 2 * fixup->index, fixup->base + 2);
+        tmp = readl(fixup->base + 4);
+        tmp &= ~1U;
+        writel(tmp, fixup->base + 4);
+        spin_unlock_irqrestore(&mpic->fixup_lock, flags);
+}
 
-static void __init mpic_scan_ioapic(struct mpic *mpic, u8 __iomem *devbase)
+static void __init mpic_scan_ht_pic(struct mpic *mpic, u8 __iomem *devbase,
+                                    unsigned int devfn, u32 vdid)
 {
         int i, irq, n;
+        u8 __iomem *base;
         u32 tmp;
         u8 pos;
 
-        for (pos = readb(devbase + 0x34); pos; pos = readb(devbase + pos + 1)) {
-                u8 id = readb(devbase + pos);
-
-                if (id == 0x08) {
+        for (pos = readb(devbase + PCI_CAPABILITY_LIST); pos != 0;
+             pos = readb(devbase + pos + PCI_CAP_LIST_NEXT)) {
+                u8 id = readb(devbase + pos + PCI_CAP_LIST_ID);
+                if (id == PCI_CAP_ID_HT_IRQCONF) {
                         id = readb(devbase + pos + 3);
                         if (id == 0x80)
                                 break;
@@ -205,33 +259,41 @@ static void __init mpic_scan_ioapic(struct mpic *mpic, u8 __iomem *devbase)
         if (pos == 0)
                 return;
 
-        printk(KERN_INFO "mpic:    - Workarounds @ %p, pos = 0x%02x\n", devbase, pos);
+        base = devbase + pos;
+        writeb(0x01, base + 2);
+        n = (readl(base + 4) >> 16) & 0xff;
 
-        devbase += pos;
-
-        writeb(0x01, devbase + 2);
-        n = (readl(devbase + 4) >> 16) & 0xff;
+        printk(KERN_INFO "mpic:   - HT:%02x.%x [0x%02x] vendor %04x device %04x"
+               " has %d irqs\n",
+               devfn >> 3, devfn & 0x7, pos, vdid & 0xffff, vdid >> 16, n + 1);
 
         for (i = 0; i <= n; i++) {
-                writeb(0x10 + 2 * i, devbase + 2);
-                tmp = readl(devbase + 4);
-                if ((tmp & 0x21) != 0x20)
-                        continue;
+                writeb(0x10 + 2 * i, base + 2);
+                tmp = readl(base + 4);
                 irq = (tmp >> 16) & 0xff;
-                mpic->fixups[irq].irq = i;
-                mpic->fixups[irq].base = devbase;
-                writeb(0x11 + 2 * i, devbase + 2);
-                mpic->fixups[irq].data = readl(devbase + 4) | 0x80000000;
+                DBG("HT PIC index 0x%x, irq 0x%x, tmp: %08x\n", i, irq, tmp);
+                /* mask it , will be unmasked later */
+                tmp |= 0x1;
+                writel(tmp, base + 4);
+                mpic->fixups[irq].index = i;
+                mpic->fixups[irq].base = base;
+                /* Apple HT PIC has a non-standard way of doing EOIs */
+                if ((vdid & 0xffff) == 0x106b)
+                        mpic->fixups[irq].applebase = devbase + 0x60;
+                else
+                        mpic->fixups[irq].applebase = NULL;
+                writeb(0x11 + 2 * i, base + 2);
+                mpic->fixups[irq].data = readl(base + 4) | 0x80000000;
         }
 }
  
 
-static void __init mpic_scan_ioapics(struct mpic *mpic)
+static void __init mpic_scan_ht_pics(struct mpic *mpic)
 {
         unsigned int devfn;
         u8 __iomem *cfgspace;
 
-        printk(KERN_INFO "mpic: Setting up IO-APICs workarounds for U3\n");
+        printk(KERN_INFO "mpic: Setting up HT PICs workarounds for U3/U4\n");
 
         /* Allocate fixups array */
         mpic->fixups = alloc_bootmem(128 * sizeof(struct mpic_irq_fixup));
@@ -247,13 +309,14 @@ static void __init mpic_scan_ioapics(struct mpic *mpic)
         cfgspace = ioremap(0xf2000000, 0x10000);
         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
+        /* 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 < 0x100; devfn++) {
                 u8 __iomem *devbase = cfgspace + (devfn << 8);
                 u8 hdr_type = readb(devbase + PCI_HEADER_TYPE);
                 u32 l = readl(devbase + PCI_VENDOR_ID);
+                u16 s;
 
                 DBG("devfn %x, l: %x\n", devfn, l);
 
@@ -261,8 +324,12 @@ static void __init mpic_scan_ioapics(struct mpic *mpic)
                 if (l == 0xffffffff || l == 0x00000000 ||
                     l == 0x0000ffff || l == 0xffff0000)
                         goto next;
+                /* Check if is supports capability lists */
+                s = readw(devbase + PCI_STATUS);
+                if (!(s & PCI_STATUS_CAP_LIST))
+                        goto next;
 
-                mpic_scan_ioapic(mpic, devbase);
+                mpic_scan_ht_pic(mpic, devbase, devfn, l);
 
         next:
                 /* next device, if function 0 */
@@ -363,6 +430,31 @@ static void mpic_enable_irq(unsigned int irq)
                         break;
                 }
         } while(mpic_irq_read(src, MPIC_IRQ_VECTOR_PRI) & MPIC_VECPRI_MASK);    
+
+#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) &&
+                    (irq_desc[irq].status & IRQ_LEVEL))
+                        mpic_ht_end_irq(mpic, src);
+        }
+#endif /* CONFIG_MPIC_BROKEN_U3 */
+}
+
+static unsigned int mpic_startup_irq(unsigned int irq)
+{
+#ifdef CONFIG_MPIC_BROKEN_U3
+        struct mpic *mpic = mpic_from_irq(irq);
+        unsigned int src = irq - mpic->irq_offset;
+
+        if (mpic_is_ht_interrupt(mpic, src))
+                mpic_startup_ht_interrupt(mpic, src, irq_desc[irq].status);
+
+#endif /* CONFIG_MPIC_BROKEN_U3 */
+
+        mpic_enable_irq(irq);
+
+        return 0;
 }
 
 static void mpic_disable_irq(unsigned int irq)
@@ -386,12 +478,27 @@ static void mpic_disable_irq(unsigned int irq)
         } while(!(mpic_irq_read(src, MPIC_IRQ_VECTOR_PRI) & MPIC_VECPRI_MASK));
 }
 
+static void mpic_shutdown_irq(unsigned int irq)
+{
+#ifdef CONFIG_MPIC_BROKEN_U3
+        struct mpic *mpic = mpic_from_irq(irq);
+        unsigned int src = irq - mpic->irq_offset;
+
+        if (mpic_is_ht_interrupt(mpic, src))
+                mpic_shutdown_ht_interrupt(mpic, src, irq_desc[irq].status);
+
+#endif /* CONFIG_MPIC_BROKEN_U3 */
+
+        mpic_disable_irq(irq);
+}
+
 static void mpic_end_irq(unsigned int irq)
 {
         struct mpic *mpic = mpic_from_irq(irq);
 
+#ifdef DEBUG_IRQ
         DBG("%s: end_irq: %d\n", mpic->name, irq);
-
+#endif
         /* 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
@@ -400,8 +507,9 @@ static void mpic_end_irq(unsigned int irq)
 #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);
+                if (mpic_is_ht_interrupt(mpic, src) &&
+                    (irq_desc[irq].status & IRQ_LEVEL))
+                        mpic_ht_end_irq(mpic, src);
         }
 #endif /* CONFIG_MPIC_BROKEN_U3 */
 
@@ -482,6 +590,8 @@ struct mpic * __init mpic_alloc(unsigned long phys_addr,
         mpic->name = name;
 
         mpic->hc_irq.typename = name;
+        mpic->hc_irq.startup = mpic_startup_irq;
+        mpic->hc_irq.shutdown = mpic_shutdown_irq;
         mpic->hc_irq.enable = mpic_enable_irq;
         mpic->hc_irq.disable = mpic_disable_irq;
         mpic->hc_irq.end = mpic_end_irq;
@@ -650,10 +760,10 @@ void __init mpic_init(struct mpic *mpic)
                 mpic->irq_count = mpic->num_sources;
 
 #ifdef CONFIG_MPIC_BROKEN_U3
-        /* Do the ioapic fixups on U3 broken mpic */
+        /* Do the HT PIC 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);
+                mpic_scan_ht_pics(mpic);
 #endif /* CONFIG_MPIC_BROKEN_U3 */
 
         for (i = 0; i < mpic->num_sources; i++) {
@@ -840,7 +950,9 @@ void mpic_send_ipi(unsigned int ipi_no, unsigned int cpu_mask)
 
         BUG_ON(mpic == NULL);
 
+#ifdef DEBUG_IPI
         DBG("%s: send_ipi(ipi_no: %d)\n", mpic->name, ipi_no);
+#endif
 
         mpic_cpu_write(MPIC_CPU_IPI_DISPATCH_0 + ipi_no * 0x10,
                        mpic_physmask(cpu_mask & cpus_addr(cpu_online_map)[0]));
@@ -851,19 +963,28 @@ 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;
+#ifdef DEBUG_LOW
         DBG("%s: get_one_irq(): %d\n", mpic->name, irq);
-
+#endif
         if (mpic->cascade && irq == mpic->cascade_vec) {
+#ifdef DEBUG_LOW
                 DBG("%s: cascading ...\n", mpic->name);
+#endif
                 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) 
+        if (irq < MPIC_VEC_IPI_0) {
+#ifdef DEBUG_IRQ
+                DBG("%s: irq %d\n", mpic->name, irq + mpic->irq_offset);
+#endif
                 return irq + mpic->irq_offset;
+        }
+#ifdef DEBUG_IPI
         DBG("%s: ipi %d !\n", mpic->name, irq - MPIC_VEC_IPI_0);
+#endif
         return irq - MPIC_VEC_IPI_0 + mpic->ipi_offset;
 }