1 files changed, 1018 insertions, 0 deletions

diff --git a/arch/x86_64/kernel/pci-calgary.c b/arch/x86_64/kernel/pci-calgary.c
new file mode 100644
index 000000000000..d91cb843f54d
--- /dev/null
+++ b/arch/x86_64/kernel/pci-calgary.c
@@ -0,0 +1,1018 @@
+/*
+ * Derived from arch/powerpc/kernel/iommu.c
+ *
+ * Copyright (C) 2006 Jon Mason <jdmason@us.ibm.com>, IBM Corporation
+ * Copyright (C) 2006 Muli Ben-Yehuda <muli@il.ibm.com>, IBM Corporation
+ *
+ * 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
+ */
+
+#include <linux/config.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/mm.h>
+#include <linux/spinlock.h>
+#include <linux/string.h>
+#include <linux/dma-mapping.h>
+#include <linux/init.h>
+#include <linux/bitops.h>
+#include <linux/pci_ids.h>
+#include <linux/pci.h>
+#include <linux/delay.h>
+#include <asm/proto.h>
+#include <asm/calgary.h>
+#include <asm/tce.h>
+#include <asm/pci-direct.h>
+#include <asm/system.h>
+#include <asm/dma.h>
+
+#define PCI_DEVICE_ID_IBM_CALGARY 0x02a1
+#define PCI_VENDOR_DEVICE_ID_CALGARY \
+        (PCI_VENDOR_ID_IBM | PCI_DEVICE_ID_IBM_CALGARY << 16)
+
+/* we need these for register space address calculation */
+#define START_ADDRESS           0xfe000000
+#define CHASSIS_BASE            0
+#define ONE_BASED_CHASSIS_NUM   1
+
+/* register offsets inside the host bridge space */
+#define PHB_CSR_OFFSET          0x0110
+#define PHB_PLSSR_OFFSET        0x0120
+#define PHB_CONFIG_RW_OFFSET    0x0160
+#define PHB_IOBASE_BAR_LOW      0x0170
+#define PHB_IOBASE_BAR_HIGH     0x0180
+#define PHB_MEM_1_LOW           0x0190
+#define PHB_MEM_1_HIGH          0x01A0
+#define PHB_IO_ADDR_SIZE        0x01B0
+#define PHB_MEM_1_SIZE          0x01C0
+#define PHB_MEM_ST_OFFSET       0x01D0
+#define PHB_AER_OFFSET          0x0200
+#define PHB_CONFIG_0_HIGH       0x0220
+#define PHB_CONFIG_0_LOW        0x0230
+#define PHB_CONFIG_0_END        0x0240
+#define PHB_MEM_2_LOW           0x02B0
+#define PHB_MEM_2_HIGH          0x02C0
+#define PHB_MEM_2_SIZE_HIGH     0x02D0
+#define PHB_MEM_2_SIZE_LOW      0x02E0
+#define PHB_DOSHOLE_OFFSET      0x08E0
+
+/* PHB_CONFIG_RW */
+#define PHB_TCE_ENABLE          0x20000000
+#define PHB_SLOT_DISABLE        0x1C000000
+#define PHB_DAC_DISABLE         0x01000000
+#define PHB_MEM2_ENABLE         0x00400000
+#define PHB_MCSR_ENABLE         0x00100000
+/* TAR (Table Address Register) */
+#define TAR_SW_BITS             0x0000ffffffff800fUL
+#define TAR_VALID               0x0000000000000008UL
+/* CSR (Channel/DMA Status Register) */
+#define CSR_AGENT_MASK          0xffe0ffff
+
+#define MAX_NUM_OF_PHBS         8 /* how many PHBs in total? */
+#define MAX_PHB_BUS_NUM         (MAX_NUM_OF_PHBS * 2) /* max dev->bus->number */
+#define PHBS_PER_CALGARY        4
+
+/* register offsets in Calgary's internal register space */
+static const unsigned long tar_offsets[] = {
+        0x0580 /* TAR0 */,
+        0x0588 /* TAR1 */,
+        0x0590 /* TAR2 */,
+        0x0598 /* TAR3 */
+};
+
+static const unsigned long split_queue_offsets[] = {
+        0x4870 /* SPLIT QUEUE 0 */,
+        0x5870 /* SPLIT QUEUE 1 */,
+        0x6870 /* SPLIT QUEUE 2 */,
+        0x7870 /* SPLIT QUEUE 3 */
+};
+
+static const unsigned long phb_offsets[] = {
+        0x8000 /* PHB0 */,
+        0x9000 /* PHB1 */,
+        0xA000 /* PHB2 */,
+        0xB000 /* PHB3 */
+};
+
+void* tce_table_kva[MAX_NUM_OF_PHBS * MAX_NUMNODES];
+unsigned int specified_table_size = TCE_TABLE_SIZE_UNSPECIFIED;
+static int translate_empty_slots __read_mostly = 0;
+static int calgary_detected __read_mostly = 0;
+
+/*
+ * the bitmap of PHBs the user requested that we disable
+ * translation on.
+ */
+static DECLARE_BITMAP(translation_disabled, MAX_NUMNODES * MAX_PHB_BUS_NUM);
+
+static void tce_cache_blast(struct iommu_table *tbl);
+
+/* enable this to stress test the chip's TCE cache */
+#ifdef CONFIG_IOMMU_DEBUG
+static inline void tce_cache_blast_stress(struct iommu_table *tbl)
+{
+        tce_cache_blast(tbl);
+}
+#else
+static inline void tce_cache_blast_stress(struct iommu_table *tbl)
+{
+}
+#endif /* BLAST_TCE_CACHE_ON_UNMAP */
+
+static inline unsigned int num_dma_pages(unsigned long dma, unsigned int dmalen)
+{
+        unsigned int npages;
+
+        npages = PAGE_ALIGN(dma + dmalen) - (dma & PAGE_MASK);
+        npages >>= PAGE_SHIFT;
+
+        return npages;
+}
+
+static inline int translate_phb(struct pci_dev* dev)
+{
+        int disabled = test_bit(dev->bus->number, translation_disabled);
+        return !disabled;
+}
+
+static void iommu_range_reserve(struct iommu_table *tbl,
+        unsigned long start_addr, unsigned int npages)
+{
+        unsigned long index;
+        unsigned long end;
+
+        index = start_addr >> PAGE_SHIFT;
+
+        /* bail out if we're asked to reserve a region we don't cover */
+        if (index >= tbl->it_size)
+                return;
+
+        end = index + npages;
+        if (end > tbl->it_size) /* don't go off the table */
+                end = tbl->it_size;
+
+        while (index < end) {
+                if (test_bit(index, tbl->it_map))
+                        printk(KERN_ERR "Calgary: entry already allocated at "
+                               "0x%lx tbl %p dma 0x%lx npages %u\n",
+                               index, tbl, start_addr, npages);
+                ++index;
+        }
+        set_bit_string(tbl->it_map, start_addr >> PAGE_SHIFT, npages);
+}
+
+static unsigned long iommu_range_alloc(struct iommu_table *tbl,
+        unsigned int npages)
+{
+        unsigned long offset;
+
+        BUG_ON(npages == 0);
+
+        offset = find_next_zero_string(tbl->it_map, tbl->it_hint,
+                                       tbl->it_size, npages);
+        if (offset == ~0UL) {
+                tce_cache_blast(tbl);
+                offset = find_next_zero_string(tbl->it_map, 0,
+                                               tbl->it_size, npages);
+                if (offset == ~0UL) {
+                        printk(KERN_WARNING "Calgary: IOMMU full.\n");
+                        if (panic_on_overflow)
+                                panic("Calgary: fix the allocator.\n");
+                        else
+                                return bad_dma_address;
+                }
+        }
+
+        set_bit_string(tbl->it_map, offset, npages);
+        tbl->it_hint = offset + npages;
+        BUG_ON(tbl->it_hint > tbl->it_size);
+
+        return offset;
+}
+
+static dma_addr_t iommu_alloc(struct iommu_table *tbl, void *vaddr,
+        unsigned int npages, int direction)
+{
+        unsigned long entry, flags;
+        dma_addr_t ret = bad_dma_address;
+
+        spin_lock_irqsave(&tbl->it_lock, flags);
+
+        entry = iommu_range_alloc(tbl, npages);
+
+        if (unlikely(entry == bad_dma_address))
+                goto error;
+
+        /* set the return dma address */
+        ret = (entry << PAGE_SHIFT) | ((unsigned long)vaddr & ~PAGE_MASK);
+
+        /* put the TCEs in the HW table */
+        tce_build(tbl, entry, npages, (unsigned long)vaddr & PAGE_MASK,
+                  direction);
+
+        spin_unlock_irqrestore(&tbl->it_lock, flags);
+
+        return ret;
+
+error:
+        spin_unlock_irqrestore(&tbl->it_lock, flags);
+        printk(KERN_WARNING "Calgary: failed to allocate %u pages in "
+               "iommu %p\n", npages, tbl);
+        return bad_dma_address;
+}
+
+static void __iommu_free(struct iommu_table *tbl, dma_addr_t dma_addr,
+        unsigned int npages)
+{
+        unsigned long entry;
+        unsigned long i;
+
+        entry = dma_addr >> PAGE_SHIFT;
+
+        BUG_ON(entry + npages > tbl->it_size);
+
+        tce_free(tbl, entry, npages);
+
+        for (i = 0; i < npages; ++i) {
+                if (!test_bit(entry + i, tbl->it_map))
+                        printk(KERN_ERR "Calgary: bit is off at 0x%lx "
+                               "tbl %p dma 0x%Lx entry 0x%lx npages %u\n",
+                               entry + i, tbl, dma_addr, entry, npages);
+        }
+
+        __clear_bit_string(tbl->it_map, entry, npages);
+
+        tce_cache_blast_stress(tbl);
+}
+
+static void iommu_free(struct iommu_table *tbl, dma_addr_t dma_addr,
+        unsigned int npages)
+{
+        unsigned long flags;
+
+        spin_lock_irqsave(&tbl->it_lock, flags);
+
+        __iommu_free(tbl, dma_addr, npages);
+
+        spin_unlock_irqrestore(&tbl->it_lock, flags);
+}
+
+static void __calgary_unmap_sg(struct iommu_table *tbl,
+        struct scatterlist *sglist, int nelems, int direction)
+{
+        while (nelems--) {
+                unsigned int npages;
+                dma_addr_t dma = sglist->dma_address;
+                unsigned int dmalen = sglist->dma_length;
+
+                if (dmalen == 0)
+                        break;
+
+                npages = num_dma_pages(dma, dmalen);
+                __iommu_free(tbl, dma, npages);
+                sglist++;
+        }
+}
+
+void calgary_unmap_sg(struct device *dev, struct scatterlist *sglist,
+                      int nelems, int direction)
+{
+        unsigned long flags;
+        struct iommu_table *tbl = to_pci_dev(dev)->bus->self->sysdata;
+
+        if (!translate_phb(to_pci_dev(dev)))
+                return;
+
+        spin_lock_irqsave(&tbl->it_lock, flags);
+
+        __calgary_unmap_sg(tbl, sglist, nelems, direction);
+
+        spin_unlock_irqrestore(&tbl->it_lock, flags);
+}
+
+static int calgary_nontranslate_map_sg(struct device* dev,
+        struct scatterlist *sg, int nelems, int direction)
+{
+        int i;
+
+        for (i = 0; i < nelems; i++ ) {
+                struct scatterlist *s = &sg[i];
+                BUG_ON(!s->page);
+                s->dma_address = virt_to_bus(page_address(s->page) +s->offset);
+                s->dma_length = s->length;
+        }
+        return nelems;
+}
+
+int calgary_map_sg(struct device *dev, struct scatterlist *sg,
+        int nelems, int direction)
+{
+        struct iommu_table *tbl = to_pci_dev(dev)->bus->self->sysdata;
+        unsigned long flags;
+        unsigned long vaddr;
+        unsigned int npages;
+        unsigned long entry;
+        int i;
+
+        if (!translate_phb(to_pci_dev(dev)))
+                return calgary_nontranslate_map_sg(dev, sg, nelems, direction);
+
+        spin_lock_irqsave(&tbl->it_lock, flags);
+
+        for (i = 0; i < nelems; i++ ) {
+                struct scatterlist *s = &sg[i];
+                BUG_ON(!s->page);
+
+                vaddr = (unsigned long)page_address(s->page) + s->offset;
+                npages = num_dma_pages(vaddr, s->length);
+
+                entry = iommu_range_alloc(tbl, npages);
+                if (entry == bad_dma_address) {
+                        /* makes sure unmap knows to stop */
+                        s->dma_length = 0;
+                        goto error;
+                }
+
+                s->dma_address = (entry << PAGE_SHIFT) | s->offset;
+
+                /* insert into HW table */
+                tce_build(tbl, entry, npages, vaddr & PAGE_MASK,
+                          direction);
+
+                s->dma_length = s->length;
+        }
+
+        spin_unlock_irqrestore(&tbl->it_lock, flags);
+
+        return nelems;
+error:
+        __calgary_unmap_sg(tbl, sg, nelems, direction);
+        for (i = 0; i < nelems; i++) {
+                sg[i].dma_address = bad_dma_address;
+                sg[i].dma_length = 0;
+        }
+        spin_unlock_irqrestore(&tbl->it_lock, flags);
+        return 0;
+}
+
+dma_addr_t calgary_map_single(struct device *dev, void *vaddr,
+        size_t size, int direction)
+{
+        dma_addr_t dma_handle = bad_dma_address;
+        unsigned long uaddr;
+        unsigned int npages;
+        struct iommu_table *tbl = to_pci_dev(dev)->bus->self->sysdata;
+
+        uaddr = (unsigned long)vaddr;
+        npages = num_dma_pages(uaddr, size);
+
+        if (translate_phb(to_pci_dev(dev)))
+                dma_handle = iommu_alloc(tbl, vaddr, npages, direction);
+        else
+                dma_handle = virt_to_bus(vaddr);
+
+        return dma_handle;
+}
+
+void calgary_unmap_single(struct device *dev, dma_addr_t dma_handle,
+        size_t size, int direction)
+{
+        struct iommu_table *tbl = to_pci_dev(dev)->bus->self->sysdata;
+        unsigned int npages;
+
+        if (!translate_phb(to_pci_dev(dev)))
+                return;
+
+        npages = num_dma_pages(dma_handle, size);
+        iommu_free(tbl, dma_handle, npages);
+}
+
+void* calgary_alloc_coherent(struct device *dev, size_t size,
+        dma_addr_t *dma_handle, gfp_t flag)
+{
+        void *ret = NULL;
+        dma_addr_t mapping;
+        unsigned int npages, order;
+        struct iommu_table *tbl;
+
+        tbl = to_pci_dev(dev)->bus->self->sysdata;
+
+        size = PAGE_ALIGN(size); /* size rounded up to full pages */
+        npages = size >> PAGE_SHIFT;
+        order = get_order(size);
+
+        /* alloc enough pages (and possibly more) */
+        ret = (void *)__get_free_pages(flag, order);
+        if (!ret)
+                goto error;
+        memset(ret, 0, size);
+
+        if (translate_phb(to_pci_dev(dev))) {
+                /* set up tces to cover the allocated range */
+                mapping = iommu_alloc(tbl, ret, npages, DMA_BIDIRECTIONAL);
+                if (mapping == bad_dma_address)
+                        goto free;
+
+                *dma_handle = mapping;
+        } else /* non translated slot */
+                *dma_handle = virt_to_bus(ret);
+
+        return ret;
+
+free:
+        free_pages((unsigned long)ret, get_order(size));
+        ret = NULL;
+error:
+        return ret;
+}
+
+static struct dma_mapping_ops calgary_dma_ops = {
+        .alloc_coherent = calgary_alloc_coherent,
+        .map_single = calgary_map_single,
+        .unmap_single = calgary_unmap_single,
+        .map_sg = calgary_map_sg,
+        .unmap_sg = calgary_unmap_sg,
+};
+
+static inline int busno_to_phbid(unsigned char num)
+{
+        return bus_to_phb(num) % PHBS_PER_CALGARY;
+}
+
+static inline unsigned long split_queue_offset(unsigned char num)
+{
+        size_t idx = busno_to_phbid(num);
+
+        return split_queue_offsets[idx];
+}
+
+static inline unsigned long tar_offset(unsigned char num)
+{
+        size_t idx = busno_to_phbid(num);
+
+        return tar_offsets[idx];
+}
+
+static inline unsigned long phb_offset(unsigned char num)
+{
+        size_t idx = busno_to_phbid(num);
+
+        return phb_offsets[idx];
+}
+
+static inline void __iomem* calgary_reg(void __iomem *bar, unsigned long offset)
+{
+        unsigned long target = ((unsigned long)bar) | offset;
+        return (void __iomem*)target;
+}
+
+static void tce_cache_blast(struct iommu_table *tbl)
+{
+        u64 val;
+        u32 aer;
+        int i = 0;
+        void __iomem *bbar = tbl->bbar;
+        void __iomem *target;
+
+        /* disable arbitration on the bus */
+        target = calgary_reg(bbar, phb_offset(tbl->it_busno) | PHB_AER_OFFSET);
+        aer = readl(target);
+        writel(0, target);
+
+        /* read plssr to ensure it got there */
+        target = calgary_reg(bbar, phb_offset(tbl->it_busno) | PHB_PLSSR_OFFSET);
+        val = readl(target);
+
+        /* poll split queues until all DMA activity is done */
+        target = calgary_reg(bbar, split_queue_offset(tbl->it_busno));
+        do {
+                val = readq(target);
+                i++;
+        } while ((val & 0xff) != 0xff && i < 100);
+        if (i == 100)
+                printk(KERN_WARNING "Calgary: PCI bus not quiesced, "
+                       "continuing anyway\n");
+
+        /* invalidate TCE cache */
+        target = calgary_reg(bbar, tar_offset(tbl->it_busno));
+        writeq(tbl->tar_val, target);
+
+        /* enable arbitration */
+        target = calgary_reg(bbar, phb_offset(tbl->it_busno) | PHB_AER_OFFSET);
+        writel(aer, target);
+        (void)readl(target); /* flush */
+}
+
+static void __init calgary_reserve_mem_region(struct pci_dev *dev, u64 start,
+        u64 limit)
+{
+        unsigned int numpages;
+
+        limit = limit | 0xfffff;
+        limit++;
+
+        numpages = ((limit - start) >> PAGE_SHIFT);
+        iommu_range_reserve(dev->sysdata, start, numpages);
+}
+
+static void __init calgary_reserve_peripheral_mem_1(struct pci_dev *dev)
+{
+        void __iomem *target;
+        u64 low, high, sizelow;
+        u64 start, limit;
+        struct iommu_table *tbl = dev->sysdata;
+        unsigned char busnum = dev->bus->number;
+        void __iomem *bbar = tbl->bbar;
+
+        /* peripheral MEM_1 region */
+        target = calgary_reg(bbar, phb_offset(busnum) | PHB_MEM_1_LOW);
+        low = be32_to_cpu(readl(target));
+        target = calgary_reg(bbar, phb_offset(busnum) | PHB_MEM_1_HIGH);
+        high = be32_to_cpu(readl(target));
+        target = calgary_reg(bbar, phb_offset(busnum) | PHB_MEM_1_SIZE);
+        sizelow = be32_to_cpu(readl(target));
+
+        start = (high << 32) | low;
+        limit = sizelow;
+
+        calgary_reserve_mem_region(dev, start, limit);
+}
+
+static void __init calgary_reserve_peripheral_mem_2(struct pci_dev *dev)
+{
+        void __iomem *target;
+        u32 val32;
+        u64 low, high, sizelow, sizehigh;
+        u64 start, limit;
+        struct iommu_table *tbl = dev->sysdata;
+        unsigned char busnum = dev->bus->number;
+        void __iomem *bbar = tbl->bbar;
+
+        /* is it enabled? */
+        target = calgary_reg(bbar, phb_offset(busnum) | PHB_CONFIG_RW_OFFSET);
+        val32 = be32_to_cpu(readl(target));
+        if (!(val32 & PHB_MEM2_ENABLE))
+                return;
+
+        target = calgary_reg(bbar, phb_offset(busnum) | PHB_MEM_2_LOW);
+        low = be32_to_cpu(readl(target));
+        target = calgary_reg(bbar, phb_offset(busnum) | PHB_MEM_2_HIGH);
+        high = be32_to_cpu(readl(target));
+        target = calgary_reg(bbar, phb_offset(busnum) | PHB_MEM_2_SIZE_LOW);
+        sizelow = be32_to_cpu(readl(target));
+        target = calgary_reg(bbar, phb_offset(busnum) | PHB_MEM_2_SIZE_HIGH);
+        sizehigh = be32_to_cpu(readl(target));
+
+        start = (high << 32) | low;
+        limit = (sizehigh << 32) | sizelow;
+
+        calgary_reserve_mem_region(dev, start, limit);
+}
+
+/*
+ * some regions of the IO address space do not get translated, so we
+ * must not give devices IO addresses in those regions. The regions
+ * are the 640KB-1MB region and the two PCI peripheral memory holes.
+ * Reserve all of them in the IOMMU bitmap to avoid giving them out
+ * later.
+ */
+static void __init calgary_reserve_regions(struct pci_dev *dev)
+{
+        unsigned int npages;
+        void __iomem *bbar;
+        unsigned char busnum;
+        u64 start;
+        struct iommu_table *tbl = dev->sysdata;
+
+        bbar = tbl->bbar;
+        busnum = dev->bus->number;
+
+        /* reserve bad_dma_address in case it's a legal address */
+        iommu_range_reserve(tbl, bad_dma_address, 1);
+
+        /* avoid the BIOS/VGA first 640KB-1MB region */
+        start = (640 * 1024);
+        npages = ((1024 - 640) * 1024) >> PAGE_SHIFT;
+        iommu_range_reserve(tbl, start, npages);
+
+        /* reserve the two PCI peripheral memory regions in IO space */
+        calgary_reserve_peripheral_mem_1(dev);
+        calgary_reserve_peripheral_mem_2(dev);
+}
+
+static int __init calgary_setup_tar(struct pci_dev *dev, void __iomem *bbar)
+{
+        u64 val64;
+        u64 table_phys;
+        void __iomem *target;
+        int ret;
+        struct iommu_table *tbl;
+
+        /* build TCE tables for each PHB */
+        ret = build_tce_table(dev, bbar);
+        if (ret)
+                return ret;
+
+        calgary_reserve_regions(dev);
+
+        /* set TARs for each PHB */
+        target = calgary_reg(bbar, tar_offset(dev->bus->number));
+        val64 = be64_to_cpu(readq(target));
+
+        /* zero out all TAR bits under sw control */
+        val64 &= ~TAR_SW_BITS;
+
+        tbl = dev->sysdata;
+        table_phys = (u64)__pa(tbl->it_base);
+        val64 |= table_phys;
+
+        BUG_ON(specified_table_size > TCE_TABLE_SIZE_8M);
+        val64 |= (u64) specified_table_size;
+
+        tbl->tar_val = cpu_to_be64(val64);
+        writeq(tbl->tar_val, target);
+        readq(target); /* flush */
+
+        return 0;
+}
+
+static void __init calgary_free_tar(struct pci_dev *dev)
+{
+        u64 val64;
+        struct iommu_table *tbl = dev->sysdata;
+        void __iomem *target;
+
+        target = calgary_reg(tbl->bbar, tar_offset(dev->bus->number));
+        val64 = be64_to_cpu(readq(target));
+        val64 &= ~TAR_SW_BITS;
+        writeq(cpu_to_be64(val64), target);
+        readq(target); /* flush */
+
+        kfree(tbl);
+        dev->sysdata = NULL;
+}
+
+static void calgary_watchdog(unsigned long data)
+{
+        struct pci_dev *dev = (struct pci_dev *)data;
+        struct iommu_table *tbl = dev->sysdata;
+        void __iomem *bbar = tbl->bbar;
+        u32 val32;
+        void __iomem *target;
+
+        target = calgary_reg(bbar, phb_offset(tbl->it_busno) | PHB_CSR_OFFSET);
+        val32 = be32_to_cpu(readl(target));
+
+        /* If no error, the agent ID in the CSR is not valid */
+        if (val32 & CSR_AGENT_MASK) {
+                printk(KERN_EMERG "calgary_watchdog: DMA error on bus %d, "
+                                  "CSR = %#x\n", dev->bus->number, val32);
+                writel(0, target);
+
+                /* Disable bus that caused the error */
+                target = calgary_reg(bbar, phb_offset(tbl->it_busno) |
+                                           PHB_CONFIG_RW_OFFSET);
+                val32 = be32_to_cpu(readl(target));
+                val32 |= PHB_SLOT_DISABLE;
+                writel(cpu_to_be32(val32), target);
+                readl(target); /* flush */
+        } else {
+                /* Reset the timer */
+                mod_timer(&tbl->watchdog_timer, jiffies + 2 * HZ);
+        }
+}
+
+static void __init calgary_enable_translation(struct pci_dev *dev)
+{
+        u32 val32;
+        unsigned char busnum;
+        void __iomem *target;
+        void __iomem *bbar;
+        struct iommu_table *tbl;
+
+        busnum = dev->bus->number;
+        tbl = dev->sysdata;
+        bbar = tbl->bbar;
+
+        /* enable TCE in PHB Config Register */
+        target = calgary_reg(bbar, phb_offset(busnum) | PHB_CONFIG_RW_OFFSET);
+        val32 = be32_to_cpu(readl(target));
+        val32 |= PHB_TCE_ENABLE | PHB_DAC_DISABLE | PHB_MCSR_ENABLE;
+
+        printk(KERN_INFO "Calgary: enabling translation on PHB %d\n", busnum);
+        printk(KERN_INFO "Calgary: errant DMAs will now be prevented on this "
+               "bus.\n");
+
+        writel(cpu_to_be32(val32), target);
+        readl(target); /* flush */
+
+        init_timer(&tbl->watchdog_timer);
+        tbl->watchdog_timer.function = &calgary_watchdog;
+        tbl->watchdog_timer.data = (unsigned long)dev;
+        mod_timer(&tbl->watchdog_timer, jiffies);
+}
+
+static void __init calgary_disable_translation(struct pci_dev *dev)
+{
+        u32 val32;
+        unsigned char busnum;
+        void __iomem *target;
+        void __iomem *bbar;
+        struct iommu_table *tbl;
+
+        busnum = dev->bus->number;
+        tbl = dev->sysdata;
+        bbar = tbl->bbar;
+
+        /* disable TCE in PHB Config Register */
+        target = calgary_reg(bbar, phb_offset(busnum) | PHB_CONFIG_RW_OFFSET);
+        val32 = be32_to_cpu(readl(target));
+        val32 &= ~(PHB_TCE_ENABLE | PHB_DAC_DISABLE | PHB_MCSR_ENABLE);
+
+        printk(KERN_INFO "Calgary: disabling translation on PHB %d!\n", busnum);
+        writel(cpu_to_be32(val32), target);
+        readl(target); /* flush */
+
+        del_timer_sync(&tbl->watchdog_timer);
+}
+
+static inline unsigned int __init locate_register_space(struct pci_dev *dev)
+{
+        int rionodeid;
+        u32 address;
+
+        rionodeid = (dev->bus->number % 15 > 4) ? 3 : 2;
+        /*
+         * register space address calculation as follows:
+         * FE0MB-8MB*OneBasedChassisNumber+1MB*(RioNodeId-ChassisBase)
+         * ChassisBase is always zero for x366/x260/x460
+         * RioNodeId is 2 for first Calgary, 3 for second Calgary
+         */
+        address = START_ADDRESS -
+                (0x800000 * (ONE_BASED_CHASSIS_NUM + dev->bus->number / 15)) +
+                (0x100000) * (rionodeid - CHASSIS_BASE);
+        return address;
+}
+
+static int __init calgary_init_one_nontraslated(struct pci_dev *dev)
+{
+        dev->sysdata = NULL;
+        dev->bus->self = dev;
+
+        return 0;
+}
+
+static int __init calgary_init_one(struct pci_dev *dev)
+{
+        u32 address;
+        void __iomem *bbar;
+        int ret;
+
+        address = locate_register_space(dev);
+        /* map entire 1MB of Calgary config space */
+        bbar = ioremap_nocache(address, 1024 * 1024);
+        if (!bbar) {
+                ret = -ENODATA;
+                goto done;
+        }
+
+        ret = calgary_setup_tar(dev, bbar);
+        if (ret)
+                goto iounmap;
+
+        dev->bus->self = dev;
+        calgary_enable_translation(dev);
+
+        return 0;
+
+iounmap:
+        iounmap(bbar);
+done:
+        return ret;
+}
+
+static int __init calgary_init(void)
+{
+        int i, ret = -ENODEV;
+        struct pci_dev *dev = NULL;
+
+        for (i = 0; i <= num_online_nodes() * MAX_NUM_OF_PHBS; i++) {
+                dev = pci_get_device(PCI_VENDOR_ID_IBM,
+                                     PCI_DEVICE_ID_IBM_CALGARY,
+                                     dev);
+                if (!dev)
+                        break;
+                if (!translate_phb(dev)) {
+                        calgary_init_one_nontraslated(dev);
+                        continue;
+                }
+                if (!tce_table_kva[i] && !translate_empty_slots) {
+                        pci_dev_put(dev);
+                        continue;
+                }
+                ret = calgary_init_one(dev);
+                if (ret)
+                        goto error;
+        }
+
+        return ret;
+
+error:
+        for (i--; i >= 0; i--) {
+                dev = pci_find_device_reverse(PCI_VENDOR_ID_IBM,
+                                              PCI_DEVICE_ID_IBM_CALGARY,
+                                              dev);
+                if (!translate_phb(dev)) {
+                        pci_dev_put(dev);
+                        continue;
+                }
+                if (!tce_table_kva[i] && !translate_empty_slots)
+                        continue;
+                calgary_disable_translation(dev);
+                calgary_free_tar(dev);
+                pci_dev_put(dev);
+        }
+
+        return ret;
+}
+
+static inline int __init determine_tce_table_size(u64 ram)
+{
+        int ret;
+
+        if (specified_table_size != TCE_TABLE_SIZE_UNSPECIFIED)
+                return specified_table_size;
+
+        /*
+         * Table sizes are from 0 to 7 (TCE_TABLE_SIZE_64K to
+         * TCE_TABLE_SIZE_8M). Table size 0 has 8K entries and each
+         * larger table size has twice as many entries, so shift the
+         * max ram address by 13 to divide by 8K and then look at the
+         * order of the result to choose between 0-7.
+         */
+        ret = get_order(ram >> 13);
+        if (ret > TCE_TABLE_SIZE_8M)
+                ret = TCE_TABLE_SIZE_8M;
+
+        return ret;
+}
+
+void __init detect_calgary(void)
+{
+        u32 val;
+        int bus, table_idx;
+        void *tbl;
+        int detected = 0;
+
+        /*
+         * if the user specified iommu=off or iommu=soft or we found
+         * another HW IOMMU already, bail out.
+         */
+        if (swiotlb || no_iommu || iommu_detected)
+                return;
+
+        specified_table_size = determine_tce_table_size(end_pfn * PAGE_SIZE);
+
+        for (bus = 0, table_idx = 0;
+             bus <= num_online_nodes() * MAX_PHB_BUS_NUM;
+             bus++) {
+                BUG_ON(bus > MAX_NUMNODES * MAX_PHB_BUS_NUM);
+                if (read_pci_config(bus, 0, 0, 0) != PCI_VENDOR_DEVICE_ID_CALGARY)
+                        continue;
+                if (test_bit(bus, translation_disabled)) {
+                        printk(KERN_INFO "Calgary: translation is disabled for "
+                               "PHB 0x%x\n", bus);
+                        /* skip this phb, don't allocate a tbl for it */
+                        tce_table_kva[table_idx] = NULL;
+                        table_idx++;
+                        continue;
+                }
+                /*
+                 * scan the first slot of the PCI bus to see if there
+                 * are any devices present
+                 */
+                val = read_pci_config(bus, 1, 0, 0);
+                if (val != 0xffffffff || translate_empty_slots) {
+                        tbl = alloc_tce_table();
+                        if (!tbl)
+                                goto cleanup;
+                        detected = 1;
+                } else
+                        tbl = NULL;
+
+                tce_table_kva[table_idx] = tbl;
+                table_idx++;
+        }
+
+        if (detected) {
+                iommu_detected = 1;
+                calgary_detected = 1;
+                printk(KERN_INFO "PCI-DMA: Calgary IOMMU detected. "
+                       "TCE table spec is %d.\n", specified_table_size);
+        }
+        return;
+
+cleanup:
+        for (--table_idx; table_idx >= 0; --table_idx)
+                if (tce_table_kva[table_idx])
+                        free_tce_table(tce_table_kva[table_idx]);
+}
+
+int __init calgary_iommu_init(void)
+{
+        int ret;
+
+        if (no_iommu || swiotlb)
+                return -ENODEV;
+
+        if (!calgary_detected)
+                return -ENODEV;
+
+        /* ok, we're trying to use Calgary - let's roll */
+        printk(KERN_INFO "PCI-DMA: Using Calgary IOMMU\n");
+
+        ret = calgary_init();
+        if (ret) {
+                printk(KERN_ERR "PCI-DMA: Calgary init failed %d, "
+                       "falling back to no_iommu\n", ret);
+                if (end_pfn > MAX_DMA32_PFN)
+                        printk(KERN_ERR "WARNING more than 4GB of memory, "
+                                        "32bit PCI may malfunction.\n");
+                return ret;
+        }
+
+        force_iommu = 1;
+        dma_ops = &calgary_dma_ops;
+
+        return 0;
+}
+
+static int __init calgary_parse_options(char *p)
+{
+        unsigned int bridge;
+        size_t len;
+        char* endp;
+
+        while (*p) {
+                if (!strncmp(p, "64k", 3))
+                        specified_table_size = TCE_TABLE_SIZE_64K;
+                else if (!strncmp(p, "128k", 4))
+                        specified_table_size = TCE_TABLE_SIZE_128K;
+                else if (!strncmp(p, "256k", 4))
+                        specified_table_size = TCE_TABLE_SIZE_256K;
+                else if (!strncmp(p, "512k", 4))
+                        specified_table_size = TCE_TABLE_SIZE_512K;
+                else if (!strncmp(p, "1M", 2))
+                        specified_table_size = TCE_TABLE_SIZE_1M;
+                else if (!strncmp(p, "2M", 2))
+                        specified_table_size = TCE_TABLE_SIZE_2M;
+                else if (!strncmp(p, "4M", 2))
+                        specified_table_size = TCE_TABLE_SIZE_4M;
+                else if (!strncmp(p, "8M", 2))
+                        specified_table_size = TCE_TABLE_SIZE_8M;
+
+                len = strlen("translate_empty_slots");
+                if (!strncmp(p, "translate_empty_slots", len))
+                        translate_empty_slots = 1;
+
+                len = strlen("disable");
+                if (!strncmp(p, "disable", len)) {
+                        p += len;
+                        if (*p == '=')
+                                ++p;
+                        if (*p == '\0')
+                                break;
+                        bridge = simple_strtol(p, &endp, 0);
+                        if (p == endp)
+                                break;
+
+                        if (bridge <= (num_online_nodes() * MAX_PHB_BUS_NUM)) {
+                                printk(KERN_INFO "Calgary: disabling "
+                                       "translation for PHB 0x%x\n", bridge);
+                                set_bit(bridge, translation_disabled);
+                        }
+                }
+
+                p = strpbrk(p, ",");
+                if (!p)
+                        break;
+
+                p++; /* skip ',' */
+        }
+        return 1;
+}
+__setup("calgary=", calgary_parse_options);