1 files changed, 107 insertions, 53 deletions

diff --git a/arch/x86/kernel/pci-calgary_64.c b/arch/x86/kernel/pci-calgary_64.c
index 6959b5c45df4..b67a4b1d4eae 100644
--- a/arch/x86/kernel/pci-calgary_64.c
+++ b/arch/x86/kernel/pci-calgary_64.c
@@ -29,6 +29,7 @@
 #include <linux/mm.h>
 #include <linux/spinlock.h>
 #include <linux/string.h>
+#include <linux/crash_dump.h>
 #include <linux/dma-mapping.h>
 #include <linux/bitops.h>
 #include <linux/pci_ids.h>
@@ -36,7 +37,8 @@
 #include <linux/delay.h>
 #include <linux/scatterlist.h>
 #include <linux/iommu-helper.h>
-#include <asm/gart.h>
+
+#include <asm/iommu.h>
 #include <asm/calgary.h>
 #include <asm/tce.h>
 #include <asm/pci-direct.h>
@@ -167,6 +169,8 @@ static void calgary_dump_error_regs(struct iommu_table *tbl);
 static void calioc2_handle_quirks(struct iommu_table *tbl, struct pci_dev *dev);
 static void calioc2_tce_cache_blast(struct iommu_table *tbl);
 static void calioc2_dump_error_regs(struct iommu_table *tbl);
+static void calgary_init_bitmap_from_tce_table(struct iommu_table *tbl);
+static void get_tce_space_from_tar(void);
 
 static struct cal_chipset_ops calgary_chip_ops = {
         .handle_quirks = calgary_handle_quirks,
@@ -410,22 +414,6 @@ static void calgary_unmap_sg(struct device *dev,
         }
 }
 
-static int calgary_nontranslate_map_sg(struct device* dev,
-        struct scatterlist *sg, int nelems, int direction)
-{
-        struct scatterlist *s;
-        int i;
-
-        for_each_sg(sg, s, nelems, i) {
-                struct page *p = sg_page(s);
-
-                BUG_ON(!p);
-                s->dma_address = virt_to_bus(sg_virt(s));
-                s->dma_length = s->length;
-        }
-        return nelems;
-}
-
 static int calgary_map_sg(struct device *dev, struct scatterlist *sg,
         int nelems, int direction)
 {
@@ -436,9 +424,6 @@ static int calgary_map_sg(struct device *dev, struct scatterlist *sg,
         unsigned long entry;
         int i;
 
-        if (!translation_enabled(tbl))
-                return calgary_nontranslate_map_sg(dev, sg, nelems, direction);
-
         for_each_sg(sg, s, nelems, i) {
                 BUG_ON(!sg_page(s));
 
@@ -474,7 +459,6 @@ error:
 static dma_addr_t calgary_map_single(struct device *dev, phys_addr_t paddr,
         size_t size, int direction)
 {
-        dma_addr_t dma_handle = bad_dma_address;
         void *vaddr = phys_to_virt(paddr);
         unsigned long uaddr;
         unsigned int npages;
@@ -483,12 +467,7 @@ static dma_addr_t calgary_map_single(struct device *dev, phys_addr_t paddr,
         uaddr = (unsigned long)vaddr;
         npages = num_dma_pages(uaddr, size);
 
-        if (translation_enabled(tbl))
-                dma_handle = iommu_alloc(dev, tbl, vaddr, npages, direction);
-        else
-                dma_handle = virt_to_bus(vaddr);
-
-        return dma_handle;
+        return iommu_alloc(dev, tbl, vaddr, npages, direction);
 }
 
 static void calgary_unmap_single(struct device *dev, dma_addr_t dma_handle,
@@ -497,9 +476,6 @@ static void calgary_unmap_single(struct device *dev, dma_addr_t dma_handle,
         struct iommu_table *tbl = find_iommu_table(dev);
         unsigned int npages;
 
-        if (!translation_enabled(tbl))
-                return;
-
         npages = num_dma_pages(dma_handle, size);
         iommu_free(tbl, dma_handle, npages);
 }
@@ -522,18 +498,12 @@ static void* calgary_alloc_coherent(struct device *dev, size_t size,
                 goto error;
         memset(ret, 0, size);
 
-        if (translation_enabled(tbl)) {
-                /* set up tces to cover the allocated range */
-                mapping = iommu_alloc(dev, 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);
-
+        /* set up tces to cover the allocated range */
+        mapping = iommu_alloc(dev, tbl, ret, npages, DMA_BIDIRECTIONAL);
+        if (mapping == bad_dma_address)
+                goto free;
+        *dma_handle = mapping;
         return ret;
-
 free:
         free_pages((unsigned long)ret, get_order(size));
         ret = NULL;
@@ -541,7 +511,7 @@ error:
         return ret;
 }
 
-static const struct dma_mapping_ops calgary_dma_ops = {
+static struct dma_mapping_ops calgary_dma_ops = {
         .alloc_coherent = calgary_alloc_coherent,
         .map_single = calgary_map_single,
         .unmap_single = calgary_unmap_single,
@@ -830,7 +800,11 @@ static int __init calgary_setup_tar(struct pci_dev *dev, void __iomem *bbar)
 
         tbl = pci_iommu(dev->bus);
         tbl->it_base = (unsigned long)bus_info[dev->bus->number].tce_space;
-        tce_free(tbl, 0, tbl->it_size);
+
+        if (is_kdump_kernel())
+                calgary_init_bitmap_from_tce_table(tbl);
+        else
+                tce_free(tbl, 0, tbl->it_size);
 
         if (is_calgary(dev->device))
                 tbl->chip_ops = &calgary_chip_ops;
@@ -1209,6 +1183,10 @@ static int __init calgary_init(void)
         if (ret)
                 return ret;
 
+        /* Purely for kdump kernel case */
+        if (is_kdump_kernel())
+                get_tce_space_from_tar();
+
         do {
                 dev = pci_get_device(PCI_VENDOR_ID_IBM, PCI_ANY_ID, dev);
                 if (!dev)
@@ -1230,6 +1208,16 @@ static int __init calgary_init(void)
                         goto error;
         } while (1);
 
+        dev = NULL;
+        for_each_pci_dev(dev) {
+                struct iommu_table *tbl;
+
+                tbl = find_iommu_table(&dev->dev);
+
+                if (translation_enabled(tbl))
+                        dev->dev.archdata.dma_ops = &calgary_dma_ops;
+        }
+
         return ret;
 
 error:
@@ -1251,6 +1239,7 @@ error:
                 calgary_disable_translation(dev);
                 calgary_free_bus(dev);
                 pci_dev_put(dev); /* Undo calgary_init_one()'s pci_dev_get() */
+                dev->dev.archdata.dma_ops = NULL;
         } while (1);
 
         return ret;
@@ -1339,6 +1328,61 @@ static int __init calgary_bus_has_devices(int bus, unsigned short pci_dev)
         return (val != 0xffffffff);
 }
 
+/*
+ * calgary_init_bitmap_from_tce_table():
+ * Funtion for kdump case. In the second/kdump kernel initialize
+ * the bitmap based on the tce table entries obtained from first kernel
+ */
+static void calgary_init_bitmap_from_tce_table(struct iommu_table *tbl)
+{
+        u64 *tp;
+        unsigned int index;
+        tp = ((u64 *)tbl->it_base);
+        for (index = 0 ; index < tbl->it_size; index++) {
+                if (*tp != 0x0)
+                        set_bit(index, tbl->it_map);
+                tp++;
+        }
+}
+
+/*
+ * get_tce_space_from_tar():
+ * Function for kdump case. Get the tce tables from first kernel
+ * by reading the contents of the base adress register of calgary iommu
+ */
+static void get_tce_space_from_tar()
+{
+        int bus;
+        void __iomem *target;
+        unsigned long tce_space;
+
+        for (bus = 0; bus < MAX_PHB_BUS_NUM; bus++) {
+                struct calgary_bus_info *info = &bus_info[bus];
+                unsigned short pci_device;
+                u32 val;
+
+                val = read_pci_config(bus, 0, 0, 0);
+                pci_device = (val & 0xFFFF0000) >> 16;
+
+                if (!is_cal_pci_dev(pci_device))
+                        continue;
+                if (info->translation_disabled)
+                        continue;
+
+                if (calgary_bus_has_devices(bus, pci_device) ||
+                                                translate_empty_slots) {
+                        target = calgary_reg(bus_info[bus].bbar,
+                                                tar_offset(bus));
+                        tce_space = be64_to_cpu(readq(target));
+                        tce_space = tce_space & TAR_SW_BITS;
+
+                        tce_space = tce_space & (~specified_table_size);
+                        info->tce_space = (u64 *)__va(tce_space);
+                }
+        }
+        return;
+}
+
 void __init detect_calgary(void)
 {
         int bus;
@@ -1394,7 +1438,8 @@ void __init detect_calgary(void)
                 return;
         }
 
-        specified_table_size = determine_tce_table_size(max_pfn * PAGE_SIZE);
+        specified_table_size = determine_tce_table_size((is_kdump_kernel() ?
+                                        saved_max_pfn : max_pfn) * PAGE_SIZE);
 
         for (bus = 0; bus < MAX_PHB_BUS_NUM; bus++) {
                 struct calgary_bus_info *info = &bus_info[bus];
@@ -1412,10 +1457,16 @@ void __init detect_calgary(void)
 
                 if (calgary_bus_has_devices(bus, pci_device) ||
                     translate_empty_slots) {
-                        tbl = alloc_tce_table();
-                        if (!tbl)
-                                goto cleanup;
-                        info->tce_space = tbl;
+                        /*
+                         * If it is kdump kernel, find and use tce tables
+                         * from first kernel, else allocate tce tables here
+                         */
+                        if (!is_kdump_kernel()) {
+                                tbl = alloc_tce_table();
+                                if (!tbl)
+                                        goto cleanup;
+                                info->tce_space = tbl;
+                        }
                         calgary_found = 1;
                 }
         }
@@ -1430,6 +1481,10 @@ void __init detect_calgary(void)
                 printk(KERN_INFO "PCI-DMA: Calgary TCE table spec is %d, "
                        "CONFIG_IOMMU_DEBUG is %s.\n", specified_table_size,
                        debugging ? "enabled" : "disabled");
+
+                /* swiotlb for devices that aren't behind the Calgary. */
+                if (max_pfn > MAX_DMA32_PFN)
+                        swiotlb = 1;
         }
         return;
 
@@ -1446,7 +1501,7 @@ int __init calgary_iommu_init(void)
 {
         int ret;
 
-        if (no_iommu || swiotlb)
+        if (no_iommu || (swiotlb && !calgary_detected))
                 return -ENODEV;
 
         if (!calgary_detected)
@@ -1459,15 +1514,14 @@ int __init calgary_iommu_init(void)
         if (ret) {
                 printk(KERN_ERR "PCI-DMA: Calgary init failed %d, "
                        "falling back to no_iommu\n", ret);
-                if (max_pfn > MAX_DMA32_PFN)
-                        printk(KERN_ERR "WARNING more than 4GB of memory, "
-                                        "32bit PCI may malfunction.\n");
                 return ret;
         }
 
         force_iommu = 1;
         bad_dma_address = 0x0;
-        dma_ops = &calgary_dma_ops;
+        /* dma_ops is set to swiotlb or nommu */
+        if (!dma_ops)
+                dma_ops = &nommu_dma_ops;
 
         return 0;
 }