[SPARC64]: Don't be picky about virtual-dma values on sun4v.

Handle arbitrary base and length values as long as they
are multiples of IO_PAGE_SIZE.

Bug found by Arun Kumar Rao.

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 10 insertions, 26 deletions

diff --git a/arch/sparc64/kernel/pci_sun4v.c b/arch/sparc64/kernel/pci_sun4v.c
index 044e8ec4c0f5..62e4d047dbc0 100644
--- a/arch/sparc64/kernel/pci_sun4v.c
+++ b/arch/sparc64/kernel/pci_sun4v.c
@@ -12,6 +12,7 @@
 #include <linux/percpu.h>
 #include <linux/irq.h>
 #include <linux/msi.h>
+#include <linux/log2.h>
 
 #include <asm/iommu.h>
 #include <asm/irq.h>
@@ -638,9 +639,8 @@ static void pci_sun4v_iommu_init(struct pci_pbm_info *pbm)
 {
         struct iommu *iommu = pbm->iommu;
         struct property *prop;
-        unsigned long num_tsb_entries, sz;
+        unsigned long num_tsb_entries, sz, tsbsize;
         u32 vdma[2], dma_mask, dma_offset;
-        int tsbsize;
 
         prop = of_find_property(pbm->prom_node, "virtual-dma", NULL);
         if (prop) {
@@ -654,31 +654,15 @@ static void pci_sun4v_iommu_init(struct pci_pbm_info *pbm)
                 vdma[1] = 0x80000000;
         }
 
-        dma_mask = vdma[0];
-        switch (vdma[1]) {
-                case 0x20000000:
-                        dma_mask |= 0x1fffffff;
-                        tsbsize = 64;
-                        break;
-
-                case 0x40000000:
-                        dma_mask |= 0x3fffffff;
-                        tsbsize = 128;
-                        break;
-
-                case 0x80000000:
-                        dma_mask |= 0x7fffffff;
-                        tsbsize = 256;
-                        break;
-
-                default:
-                        prom_printf("PCI-SUN4V: strange virtual-dma size.\n");
-                        prom_halt();
+        if ((vdma[0] | vdma[1]) & ~IO_PAGE_MASK) {
+                prom_printf("PCI-SUN4V: strange virtual-dma[%08x:%08x].\n",
+                            vdma[0], vdma[1]);
+                prom_halt();
         };
 
-        tsbsize *= (8 * 1024);
-
-        num_tsb_entries = tsbsize / sizeof(iopte_t);
+        dma_mask = (roundup_pow_of_two(vdma[1]) - 1UL);
+        num_tsb_entries = vdma[1] / IO_PAGE_SIZE;
+        tsbsize = num_tsb_entries * sizeof(iopte_t);
 
         dma_offset = vdma[0];
 
@@ -689,7 +673,7 @@ static void pci_sun4v_iommu_init(struct pci_pbm_info *pbm)
         iommu->dma_addr_mask = dma_mask;
 
         /* Allocate and initialize the free area map.  */
-        sz = num_tsb_entries / 8;
+        sz = (num_tsb_entries + 7) / 8;
         sz = (sz + 7UL) & ~7UL;
         iommu->arena.map = kzalloc(sz, GFP_KERNEL);
         if (!iommu->arena.map) {