1 files changed, 208 insertions, 0 deletions

diff --git a/arch/m68k/sun3x/dvma.c b/arch/m68k/sun3x/dvma.c
new file mode 100644
index 000000000000..32e55adfeb8e
--- /dev/null
+++ b/arch/m68k/sun3x/dvma.c
@@ -0,0 +1,208 @@
+/*
+ * Virtual DMA allocation
+ *
+ * (C) 1999 Thomas Bogendoerfer (tsbogend@alpha.franken.de)
+ *
+ * 11/26/2000 -- disabled the existing code because it didn't work for
+ * me in 2.4.  Replaced with a significantly more primitive version
+ * similar to the sun3 code.  the old functionality was probably more
+ * desirable, but....   -- Sam Creasey (sammy@oh.verio.com)
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/bitops.h>
+#include <linux/mm.h>
+#include <linux/bootmem.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+
+#include <asm/sun3x.h>
+#include <asm/dvma.h>
+#include <asm/io.h>
+#include <asm/page.h>
+#include <asm/pgtable.h>
+#include <asm/pgalloc.h>
+
+/* IOMMU support */
+
+#define IOMMU_ADDR_MASK            0x03ffe000
+#define IOMMU_CACHE_INHIBIT        0x00000040
+#define IOMMU_FULL_BLOCK           0x00000020
+#define IOMMU_MODIFIED             0x00000010
+#define IOMMU_USED                 0x00000008
+#define IOMMU_WRITE_PROTECT        0x00000004
+#define IOMMU_DT_MASK              0x00000003
+#define IOMMU_DT_INVALID           0x00000000
+#define IOMMU_DT_VALID             0x00000001
+#define IOMMU_DT_BAD               0x00000002
+
+
+static volatile unsigned long *iommu_pte = (unsigned long *)SUN3X_IOMMU;
+
+
+#define dvma_entry_paddr(index)         (iommu_pte[index] & IOMMU_ADDR_MASK)
+#define dvma_entry_vaddr(index,paddr)   ((index << DVMA_PAGE_SHIFT) |  \
+                                         (paddr & (DVMA_PAGE_SIZE-1)))
+#if 0
+#define dvma_entry_set(index,addr)      (iommu_pte[index] =            \
+                                            (addr & IOMMU_ADDR_MASK) | \
+                                             IOMMU_DT_VALID | IOMMU_CACHE_INHIBIT)
+#else
+#define dvma_entry_set(index,addr)      (iommu_pte[index] =            \
+                                            (addr & IOMMU_ADDR_MASK) | \
+                                             IOMMU_DT_VALID)
+#endif
+#define dvma_entry_clr(index)           (iommu_pte[index] = IOMMU_DT_INVALID)
+#define dvma_entry_hash(addr)           ((addr >> DVMA_PAGE_SHIFT) ^ \
+                                         ((addr & 0x03c00000) >>     \
+                                                (DVMA_PAGE_SHIFT+4)))
+
+#undef DEBUG
+
+#ifdef DEBUG
+/* code to print out a dvma mapping for debugging purposes */
+void dvma_print (unsigned long dvma_addr)
+{
+
+        unsigned long index;
+
+        index = dvma_addr >> DVMA_PAGE_SHIFT;
+
+        printk("idx %lx dvma_addr %08lx paddr %08lx\n", index, dvma_addr,
+               dvma_entry_paddr(index));
+
+
+}
+#endif
+
+
+/* create a virtual mapping for a page assigned within the IOMMU
+   so that the cpu can reach it easily */
+inline int dvma_map_cpu(unsigned long kaddr,
+                               unsigned long vaddr, int len)
+{
+        pgd_t *pgd;
+        unsigned long end;
+        int ret = 0;
+
+        kaddr &= PAGE_MASK;
+        vaddr &= PAGE_MASK;
+
+        end = PAGE_ALIGN(vaddr + len);
+
+#ifdef DEBUG
+        printk("dvma: mapping kern %08lx to virt %08lx\n",
+               kaddr, vaddr);
+#endif
+        pgd = pgd_offset_k(vaddr);
+
+        do {
+                pmd_t *pmd;
+                unsigned long end2;
+
+                if((pmd = pmd_alloc(&init_mm, pgd, vaddr)) == NULL) {
+                        ret = -ENOMEM;
+                        goto out;
+                }
+
+                if((end & PGDIR_MASK) > (vaddr & PGDIR_MASK))
+                        end2 = (vaddr + (PGDIR_SIZE-1)) & PGDIR_MASK;
+                else
+                        end2 = end;
+
+                do {
+                        pte_t *pte;
+                        unsigned long end3;
+
+                        if((pte = pte_alloc_kernel(&init_mm, pmd, vaddr)) == NULL) {
+                                ret = -ENOMEM;
+                                goto out;
+                        }
+
+                        if((end2 & PMD_MASK) > (vaddr & PMD_MASK))
+                                end3 = (vaddr + (PMD_SIZE-1)) & PMD_MASK;
+                        else
+                                end3 = end2;
+
+                        do {
+#ifdef DEBUG
+                                printk("mapping %08lx phys to %08lx\n",
+                                       __pa(kaddr), vaddr);
+#endif
+                                set_pte(pte, pfn_pte(virt_to_pfn(kaddr),
+                                                     PAGE_KERNEL));
+                                pte++;
+                                kaddr += PAGE_SIZE;
+                                vaddr += PAGE_SIZE;
+                        } while(vaddr < end3);
+
+                } while(vaddr < end2);
+
+        } while(vaddr < end);
+
+        flush_tlb_all();
+
+ out:
+        return ret;
+}
+
+
+inline int dvma_map_iommu(unsigned long kaddr, unsigned long baddr,
+                                 int len)
+{
+        unsigned long end, index;
+
+        index = baddr >> DVMA_PAGE_SHIFT;
+        end = ((baddr+len) >> DVMA_PAGE_SHIFT);
+
+        if(len & ~DVMA_PAGE_MASK)
+                end++;
+
+        for(; index < end ; index++) {
+//              if(dvma_entry_use(index))
+//                      BUG();
+//              printk("mapping pa %lx to ba %lx\n", __pa(kaddr), index << DVMA_PAGE_SHIFT);
+
+                dvma_entry_set(index, __pa(kaddr));
+
+                iommu_pte[index] |= IOMMU_FULL_BLOCK;
+//              dvma_entry_inc(index);
+
+                kaddr += DVMA_PAGE_SIZE;
+        }
+
+#ifdef DEBUG
+        for(index = (baddr >> DVMA_PAGE_SHIFT); index < end; index++)
+                dvma_print(index << DVMA_PAGE_SHIFT);
+#endif
+        return 0;
+
+}
+
+void dvma_unmap_iommu(unsigned long baddr, int len)
+{
+
+        int index, end;
+
+
+        index = baddr >> DVMA_PAGE_SHIFT;
+        end = (DVMA_PAGE_ALIGN(baddr+len) >> DVMA_PAGE_SHIFT);
+
+        for(; index < end ; index++) {
+#ifdef DEBUG
+                printk("freeing bus mapping %08x\n", index << DVMA_PAGE_SHIFT);
+#endif
+#if 0
+                if(!dvma_entry_use(index))
+                        printk("dvma_unmap freeing unused entry %04x\n",
+                               index);
+                else
+                        dvma_entry_dec(index);
+#endif
+                dvma_entry_clr(index);
+        }
+
+}
+