Initial import

1 files changed, 207 insertions, 0 deletions

diff --git a/arch/m68k/sun3x/dvma.c b/arch/m68k/sun3x/dvma.c
new file mode 100644
index 000000000..d5ddcdaa2
--- /dev/null
+++ b/arch/m68k/sun3x/dvma.c
@@ -0,0 +1,207 @@
+/*
+ * 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/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(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);
+	}
+
+}
+