xref: /openbmc/linux/arch/m68k/sun3/dvma.c (revision 8730046c)
1 /*
2  * linux/arch/m68k/sun3/dvma.c
3  *
4  * Written by Sam Creasey
5  *
6  * Sun3 IOMMU routines used for dvma accesses.
7  *
8  */
9 
10 #include <linux/init.h>
11 #include <linux/kernel.h>
12 #include <linux/mm.h>
13 #include <linux/bootmem.h>
14 #include <linux/list.h>
15 #include <asm/page.h>
16 #include <asm/pgtable.h>
17 #include <asm/sun3mmu.h>
18 #include <asm/dvma.h>
19 
20 
21 static unsigned long ptelist[120];
22 
23 static unsigned long dvma_page(unsigned long kaddr, unsigned long vaddr)
24 {
25 	unsigned long pte;
26 	unsigned long j;
27 	pte_t ptep;
28 
29 	j = *(volatile unsigned long *)kaddr;
30 	*(volatile unsigned long *)kaddr = j;
31 
32 	ptep = pfn_pte(virt_to_pfn(kaddr), PAGE_KERNEL);
33 	pte = pte_val(ptep);
34 //		printk("dvma_remap: addr %lx -> %lx pte %08lx len %x\n",
35 //		       kaddr, vaddr, pte, len);
36 	if(ptelist[(vaddr & 0xff000) >> PAGE_SHIFT] != pte) {
37 		sun3_put_pte(vaddr, pte);
38 		ptelist[(vaddr & 0xff000) >> PAGE_SHIFT] = pte;
39 	}
40 
41 	return (vaddr + (kaddr & ~PAGE_MASK));
42 
43 }
44 
45 int dvma_map_iommu(unsigned long kaddr, unsigned long baddr,
46 			      int len)
47 {
48 
49 	unsigned long end;
50 	unsigned long vaddr;
51 
52 	vaddr = dvma_btov(baddr);
53 
54 	end = vaddr + len;
55 
56 	while(vaddr < end) {
57 		dvma_page(kaddr, vaddr);
58 		kaddr += PAGE_SIZE;
59 		vaddr += PAGE_SIZE;
60 	}
61 
62 	return 0;
63 
64 }
65 
66 void __init sun3_dvma_init(void)
67 {
68 	memset(ptelist, 0, sizeof(ptelist));
69 }
70