1// SPDX-License-Identifier: GPL-2.0
2/*
3 * linux/arch/m68k/sun3/dvma.c
4 *
5 * Written by Sam Creasey
6 *
7 * Sun3 IOMMU routines used for dvma accesses.
8 *
9 */
10
11#include <linux/init.h>
12#include <linux/kernel.h>
13#include <linux/mm.h>
14#include <linux/memblock.h>
15#include <linux/list.h>
16#include <asm/page.h>
17#include <asm/sun3mmu.h>
18#include <asm/dvma.h>
19
20
21static unsigned long ptelist[120];
22
23static 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(page_nr: virt_to_pfn((void *)kaddr), PAGE_KERNEL);
33 pte = pte_val(pte: ptep);
34// pr_info("dvma_remap: addr %lx -> %lx pte %08lx\n", kaddr, vaddr, pte);
35 if(ptelist[(vaddr & 0xff000) >> PAGE_SHIFT] != pte) {
36 sun3_put_pte(vaddr, pte);
37 ptelist[(vaddr & 0xff000) >> PAGE_SHIFT] = pte;
38 }
39
40 return (vaddr + (kaddr & ~PAGE_MASK));
41
42}
43
44int dvma_map_iommu(unsigned long kaddr, unsigned long baddr,
45 int len)
46{
47
48 unsigned long end;
49 unsigned long vaddr;
50
51 vaddr = dvma_btov(baddr);
52
53 end = vaddr + len;
54
55 while(vaddr < end) {
56 dvma_page(kaddr, vaddr);
57 kaddr += PAGE_SIZE;
58 vaddr += PAGE_SIZE;
59 }
60
61 return 0;
62
63}
64
65void __init sun3_dvma_init(void)
66{
67 memset(ptelist, 0, sizeof(ptelist));
68}
69

source code of linux/arch/m68k/sun3/dvma.c