LXR linux/arch/m68k/sun3/dvma.c

   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(virt_to_pfn(kaddr), PAGE_KERNEL);
  33        pte = pte_val(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