dvma.c 1.3 KB

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  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. #include <linux/init.h>
  11. #include <linux/kernel.h>
  12. #include <linux/mm.h>
  13. #include <linux/memblock.h>
  14. #include <linux/list.h>
  15. #include <asm/page.h>
  16. #include <asm/sun3mmu.h>
  17. #include <asm/dvma.h>
  18. static unsigned long ptelist[120];
  19. static unsigned long dvma_page(unsigned long kaddr, unsigned long vaddr)
  20. {
  21. unsigned long pte;
  22. unsigned long j;
  23. pte_t ptep;
  24. j = *(volatile unsigned long *)kaddr;
  25. *(volatile unsigned long *)kaddr = j;
  26. ptep = pfn_pte(virt_to_pfn(kaddr), PAGE_KERNEL);
  27. pte = pte_val(ptep);
  28. // pr_info("dvma_remap: addr %lx -> %lx pte %08lx\n", kaddr, vaddr, pte);
  29. if(ptelist[(vaddr & 0xff000) >> PAGE_SHIFT] != pte) {
  30. sun3_put_pte(vaddr, pte);
  31. ptelist[(vaddr & 0xff000) >> PAGE_SHIFT] = pte;
  32. }
  33. return (vaddr + (kaddr & ~PAGE_MASK));
  34. }
  35. int dvma_map_iommu(unsigned long kaddr, unsigned long baddr,
  36. int len)
  37. {
  38. unsigned long end;
  39. unsigned long vaddr;
  40. vaddr = dvma_btov(baddr);
  41. end = vaddr + len;
  42. while(vaddr < end) {
  43. dvma_page(kaddr, vaddr);
  44. kaddr += PAGE_SIZE;
  45. vaddr += PAGE_SIZE;
  46. }
  47. return 0;
  48. }
  49. void __init sun3_dvma_init(void)
  50. {
  51. memset(ptelist, 0, sizeof(ptelist));
  52. }