arch/sparc/include/asm/io-unit.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /* io-unit.h: Definitions for the sun4d IO-UNIT.
   3  *
   4  * Copyright (C) 1997,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
   5  */
   6 #ifndef _SPARC_IO_UNIT_H
   7 #define _SPARC_IO_UNIT_H
   8
   9 #include <linux/spinlock.h>
  10 #include <linux/pgtable.h>
  11 #include <asm/page.h>
  12
  13 /* The io-unit handles all virtual to physical address translations
  14  * that occur between the SBUS and physical memory.  Access by
  15  * the cpu to IO registers and similar go over the xdbus so are
  16  * translated by the on chip SRMMU.  The io-unit and the srmmu do
  17  * not need to have the same translations at all, in fact most
  18  * of the time the translations they handle are a disjunct set.
  19  * Basically the io-unit handles all dvma sbus activity.
  20  */
  21
  22 /* AIEEE, unlike the nice sun4m, these monsters have
  23    fixed DMA range 64M */
  24
  25 #define IOUNIT_DMA_BASE     0xfc000000 /* TOP - 64M */
  26 #define IOUNIT_DMA_SIZE     0x04000000 /* 64M */
  27 /* We use last 1M for sparc_dvma_malloc */
  28 #define IOUNIT_DVMA_SIZE    0x00100000 /* 1M */
  29
  30 /* The format of an iopte in the external page tables */
  31 #define IOUPTE_PAGE          0xffffff00 /* Physical page number (PA[35:12])     */
  32 #define IOUPTE_CACHE         0x00000080 /* Cached (in Viking/MXCC)              */
  33 /* XXX Jakub, find out how to program SBUS streaming cache on XDBUS/sun4d.
  34  * XXX Actually, all you should need to do is find out where the registers
  35  * XXX are and copy over the sparc64 implementation I wrote.  There may be
  36  * XXX some horrible hwbugs though, so be careful.  -DaveM
  37  */
  38 #define IOUPTE_STREAM        0x00000040 /* Translation can use streaming cache  */
  39 #define IOUPTE_INTRA         0x00000008 /* SBUS direct slot->slot transfer      */
  40 #define IOUPTE_WRITE         0x00000004 /* Writeable                            */
  41 #define IOUPTE_VALID         0x00000002 /* IOPTE is valid                       */
  42 #define IOUPTE_PARITY        0x00000001 /* Parity is checked during DVMA        */
  43
  44 struct iounit_struct {
  45         unsigned long           bmap[(IOUNIT_DMA_SIZE >> (PAGE_SHIFT + 3)) / sizeof(unsigned long)];
  46         spinlock_t              lock;
  47         iopte_t __iomem         *page_table;
  48         unsigned long           rotor[3];
  49         unsigned long           limit[4];
  50 };
  51
  52 #define IOUNIT_BMAP1_START      0x00000000
  53 #define IOUNIT_BMAP1_END        (IOUNIT_DMA_SIZE >> (PAGE_SHIFT + 1))
  54 #define IOUNIT_BMAP2_START      IOUNIT_BMAP1_END
  55 #define IOUNIT_BMAP2_END        IOUNIT_BMAP2_START + (IOUNIT_DMA_SIZE >> (PAGE_SHIFT + 2))
  56 #define IOUNIT_BMAPM_START      IOUNIT_BMAP2_END
  57 #define IOUNIT_BMAPM_END        ((IOUNIT_DMA_SIZE - IOUNIT_DVMA_SIZE) >> PAGE_SHIFT)
  58
  59 #endif /* !(_SPARC_IO_UNIT_H) */