LXR linux/arch/powerpc/platforms/cell/spufs/spu

   1/*
   2 * utils.h: Utilities for SPU-side of the context switch operation.
   3 *
   4 * (C) Copyright IBM 2005
   5 *
   6 * This program is free software; you can redistribute it and/or modify
   7 * it under the terms of the GNU General Public License as published by
   8 * the Free Software Foundation; either version 2, or (at your option)
   9 * any later version.
  10 *
  11 * This program is distributed in the hope that it will be useful,
  12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  14 * GNU General Public License for more details.
  15 *
  16 * You should have received a copy of the GNU General Public License
  17 * along with this program; if not, write to the Free Software
  18 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  19 */
  20
  21#ifndef _SPU_CONTEXT_UTILS_H_
  22#define _SPU_CONTEXT_UTILS_H_
  23
  24/*
  25 * 64-bit safe EA.
  26 */
  27typedef union {
  28        unsigned long long ull;
  29        unsigned int ui[2];
  30} addr64;
  31
  32/*
  33 * 128-bit register template.
  34 */
  35typedef union {
  36        unsigned int slot[4];
  37        vector unsigned int v;
  38} spu_reg128v;
  39
  40/*
  41 * DMA list structure.
  42 */
  43struct dma_list_elem {
  44        unsigned int size;
  45        unsigned int ea_low;
  46};
  47
  48/*
  49 * Declare storage for 8-byte aligned DMA list.
  50 */
  51struct dma_list_elem dma_list[15] __attribute__ ((aligned(8)));
  52
  53/*
  54 * External definition for storage
  55 * declared in crt0.
  56 */
  57extern spu_reg128v regs_spill[NR_SPU_SPILL_REGS];
  58
  59/*
  60 * Compute LSCSA byte offset for a given field.
  61 */
  62static struct spu_lscsa *dummy = (struct spu_lscsa *)0;
  63#define LSCSA_BYTE_OFFSET(_field)  \
  64        ((char *)(&(dummy->_field)) - (char *)(&(dummy->gprs[0].slot[0])))
  65#define LSCSA_QW_OFFSET(_field)  (LSCSA_BYTE_OFFSET(_field) >> 4)
  66
  67static inline void set_event_mask(void)
  68{
  69        unsigned int event_mask = 0;
  70
  71        /* Save, Step 4:
  72         * Restore, Step 1:
  73         *    Set the SPU_RdEventMsk channel to zero to mask
  74         *    all events.
  75         */
  76        spu_writech(SPU_WrEventMask, event_mask);
  77}
  78
  79static inline void set_tag_mask(void)
  80{
  81        unsigned int tag_mask = 1;
  82
  83        /* Save, Step 5:
  84         * Restore, Step 2:
  85         *    Set the SPU_WrTagMsk channel to '01' to unmask
  86         *    only tag group 0.
  87         */
  88        spu_writech(MFC_WrTagMask, tag_mask);
  89}
  90
  91static inline void build_dma_list(addr64 lscsa_ea)
  92{
  93        unsigned int ea_low;
  94        int i;
  95
  96        /* Save, Step 6:
  97         * Restore, Step 3:
  98         *    Update the effective address for the CSA in the
  99         *    pre-canned DMA-list in local storage.
 100         */
 101        ea_low = lscsa_ea.ui[1];
 102        ea_low += LSCSA_BYTE_OFFSET(ls[16384]);
 103
 104        for (i = 0; i < 15; i++, ea_low += 16384) {
 105                dma_list[i].size = 16384;
 106                dma_list[i].ea_low = ea_low;
 107        }
 108}
 109
 110static inline void enqueue_putllc(addr64 lscsa_ea)
 111{
 112        unsigned int ls = 0;
 113        unsigned int size = 128;
 114        unsigned int tag_id = 0;
 115        unsigned int cmd = 0xB4;        /* PUTLLC */
 116
 117        /* Save, Step 12:
 118         * Restore, Step 7:
 119         *    Send a PUTLLC (tag 0) command to the MFC using
 120         *    an effective address in the CSA in order to
 121         *    remove any possible lock-line reservation.
 122         */
 123        spu_writech(MFC_LSA, ls);
 124        spu_writech(MFC_EAH, lscsa_ea.ui[0]);
 125        spu_writech(MFC_EAL, lscsa_ea.ui[1]);
 126        spu_writech(MFC_Size, size);
 127        spu_writech(MFC_TagID, tag_id);
 128        spu_writech(MFC_Cmd, cmd);
 129}
 130
 131static inline void set_tag_update(void)
 132{
 133        unsigned int update_any = 1;
 134
 135        /* Save, Step 15:
 136         * Restore, Step 8:
 137         *    Write the MFC_TagUpdate channel with '01'.
 138         */
 139        spu_writech(MFC_WrTagUpdate, update_any);
 140}
 141
 142static inline void read_tag_status(void)
 143{
 144        /* Save, Step 16:
 145         * Restore, Step 9:
 146         *    Read the MFC_TagStat channel data.
 147         */
 148        spu_readch(MFC_RdTagStat);
 149}
 150
 151static inline void read_llar_status(void)
 152{
 153        /* Save, Step 17:
 154         * Restore, Step 10:
 155         *    Read the MFC_AtomicStat channel data.
 156         */
 157        spu_readch(MFC_RdAtomicStat);
 158}
 159
 160#endif                          /* _SPU_CONTEXT_UTILS_H_ */
 161