1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License, Version 1.0 only 6 * (the "License"). You may not use this file except in compliance 7 * with the License. 8 * 9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 10 * or http://www.opensolaris.org/os/licensing. 11 * See the License for the specific language governing permissions 12 * and limitations under the License. 13 * 14 * When distributing Covered Code, include this CDDL HEADER in each 15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 16 * If applicable, add the following below this CDDL HEADER, with the 17 * fields enclosed by brackets "[]" replaced with your own identifying 18 * information: Portions Copyright [yyyy] [name of copyright owner] 19 * 20 * CDDL HEADER END 21 */ 22 /* 23 * Copyright 2003 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27 #pragma ident "%Z%%M% %I% %E% SMI" 28 29 #include <sys/types.h> 30 #include <sys/bitmap.h> 31 #include <assert.h> 32 #include <strings.h> 33 #include <stdlib.h> 34 35 #include <dt_regset.h> 36 37 dt_regset_t * 38 dt_regset_create(ulong_t size) 39 { 40 ulong_t n = BT_BITOUL(size + 1); /* + 1 for %r0 */ 41 dt_regset_t *drp = malloc(sizeof (dt_regset_t)); 42 43 if (drp == NULL) 44 return (NULL); 45 46 drp->dr_bitmap = malloc(sizeof (ulong_t) * n); 47 drp->dr_size = size + 1; 48 49 if (drp->dr_bitmap == NULL) { 50 dt_regset_destroy(drp); 51 return (NULL); 52 } 53 54 bzero(drp->dr_bitmap, sizeof (ulong_t) * n); 55 return (drp); 56 } 57 58 void 59 dt_regset_destroy(dt_regset_t *drp) 60 { 61 free(drp->dr_bitmap); 62 free(drp); 63 } 64 65 void 66 dt_regset_reset(dt_regset_t *drp) 67 { 68 bzero(drp->dr_bitmap, sizeof (ulong_t) * BT_BITOUL(drp->dr_size)); 69 } 70 71 int 72 dt_regset_alloc(dt_regset_t *drp) 73 { 74 ulong_t nbits = drp->dr_size - 1; 75 ulong_t maxw = nbits >> BT_ULSHIFT; 76 ulong_t wx; 77 78 for (wx = 0; wx <= maxw; wx++) { 79 if (drp->dr_bitmap[wx] != ~0UL) 80 break; 81 } 82 83 if (wx <= maxw) { 84 ulong_t maxb = (wx == maxw) ? nbits & BT_ULMASK : BT_NBIPUL - 1; 85 ulong_t word = drp->dr_bitmap[wx]; 86 ulong_t bit, bx; 87 int reg; 88 89 for (bit = 1, bx = 0; bx <= maxb; bx++, bit <<= 1) { 90 if ((word & bit) == 0) { 91 reg = (int)((wx << BT_ULSHIFT) | bx); 92 BT_SET(drp->dr_bitmap, reg); 93 return (reg); 94 } 95 } 96 } 97 98 return (-1); /* no available registers */ 99 } 100 101 void 102 dt_regset_free(dt_regset_t *drp, int reg) 103 { 104 assert(reg > 0 && reg < drp->dr_size); 105 assert(BT_TEST(drp->dr_bitmap, reg) != 0); 106 BT_CLEAR(drp->dr_bitmap, reg); 107 } 108