1 /* $NetBSD: pci_smccc.c,v 1.1 2021/08/07 21:23:37 jmcneill Exp $ */ 2 3 /*- 4 * Copyright (c) 2021 Jared McNeill <jmcneill@invisible.ca> 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 22 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #include <sys/cdefs.h> 30 __KERNEL_RCSID(0, "$NetBSD: pci_smccc.c,v 1.1 2021/08/07 21:23:37 jmcneill Exp $"); 31 32 #include <sys/param.h> 33 #include <sys/kernel.h> 34 35 #include <arm/arm/smccc.h> 36 #include <arm/pci/pci_smccc.h> 37 38 /* Minimum SMCCC version required for PCI_VERSION call. */ 39 #define SMCCC_VERSION_1_1 0x10001 40 41 /* PCI Configuration Space Access ABI functions */ 42 #define PCI_VERSION 0x84000130 43 #define PCI_FEATURES 0x84000131 44 #define PCI_READ 0x84000132 45 #define PCI_WRITE 0x84000133 46 #define PCI_GET_SEG_INFO 0x84000134 47 #define GET_SEG_INFO_BUS_START __BITS(7,0) 48 #define GET_SEG_INFO_BUS_END __BITS(15,8) 49 50 static int 51 pci_smccc_call(uint32_t fid, 52 register_t arg1, register_t arg2, register_t arg3, register_t arg4, 53 register_t *res0, register_t *res1, register_t *res2, register_t *res3) 54 { 55 static int smccc_ver; 56 57 if (smccc_ver == 0) { 58 smccc_ver = smccc_version(); 59 } 60 if (smccc_ver < SMCCC_VERSION_1_1) { 61 return SMCCC_NOT_SUPPORTED; 62 } 63 64 return smccc_call(fid, arg1, arg2, arg3, arg4, 65 res0, res1, res2, res3); 66 } 67 68 int 69 pci_smccc_version(void) 70 { 71 return pci_smccc_call(PCI_VERSION, 0, 0, 0, 0, 72 NULL, NULL, NULL, NULL); 73 } 74 75 int 76 pci_smccc_features(uint32_t fid) 77 { 78 return pci_smccc_call(PCI_FEATURES, fid, 0, 0, 0, 79 NULL, NULL, NULL, NULL); 80 } 81 82 int 83 pci_smccc_read(uint32_t sbdf, uint32_t offset, uint32_t access_size, 84 uint32_t *data) 85 { 86 register_t value; 87 int status; 88 89 status = pci_smccc_call(PCI_READ, sbdf, offset, access_size, 0, 90 NULL, &value, NULL, NULL); 91 if (status == SMCCC_SUCCESS) { 92 *data = value; 93 } 94 95 return status; 96 } 97 98 int 99 pci_smccc_write(uint32_t sbdf, uint32_t offset, uint32_t access_size, 100 uint32_t data) 101 { 102 return pci_smccc_call(PCI_WRITE, sbdf, offset, access_size, data, 103 NULL, NULL, NULL, NULL); 104 } 105 106 int 107 pci_smccc_get_seg_info(uint16_t seg, uint8_t *bus_start, uint8_t *bus_end, 108 uint16_t *next_seg) 109 { 110 register_t res1, res2; 111 int status; 112 113 status = pci_smccc_call(PCI_GET_SEG_INFO, seg, 0, 0, 0, 114 NULL, &res1, &res2, NULL); 115 if (status == SMCCC_SUCCESS) { 116 *bus_start = __SHIFTOUT(res1, GET_SEG_INFO_BUS_START); 117 *bus_end = __SHIFTOUT(res1, GET_SEG_INFO_BUS_END); 118 *next_seg = (uint16_t)res2; 119 } 120 121 return status; 122 } 123