1 /* $NetBSD: efi_machdep.c,v 1.4 2023/07/10 07:00:12 rin Exp $ */ 2 3 /*- 4 * Copyright (c) 2018 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Jared McNeill <jmcneill (at) invisible.ca> and Nick Hudson 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 #include <sys/cdefs.h> 33 __KERNEL_RCSID(0, "$NetBSD: efi_machdep.c,v 1.4 2023/07/10 07:00:12 rin Exp $"); 34 35 #include <sys/param.h> 36 37 #include <uvm/uvm_extern.h> 38 39 #include <arm/efirt.h> 40 #include <arm/vfpreg.h> 41 42 #include <arm/arm/efi_runtime.h> 43 44 #include <arm/arm32/machdep.h> 45 46 static struct { 47 struct faultbuf aert_faultbuf; 48 uint32_t aert_tpidrprw; 49 uint32_t aert_fpexc; 50 } arm_efirt_state; 51 52 int 53 arm_efirt_md_enter(void) 54 { 55 kpreempt_disable(); 56 57 struct lwp * const l = curlwp; 58 59 arm_efirt_state.aert_tpidrprw = armreg_tpidrprw_read(); 60 61 /* Disable the VFP. */ 62 arm_efirt_state.aert_fpexc = armreg_fpexc_read(); 63 armreg_fpexc_write(arm_efirt_state.aert_fpexc & ~VFP_FPEXC_EN); 64 isb(); 65 66 /* 67 * Install custom fault handler. EFI lock is held across calls so 68 * shared faultbuf is safe here. 69 */ 70 int err = cpu_set_onfault(&arm_efirt_state.aert_faultbuf); 71 if (err) 72 return err; 73 74 if ((l->l_flag & LW_SYSTEM) == 0) { 75 pmap_deactivate(l); 76 } 77 pmap_activate_efirt(); 78 79 return 0; 80 } 81 82 void 83 arm_efirt_md_exit(void) 84 { 85 struct lwp * const l = curlwp; 86 87 pmap_deactivate_efirt(); 88 if ((l->l_flag & LW_SYSTEM) == 0) { 89 pmap_activate(l); 90 } 91 92 armreg_tpidrprw_write(arm_efirt_state.aert_tpidrprw); 93 94 /* Restore FP access (if it existed) */ 95 armreg_fpexc_write(arm_efirt_state.aert_fpexc); 96 isb(); 97 98 /* Remove custom fault handler */ 99 cpu_unset_onfault(); 100 101 kpreempt_enable(); 102 } 103 104 105 void 106 cpu_efirt_map_range(vaddr_t va, paddr_t pa, size_t sz, 107 enum cpu_efirt_mem_type type) 108 { 109 int flags = 0; 110 int prot = 0; 111 112 switch (type) { 113 case ARM_EFIRT_MEM_CODE: 114 /* need write permission because fw devs */ 115 prot = VM_PROT_READ | VM_PROT_WRITE | VM_PROT_EXECUTE; 116 flags = prot; 117 break; 118 case ARM_EFIRT_MEM_DATA: 119 prot = VM_PROT_READ | VM_PROT_WRITE; 120 flags = prot; 121 break; 122 case ARM_EFIRT_MEM_MMIO: 123 prot = VM_PROT_READ | VM_PROT_WRITE; 124 flags = prot | PMAP_DEV; 125 break; 126 default: 127 panic("%s: unsupported type %d", __func__, type); 128 } 129 if (va >= VM_MAXUSER_ADDRESS || va >= VM_MAXUSER_ADDRESS - sz) { 130 printf("Incorrect EFI mapping range %" PRIxVADDR 131 "- %" PRIxVADDR "\n", va, va + sz); 132 } 133 134 while (sz != 0) { 135 pmap_enter(pmap_efirt(), va, pa, prot, flags | PMAP_WIRED); 136 va += PAGE_SIZE; 137 pa += PAGE_SIZE; 138 sz -= PAGE_SIZE; 139 } 140 pmap_update(pmap_efirt()); 141 } 142