xref: /netbsd-src/sys/arch/arm/arm/efi_machdep.c (revision 9b383adc631534b9ef7e503863f9e314ac60e151)
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@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
arm_efirt_md_enter(void)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
arm_efirt_md_exit(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
cpu_efirt_map_range(vaddr_t va,paddr_t pa,size_t sz,enum cpu_efirt_mem_type type)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