xref: /netbsd-src/sys/arch/aarch64/aarch64/efi_machdep.c (revision 33881f779a77dce6440bdc44610d94de75bebefe)
1 /* $NetBSD: efi_machdep.c,v 1.5 2019/12/16 00:03:50 jmcneill 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>.
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 1.5 2019/12/16 00:03:50 jmcneill Exp $");
34 
35 #include <sys/param.h>
36 #include <uvm/uvm_extern.h>
37 #include <machine/cpufunc.h>
38 
39 #include <arm/arm/efi_runtime.h>
40 
41 #include <aarch64/machdep.h>
42 
43 static struct {
44 	struct faultbuf	faultbuf;
45 	bool		fpu_used;
46 } arm_efirt_state;
47 
48 void
49 arm_efirt_md_map_range(vaddr_t va, paddr_t pa, size_t sz, enum arm_efirt_mem_type type)
50 {
51 	pt_entry_t attr;
52 
53 	switch (type) {
54 	case ARM_EFIRT_MEM_CODE:
55 		attr = LX_BLKPAG_OS_READ | LX_BLKPAG_OS_WRITE |
56 		       LX_BLKPAG_AF | LX_BLKPAG_AP_RW | LX_BLKPAG_UXN |
57 		       LX_BLKPAG_ATTR_NORMAL_WB;
58 		break;
59 	case ARM_EFIRT_MEM_DATA:
60 		attr = LX_BLKPAG_OS_READ | LX_BLKPAG_OS_WRITE |
61 		       LX_BLKPAG_AF | LX_BLKPAG_AP_RW | LX_BLKPAG_UXN | LX_BLKPAG_PXN |
62 		       LX_BLKPAG_ATTR_NORMAL_WB;
63 		break;
64 	case ARM_EFIRT_MEM_MMIO:
65 		attr = LX_BLKPAG_OS_READ | LX_BLKPAG_OS_WRITE |
66 		       LX_BLKPAG_AF | LX_BLKPAG_AP_RW | LX_BLKPAG_UXN | LX_BLKPAG_PXN |
67 		       LX_BLKPAG_ATTR_DEVICE_MEM;
68 		break;
69 	default:
70 		panic("arm_efirt_md_map_range: unsupported type %d", type);
71 	}
72 
73 	pmapboot_enter(va, pa, sz, L3_SIZE, attr, 0, bootpage_alloc, NULL);
74 	while (sz >= PAGE_SIZE) {
75 		aarch64_tlbi_by_va(va);
76 		va += PAGE_SIZE;
77 		sz -= PAGE_SIZE;
78 	}
79 }
80 
81 int
82 arm_efirt_md_enter(void)
83 {
84 	struct lwp *l = curlwp;
85 
86 	/* Save FPU state */
87 	arm_efirt_state.fpu_used = fpu_used_p(l) != 0;
88 	if (arm_efirt_state.fpu_used)
89 		fpu_save(l);
90 
91 	/* Enable FP access (AArch64 UEFI calling convention) */
92 	reg_cpacr_el1_write(CPACR_FPEN_ALL);
93 	__asm __volatile ("isb");
94 
95 	/*
96 	 * Install custom fault handler. EFI lock is held across calls so
97 	 * shared faultbuf is safe here.
98 	 */
99 	return cpu_set_onfault(&arm_efirt_state.faultbuf);
100 }
101 
102 void
103 arm_efirt_md_exit(void)
104 {
105 	struct lwp *l = curlwp;
106 
107 	/* Disable FP access */
108 	reg_cpacr_el1_write(CPACR_FPEN_NONE);
109 	__asm __volatile ("isb");
110 
111 	/* Restore FPU state */
112 	if (arm_efirt_state.fpu_used)
113 		fpu_load(l);
114 
115 	/* Remove custom fault handler */
116 	cpu_unset_onfault();
117 }
118