xref: /netbsd-src/sys/stand/efiboot/bootaa64/efibootaa64.c (revision e76fd3da127111b404709dc66115690f7ef5c6e1)
1 /*	$NetBSD: efibootaa64.c,v 1.7 2024/08/15 06:15:17 skrll Exp $	*/
2 
3 /*-
4  * Copyright (c) 2016 Kimihiro Nonaka <nonaka@netbsd.org>
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 REGENTS AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, 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 "../efiboot.h"
30 #include "../efifdt.h"
31 
32 #include <sys/cdefs.h>
33 #include <sys/bootblock.h>
34 
35 #include <loadfile.h>
36 
37 /* cache.S */
38 void aarch64_dcache_wbinv_range(vaddr_t, vsize_t);
39 void aarch64_icache_inv_all(void);
40 void aarch64_exec_kernel(paddr_t, paddr_t);
41 
42 void
43 efi_dcache_flush(u_long start, u_long size)
44 {
45 	aarch64_dcache_wbinv_range(start, size);
46 }
47 
48 void
49 efi_boot_kernel(u_long marks[MARK_MAX])
50 {
51 	u_long kernel_start, kernel_size, kernel_entry;
52 	u_long fdt_start, fdt_size;
53 
54 	kernel_start = marks[MARK_START];
55 	kernel_size = marks[MARK_END] - kernel_start;
56 	kernel_entry = marks[MARK_ENTRY];
57 	fdt_start = (u_long)efi_fdt_data();
58 	fdt_size = efi_fdt_size();
59 
60 	aarch64_dcache_wbinv_range(kernel_start, kernel_size);
61 	if (efi_fdt_size() > 0) {
62 		aarch64_dcache_wbinv_range(fdt_start, fdt_size);
63 	}
64 	aarch64_icache_inv_all();
65 
66 	aarch64_exec_kernel((paddr_t)kernel_entry, (paddr_t)fdt_start);
67 }
68 
69 /*
70  * Returns the current exception level.
71  */
72 static u_int
73 efi_aarch64_current_el(void)
74 {
75 	uint64_t el;
76 	__asm __volatile ("mrs %0, CurrentEL" : "=r" (el));
77 	return (el >> 2) & 0x3;
78 }
79 
80 static bool
81 efi_aarch64_BigEnd(void)
82 {
83 	uint64_t id_aa64mmfr0_el1;
84 	__asm __volatile ("mrs %[mmfr0], id_aa64mmfr0_el1"
85             : [mmfr0] "=r" (id_aa64mmfr0_el1) :: "memory");
86 	return __SHIFTOUT(id_aa64mmfr0_el1, __BITS(11, 8)) == 1;
87 }
88 
89 void
90 efi_md_show(void)
91 {
92 	command_printtab("CurrentEL", "EL%u\n", efi_aarch64_current_el());
93 }
94 
95 int
96 efi_md_prepare_boot(const char *fname, const char *args, u_long *marks)
97 {
98 	if (netbsd_elf_data == ELFDATA2MSB) {
99 		if (!efi_aarch64_BigEnd()) {
100 			printf("Processor does not support big endian at EL1\n");
101 			return ENOTSUP;
102 		}
103 	}
104 	return 0;
105 }
106