xref: /netbsd-src/sys/arch/riscv/riscv/mainbus.c (revision 0ad349337a874f932507463a034e8710784222b7)
1 /*	$NetBSD: mainbus.c,v 1.7 2024/08/04 08:16:25 skrll Exp $	*/
2 
3 /*-
4  * Copyright (c) 2022 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by 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 "opt_console.h"
33 #include "opt_efi.h"
34 #include "opt_modular.h"
35 
36 #include <sys/cdefs.h>
37 
38 __RCSID("$NetBSD: mainbus.c,v 1.7 2024/08/04 08:16:25 skrll Exp $");
39 
40 #include <sys/param.h>
41 #include <sys/types.h>
42 
43 #include <sys/bus.h>
44 #include <sys/device.h>
45 #include <sys/systm.h>
46 
47 #include <uvm/uvm_extern.h>
48 
49 #include <dev/fdt/fdtvar.h>
50 
51 #ifdef CONSADDR
52 #include <dev/ic/comreg.h>
53 #include <dev/ic/comvar.h>
54 #endif
55 
56 #include <machine/sysreg.h>
57 
58 extern struct bus_space riscv_generic_bs_tag;
59 
60 bus_space_tag_t
61 fdtbus_bus_tag_create(int phandle, uint32_t flags)
62 {
63 	return &riscv_generic_bs_tag;
64 }
65 
66 static inline bool
67 cpu_earlydevice_va_p(void)
68 {
69 
70 	return __SHIFTOUT(csr_satp_read(), SATP_MODE);
71 }
72 
73 void com_platform_early_putchar(char);
74 
75 void __noasan
76 com_platform_early_putchar(char c)
77 {
78 #ifdef CONSADDR
79 #define CONSADDR_VA	(VM_KERNEL_IO_BASE + (CONSADDR & SEGOFSET))
80 
81 	volatile uint8_t *uartaddr = cpu_earlydevice_va_p() ?
82 	    (volatile uint8_t *)CONSADDR_VA :
83 	    (volatile uint8_t *)CONSADDR;
84 
85 	while ((uartaddr[com_lsr] & LSR_TXRDY) == 0)
86 		;
87 
88 	uartaddr[com_data] = c;
89 #endif
90 }
91 
92 static int
93 mainbus_match(device_t parent, cfdata_t cf, void *aux)
94 {
95 	static int once = 0;
96 
97 	if (once != 0)
98 		return 0;
99 	once = 1;
100 
101 	return 1;
102 }
103 
104 
105 static void
106 mainbus_attach_devicetree(device_t self)
107 {
108 	struct fdt_attach_args faa = {
109 		.faa_name = "",
110 		.faa_phandle = OF_peer(0),
111 		.faa_bst = &riscv_generic_bs_tag,
112 	};
113 
114 	aprint_normal("\n");
115 
116 	config_found(self, &faa, NULL, CFARGS(.iattr = "fdt"));
117 }
118 
119 static void
120 mainbus_attach(device_t parent, device_t self, void *aux)
121 {
122 	if (fdtbus_get_data() != NULL) {
123 		mainbus_attach_devicetree(self);
124 	}
125 }
126 
127 CFATTACH_DECL_NEW(mainbus, 0, mainbus_match, mainbus_attach, NULL, NULL);
128