vga_post.c revision 1.4 
1/* $OpenBSD: vga_post.c,v 1.4 2009/06/14 20:27:24 miod Exp $ */
2/* $NetBSD: vga_post.c,v 1.12 2009/03/15 21:32:36 cegger Exp $ */
3
4/*-
5 * Copyright (c) 2007 Joerg Sonnenberger <joerg@NetBSD.org>.
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 *
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in
16 *    the documentation and/or other materials provided with the
17 *    distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
21 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
22 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
23 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
24 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
25 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
26 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
27 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
28 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
29 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33#include <sys/cdefs.h>
34
35#include <sys/param.h>
36#include <sys/device.h>
37#include <sys/malloc.h>
38#include <uvm/uvm_extern.h>
39#include <uvm/uvm_page.h>
40
41#include <machine/pio.h>
42
43#include <machine/vga_post.h>
44
45#include <dev/x86emu/x86emu.h>
46#include <dev/x86emu/x86emu_regs.h>
47
48#define	BASE_MEMORY	65536	/* How much memory to allocate in Real Mode */
49
50struct vga_post {
51	struct x86emu emu;
52	vaddr_t sys_image;
53	uint32_t initial_eax;
54	uint8_t bios_data[PAGE_SIZE];
55	struct pglist ram_backing;
56};
57
58#ifdef DDB
59static struct vga_post *ddb_vgapostp;
60void ddb_vgapost(void);
61#endif
62
63static uint8_t
64vm86_emu_inb(struct x86emu *emu, uint16_t port)
65{
66	if (port == 0xb2) /* APM scratch register */
67		return 0;
68
69	if (port >= 0x80 && port < 0x88) /* POST status register */
70		return 0;
71
72	return inb(port);
73}
74
75static uint16_t
76vm86_emu_inw(struct x86emu *emu, uint16_t port)
77{
78	if (port >= 0x80 && port < 0x88) /* POST status register */
79		return 0;
80
81	return inw(port);
82}
83
84static uint32_t
85vm86_emu_inl(struct x86emu *emu, uint16_t port)
86{
87	if (port >= 0x80 && port < 0x88) /* POST status register */
88		return 0;
89
90	return inl(port);
91}
92
93static void
94vm86_emu_outb(struct x86emu *emu, uint16_t port, uint8_t val)
95{
96	if (port == 0xb2) /* APM scratch register */
97		return;
98
99	if (port >= 0x80 && port < 0x88) /* POST status register */
100		return;
101
102	outb(port, val);
103}
104
105static void
106vm86_emu_outw(struct x86emu *emu, uint16_t port, uint16_t val)
107{
108	if (port >= 0x80 && port < 0x88) /* POST status register */
109		return;
110
111	outw(port, val);
112}
113
114static void
115vm86_emu_outl(struct x86emu *emu, uint16_t port, uint32_t val)
116{
117	if (port >= 0x80 && port < 0x88) /* POST status register */
118		return;
119
120	outl(port, val);
121}
122
123struct vga_post *
124vga_post_init(int bus, int device, int function)
125{
126	struct vga_post *sc;
127	vaddr_t iter;
128	struct vm_page *pg;
129	vaddr_t sys_image, sys_bios_data;
130	int err;
131
132	sys_bios_data = uvm_km_valloc(kernel_map, PAGE_SIZE);
133	if (sys_bios_data == 0)
134		return NULL;
135
136	sys_image = uvm_km_valloc(kernel_map, 1024 * 1024);
137	if (sys_image == 0) {
138		uvm_km_free(kernel_map, sys_bios_data, PAGE_SIZE);
139		return NULL;
140	}
141	sc = malloc(sizeof(*sc), M_DEVBUF, M_WAITOK|M_ZERO);
142
143	TAILQ_INIT(&sc->ram_backing);
144	err = uvm_pglistalloc(BASE_MEMORY, 0, (paddr_t)-1, 0, 0,
145	    &sc->ram_backing, BASE_MEMORY/PAGE_SIZE, UVM_PLA_WAITOK);
146	if (err) {
147		uvm_km_free(kernel_map, sc->sys_image, 1024 * 1024);
148		free(sc, M_DEVBUF);
149		return NULL;
150	}
151
152	sc->sys_image = sys_image;
153	sc->emu.sys_private = sc;
154
155	pmap_kenter_pa(sys_bios_data, 0, VM_PROT_READ);
156	pmap_update(pmap_kernel());
157	memcpy((void *)sc->bios_data, (void *)sys_bios_data, PAGE_SIZE);
158	pmap_kremove(sys_bios_data, PAGE_SIZE);
159	uvm_km_free(kernel_map, sys_bios_data, PAGE_SIZE);
160
161	iter = 0;
162	TAILQ_FOREACH(pg, &sc->ram_backing, pageq) {
163		pmap_kenter_pa(sc->sys_image + iter, VM_PAGE_TO_PHYS(pg),
164				VM_PROT_READ | VM_PROT_WRITE);
165		iter += PAGE_SIZE;
166	}
167	KASSERT(iter == BASE_MEMORY);
168
169	for (iter = 640 * 1024; iter < 1024 * 1024; iter += PAGE_SIZE)
170		pmap_kenter_pa(sc->sys_image + iter, iter,
171				VM_PROT_READ | VM_PROT_WRITE);
172	pmap_update(pmap_kernel());
173
174	memset(&sc->emu, 0, sizeof(sc->emu));
175	x86emu_init_default(&sc->emu);
176	sc->emu.emu_inb = vm86_emu_inb;
177	sc->emu.emu_inw = vm86_emu_inw;
178	sc->emu.emu_inl = vm86_emu_inl;
179	sc->emu.emu_outb = vm86_emu_outb;
180	sc->emu.emu_outw = vm86_emu_outw;
181	sc->emu.emu_outl = vm86_emu_outl;
182
183	sc->emu.mem_base = (char *)sc->sys_image;
184	sc->emu.mem_size = 1024 * 1024;
185
186	sc->initial_eax = bus * 256 + device * 8 + function;
187#ifdef DDB
188	ddb_vgapostp = sc;
189#endif
190	return sc;
191}
192
193void
194vga_post_call(struct vga_post *sc)
195{
196	sc->emu.x86.R_EAX = sc->initial_eax;
197	sc->emu.x86.R_EDX = 0x00000080;
198	sc->emu.x86.R_DS = 0x0040;
199	sc->emu.x86.register_flags = 0x3200;
200
201	memcpy((void *)sc->sys_image, sc->bios_data, PAGE_SIZE);
202
203	/* stack is at the end of the first 64KB */
204	sc->emu.x86.R_SS = 0;
205	sc->emu.x86.R_ESP = 0;
206
207	/* Jump straight into the VGA BIOS POST code */
208	x86emu_exec_call(&sc->emu, 0xc000, 0x0003);
209}
210
211void
212vga_post_free(struct vga_post *sc)
213{
214	uvm_pglistfree(&sc->ram_backing);
215	pmap_kremove(sc->sys_image, 1024 * 1024);
216	uvm_km_free(kernel_map, sc->sys_image, 1024 * 1024);
217	pmap_update(pmap_kernel());
218	free(sc, M_DEVBUF);
219}
220
221#ifdef DDB
222void
223ddb_vgapost(void)
224{
225
226	if (ddb_vgapostp)
227		vga_post_call(ddb_vgapostp);
228	else
229		printf("ddb_vgapost: vga_post not initialized\n");
230}
231#endif
232