1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/string.h>
3 #include <linux/kernel.h>
4 #include <linux/errno.h>
5 #include <linux/bitops.h>
6 #include <linux/ptrace.h>
7 #include <linux/adb.h>
8 #include <linux/pmu.h>
9 #include <linux/cuda.h>
10 #include <linux/of.h>
11 #include <asm/machdep.h>
12 #include <asm/io.h>
13 #include <asm/page.h>
14 #include <asm/xmon.h>
15 #include <asm/bootx.h>
16 #include <asm/errno.h>
17 #include <asm/pmac_feature.h>
18 #include <asm/processor.h>
19 #include <asm/delay.h>
20 #include <asm/btext.h>
21 #include <asm/time.h>
22 #include <asm/udbg.h>
23 
24 /*
25  * This implementation is "special", it can "patch" the current
26  * udbg implementation and work on top of it. It must thus be
27  * initialized last
28  */
29 
30 static void (*udbg_adb_old_putc)(char c);
31 static int (*udbg_adb_old_getc)(void);
32 static int (*udbg_adb_old_getc_poll)(void);
33 
34 static enum {
35 	input_adb_none,
36 	input_adb_pmu,
37 	input_adb_cuda,
38 } input_type = input_adb_none;
39 
40 int xmon_wants_key, xmon_adb_keycode;
41 
42 static inline void udbg_adb_poll(void)
43 {
44 #ifdef CONFIG_ADB_PMU
45 	if (input_type == input_adb_pmu)
46 		pmu_poll_adb();
47 #endif /* CONFIG_ADB_PMU */
48 #ifdef CONFIG_ADB_CUDA
49 	if (input_type == input_adb_cuda)
50 		cuda_poll();
51 #endif /* CONFIG_ADB_CUDA */
52 }
53 
54 #ifdef CONFIG_BOOTX_TEXT
55 
56 static int udbg_adb_use_btext;
57 static int xmon_adb_shiftstate;
58 
59 static unsigned char xmon_keytab[128] =
60 	"asdfhgzxcv\000bqwer"				/* 0x00 - 0x0f */
61 	"yt123465=97-80]o"				/* 0x10 - 0x1f */
62 	"u[ip\rlj'k;\\,/nm."				/* 0x20 - 0x2f */
63 	"\t `\177\0\033\0\0\0\0\0\0\0\0\0\0"		/* 0x30 - 0x3f */
64 	"\0.\0*\0+\0\0\0\0\0/\r\0-\0"			/* 0x40 - 0x4f */
65 	"\0\0000123456789\0\0\0";			/* 0x50 - 0x5f */
66 
67 static unsigned char xmon_shift_keytab[128] =
68 	"ASDFHGZXCV\000BQWER"				/* 0x00 - 0x0f */
69 	"YT!@#$^%+(&_*)}O"				/* 0x10 - 0x1f */
70 	"U{IP\rLJ\"K:|<?NM>"				/* 0x20 - 0x2f */
71 	"\t ~\177\0\033\0\0\0\0\0\0\0\0\0\0"		/* 0x30 - 0x3f */
72 	"\0.\0*\0+\0\0\0\0\0/\r\0-\0"			/* 0x40 - 0x4f */
73 	"\0\0000123456789\0\0\0";			/* 0x50 - 0x5f */
74 
75 static int udbg_adb_local_getc(void)
76 {
77 	int k, t, on;
78 
79 	xmon_wants_key = 1;
80 	for (;;) {
81 		xmon_adb_keycode = -1;
82 		t = 0;
83 		on = 0;
84 		k = -1;
85 		do {
86 			if (--t < 0) {
87 				on = 1 - on;
88 				btext_drawchar(on? 0xdb: 0x20);
89 				btext_drawchar('\b');
90 				t = 200000;
91 			}
92 			udbg_adb_poll();
93 			if (udbg_adb_old_getc_poll)
94 				k = udbg_adb_old_getc_poll();
95 		} while (k == -1 && xmon_adb_keycode == -1);
96 		if (on)
97 			btext_drawstring(" \b");
98 		if (k != -1)
99 			return k;
100 		k = xmon_adb_keycode;
101 
102 		/* test for shift keys */
103 		if ((k & 0x7f) == 0x38 || (k & 0x7f) == 0x7b) {
104 			xmon_adb_shiftstate = (k & 0x80) == 0;
105 			continue;
106 		}
107 		if (k >= 0x80)
108 			continue;	/* ignore up transitions */
109 		k = (xmon_adb_shiftstate? xmon_shift_keytab: xmon_keytab)[k];
110 		if (k != 0)
111 			break;
112 	}
113 	xmon_wants_key = 0;
114 	return k;
115 }
116 #endif /* CONFIG_BOOTX_TEXT */
117 
118 static int udbg_adb_getc(void)
119 {
120 #ifdef CONFIG_BOOTX_TEXT
121 	if (udbg_adb_use_btext && input_type != input_adb_none)
122 		return udbg_adb_local_getc();
123 #endif
124 	if (udbg_adb_old_getc)
125 		return udbg_adb_old_getc();
126 	return -1;
127 }
128 
129 /* getc_poll() is not really used, unless you have the xmon-over modem
130  * hack that doesn't quite concern us here, thus we just poll the low level
131  * ADB driver to prevent it from timing out and call back the original poll
132  * routine.
133  */
134 static int udbg_adb_getc_poll(void)
135 {
136 	udbg_adb_poll();
137 
138 	if (udbg_adb_old_getc_poll)
139 		return udbg_adb_old_getc_poll();
140 	return -1;
141 }
142 
143 static void udbg_adb_putc(char c)
144 {
145 #ifdef CONFIG_BOOTX_TEXT
146 	if (udbg_adb_use_btext)
147 		btext_drawchar(c);
148 #endif
149 	if (udbg_adb_old_putc)
150 		return udbg_adb_old_putc(c);
151 }
152 
153 void __init udbg_adb_init_early(void)
154 {
155 #ifdef CONFIG_BOOTX_TEXT
156 	if (btext_find_display(1) == 0) {
157 		udbg_adb_use_btext = 1;
158 		udbg_putc = udbg_adb_putc;
159 	}
160 #endif
161 }
162 
163 int __init udbg_adb_init(int force_btext)
164 {
165 	struct device_node *np;
166 
167 	/* Capture existing callbacks */
168 	udbg_adb_old_putc = udbg_putc;
169 	udbg_adb_old_getc = udbg_getc;
170 	udbg_adb_old_getc_poll = udbg_getc_poll;
171 
172 	/* Check if our early init was already called */
173 	if (udbg_adb_old_putc == udbg_adb_putc)
174 		udbg_adb_old_putc = NULL;
175 #ifdef CONFIG_BOOTX_TEXT
176 	if (udbg_adb_old_putc == btext_drawchar)
177 		udbg_adb_old_putc = NULL;
178 #endif
179 
180 	/* Set ours as output */
181 	udbg_putc = udbg_adb_putc;
182 	udbg_getc = udbg_adb_getc;
183 	udbg_getc_poll = udbg_adb_getc_poll;
184 
185 #ifdef CONFIG_BOOTX_TEXT
186 	/* Check if we should use btext output */
187 	if (btext_find_display(force_btext) == 0)
188 		udbg_adb_use_btext = 1;
189 #endif
190 
191 	/* See if there is a keyboard in the device tree with a parent
192 	 * of type "adb". If not, we return a failure, but we keep the
193 	 * bext output set for now
194 	 */
195 	for_each_node_by_name(np, "keyboard") {
196 		struct device_node *parent = of_get_parent(np);
197 		int found = of_node_is_type(parent, "adb");
198 		of_node_put(parent);
199 		if (found)
200 			break;
201 	}
202 	if (np == NULL)
203 		return -ENODEV;
204 	of_node_put(np);
205 
206 #ifdef CONFIG_ADB_PMU
207 	if (find_via_pmu())
208 		input_type = input_adb_pmu;
209 #endif
210 #ifdef CONFIG_ADB_CUDA
211 	if (find_via_cuda())
212 		input_type = input_adb_cuda;
213 #endif
214 
215 	/* Same as above: nothing found, keep btext set for output */
216 	if (input_type == input_adb_none)
217 		return -ENODEV;
218 
219 	return 0;
220 }
221