udbg_adb.c

  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
 30static void (*udbg_adb_old_putc)(char c);
 31static int (*udbg_adb_old_getc)(void);
 32static int (*udbg_adb_old_getc_poll)(void);
 33
 34static enum {
 35	input_adb_none,
 36	input_adb_pmu,
 37	input_adb_cuda,
 38} input_type = input_adb_none;
 39
 40int xmon_wants_key, xmon_adb_keycode;
 41
 42static 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
 56static int udbg_adb_use_btext;
 57static int xmon_adb_shiftstate;
 58
 59static 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
 67static 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
 75static 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
118static 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 */
134static 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
143static 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
153void __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
163int __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}