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-rw-r--r--drivers/char/Makefile1
-rw-r--r--drivers/char/hvc_lguest.c177
2 files changed, 0 insertions, 178 deletions
diff --git a/drivers/char/Makefile b/drivers/char/Makefile
index 057c8bbd7723..07304d50e0cb 100644
--- a/drivers/char/Makefile
+++ b/drivers/char/Makefile
@@ -42,7 +42,6 @@ obj-$(CONFIG_SYNCLINK_GT) += synclink_gt.o
42obj-$(CONFIG_N_HDLC) += n_hdlc.o 42obj-$(CONFIG_N_HDLC) += n_hdlc.o
43obj-$(CONFIG_AMIGA_BUILTIN_SERIAL) += amiserial.o 43obj-$(CONFIG_AMIGA_BUILTIN_SERIAL) += amiserial.o
44obj-$(CONFIG_SX) += sx.o generic_serial.o 44obj-$(CONFIG_SX) += sx.o generic_serial.o
45obj-$(CONFIG_LGUEST_GUEST) += hvc_lguest.o
46obj-$(CONFIG_RIO) += rio/ generic_serial.o 45obj-$(CONFIG_RIO) += rio/ generic_serial.o
47obj-$(CONFIG_HVC_CONSOLE) += hvc_vio.o hvsi.o 46obj-$(CONFIG_HVC_CONSOLE) += hvc_vio.o hvsi.o
48obj-$(CONFIG_HVC_ISERIES) += hvc_iseries.o 47obj-$(CONFIG_HVC_ISERIES) += hvc_iseries.o
diff --git a/drivers/char/hvc_lguest.c b/drivers/char/hvc_lguest.c
deleted file mode 100644
index efccb2155830..000000000000
--- a/drivers/char/hvc_lguest.c
+++ /dev/null
@@ -1,177 +0,0 @@
1/*D:300
2 * The Guest console driver
3 *
4 * This is a trivial console driver: we use lguest's DMA mechanism to send
5 * bytes out, and register a DMA buffer to receive bytes in. It is assumed to
6 * be present and available from the very beginning of boot.
7 *
8 * Writing console drivers is one of the few remaining Dark Arts in Linux.
9 * Fortunately for us, the path of virtual consoles has been well-trodden by
10 * the PowerPC folks, who wrote "hvc_console.c" to generically support any
11 * virtual console. We use that infrastructure which only requires us to write
12 * the basic put_chars and get_chars functions and call the right register
13 * functions.
14 :*/
15
16/*M:002 The console can be flooded: while the Guest is processing input the
17 * Host can send more. Buffering in the Host could alleviate this, but it is a
18 * difficult problem in general. :*/
19/* Copyright (C) 2006 Rusty Russell, IBM Corporation
20 *
21 * This program is free software; you can redistribute it and/or modify
22 * it under the terms of the GNU General Public License as published by
23 * the Free Software Foundation; either version 2 of the License, or
24 * (at your option) any later version.
25 *
26 * This program is distributed in the hope that it will be useful,
27 * but WITHOUT ANY WARRANTY; without even the implied warranty of
28 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
29 * GNU General Public License for more details.
30 *
31 * You should have received a copy of the GNU General Public License
32 * along with this program; if not, write to the Free Software
33 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
34 */
35#include <linux/err.h>
36#include <linux/init.h>
37#include <linux/lguest_bus.h>
38#include <asm/paravirt.h>
39#include "hvc_console.h"
40
41/*D:340 This is our single console input buffer, with associated "struct
42 * lguest_dma" referring to it. Note the 0-terminated length array, and the
43 * use of physical address for the buffer itself. */
44static char inbuf[256];
45static struct lguest_dma cons_input = { .used_len = 0,
46 .addr[0] = __pa(inbuf),
47 .len[0] = sizeof(inbuf),
48 .len[1] = 0 };
49
50/*D:310 The put_chars() callback is pretty straightforward.
51 *
52 * First we put the pointer and length in a "struct lguest_dma": we only have
53 * one pointer, so we set the second length to 0. Then we use SEND_DMA to send
54 * the data to (Host) buffers attached to the console key. Usually a device's
55 * key is a physical address within the device's memory, but because the
56 * console device doesn't have any associated physical memory, we use the
57 * LGUEST_CONSOLE_DMA_KEY constant (aka 0). */
58static int put_chars(u32 vtermno, const char *buf, int count)
59{
60 struct lguest_dma dma;
61
62 /* FIXME: DMA buffers in a "struct lguest_dma" are not allowed
63 * to go over page boundaries. This never seems to happen,
64 * but if it did we'd need to fix this code. */
65 dma.len[0] = count;
66 dma.len[1] = 0;
67 dma.addr[0] = __pa(buf);
68
69 lguest_send_dma(LGUEST_CONSOLE_DMA_KEY, &dma);
70 /* We're expected to return the amount of data we wrote: all of it. */
71 return count;
72}
73
74/*D:350 get_chars() is the callback from the hvc_console infrastructure when
75 * an interrupt is received.
76 *
77 * Firstly we see if our buffer has been filled: if not, we return. The rest
78 * of the code deals with the fact that the hvc_console() infrastructure only
79 * asks us for 16 bytes at a time. We keep a "cons_offset" variable for
80 * partially-read buffers. */
81static int get_chars(u32 vtermno, char *buf, int count)
82{
83 static int cons_offset;
84
85 /* Nothing left to see here... */
86 if (!cons_input.used_len)
87 return 0;
88
89 /* You want more than we have to give? Well, try wanting less! */
90 if (cons_input.used_len - cons_offset < count)
91 count = cons_input.used_len - cons_offset;
92
93 /* Copy across to their buffer and increment offset. */
94 memcpy(buf, inbuf + cons_offset, count);
95 cons_offset += count;
96
97 /* Finished? Zero offset, and reset cons_input so Host will use it
98 * again. */
99 if (cons_offset == cons_input.used_len) {
100 cons_offset = 0;
101 cons_input.used_len = 0;
102 }
103 return count;
104}
105/*:*/
106
107static struct hv_ops lguest_cons = {
108 .get_chars = get_chars,
109 .put_chars = put_chars,
110};
111
112/*D:320 Console drivers are initialized very early so boot messages can go
113 * out. At this stage, the console is output-only. Our driver checks we're a
114 * Guest, and if so hands hvc_instantiate() the console number (0), priority
115 * (0), and the struct hv_ops containing the put_chars() function. */
116static int __init cons_init(void)
117{
118 if (strcmp(pv_info.name, "lguest") != 0)
119 return 0;
120
121 return hvc_instantiate(0, 0, &lguest_cons);
122}
123console_initcall(cons_init);
124
125/*D:370 To set up and manage our virtual console, we call hvc_alloc() and
126 * stash the result in the private pointer of the "struct lguest_device".
127 * Since we never remove the console device we never need this pointer again,
128 * but using ->private is considered good form, and you never know who's going
129 * to copy your driver.
130 *
131 * Once the console is set up, we bind our input buffer ready for input. */
132static int lguestcons_probe(struct lguest_device *lgdev)
133{
134 int err;
135
136 /* The first argument of hvc_alloc() is the virtual console number, so
137 * we use zero. The second argument is the interrupt number.
138 *
139 * The third argument is a "struct hv_ops" containing the put_chars()
140 * and get_chars() pointers. The final argument is the output buffer
141 * size: we use 256 and expect the Host to have room for us to send
142 * that much. */
143 lgdev->private = hvc_alloc(0, lgdev_irq(lgdev), &lguest_cons, 256);
144 if (IS_ERR(lgdev->private))
145 return PTR_ERR(lgdev->private);
146
147 /* We bind a single DMA buffer at key LGUEST_CONSOLE_DMA_KEY.
148 * "cons_input" is that statically-initialized global DMA buffer we saw
149 * above, and we also give the interrupt we want. */
150 err = lguest_bind_dma(LGUEST_CONSOLE_DMA_KEY, &cons_input, 1,
151 lgdev_irq(lgdev));
152 if (err)
153 printk("lguest console: failed to bind buffer.\n");
154 return err;
155}
156/* Note the use of lgdev_irq() for the interrupt number. We tell hvc_alloc()
157 * to expect input when this interrupt is triggered, and then tell
158 * lguest_bind_dma() that is the interrupt to send us when input comes in. */
159
160/*D:360 From now on the console driver follows standard Guest driver form:
161 * register_lguest_driver() registers the device type and probe function, and
162 * the probe function sets up the device.
163 *
164 * The standard "struct lguest_driver": */
165static struct lguest_driver lguestcons_drv = {
166 .name = "lguestcons",
167 .owner = THIS_MODULE,
168 .device_type = LGUEST_DEVICE_T_CONSOLE,
169 .probe = lguestcons_probe,
170};
171
172/* The standard init function */
173static int __init hvc_lguest_init(void)
174{
175 return register_lguest_driver(&lguestcons_drv);
176}
177module_init(hvc_lguest_init);
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