1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 
3 /*
4  * IBM ASM Service Processor Device Driver
5  *
6  * Copyright (C) IBM Corporation, 2004
7  *
8  * Author: Max Asböck <amax@us.ibm.com>
9  */
10 
11 #include <linux/kernel.h>
12 #include <linux/types.h>
13 #include <linux/errno.h>
14 #include <linux/list.h>
15 #include <linux/wait.h>
16 #include <linux/spinlock.h>
17 #include <linux/slab.h>
18 #include <linux/module.h>
19 #include <linux/interrupt.h>
20 #include <linux/kref.h>
21 #include <linux/device.h>
22 #include <linux/input.h>
23 #include <linux/time64.h>
24 
25 /* Driver identification */
26 #define DRIVER_NAME	"ibmasm"
27 #define DRIVER_VERSION  "1.0"
28 #define DRIVER_AUTHOR   "Max Asbock <masbock@us.ibm.com>, Vernon Mauery <vernux@us.ibm.com>"
29 #define DRIVER_DESC     "IBM ASM Service Processor Driver"
30 
31 #define err(msg) printk(KERN_ERR "%s: " msg "\n", DRIVER_NAME)
32 #define info(msg) printk(KERN_INFO "%s: " msg "\n", DRIVER_NAME)
33 
34 extern int ibmasm_debug;
35 #define dbg(STR, ARGS...)					\
36 	do {							\
37 		if (ibmasm_debug)				\
38 			printk(KERN_DEBUG STR , ##ARGS);	\
39 	} while (0)
40 
get_timestamp(char * buf)41 static inline char *get_timestamp(char *buf)
42 {
43 	struct timespec64 now;
44 
45 	ktime_get_real_ts64(&now);
46 	sprintf(buf, "%llu.%.08lu", (long long)now.tv_sec,
47 				now.tv_nsec / NSEC_PER_USEC);
48 	return buf;
49 }
50 
51 #define IBMASM_CMD_PENDING	0
52 #define IBMASM_CMD_COMPLETE	1
53 #define IBMASM_CMD_FAILED	2
54 
55 #define IBMASM_CMD_TIMEOUT_NORMAL	45
56 #define IBMASM_CMD_TIMEOUT_EXTRA	240
57 
58 #define IBMASM_CMD_MAX_BUFFER_SIZE	0x8000
59 
60 #define REVERSE_HEARTBEAT_TIMEOUT	120
61 
62 #define HEARTBEAT_BUFFER_SIZE		0x400
63 
64 #ifdef IA64
65 #define IBMASM_DRIVER_VPD "Lin64 6.08      "
66 #else
67 #define IBMASM_DRIVER_VPD "Lin32 6.08      "
68 #endif
69 
70 #define SYSTEM_STATE_OS_UP      5
71 #define SYSTEM_STATE_OS_DOWN    4
72 
73 #define IBMASM_NAME_SIZE	16
74 
75 #define IBMASM_NUM_EVENTS	10
76 #define IBMASM_EVENT_MAX_SIZE	2048u
77 
78 
79 struct command {
80 	struct list_head	queue_node;
81 	wait_queue_head_t	wait;
82 	unsigned char		*buffer;
83 	size_t			buffer_size;
84 	int			status;
85 	struct kref		kref;
86 	spinlock_t		*lock;
87 };
88 #define to_command(c) container_of(c, struct command, kref)
89 
90 void ibmasm_free_command(struct kref *kref);
command_put(struct command * cmd)91 static inline void command_put(struct command *cmd)
92 {
93 	unsigned long flags;
94 	spinlock_t *lock = cmd->lock;
95 
96 	spin_lock_irqsave(lock, flags);
97 	kref_put(&cmd->kref, ibmasm_free_command);
98 	spin_unlock_irqrestore(lock, flags);
99 }
100 
command_get(struct command * cmd)101 static inline void command_get(struct command *cmd)
102 {
103 	kref_get(&cmd->kref);
104 }
105 
106 
107 struct ibmasm_event {
108 	unsigned int	serial_number;
109 	unsigned int	data_size;
110 	unsigned char	data[IBMASM_EVENT_MAX_SIZE];
111 };
112 
113 struct event_buffer {
114 	struct ibmasm_event	events[IBMASM_NUM_EVENTS];
115 	unsigned int		next_serial_number;
116 	unsigned int		next_index;
117 	struct list_head	readers;
118 };
119 
120 struct event_reader {
121 	int			cancelled;
122 	unsigned int		next_serial_number;
123 	wait_queue_head_t	wait;
124 	struct list_head	node;
125 	unsigned int		data_size;
126 	unsigned char		data[IBMASM_EVENT_MAX_SIZE];
127 };
128 
129 struct reverse_heartbeat {
130 	wait_queue_head_t	wait;
131 	unsigned int		stopped;
132 };
133 
134 struct ibmasm_remote {
135 	struct input_dev *keybd_dev;
136 	struct input_dev *mouse_dev;
137 };
138 
139 struct service_processor {
140 	struct list_head	node;
141 	spinlock_t		lock;
142 	void __iomem		*base_address;
143 	unsigned int		irq;
144 	struct command		*current_command;
145 	struct command		*heartbeat;
146 	struct list_head	command_queue;
147 	struct event_buffer	*event_buffer;
148 	char			dirname[IBMASM_NAME_SIZE];
149 	char			devname[IBMASM_NAME_SIZE];
150 	unsigned int		number;
151 	struct ibmasm_remote	remote;
152 	int			serial_line;
153 	struct device		*dev;
154 };
155 
156 /* command processing */
157 struct command *ibmasm_new_command(struct service_processor *sp, size_t buffer_size);
158 void ibmasm_exec_command(struct service_processor *sp, struct command *cmd);
159 void ibmasm_wait_for_response(struct command *cmd, int timeout);
160 void ibmasm_receive_command_response(struct service_processor *sp, void *response,  size_t size);
161 
162 /* event processing */
163 int ibmasm_event_buffer_init(struct service_processor *sp);
164 void ibmasm_event_buffer_exit(struct service_processor *sp);
165 void ibmasm_receive_event(struct service_processor *sp, void *data,  unsigned int data_size);
166 void ibmasm_event_reader_register(struct service_processor *sp, struct event_reader *reader);
167 void ibmasm_event_reader_unregister(struct service_processor *sp, struct event_reader *reader);
168 int ibmasm_get_next_event(struct service_processor *sp, struct event_reader *reader);
169 void ibmasm_cancel_next_event(struct event_reader *reader);
170 
171 /* heartbeat - from SP to OS */
172 void ibmasm_register_panic_notifier(void);
173 void ibmasm_unregister_panic_notifier(void);
174 int ibmasm_heartbeat_init(struct service_processor *sp);
175 void ibmasm_heartbeat_exit(struct service_processor *sp);
176 void ibmasm_receive_heartbeat(struct service_processor *sp,  void *message, size_t size);
177 
178 /* reverse heartbeat - from OS to SP */
179 void ibmasm_init_reverse_heartbeat(struct service_processor *sp, struct reverse_heartbeat *rhb);
180 int ibmasm_start_reverse_heartbeat(struct service_processor *sp, struct reverse_heartbeat *rhb);
181 void ibmasm_stop_reverse_heartbeat(struct reverse_heartbeat *rhb);
182 
183 /* dot commands */
184 void ibmasm_receive_message(struct service_processor *sp, void *data, int data_size);
185 int ibmasm_send_driver_vpd(struct service_processor *sp);
186 int ibmasm_send_os_state(struct service_processor *sp, int os_state);
187 
188 /* low level message processing */
189 int ibmasm_send_i2o_message(struct service_processor *sp);
190 irqreturn_t ibmasm_interrupt_handler(int irq, void * dev_id);
191 
192 /* remote console */
193 void ibmasm_handle_mouse_interrupt(struct service_processor *sp);
194 int ibmasm_init_remote_input_dev(struct service_processor *sp);
195 void ibmasm_free_remote_input_dev(struct service_processor *sp);
196 
197 /* file system */
198 int ibmasmfs_register(void);
199 void ibmasmfs_unregister(void);
200 void ibmasmfs_add_sp(struct service_processor *sp);
201 
202 /* uart */
203 #if IS_ENABLED(CONFIG_SERIAL_8250)
204 void ibmasm_register_uart(struct service_processor *sp);
205 void ibmasm_unregister_uart(struct service_processor *sp);
206 #else
207 #define ibmasm_register_uart(sp)	do { } while(0)
208 #define ibmasm_unregister_uart(sp)	do { } while(0)
209 #endif
210