source: trunk/kernel/kern/chdev.h @ 9

Last change on this file since 9 was 5, checked in by alain, 8 years ago

Introduce the chdev_t structure in place of the device_t structure.
File size: 13.7 KB
Line 
1/*
2 * chdev.h - channel device (chdev) descriptor definition.
3 *
4 * Authors  Alain Greiner    (2016)
5 *
6 * Copyright (c) UPMC Sorbonne Universites
7 *
8 * This file is part of ALMOS-MKH
9 *
10 * ALMOS-MKH is free software; you can redistribute it and/or modify it
11 * under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; version 2.0 of the License.
13 *
14 * ALMOS-MKH is distributed in the hope that it will be useful, but
15 * WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17 * General Public License for more details.
18 *
19 * You should have received a copy of the GNU General Public License
20 * along with ALMOS-MKH; if not, write to the Free Software Foundation,
21 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
22 */
23
24#ifndef _CHDEV_H_
25#define _CHDEV_H_
26
27#include <almos_config.h>
28#include <hal_types.h>
29#include <xlist.h>
30#include <metafs.h>
31#include <remote_spinlock.h>
32#include <dev_ioc.h>
33#include <dev_nic.h>
34#include <dev_icu.h>
35#include <dev_pic.h>
36#include <dev_fbf.h>
37
38/******************************************************************************************
39 *       Channel Device descriptor definition
40 *
41 * This file defines the kernel representation of a generic (i.e. implementation
42 * independant) Channel Device descriptor (in brief "chdev").
43 * ALMOS-MKH supports multi-channels peripherals, and defines one separated descriptor
44 * for each channel (and for each RX/TX direction for the NIC device).
45 * Each chdev contains a waiting queue, registering the "client threads" requests,
46 * and an associated "server thread", handling these requests.
47 * These descriptors are physically distributed on all clusters to minimize contention.
48 * Therefore a given I/O operation involve generally three clusters:
49 * - the client cluster, containing the client thread,
50 * - the server cluster, containing the chdev and the client thread,
51 * - the I/O cluster containing the physical device.
52 *****************************************************************************************/
53
54/****  Forward declarations  ****/
55
56struct  chdev_s;
57struct  thread_s;
58struct  boot_info_s;
59
60/******************************************************************************************
61 * These macros extract the functionality and the implementation from the peripheral type.
62 *****************************************************************************************/
63 
64#define FUNC_FROM_TYPE( type )    ((uint32_t)(type>>16))
65#define IMPL_FROM_TYPE( type )    ((uint32_t)(type & 0x0000FFFF))
66
67/******************************************************************************************
68 * This define the generic prototypes for the three functions that must be defined
69 * by all drivers implementing a generic device:
70 * - "init"    : device initialisation.
71 * - "cmd"     : start an I/O operation.
72 * - "isr"     : complete an I/O operation.
73 * The "init" function is called by kernel_init() to initialise the hardware device.
74 * The "cmd" and "isr" are registered in the generic chdev descriptor by kernel_init(),
75 * and are called to start and complete an I/O operation. 
76*****************************************************************************************/
77
78typedef void (dev_ini_t) ( xptr_t dev );     
79typedef void (dev_cmd_t) ( xptr_t thread ); 
80typedef void (dev_isr_t) ( struct chdev_s * dev ); 
81
82/******************************************************************************************
83 * This enum defines the supported generic device types.
84 * These types are functionnal types: all (architecture specific) implementations
85 * provide the same set of operations and the same driver API.
86 * This enum must be consistent with the enum in files arch_info.h, and arch_class.py.
87 *****************************************************************************************/
88 
89enum dev_func_type
90{
91        DEV_FUNC_RAM   =  0,
92        DEV_FUNC_ROM   =  1,
93        DEV_FUNC_FBF   =  2,
94    DEV_FUNC_IOB   =  3,
95    DEV_FUNC_IOC   =  4,
96        DEV_FUNC_MMC   =  5,
97        DEV_FUNC_DMA   =  6,
98        DEV_FUNC_NIC   =  7,
99        DEV_FUNC_TIM   =  8,
100        DEV_FUNC_TXT   =  9,
101    DEV_FUNC_ICU   = 10,
102    DEV_FUNC_PIC   = 11,
103
104    DEV_FUNC_NR    = 12,
105};
106
107/******************************************************************************************
108 * This structure defines a chdev descriptor.
109 * There is one chdev descriptor per channel.
110 * This structure is NOT replicated, and can be located in any cluster.
111 * One kernel thread, in charge of handling the commands registered in the waiting queue
112 * of client threads is associated to each chdev descriptor (not for ICU, PIC, IOB).
113 * For each device type ***, the specific extensions are defined in the "dev_***.h" file.
114 *****************************************************************************************/
115
116typedef struct chdev_s
117{
118        uint32_t             func;        /*! peripheral functionnal type                    */
119        uint32_t             impl;        /*! peripheral inplementation subtype              */
120    uint32_t             channel;     /*! channel index                                  */
121    bool_t               is_rx;       /*! relevant for NIC peripheral channels only      */
122        xptr_t               base;        /*! extended pointer on channel segment            */
123
124    dev_cmd_t          * cmd;         /*! local pointer on driver command function       */
125    dev_isr_t          * isr;         /*! local pointer on driver ISR function           */ 
126    struct thread_s    * server;      /*! local pointer on associated server thread      */
127
128    uint32_t             irq_type;    /*! associated IRQ type in local ICU               */
129    uint32_t             irq_id;      /*! associated IRQ index in local ICU              */
130
131    metafs_t             node;        /*! Metafs node associated with this device        */
132
133        remote_spinlock_t    wait_lock;   /*! lock protecting exclusive access to queue      */
134    xlist_entry_t        wait_root;   /*! root of waiting threads queue                  */
135
136    union
137    {
138        ioc_extend_t     ioc;         /*! IOC specific extension                         */
139        nic_extend_t     nic;         /*! NIC specific extension                         */
140        icu_extend_t     icu;         /*! ICU specific extension                         */
141        pic_extend_t     pic;         /*! PIC specific extension                         */
142        fbf_extend_t     fbf;         /*! FBF specific extension                         */
143    } 
144    ext;
145}
146chdev_t;
147
148/******************************************************************************************
149 * This structure defines the channel_devices descriptors directory.
150 * Each entry in this structure contains an extended pointer on a chdev descriptor.
151 * There is one entry per channel OR per cluster, depending on peripheral type.
152 * This structure is replicated in each cluster, and is initialised during kernel init.
153 * It is used for fast access to a device descriptor, from type and channel for an
154 * external peripheral, or from type and cluster for a hared internal peripheral.
155 * - a "shared" chdev can be accessed by any thread running in any cluster.
156 * - a "private" chdev can only be accessed by a thread running in local cluster.
157 *****************************************************************************************/
158
159typedef struct chdev_directory_s
160{
161    xptr_t   iob;                                // external / single channel / shared
162    xptr_t   pic;                                // external / single channel / shared
163
164    xptr_t   txt[CONFIG_MAX_TXT_CHANNELS];       // external / multi-channels / shared
165    xptr_t   ioc[CONFIG_MAX_IOC_CHANNELS];       // external / multi-channels / shared
166    xptr_t   fbf[CONFIG_MAX_FBF_CHANNELS];       // external / multi-channels / shared
167    xptr_t   nic_rx[CONFIG_MAX_NIC_CHANNELS];    // external / multi-channels / shared
168    xptr_t   nic_tx[CONFIG_MAX_NIC_CHANNELS];    // external / multi-channels / shared
169
170    xptr_t   icu[CONFIG_MAX_CLUSTERS];           // internal / single channel / shared
171    xptr_t   mmc[CONFIG_MAX_CLUSTERS];           // internal / single channel / shared
172
173    xptr_t   dma[CONFIG_MAX_DMA_CHANNELS];       // internal / multi-channels / private
174}
175chdev_directory_t;
176
177/******************************************************************************************
178 * This structure defines the input IRQS for the PIC device, that is used by all external
179 * peripherals (IOC, NIC, TXT, etc.) to signal completion of an I/O operation. It describes
180 * the hardware wiring of IRQs between external peripherals and PIC, as each entry in this
181 * structure contains the input IRQ index in PIC. Value is -1 for an unused input.
182 * For a multi-channels peripheral, there is one chdev and one IRQ per channel.
183 * This structure is replicated in each cluster. It is allocated as a global variable
184 * in the kernel_init.c file, and is initialised during kernel init.
185 *****************************************************************************************/
186
187typedef struct chdev_pic_input_s
188{
189    uint32_t   txt[CONFIG_MAX_TXT_CHANNELS];
190    uint32_t   ioc[CONFIG_MAX_IOC_CHANNELS];
191    uint32_t   nic_rx[CONFIG_MAX_NIC_CHANNELS];
192    uint32_t   nic_tx[CONFIG_MAX_NIC_CHANNELS];
193}
194chdev_pic_input_t;
195
196/******************************************************************************************
197 * This structure defines the input IRQS for the ICU device, that is used by all internal
198 * peripherals IRQS (DMA, MMC, etc.) to signal completion of an I/O operation. It describes
199 * the hardware wiring of IRQs between internal peripherals and ICU, as each entry in this
200 * structure contains the input IRQ index in ICU. Value is -1 for an unused input.
201 * For a multi-channels peripheral, there is one chdev and one IRQ per channel.
202 * This structure is replicated in each cluster. It is allocated as a global variable
203 * in the kernel_init.c file, and is initialised during kernel init.
204 *****************************************************************************************/
205
206typedef struct chdev_icu_input_s
207{
208    uint32_t   dma[CONFIG_MAX_DMA_CHANNELS];
209    uint32_t   mmc;                             // MMC is single channel
210}
211chdev_icu_input_t;
212
213/******************************************************************************************
214 * This function display relevant values for a chdev descriptor.
215 ******************************************************************************************
216 * @ chdev   : pointer on chdev.
217 *****************************************************************************************/
218void chdev_print( chdev_t * chdev );
219
220/******************************************************************************************
221 * This function returns a printable string for a device functionnal types.
222 ******************************************************************************************
223 * @ func_type  : functionnal type.
224 * @ return a printable string.
225 *****************************************************************************************/
226char * chdev_func_str( uint32_t func_type );
227
228/******************************************************************************************
229 * This  function allocates memory and initializes a chdev descriptor in local cluster,
230 * from arguments values.  It should be called by a local thread.
231 * The device specific fields are initialised later.
232 ******************************************************************************************
233 * @ func      : functionnal type.
234 * @ impl      : implementation type.
235 * @ channel   : channel index / for multi-channels peripherals.
236 * @ is_rx     : for NIC peripheral / NIC RX if true / NIC TX if false.
237 * @ base      : extended pointer on peripheral segment base.
238 * @ return a local pointer on created chdev / return NULL if failure.
239 *****************************************************************************************/
240chdev_t * chdev_create( uint32_t    func,
241                        uint32_t    impl,
242                        uint32_t    channel,
243                        bool_t      is_rx,
244                        xptr_t      base );
245
246/******************************************************************************************
247 * This function registers a local client thread in the waiting queue of a remote
248 * chdev descriptor, activates (i.e. unblock) the server thread associated to chdev,
249 * and blocks itself on the THREAD_BLOCKED_IO condition.
250 ******************************************************************************************
251 * @ chdev_xp  : extended pointer on remote chdev descriptor.
252 * @ thread    : local pointer on client thread.
253 *****************************************************************************************/
254void chdev_register_command( xptr_t            chdev_xp,
255                             struct thread_s * thread );
256
257/******************************************************************************************
258 * This function is executed by the server thread associated to a chdev descriptor.
259 * It executes an infinite loop to handle sequencially all commands registered by the
260 * client threads in the device waiting queue, until the queue is empty.
261 * The driver CMD function being blocking, these functions return only when the command
262 * is completed. These functions can use either a busy waiting policy, or a descheduling
263 * policy, blocking on the THREAD_BLOCKED_IO_ISR condition, and reactivated by the ISR.
264 * When the waiting queue is empty, the server thread blocks on the THREAD_BLOCKED_IO_CMD
265 * condition and deschedule. It is re-activated by a client thread registering a command.
266 ******************************************************************************************
267 * @ chdev   : local pointer on device descriptor.
268 *****************************************************************************************/
269void chdev_sequencial_server( chdev_t * chdev );
270
271
272#endif  /* _CHDEV_H_ */
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