/* * chdev.h - channel device (chdev) descriptor definition. * * Authors Alain Greiner (2016) * * Copyright (c) UPMC Sorbonne Universites * * This file is part of ALMOS-MKH * * ALMOS-MKH is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License as published by * the Free Software Foundation; version 2.0 of the License. * * ALMOS-MKH is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public License * along with ALMOS-MKH; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */ #ifndef _CHDEV_H_ #define _CHDEV_H_ #include #include #include #include #include #include #include #include #include #include /****************************************************************************************** * Channel Device descriptor definition * * This file defines the kernel representation of a generic (i.e. implementation * independant) Channel Device descriptor (in brief "chdev"). * ALMOS-MKH supports multi-channels peripherals, and defines one separated chdev * descriptor for each channel (and for each RX/TX direction for the NIC and TXT devices). * Each chdev contains a waiting queue, registering the "client threads" requests, * and an associated "server thread", handling these requests. * These descriptors are physically distributed on all clusters to minimize contention. * Therefore a given I/O operation involve generally three clusters: * - the client cluster, containing the client thread, * - the server cluster, containing the chdev and the server thread, * - the I/O cluster, containing the physical device. *****************************************************************************************/ /**** Forward declarations ****/ struct chdev_s; struct thread_s; struct boot_info_s; /****************************************************************************************** * These macros extract the functionality and the implementation from the peripheral type. *****************************************************************************************/ #define FUNC_FROM_TYPE( type ) ((uint32_t)(type>>16)) #define IMPL_FROM_TYPE( type ) ((uint32_t)(type & 0x0000FFFF)) /****************************************************************************************** * This define the generic prototypes for the three functions that must be defined * by the drivers implementing a generic device: * - "cmd" : start a blocking I/O operation. * - "isr" : complete an I/O operation. * - "aux" : not for all drivers (implement special functions) * The "cmd", "isr", and "aux" driver functions are registered in the generic chdev * descriptor at kernel init, and are called to start and complete an I/O operation. *****************************************************************************************/ typedef void (dev_ini_t) ( xptr_t dev ); typedef void (dev_cmd_t) ( xptr_t thread ); typedef void (dev_isr_t) ( struct chdev_s * dev ); typedef void (dev_aux_t) ( void * args ); /****************************************************************************************** * This enum defines the supported generic device types. * These types are functionnal types: all (architecture specific) implementations * provide the same set of operations and the same driver API. * This enum must be consistent with the enum in files arch_info.h, and arch_class.py. * * WARNING : The ICU device exist in boot_info to specify the base address of the * distributed LAPIC controler, but it does not exist as a chdev in the kernel, * as it is hidden in the driver associated to the PIC device. *****************************************************************************************/ enum dev_func_type { DEV_FUNC_RAM = 0, DEV_FUNC_ROM = 1, DEV_FUNC_FBF = 2, DEV_FUNC_IOB = 3, DEV_FUNC_IOC = 4, DEV_FUNC_MMC = 5, DEV_FUNC_DMA = 6, DEV_FUNC_NIC = 7, DEV_FUNC_TIM = 8, DEV_FUNC_TXT = 9, DEV_FUNC_ICU = 10, DEV_FUNC_PIC = 11, DEV_FUNC_NR = 12, }; /****************************************************************************************** * This structure defines a chdev descriptor. * For multi-channels device, there is one chdev descriptor per channel. * This structure is NOT replicated, and can be located in any cluster. * One kernel thread, in charge of handling the commands registered in the waiting queue * of client threads is associated to each chdev descriptor (not for ICU, PIC, IOB). * For each device type ***, the specific extension is defined in the "dev_***.h" file. *****************************************************************************************/ typedef struct chdev_s { uint32_t func; /*! peripheral functionnal type */ uint32_t impl; /*! peripheral inplementation subtype */ uint32_t channel; /*! channel index */ bool_t is_rx; /*! relevant for NIC and TXT peripherals */ xptr_t base; /*! extended pointer on channel device segment */ char name[16]; /*! name (required by DEVFS) */ dev_cmd_t * cmd; /*! local pointer on driver CMD function */ dev_isr_t * isr; /*! local pointer on driver ISR function */ dev_aux_t * aux; /*! local pointer on driver AUX function */ struct thread_s * server; /*! local pointer on associated server thread */ uint32_t irq_type; /*! associated IRQ type in local ICU */ uint32_t irq_id; /*! associated IRQ index in local ICU */ remote_spinlock_t wait_lock; /*! lock protecting exclusive access to queue */ xlist_entry_t wait_root; /*! root of waiting threads queue */ union { iob_extend_t iob; /*! IOB specific extension */ ioc_extend_t ioc; /*! IOC specific extension */ nic_extend_t nic; /*! NIC specific extension */ pic_extend_t pic; /*! PIC specific extension */ fbf_extend_t fbf; /*! FBF specific extension */ txt_extend_t txt; /*! TXT specific extension */ } ext; } chdev_t; /****************************************************************************************** * This structure defines the channel_devices descriptors directory. * Each entry in this structure contains an extended pointer on a chdev descriptor. * There is one entry per channel OR per cluster, depending on peripheral type. * This structure is replicated in each cluster, and is initialised during kernel init. * It is used for fast access to a device descriptor, from type and channel for an * external peripheral, or from type and cluster for a hared internal peripheral. * - a "shared" chdev can be accessed by any thread running in any cluster. * - a "private" chdev can only be accessed by a thread running in local cluster. *****************************************************************************************/ typedef struct chdev_directory_s { xptr_t iob; // external / single channel / shared xptr_t pic; // external / single channel / shared xptr_t ioc[CONFIG_MAX_IOC_CHANNELS]; // external / multi-channels / shared xptr_t fbf[CONFIG_MAX_FBF_CHANNELS]; // external / multi-channels / shared xptr_t txt_rx[CONFIG_MAX_TXT_CHANNELS]; // external / multi-channels / shared xptr_t txt_tx[CONFIG_MAX_TXT_CHANNELS]; // external / multi-channels / shared xptr_t nic_rx[CONFIG_MAX_NIC_CHANNELS]; // external / multi-channels / shared xptr_t nic_tx[CONFIG_MAX_NIC_CHANNELS]; // external / multi-channels / shared xptr_t mmc[CONFIG_MAX_CLUSTERS]; // internal / single channel / shared xptr_t dma[CONFIG_MAX_DMA_CHANNELS]; // internal / multi-channels / private } chdev_directory_t; /****************************************************************************************** * This function display relevant values for a chdev descriptor. ****************************************************************************************** * @ chdev : pointer on chdev. *****************************************************************************************/ void chdev_print( chdev_t * chdev ); /****************************************************************************************** * This function returns a printable string for a device functionnal types. ****************************************************************************************** * @ func_type : functionnal type. * @ return pointer on string. *****************************************************************************************/ char * chdev_func_str( uint32_t func_type ); /****************************************************************************************** * This function allocates memory and initializes a chdev descriptor in local cluster, * from arguments values. It should be called by a local thread. * The device specific fields are initialised later. ****************************************************************************************** * @ func : functionnal type. * @ impl : implementation type. * @ channel : channel index / for multi-channels peripherals. * @ is_rx : for NIC peripheral / NIC RX if true / NIC TX if false. * @ base : extended pointer on peripheral segment base. * @ return a local pointer on created chdev / return NULL if failure. *****************************************************************************************/ chdev_t * chdev_create( uint32_t func, uint32_t impl, uint32_t channel, bool_t is_rx, xptr_t base ); /****************************************************************************************** * This function registers the calling thread in the waiting queue of a remote * chdev descriptor, activates (i.e. unblock) the server thread associated to chdev, * and blocks itself on the THREAD_BLOCKED_IO condition. ****************************************************************************************** * @ chdev_xp : extended pointer on remote chdev descriptor. *****************************************************************************************/ void chdev_register_command( xptr_t chdev_xp ); /****************************************************************************************** * This function is executed by the server thread associated to a chdev descriptor. * It executes an infinite loop to handle sequencially all commands registered by the * client threads in the device waiting queue, until the queue is empty. * The driver CMD function being blocking, these functions return only when the command * is completed. These functions can use either a busy waiting policy, or a descheduling * policy, blocking on the THREAD_BLOCKED_IO_ISR condition, and reactivated by the ISR. * When the waiting queue is empty, the server thread blocks on the THREAD_BLOCKED_IO_CMD * condition and deschedule. It is re-activated by a client thread registering a command. ****************************************************************************************** * @ chdev : local pointer on device descriptor. *****************************************************************************************/ void chdev_sequencial_server( chdev_t * chdev ); /****************************************************************************************** * This function returns an extended pointer on the chdev associated to a pseudo file * descriptor (type INODE_TYPE_DEV) identified by the argument. * It can be called by a thread running in any cluster. * It enters kernel panic if the inode has not the expected type. ****************************************************************************************** * @ file_xp : extended pointer on the pseudo file descriptor. * @ return an extended pointer on chdev. *****************************************************************************************/ xptr_t chdev_from_file( xptr_t file_xp ); /****************************************************************************************** * This function displays the local copy of the external chdevs directory. * (global variable replicated in all clusters) *****************************************************************************************/ void chdev_dir_display(); /****************************************************************************************** * This function displays the list of threads registered in the queue associated * to the chdev identified by the . ****************************************************************************************** * # root_xp : extended pointer *****************************************************************************************/ void chdev_queue_display( xptr_t chdev_xp ); #endif /* _CHDEV_H_ */