| [75] | 1 | /* |
|---|
| 2 | * soclib_tty.c - soclib tty driver definition. |
|---|
| 3 | * |
|---|
| 4 | * Author 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-kernel; if not, write to the Free Software Foundation, |
|---|
| 21 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA |
|---|
| 22 | */ |
|---|
| 23 | |
|---|
| 24 | #include <dev_txt.h> |
|---|
| 25 | #include <chdev.h> |
|---|
| 26 | #include <spinlock.h> |
|---|
| 27 | |
|---|
| 28 | |
|---|
| 29 | /**************************************************************************************** |
|---|
| 30 | * This driver supports the soclib_multi_tty component. |
|---|
| 31 | * It implements the generic TXT device API: |
|---|
| 32 | * - transfer one single character from TTY to command "buffer" if to_mem is non-zero. |
|---|
| 33 | * - transfer "count" characters from command "buffer" to TTY if "to_mem is zero. |
|---|
| 34 | ***************************************************************************************/ |
|---|
| 35 | |
|---|
| 36 | /**************************************************************************************** |
|---|
| 37 | * SOCLIB_TTY registers offsets |
|---|
| 38 | ***************************************************************************************/ |
|---|
| 39 | |
|---|
| 40 | #define TTY_WRITE_REG 0 |
|---|
| 41 | #define TTY_STATUS_REG 1 |
|---|
| 42 | #define TTY_READ_REG 2 |
|---|
| 43 | #define TTY_CONFIG_REG 3 |
|---|
| 44 | |
|---|
| 45 | #define TTY_SPAN 4 // number of registers per channel |
|---|
| 46 | |
|---|
| 47 | /**************************************************************************************** |
|---|
| 48 | * masks for TTY_STATUS_REG |
|---|
| 49 | ***************************************************************************************/ |
|---|
| 50 | |
|---|
| 51 | #define TTY_STATUS_RX_FULL 1 // TTY_READ_REG full if 1 |
|---|
| 52 | #define TTY_STATUS_TX_FULL 2 // TTY_WRITE_REG full if 1 |
|---|
| 53 | |
|---|
| 54 | /**************************************************************************************** |
|---|
| 55 | * masks for TTY_CONFIG_REG |
|---|
| 56 | ***************************************************************************************/ |
|---|
| 57 | |
|---|
| 58 | #define TTY_CONFIG_RX_ENABLE 1 // TTY_RX IRQ enabled if 1 |
|---|
| 59 | #define TTY_CONFIG_TX_ENABLE 2 // TTY_TX IRQ enabled if 1 |
|---|
| 60 | |
|---|
| 61 | /**************************************************************************************** |
|---|
| 62 | * This function masks both the TTY_RX and TTY_TX IRQs. |
|---|
| 63 | * These IRQs are unmasked by the soclib_tty_cmd() function. |
|---|
| 64 | **************************************************************************************** |
|---|
| 65 | * @ chdev : pointer on the TXT chdev descriptor. |
|---|
| 66 | ***************************************************************************************/ |
|---|
| 67 | void soclib_tty_init( chdev_t * chdev ); |
|---|
| 68 | |
|---|
| 69 | /**************************************************************************************** |
|---|
| 70 | * This function handles the command registered in the thread descriptor identified |
|---|
| 71 | * by the <xp_thread> argument. |
|---|
| 72 | * - For the TXT_READ and TXT_WRITE commands, it only unmask the proper TTY_RX / TTY_TX |
|---|
| 73 | * IRQ, and blocks the TXT device server thread on the THREAD_BLOCKED_DEV_ISR, as the |
|---|
| 74 | * data transfer is done by the ISR. |
|---|
| 75 | * - For the TXT_SYNC_READ command, that should be only used by the kernel do display |
|---|
| 76 | * log or debug messages, it directly access the SOCLIB_TTY registers, using |
|---|
| 77 | * a busy waiting policy if required. |
|---|
| 78 | **************************************************************************************** |
|---|
| 79 | * @ thread_xp : extended pointer on client thread descriptor. |
|---|
| 80 | ***************************************************************************************/ |
|---|
| 81 | void soclib_tty_cmd( xptr_t thread_xp ); |
|---|
| 82 | |
|---|
| 83 | /**************************************************************************************** |
|---|
| 84 | * This ISR should be executed only for the TXT_READ and TXT_WRITE commands. |
|---|
| 85 | * It gets the command arguments from the first client thread in the TXT chdev queue: |
|---|
| 86 | * - if TXT_READ, it transfers one byte from the TTY_READ_REG to the command buffer. |
|---|
| 87 | * It simply returns for retry if TTY_READ_REG is empty. |
|---|
| 88 | * - if TXT_WRITE, it tries to transfer several bytes from the command buffer to the |
|---|
| 89 | * TTY_WRITE_REG. If the TTY_WRITE_REG is full, it updates the "count" and "buffer" |
|---|
| 90 | * command arguments and returns for retry. |
|---|
| 91 | * When the I/O operation is completed, it sets the status field in the command, unblocks |
|---|
| 92 | * the server thread, and unblocks the client thread. |
|---|
| 93 | **************************************************************************************** |
|---|
| 94 | * @ chdev : local pointer on TXT chdev descriptor. |
|---|
| 95 | ***************************************************************************************/ |
|---|
| 96 | void soclib_tty_isr( chdev_t * chdev ); |
|---|
| 97 | |
|---|
