1 /* SPDX-License-Identifier: BSD-2-Clause */ 2 /* 3 * Copyright (c) 2016, Linaro Limited 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions are met: 8 * 9 * 1. Redistributions of source code must retain the above copyright notice, 10 * this list of conditions and the following disclaimer. 11 * 12 * 2. Redistributions in binary form must reproduce the above copyright notice, 13 * this list of conditions and the following disclaimer in the documentation 14 * and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 17 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE 20 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 26 * POSSIBILITY OF SUCH DAMAGE. 27 */ 28 #ifndef __DRIVERS_SERIAL_H 29 #define __DRIVERS_SERIAL_H 30 31 #include <assert.h> 32 #include <stdbool.h> 33 #include <types_ext.h> 34 #include <mm/core_memprot.h> 35 #include <mm/core_mmu.h> 36 37 struct serial_chip { 38 const struct serial_ops *ops; 39 }; 40 41 struct serial_ops { 42 void (*putc)(struct serial_chip *chip, int ch); 43 void (*flush)(struct serial_chip *chip); 44 bool (*have_rx_data)(struct serial_chip *chip); 45 int (*getchar)(struct serial_chip *chip); 46 }; 47 48 struct serial_driver { 49 /* Allocate device data and return the inner serial_chip */ 50 struct serial_chip *(*dev_alloc)(void); 51 /* 52 * Initialize device from FDT node. @parms is device-specific, 53 * its meaning is as defined by the DT bindings for the characters 54 * following the ":" in /chosen/stdout-path. Typically for UART 55 * devices this is <baud>{<parity>{<bits>{<flow>}}} where: 56 * baud - baud rate in decimal 57 * parity - 'n' (none), 'o', (odd) or 'e' (even) 58 * bits - number of data bits 59 * flow - 'r' (rts) 60 * For example: 115200n8r 61 */ 62 int (*dev_init)(struct serial_chip *dev, const void *fdt, 63 int offset, const char *parms); 64 void (*dev_free)(struct serial_chip *dev); 65 }; 66 67 struct io_pa_va { 68 paddr_t pa; 69 vaddr_t va; 70 }; 71 72 /* 73 * Helper function to return a physical or virtual address for a device, 74 * depending on whether the MMU is enabled or not 75 */ 76 static inline vaddr_t io_pa_or_va(struct io_pa_va *p) 77 { 78 assert(p->pa); 79 if (cpu_mmu_enabled()) { 80 if (!p->va) 81 p->va = (vaddr_t)phys_to_virt_io(p->pa); 82 assert(p->va); 83 return p->va; 84 } 85 return p->pa; 86 } 87 88 #endif /*__DRIVERS_SERIASERIAL_H*/ 89