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