uart_cpu_fdt.c revision 281077
1/*- 2 * Copyright (c) 2009-2010 The FreeBSD Foundation 3 * All rights reserved. 4 * 5 * This software was developed by Semihalf under sponsorship from 6 * the FreeBSD Foundation. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 */ 29 30#include <sys/cdefs.h> 31__FBSDID("$FreeBSD: head/sys/dev/uart/uart_cpu_fdt.c 281077 2015-04-04 18:45:25Z andrew $"); 32 33#include "opt_platform.h" 34 35#include <sys/param.h> 36#include <sys/bus.h> 37#include <sys/kernel.h> 38#include <sys/module.h> 39#include <sys/systm.h> 40 41#include <vm/vm.h> 42#include <vm/pmap.h> 43 44#include <machine/bus.h> 45#include <machine/fdt.h> 46 47#include <dev/fdt/fdt_common.h> 48#include <dev/ofw/ofw_bus.h> 49#include <dev/ofw/ofw_bus_subr.h> 50#include <dev/uart/uart.h> 51#include <dev/uart/uart_bus.h> 52#include <dev/uart/uart_cpu.h> 53#include <dev/uart/uart_cpu_fdt.h> 54 55/* 56 * UART console routines. 57 */ 58bus_space_tag_t uart_bus_space_io; 59bus_space_tag_t uart_bus_space_mem; 60 61int 62uart_cpu_eqres(struct uart_bas *b1, struct uart_bas *b2) 63{ 64 65 if (b1->bst != b2->bst) 66 return (0); 67 if (pmap_kextract(b1->bsh) == 0) 68 return (0); 69 if (pmap_kextract(b2->bsh) == 0) 70 return (0); 71 return ((pmap_kextract(b1->bsh) == pmap_kextract(b2->bsh)) ? 1 : 0); 72} 73 74static int 75phandle_chosen_propdev(phandle_t chosen, const char *name, phandle_t *node) 76{ 77 char buf[64]; 78 79 if (OF_getprop(chosen, name, buf, sizeof(buf)) <= 0) 80 return (ENXIO); 81 if ((*node = OF_finddevice(buf)) == -1) 82 return (ENXIO); 83 84 return (0); 85} 86 87static const struct ofw_compat_data * 88uart_fdt_find_compatible(phandle_t node, const struct ofw_compat_data *cd) 89{ 90 const struct ofw_compat_data *ocd; 91 92 for (ocd = cd; ocd->ocd_str != NULL; ocd++) { 93 if (fdt_is_compatible(node, ocd->ocd_str)) 94 return (ocd); 95 } 96 return (NULL); 97} 98 99static uintptr_t 100uart_fdt_find_by_node(phandle_t node, int class_list) 101{ 102 struct ofw_compat_data **cd; 103 const struct ofw_compat_data *ocd; 104 105 if (class_list) { 106 SET_FOREACH(cd, uart_fdt_class_set) { 107 ocd = uart_fdt_find_compatible(node, *cd); 108 if ((ocd != NULL) && (ocd->ocd_data != 0)) 109 return (ocd->ocd_data); 110 } 111 } else { 112 SET_FOREACH(cd, uart_fdt_class_and_device_set) { 113 ocd = uart_fdt_find_compatible(node, *cd); 114 if ((ocd != NULL) && (ocd->ocd_data != 0)) 115 return (ocd->ocd_data); 116 } 117 } 118 return (0); 119} 120 121int 122uart_cpu_getdev(int devtype, struct uart_devinfo *di) 123{ 124 const char *propnames[] = {"stdout-path", "linux,stdout-path", "stdout", 125 "stdin-path", "stdin", NULL}; 126 const char **name; 127 struct uart_class *class; 128 phandle_t node, chosen; 129 pcell_t shift, br, rclk; 130 u_long start, size, pbase, psize; 131 int err; 132 133 uart_bus_space_mem = fdtbus_bs_tag; 134 uart_bus_space_io = NULL; 135 136 /* Allow overriding the FDT using the environment. */ 137 class = &uart_ns8250_class; 138 err = uart_getenv(devtype, di, class); 139 if (!err) 140 return (0); 141 142 if (devtype != UART_DEV_CONSOLE) 143 return (ENXIO); 144 145 /* 146 * Retrieve /chosen/std{in,out}. 147 */ 148 node = -1; 149 if ((chosen = OF_finddevice("/chosen")) != -1) { 150 for (name = propnames; *name != NULL; name++) { 151 if (phandle_chosen_propdev(chosen, *name, &node) == 0) 152 break; 153 } 154 } 155 if (chosen == -1 || *name == NULL) 156 node = OF_finddevice("serial0"); /* Last ditch */ 157 158 if (node == -1) /* Can't find anything */ 159 return (ENXIO); 160 161 /* 162 * Retrieve serial attributes. 163 */ 164 uart_fdt_get_shift(node, &shift); 165 if (OF_getprop(node, "current-speed", &br, sizeof(br)) <= 0) 166 br = 0; 167 else 168 br = fdt32_to_cpu(br); 169 170 /* 171 * Check old style of UART definition first. Unfortunately, the common 172 * FDT processing is not possible if we have clock, power domains and 173 * pinmux stuff. 174 */ 175 class = (struct uart_class *)uart_fdt_find_by_node(node, 0); 176 if (class != NULL) { 177 if ((err = uart_fdt_get_clock(node, &rclk)) != 0) 178 return (err); 179 } else { 180 /* Check class only linker set */ 181 class = 182 (struct uart_class *)uart_fdt_find_by_node(node, 1); 183 if (class == NULL) 184 return (ENXIO); 185 rclk = 0; 186 } 187 188 /* 189 * Finalize configuration. 190 */ 191 di->bas.chan = 0; 192 di->bas.regshft = (u_int)shift; 193 di->baudrate = br; 194 di->bas.rclk = (u_int)rclk; 195 di->ops = uart_getops(class); 196 di->databits = 8; 197 di->stopbits = 1; 198 di->parity = UART_PARITY_NONE; 199 di->bas.bst = uart_bus_space_mem; 200 201 err = fdt_regsize(node, &start, &size); 202 if (err) 203 return (ENXIO); 204 err = fdt_get_range(OF_parent(node), 0, &pbase, &psize); 205 if (err) 206 pbase = 0; 207 208 start += pbase; 209 210 return (bus_space_map(di->bas.bst, start, size, 0, &di->bas.bsh)); 211} 212