dw_apb_uart.c revision 1.1
1/* $NetBSD: dw_apb_uart.c,v 1.1 2018/05/27 17:14:23 jmcneill Exp $ */ 2 3/*- 4 * Copyright (c) 2017 Jared McNeill <jmcneill@invisible.ca> 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 17 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 18 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 19 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 20 * BE 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 29#include <sys/cdefs.h> 30 31__KERNEL_RCSID(1, "$NetBSD: dw_apb_uart.c,v 1.1 2018/05/27 17:14:23 jmcneill Exp $"); 32 33#include <sys/param.h> 34#include <sys/bus.h> 35#include <sys/device.h> 36#include <sys/intr.h> 37#include <sys/systm.h> 38#include <sys/time.h> 39#include <sys/termios.h> 40 41#include <dev/ic/comvar.h> 42 43#include <dev/fdt/fdtvar.h> 44 45static int dw_apb_uart_match(device_t, cfdata_t, void *); 46static void dw_apb_uart_attach(device_t, device_t, void *); 47 48static const char * const compatible[] = { 49 "snps,dw-apb-uart", 50 NULL 51}; 52 53struct dw_apb_uart_softc { 54 struct com_softc ssc_sc; 55 void *ssc_ih; 56 57 struct clk *ssc_clk; 58 struct fdtbus_reset *ssc_rst; 59}; 60 61CFATTACH_DECL_NEW(dw_apb_uart, sizeof(struct dw_apb_uart_softc), 62 dw_apb_uart_match, dw_apb_uart_attach, NULL, NULL); 63 64static int 65dw_apb_uart_match(device_t parent, cfdata_t cf, void *aux) 66{ 67 struct fdt_attach_args * const faa = aux; 68 69 return of_match_compatible(faa->faa_phandle, compatible); 70} 71 72static void 73dw_apb_uart_attach(device_t parent, device_t self, void *aux) 74{ 75 struct dw_apb_uart_softc * const ssc = device_private(self); 76 struct com_softc * const sc = &ssc->ssc_sc; 77 struct fdt_attach_args * const faa = aux; 78 bus_space_handle_t bsh; 79 bus_space_tag_t bst; 80 char intrstr[128]; 81 bus_addr_t addr; 82 bus_size_t size; 83 u_int reg_shift; 84 int error; 85 86 if (fdtbus_get_reg(faa->faa_phandle, 0, &addr, &size) != 0) { 87 aprint_error(": couldn't get registers\n"); 88 return; 89 } 90 91 if (of_getprop_uint32(faa->faa_phandle, "reg-shift", ®_shift)) { 92 /* missing or bad reg-shift property, assume 2 */ 93 bst = faa->faa_a4x_bst; 94 } else { 95 if (reg_shift == 2) { 96 bst = faa->faa_a4x_bst; 97 } else if (reg_shift == 0) { 98 bst = faa->faa_bst; 99 } else { 100 aprint_error(": unsupported reg-shift value %d\n", 101 reg_shift); 102 return; 103 } 104 } 105 106 sc->sc_dev = self; 107 108 ssc->ssc_clk = fdtbus_clock_get_index(faa->faa_phandle, 0); 109 if (ssc->ssc_clk == NULL) { 110 aprint_error(": couldn't get clock\n"); 111 return; 112 } 113 if (clk_enable(ssc->ssc_clk) != 0) { 114 aprint_error(": couldn't enable clock\n"); 115 return; 116 } 117 118 ssc->ssc_rst = fdtbus_reset_get_index(faa->faa_phandle, 0); 119 if (ssc->ssc_rst && fdtbus_reset_deassert(ssc->ssc_rst) != 0) { 120 aprint_error(": couldn't de-assert reset\n"); 121 return; 122 } 123 124 sc->sc_frequency = clk_get_rate(ssc->ssc_clk); 125 sc->sc_type = COM_TYPE_DW_APB; 126 127 error = bus_space_map(bst, addr, size, 0, &bsh); 128 if (error) { 129 aprint_error(": couldn't map %#llx: %d", (uint64_t)addr, error); 130 return; 131 } 132 133 COM_INIT_REGS(sc->sc_regs, bst, bsh, addr); 134 135 com_attach_subr(sc); 136 137 if (!fdtbus_intr_str(faa->faa_phandle, 0, intrstr, sizeof(intrstr))) { 138 aprint_error_dev(self, "failed to decode interrupt\n"); 139 return; 140 } 141 142 ssc->ssc_ih = fdtbus_intr_establish(faa->faa_phandle, 0, IPL_SERIAL, 143 FDT_INTR_MPSAFE, comintr, sc); 144 if (ssc->ssc_ih == NULL) { 145 aprint_error_dev(self, "failed to establish interrupt on %s\n", 146 intrstr); 147 } 148 aprint_normal_dev(self, "interrupting on %s\n", intrstr); 149} 150 151/* 152 * Console support 153 */ 154 155static int 156dw_apb_uart_console_match(int phandle) 157{ 158 return of_match_compatible(phandle, compatible); 159} 160 161static void 162dw_apb_uart_console_consinit(struct fdt_attach_args *faa, u_int uart_freq) 163{ 164 const int phandle = faa->faa_phandle; 165 bus_space_tag_t bst = faa->faa_a4x_bst; 166 bus_addr_t addr; 167 tcflag_t flags; 168 int speed; 169 170 fdtbus_get_reg(phandle, 0, &addr, NULL); 171 speed = fdtbus_get_stdout_speed(); 172 if (speed < 0) 173 speed = 115200; /* default */ 174 flags = fdtbus_get_stdout_flags(); 175 176 if (comcnattach(bst, addr, speed, uart_freq, COM_TYPE_DW_APB, flags)) 177 panic("Cannot initialize dw-apb-uart console"); 178} 179 180static const struct fdt_console dw_apb_uart_console = { 181 .match = dw_apb_uart_console_match, 182 .consinit = dw_apb_uart_console_consinit, 183}; 184 185FDT_CONSOLE(dw_apb_uart, &dw_apb_uart_console); 186