dw_apb_uart.c revision 1.13
1 /* $NetBSD: dw_apb_uart.c,v 1.13 2025/09/06 22:53:48 thorpej Exp $ */ 2 3 /*- 4 * Copyright (c) 2017 Jared McNeill <jmcneill (at) 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 1.13 2025/09/06 22:53:48 thorpej 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 #include <dev/fdt/fdt_console.h> 45 46 static int dw_apb_uart_match(device_t, cfdata_t, void *); 47 static void dw_apb_uart_attach(device_t, device_t, void *); 48 49 static const struct device_compatible_entry compat_data[] = { 50 { .compat = "snps,dw-apb-uart" }, 51 DEVICE_COMPAT_EOL 52 }; 53 54 struct dw_apb_uart_softc { 55 struct com_softc ssc_sc; 56 void *ssc_ih; 57 58 struct clk *ssc_clk; 59 struct clk *ssc_pclk; 60 struct fdtbus_reset *ssc_rst; 61 }; 62 63 CFATTACH_DECL_NEW(dw_apb_uart, sizeof(struct dw_apb_uart_softc), 64 dw_apb_uart_match, dw_apb_uart_attach, NULL, NULL); 65 66 static int 67 dw_apb_uart_match(device_t parent, cfdata_t cf, void *aux) 68 { 69 struct fdt_attach_args * const faa = aux; 70 71 return of_compatible_match(faa->faa_phandle, compat_data); 72 } 73 74 static void 75 dw_apb_uart_attach(device_t parent, device_t self, void *aux) 76 { 77 struct dw_apb_uart_softc * const ssc = device_private(self); 78 struct com_softc * const sc = &ssc->ssc_sc; 79 struct fdt_attach_args * const faa = aux; 80 const int phandle = faa->faa_phandle; 81 bus_space_tag_t bst = faa->faa_bst; 82 bus_space_handle_t bsh; 83 char intrstr[128]; 84 bus_addr_t addr; 85 bus_size_t size; 86 u_int reg_shift, reg_iowidth; 87 int error; 88 89 if (fdtbus_get_reg(phandle, 0, &addr, &size) != 0) { 90 aprint_error(": couldn't get registers\n"); 91 return; 92 } 93 94 if (of_getprop_uint32(phandle, "reg-shift", ®_shift)) { 95 /* missing or bad reg-shift property, assume 2 */ 96 reg_shift = 2; 97 } 98 if (of_getprop_uint32(phandle, "reg-io-width", ®_iowidth)) { 99 /* missing or bad reg-io-width property, assume 1 */ 100 reg_iowidth = 1; 101 } 102 103 sc->sc_dev = self; 104 105 ssc->ssc_clk = fdtbus_clock_get_index(phandle, 0); 106 if (ssc->ssc_clk == NULL) { 107 aprint_error(": couldn't get clock\n"); 108 return; 109 } 110 if (clk_enable(ssc->ssc_clk) != 0) { 111 aprint_error(": couldn't enable clock\n"); 112 return; 113 } 114 115 ssc->ssc_pclk = fdtbus_clock_get(phandle, "apb_pclk"); 116 if (ssc->ssc_pclk != NULL && clk_enable(ssc->ssc_pclk) != 0) { 117 aprint_error(": couldn't enable peripheral clock\n"); 118 return; 119 } 120 121 ssc->ssc_rst = fdtbus_reset_get_index(phandle, 0); 122 if (ssc->ssc_rst && fdtbus_reset_deassert(ssc->ssc_rst) != 0) { 123 aprint_error(": couldn't de-assert reset\n"); 124 return; 125 } 126 127 sc->sc_frequency = clk_get_rate(ssc->ssc_clk); 128 sc->sc_type = COM_TYPE_DW_APB; 129 130 error = bus_space_map(bst, addr, size, 0, &bsh); 131 if (error) { 132 aprint_error(": couldn't map %#" PRIx64 ": %d", (uint64_t)addr, error); 133 return; 134 } 135 136 com_init_regs_stride_width(&sc->sc_regs, bst, bsh, addr, reg_shift, reg_iowidth); 137 138 com_attach_subr(sc); 139 140 if (!fdtbus_intr_str(phandle, 0, intrstr, sizeof(intrstr))) { 141 aprint_error_dev(self, "failed to decode interrupt\n"); 142 return; 143 } 144 145 ssc->ssc_ih = fdtbus_intr_establish_xname(phandle, 0, 146 IPL_SERIAL, FDT_INTR_MPSAFE, comintr, sc, device_xname(self)); 147 if (ssc->ssc_ih == NULL) { 148 aprint_error_dev(self, "failed to establish interrupt on %s\n", 149 intrstr); 150 } 151 aprint_normal_dev(self, "interrupting on %s\n", intrstr); 152 } 153 154 /* 155 * Console support 156 */ 157 158 static int 159 dw_apb_uart_console_match(int phandle) 160 { 161 return of_compatible_match(phandle, compat_data); 162 } 163 164 static void 165 dw_apb_uart_console_consinit(struct fdt_attach_args *faa, u_int uart_freq) 166 { 167 const int phandle = faa->faa_phandle; 168 bus_space_tag_t bst = faa->faa_bst; 169 bus_space_handle_t dummy_bsh; 170 struct com_regs regs; 171 bus_addr_t addr; 172 tcflag_t flags; 173 u_int reg_shift, reg_iowidth; 174 int speed; 175 176 fdtbus_get_reg(phandle, 0, &addr, NULL); 177 speed = fdtbus_get_stdout_speed(); 178 if (speed < 0) 179 speed = 115200; /* default */ 180 flags = fdtbus_get_stdout_flags(); 181 182 if (of_getprop_uint32(phandle, "reg-shift", ®_shift)) { 183 /* missing or bad reg-shift property, assume 2 */ 184 reg_shift = 2; 185 } 186 if (of_getprop_uint32(phandle, "reg-io-width", ®_iowidth)) { 187 /* missing or bad reg-io-width property, assume 1 */ 188 reg_iowidth = 1; 189 } 190 191 memset(&dummy_bsh, 0, sizeof(dummy_bsh)); 192 com_init_regs_stride_width(®s, bst, dummy_bsh, addr, reg_shift, reg_iowidth); 193 194 if (comcnattach1(®s, speed, uart_freq, COM_TYPE_DW_APB, flags)) 195 panic("Cannot initialize dw-apb-uart console"); 196 } 197 198 static const struct fdt_console dw_apb_uart_console = { 199 .match = dw_apb_uart_console_match, 200 .consinit = dw_apb_uart_console_consinit, 201 }; 202 203 FDT_CONSOLE(dw_apb_uart, &dw_apb_uart_console); 204
Indexes created Sat Sep 27 22:09:54 GMT 2025