1 /*- 2 * Copyright (c) 2016 Jared McNeill <jmcneill@invisible.ca> 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 13 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 14 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 15 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 16 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 17 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 18 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 19 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 20 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 21 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 22 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 23 * SUCH DAMAGE. 24 */ 25 26 #include <sys/cdefs.h> 27 #include <sys/param.h> 28 #include <sys/systm.h> 29 #include <sys/bus.h> 30 #include <sys/kernel.h> 31 #include <sys/module.h> 32 #include <machine/bus.h> 33 34 #include <dev/uart/uart.h> 35 #include <dev/uart/uart_bus.h> 36 #include <dev/uart/uart_cpu_fdt.h> 37 #include <dev/uart/uart_dev_ns8250.h> 38 39 #include <dev/ofw/ofw_bus.h> 40 #include <dev/ofw/ofw_bus_subr.h> 41 42 #include <dev/extres/clk/clk.h> 43 #include <dev/extres/hwreset/hwreset.h> 44 45 #include "uart_if.h" 46 47 struct snps_softc { 48 struct ns8250_softc ns8250; 49 50 clk_t baudclk; 51 clk_t apb_pclk; 52 hwreset_t reset; 53 }; 54 55 /* 56 * To use early printf on 64 bits Allwinner SoC, add to kernel config 57 * options SOCDEV_PA=0x0 58 * options SOCDEV_VA=0x40000000 59 * options EARLY_PRINTF 60 * 61 * To use early printf on 32 bits Allwinner SoC, add to kernel config 62 * options SOCDEV_PA=0x01C00000 63 * options SOCDEV_VA=0x10000000 64 * options EARLY_PRINTF 65 * 66 * remove the if 0 67 */ 68 #if 0 69 #ifdef EARLY_PRINTF 70 static void 71 uart_snps_early_putc(int c) 72 { 73 volatile uint32_t *stat; 74 volatile uint32_t *tx; 75 76 #ifdef ALLWINNER_64 77 stat = (uint32_t *) (SOCDEV_VA + 0x1C2807C); 78 tx = (uint32_t *) (SOCDEV_VA + 0x1C28000); 79 #endif 80 #ifdef ALLWINNER_32 81 stat = (uint32_t *) (SOCDEV_VA + 0x2807C); 82 tx = (uint32_t *) (SOCDEV_VA + 0x28000); 83 #endif 84 85 while ((*stat & (1 << 2)) == 0) 86 continue; 87 *tx = c; 88 } 89 early_putc_t *early_putc = uart_snps_early_putc; 90 #endif /* EARLY_PRINTF */ 91 #endif 92 93 static kobj_method_t snps_methods[] = { 94 KOBJMETHOD(uart_probe, ns8250_bus_probe), 95 KOBJMETHOD(uart_attach, ns8250_bus_attach), 96 KOBJMETHOD(uart_detach, ns8250_bus_detach), 97 KOBJMETHOD(uart_flush, ns8250_bus_flush), 98 KOBJMETHOD(uart_getsig, ns8250_bus_getsig), 99 KOBJMETHOD(uart_ioctl, ns8250_bus_ioctl), 100 KOBJMETHOD(uart_ipend, ns8250_bus_ipend), 101 KOBJMETHOD(uart_param, ns8250_bus_param), 102 KOBJMETHOD(uart_receive, ns8250_bus_receive), 103 KOBJMETHOD(uart_setsig, ns8250_bus_setsig), 104 KOBJMETHOD(uart_transmit, ns8250_bus_transmit), 105 KOBJMETHOD(uart_grab, ns8250_bus_grab), 106 KOBJMETHOD(uart_ungrab, ns8250_bus_ungrab), 107 KOBJMETHOD_END 108 }; 109 110 struct uart_class uart_snps_class = { 111 "snps", 112 snps_methods, 113 sizeof(struct snps_softc), 114 .uc_ops = &uart_ns8250_ops, 115 .uc_range = 8, 116 .uc_rclk = 0, 117 }; 118 119 static struct ofw_compat_data compat_data[] = { 120 { "snps,dw-apb-uart", (uintptr_t)&uart_snps_class }, 121 { "marvell,armada-38x-uart", (uintptr_t)&uart_snps_class }, 122 { NULL, (uintptr_t)NULL } 123 }; 124 UART_FDT_CLASS(compat_data); 125 126 static int 127 snps_get_clocks(device_t dev, clk_t *baudclk, clk_t *apb_pclk) 128 { 129 130 *baudclk = NULL; 131 *apb_pclk = NULL; 132 133 /* Baud clock is either named "baudclk", or there is a single 134 * unnamed clock. 135 */ 136 if (clk_get_by_ofw_name(dev, 0, "baudclk", baudclk) != 0 && 137 clk_get_by_ofw_index(dev, 0, 0, baudclk) != 0) 138 return (ENOENT); 139 140 /* APB peripheral clock is optional */ 141 (void)clk_get_by_ofw_name(dev, 0, "apb_pclk", apb_pclk); 142 143 return (0); 144 } 145 146 static int 147 snps_probe(device_t dev) 148 { 149 struct snps_softc *sc; 150 struct uart_class *uart_class; 151 phandle_t node; 152 uint32_t shift, iowidth, clock; 153 uint64_t freq; 154 int error; 155 clk_t baudclk, apb_pclk; 156 hwreset_t reset; 157 158 if (!ofw_bus_status_okay(dev)) 159 return (ENXIO); 160 161 uart_class = (struct uart_class *)ofw_bus_search_compatible(dev, 162 compat_data)->ocd_data; 163 if (uart_class == NULL) 164 return (ENXIO); 165 166 freq = 0; 167 sc = device_get_softc(dev); 168 sc->ns8250.base.sc_class = uart_class; 169 170 node = ofw_bus_get_node(dev); 171 if (OF_getencprop(node, "reg-shift", &shift, sizeof(shift)) <= 0) 172 shift = 0; 173 if (OF_getencprop(node, "reg-io-width", &iowidth, sizeof(iowidth)) <= 0) 174 iowidth = 1; 175 if (OF_getencprop(node, "clock-frequency", &clock, sizeof(clock)) <= 0) 176 clock = 0; 177 178 if (hwreset_get_by_ofw_idx(dev, 0, 0, &reset) == 0) { 179 error = hwreset_deassert(reset); 180 if (error != 0) { 181 device_printf(dev, "cannot de-assert reset\n"); 182 return (error); 183 } 184 } 185 186 if (snps_get_clocks(dev, &baudclk, &apb_pclk) == 0) { 187 error = clk_enable(baudclk); 188 if (error != 0) { 189 device_printf(dev, "cannot enable baud clock\n"); 190 return (error); 191 } 192 if (apb_pclk != NULL) { 193 error = clk_enable(apb_pclk); 194 if (error != 0) { 195 device_printf(dev, 196 "cannot enable peripheral clock\n"); 197 return (error); 198 } 199 } 200 201 if (clock == 0) { 202 error = clk_get_freq(baudclk, &freq); 203 if (error != 0) { 204 device_printf(dev, "cannot get frequency\n"); 205 return (error); 206 } 207 clock = (uint32_t)freq; 208 } 209 } 210 211 if (bootverbose && clock == 0) 212 device_printf(dev, "could not determine frequency\n"); 213 214 error = uart_bus_probe(dev, (int)shift, (int)iowidth, (int)clock, 0, 0, UART_F_BUSY_DETECT); 215 if (error > 0) 216 return (error); 217 218 /* XXX uart_bus_probe has changed the softc, so refresh it */ 219 sc = device_get_softc(dev); 220 221 /* Store clock and reset handles for detach */ 222 sc->baudclk = baudclk; 223 sc->apb_pclk = apb_pclk; 224 sc->reset = reset; 225 226 return (BUS_PROBE_VENDOR); 227 } 228 229 static int 230 snps_detach(device_t dev) 231 { 232 struct snps_softc *sc; 233 clk_t baudclk, apb_pclk; 234 hwreset_t reset; 235 int error; 236 237 sc = device_get_softc(dev); 238 baudclk = sc->baudclk; 239 apb_pclk = sc->apb_pclk; 240 reset = sc->reset; 241 242 error = uart_bus_detach(dev); 243 if (error != 0) 244 return (error); 245 246 if (reset != NULL) { 247 error = hwreset_assert(reset); 248 if (error != 0) { 249 device_printf(dev, "cannot assert reset\n"); 250 return (error); 251 } 252 hwreset_release(reset); 253 } 254 if (apb_pclk != NULL) { 255 error = clk_release(apb_pclk); 256 if (error != 0) { 257 device_printf(dev, "cannot release peripheral clock\n"); 258 return (error); 259 } 260 } 261 if (baudclk != NULL) { 262 error = clk_release(baudclk); 263 if (error != 0) { 264 device_printf(dev, "cannot release baud clock\n"); 265 return (error); 266 } 267 } 268 269 return (0); 270 } 271 272 static device_method_t snps_bus_methods[] = { 273 /* Device interface */ 274 DEVMETHOD(device_probe, snps_probe), 275 DEVMETHOD(device_attach, uart_bus_attach), 276 DEVMETHOD(device_detach, snps_detach), 277 DEVMETHOD_END 278 }; 279 280 static driver_t snps_uart_driver = { 281 uart_driver_name, 282 snps_bus_methods, 283 sizeof(struct snps_softc) 284 }; 285 286 DRIVER_MODULE(uart_snps, simplebus, snps_uart_driver, 0, 0); 287