1 /*- 2 * Copyright (c) 2013 Ian Lepore 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 7 * are met: 8 * 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 */ 26 27 #include "opt_platform.h" 28 29 #include <sys/cdefs.h> 30 __FBSDID("$FreeBSD$"); 31 32 #include <sys/param.h> 33 #include <sys/systm.h> 34 #include <sys/bus.h> 35 #include <sys/conf.h> 36 #include <sys/kernel.h> 37 #include <sys/sysctl.h> 38 #include <machine/bus.h> 39 40 #include <arm/ti/ti_prcm.h> 41 42 #include <dev/fdt/fdt_common.h> 43 #include <dev/ofw/ofw_bus.h> 44 #include <dev/ofw/ofw_bus_subr.h> 45 46 #include <dev/uart/uart.h> 47 #include <dev/uart/uart_cpu.h> 48 #include <dev/uart/uart_bus.h> 49 #include <dev/uart/uart_dev_ns8250.h> 50 51 #include "uart_if.h" 52 53 /* 54 * High-level UART interface. 55 */ 56 struct ti8250_softc { 57 struct ns8250_softc ns8250_base; 58 /*uint32_t mystuff;*/ 59 }; 60 61 #define MDR1_REG 8 62 #define MDR1_MODE_UART 0 63 #define MDR1_MODE_DISABLE 7 64 #define SYSCC_REG 15 65 #define SYSCC_SOFTRESET (1 << 1) 66 #define SYSS_REG 16 67 #define SYSS_STATUS_RESETDONE (1 << 0) 68 69 static int 70 ti8250_bus_probe(struct uart_softc *sc) 71 { 72 int status; 73 int devid; 74 clk_ident_t clkid; 75 pcell_t prop; 76 phandle_t node; 77 78 /* 79 * Get the device id from FDT. If it's not there we can't turn on the 80 * right clocks, so bail, unless we're doing unit 0. We assume that's 81 * the serial console, whose clock isn't controllable anyway, and we 82 * sure don't want to break the console because of a config error. 83 */ 84 node = ofw_bus_get_node(sc->sc_dev); 85 if ((OF_getprop(node, "uart-device-id", &prop, sizeof(prop))) <= 0) { 86 device_printf(sc->sc_dev, 87 "missing uart-device-id attribute in FDT\n"); 88 if (device_get_unit(sc->sc_dev) != 0) 89 return (ENXIO); 90 devid = 0; 91 } else 92 devid = fdt32_to_cpu(prop); 93 94 /* Enable clocks for this device. We can't continue if that fails. */ 95 clkid = UART0_CLK + devid; 96 if ((status = ti_prcm_clk_enable(clkid)) != 0) 97 return (status); 98 99 /* 100 * Set the hardware to disabled mode, do a full device reset, then set 101 * it to uart mode. Most devices will be reset-and-disabled already, 102 * but you never know what a bootloader might have done. 103 */ 104 uart_setreg(&sc->sc_bas, MDR1_REG, MDR1_MODE_DISABLE); 105 uart_setreg(&sc->sc_bas, SYSCC_REG, SYSCC_SOFTRESET); 106 while (uart_getreg(&sc->sc_bas, SYSS_REG) & SYSS_STATUS_RESETDONE) 107 continue; 108 uart_setreg(&sc->sc_bas, MDR1_REG, MDR1_MODE_UART); 109 110 status = ns8250_bus_probe(sc); 111 if (status == 0) 112 device_set_desc(sc->sc_dev, "TI UART (16550 compatible)"); 113 114 return (status); 115 } 116 117 static kobj_method_t ti8250_methods[] = { 118 KOBJMETHOD(uart_probe, ti8250_bus_probe), 119 120 KOBJMETHOD(uart_attach, ns8250_bus_attach), 121 KOBJMETHOD(uart_detach, ns8250_bus_detach), 122 KOBJMETHOD(uart_flush, ns8250_bus_flush), 123 KOBJMETHOD(uart_getsig, ns8250_bus_getsig), 124 KOBJMETHOD(uart_ioctl, ns8250_bus_ioctl), 125 KOBJMETHOD(uart_ipend, ns8250_bus_ipend), 126 KOBJMETHOD(uart_param, ns8250_bus_param), 127 KOBJMETHOD(uart_receive, ns8250_bus_receive), 128 KOBJMETHOD(uart_setsig, ns8250_bus_setsig), 129 KOBJMETHOD(uart_transmit, ns8250_bus_transmit), 130 KOBJMETHOD_END 131 }; 132 133 struct uart_class uart_ti8250_class = { 134 "ti8250", 135 ti8250_methods, 136 sizeof(struct ti8250_softc), 137 .uc_ops = &uart_ns8250_ops, 138 .uc_range = 0x88, 139 .uc_rclk = 48000000 140 }; 141 142