1 /*- 2 * Copyright (c) 2012, 2013 The FreeBSD Foundation 3 * 4 * This software was developed by Oleksandr Rybalko under sponsorship 5 * from the FreeBSD Foundation. 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 AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 /* Simple UART console driver for Freescale i.MX515 */ 30 31 #include <sys/types.h> 32 #include <sys/param.h> 33 #include <sys/systm.h> 34 #include <sys/cons.h> 35 #include <sys/consio.h> 36 #include <sys/kernel.h> 37 38 /* Allow it to be predefined, to be able to use another UART for console */ 39 #ifndef IMX_UART_BASE 40 #define IMX_UART_BASE 0xe3fbc000 /* imx51 UART1 */ 41 #endif 42 43 #define IMX_RXD 0x00 44 #define IMX_TXD 0x40 45 46 #define IMX_UFCR 0x90 47 #define IMX_USR1 0x94 48 #define IMX_USR1_TRDY (1 << 13) 49 50 #define IMX_USR2 0x98 51 #define IMX_USR2_RDR (1 << 0) 52 #define IMX_USR2_TXFE (1 << 14) 53 #define IMX_USR2_TXDC (1 << 3) 54 55 #define IMX_UTS 0xb4 56 #define IMX_UTS_TXFULL (1 << 4) 57 58 /* 59 * The base address of the uart registers. 60 * 61 * This is global so that it can be changed on the fly from the outside. For 62 * example, set imx_uart_base=physaddr and then call cninit() as the first two 63 * lines of initarm() and enjoy printf() availability through the tricky bits of 64 * startup. After initarm() switches from physical to virtual addressing, just 65 * set imx_uart_base=virtaddr and printf keeps working. 66 */ 67 uint32_t imx_uart_base = IMX_UART_BASE; 68 69 /* 70 * uart related funcs 71 */ 72 static uint32_t 73 ub_getreg(uint32_t off) 74 { 75 76 return *((volatile uint32_t *)(imx_uart_base + off)); 77 } 78 79 static void 80 ub_setreg(uint32_t off, uint32_t val) 81 { 82 83 *((volatile uint32_t *)(imx_uart_base + off)) = val; 84 } 85 86 static int 87 ub_tstc(void) 88 { 89 90 return ((ub_getreg(IMX_USR2) & IMX_USR2_RDR) ? 1 : 0); 91 } 92 93 static int 94 ub_getc(void) 95 { 96 97 while (!ub_tstc()); 98 __asm __volatile("nop"); 99 100 return (ub_getreg(IMX_RXD) & 0xff); 101 } 102 103 static void 104 ub_putc(unsigned char c) 105 { 106 107 if (c == '\n') 108 ub_putc('\r'); 109 110 while (ub_getreg(IMX_UTS) & IMX_UTS_TXFULL) 111 __asm __volatile("nop"); 112 113 ub_setreg(IMX_TXD, c); 114 } 115 116 static cn_probe_t uart_cnprobe; 117 static cn_init_t uart_cninit; 118 static cn_term_t uart_cnterm; 119 static cn_getc_t uart_cngetc; 120 static cn_putc_t uart_cnputc; 121 static cn_grab_t uart_cngrab; 122 static cn_ungrab_t uart_cnungrab; 123 124 static void 125 uart_cngrab(struct consdev *cp) 126 { 127 128 } 129 130 static void 131 uart_cnungrab(struct consdev *cp) 132 { 133 134 } 135 136 static void 137 uart_cnprobe(struct consdev *cp) 138 { 139 140 sprintf(cp->cn_name, "uart"); 141 cp->cn_pri = CN_NORMAL; 142 } 143 144 static void 145 uart_cninit(struct consdev *cp) 146 { 147 148 /* Init fifo trigger levels to 32 bytes, refclock div to 2. */ 149 ub_setreg(IMX_UFCR, 0x00004210); 150 } 151 152 static void 153 uart_cnputc(struct consdev *cp, int c) 154 { 155 156 ub_putc(c); 157 } 158 159 static int 160 uart_cngetc(struct consdev * cp) 161 { 162 163 return ub_getc(); 164 } 165 166 static void 167 uart_cnterm(struct consdev * cp) 168 { 169 170 } 171 172 CONSOLE_DRIVER(uart); 173