1 /* 2 * COM1 NS16550 support 3 * originally from linux source (arch/powerpc/boot/ns16550.c) 4 * modified to use CONFIG_SYS_ISA_MEM and new defines 5 */ 6 7 #include <config.h> 8 #include <ns16550.h> 9 #include <watchdog.h> 10 #include <linux/types.h> 11 #include <asm/io.h> 12 13 #define UART_LCRVAL UART_LCR_8N1 /* 8 data, 1 stop, no parity */ 14 #define UART_MCRVAL (UART_MCR_DTR | \ 15 UART_MCR_RTS) /* RTS/DTR */ 16 #define UART_FCRVAL (UART_FCR_FIFO_EN | \ 17 UART_FCR_RXSR | \ 18 UART_FCR_TXSR) /* Clear & enable FIFOs */ 19 #ifdef CONFIG_SYS_NS16550_PORT_MAPPED 20 #define serial_out(x, y) outb(x, (ulong)y) 21 #define serial_in(y) inb((ulong)y) 22 #elif defined(CONFIG_SYS_NS16550_MEM32) && (CONFIG_SYS_NS16550_REG_SIZE > 0) 23 #define serial_out(x, y) out_be32(y, x) 24 #define serial_in(y) in_be32(y) 25 #elif defined(CONFIG_SYS_NS16550_MEM32) && (CONFIG_SYS_NS16550_REG_SIZE < 0) 26 #define serial_out(x, y) out_le32(y, x) 27 #define serial_in(y) in_le32(y) 28 #else 29 #define serial_out(x, y) writeb(x, y) 30 #define serial_in(y) readb(y) 31 #endif 32 33 #ifndef CONFIG_SYS_NS16550_IER 34 #define CONFIG_SYS_NS16550_IER 0x00 35 #endif /* CONFIG_SYS_NS16550_IER */ 36 37 void NS16550_init(NS16550_t com_port, int baud_divisor) 38 { 39 #if (defined(CONFIG_SPL_BUILD) && defined(CONFIG_OMAP34XX)) 40 /* 41 * On some OMAP3 devices when UART3 is configured for boot mode before 42 * SPL starts only THRE bit is set. We have to empty the transmitter 43 * before initialization starts. 44 */ 45 if ((serial_in(&com_port->lsr) & (UART_LSR_TEMT | UART_LSR_THRE)) 46 == UART_LSR_THRE) { 47 serial_out(UART_LCR_DLAB, &com_port->lcr); 48 serial_out(baud_divisor & 0xff, &com_port->dll); 49 serial_out((baud_divisor >> 8) & 0xff, &com_port->dlm); 50 serial_out(UART_LCRVAL, &com_port->lcr); 51 serial_out(0, &com_port->mdr1); 52 } 53 #endif 54 55 while (!(serial_in(&com_port->lsr) & UART_LSR_TEMT)) 56 ; 57 58 serial_out(CONFIG_SYS_NS16550_IER, &com_port->ier); 59 #if (defined(CONFIG_OMAP) && !defined(CONFIG_OMAP3_ZOOM2)) || \ 60 defined(CONFIG_AM33XX) || defined(CONFIG_TI814X) 61 serial_out(0x7, &com_port->mdr1); /* mode select reset TL16C750*/ 62 #endif 63 serial_out(UART_LCR_BKSE | UART_LCRVAL, &com_port->lcr); 64 serial_out(0, &com_port->dll); 65 serial_out(0, &com_port->dlm); 66 serial_out(UART_LCRVAL, &com_port->lcr); 67 serial_out(UART_MCRVAL, &com_port->mcr); 68 serial_out(UART_FCRVAL, &com_port->fcr); 69 serial_out(UART_LCR_BKSE | UART_LCRVAL, &com_port->lcr); 70 serial_out(baud_divisor & 0xff, &com_port->dll); 71 serial_out((baud_divisor >> 8) & 0xff, &com_port->dlm); 72 serial_out(UART_LCRVAL, &com_port->lcr); 73 #if (defined(CONFIG_OMAP) && !defined(CONFIG_OMAP3_ZOOM2)) || \ 74 defined(CONFIG_AM33XX) || defined(CONFIG_SOC_DA8XX) || \ 75 defined(CONFIG_TI814X) 76 77 #if defined(CONFIG_APTIX) 78 /* /13 mode so Aptix 6MHz can hit 115200 */ 79 serial_out(3, &com_port->mdr1); 80 #else 81 /* /16 is proper to hit 115200 with 48MHz */ 82 serial_out(0, &com_port->mdr1); 83 #endif 84 #endif /* CONFIG_OMAP */ 85 } 86 87 #ifndef CONFIG_NS16550_MIN_FUNCTIONS 88 void NS16550_reinit(NS16550_t com_port, int baud_divisor) 89 { 90 serial_out(CONFIG_SYS_NS16550_IER, &com_port->ier); 91 serial_out(UART_LCR_BKSE | UART_LCRVAL, &com_port->lcr); 92 serial_out(0, &com_port->dll); 93 serial_out(0, &com_port->dlm); 94 serial_out(UART_LCRVAL, &com_port->lcr); 95 serial_out(UART_MCRVAL, &com_port->mcr); 96 serial_out(UART_FCRVAL, &com_port->fcr); 97 serial_out(UART_LCR_BKSE, &com_port->lcr); 98 serial_out(baud_divisor & 0xff, &com_port->dll); 99 serial_out((baud_divisor >> 8) & 0xff, &com_port->dlm); 100 serial_out(UART_LCRVAL, &com_port->lcr); 101 } 102 #endif /* CONFIG_NS16550_MIN_FUNCTIONS */ 103 104 void NS16550_putc(NS16550_t com_port, char c) 105 { 106 while ((serial_in(&com_port->lsr) & UART_LSR_THRE) == 0) 107 ; 108 serial_out(c, &com_port->thr); 109 110 /* 111 * Call watchdog_reset() upon newline. This is done here in putc 112 * since the environment code uses a single puts() to print the complete 113 * environment upon "printenv". So we can't put this watchdog call 114 * in puts(). 115 */ 116 if (c == '\n') 117 WATCHDOG_RESET(); 118 } 119 120 #ifndef CONFIG_NS16550_MIN_FUNCTIONS 121 char NS16550_getc(NS16550_t com_port) 122 { 123 while ((serial_in(&com_port->lsr) & UART_LSR_DR) == 0) { 124 #if !defined(CONFIG_SPL_BUILD) && defined(CONFIG_USB_TTY) 125 extern void usbtty_poll(void); 126 usbtty_poll(); 127 #endif 128 WATCHDOG_RESET(); 129 } 130 return serial_in(&com_port->rbr); 131 } 132 133 int NS16550_tstc(NS16550_t com_port) 134 { 135 return (serial_in(&com_port->lsr) & UART_LSR_DR) != 0; 136 } 137 138 #endif /* CONFIG_NS16550_MIN_FUNCTIONS */ 139