1 /* 2 * COM1 NS16550 support 3 * originally from linux source (arch/ppc/boot/ns16550.c) 4 * modified to use CONFIG_SYS_ISA_MEM and new defines 5 */ 6 7 #include <config.h> 8 9 #ifdef CONFIG_SYS_NS16550 10 11 #include <ns16550.h> 12 13 #define LCRVAL LCR_8N1 /* 8 data, 1 stop, no parity */ 14 #define MCRVAL (MCR_DTR | MCR_RTS) /* RTS/DTR */ 15 #define FCRVAL (FCR_FIFO_EN | FCR_RXSR | FCR_TXSR) /* Clear & enable FIFOs */ 16 17 void NS16550_init (NS16550_t com_port, int baud_divisor) 18 { 19 com_port->ier = 0x00; 20 #ifdef CONFIG_OMAP 21 com_port->mdr1 = 0x7; /* mode select reset TL16C750*/ 22 #endif 23 com_port->lcr = LCR_BKSE | LCRVAL; 24 com_port->dll = 0; 25 com_port->dlm = 0; 26 com_port->lcr = LCRVAL; 27 com_port->mcr = MCRVAL; 28 com_port->fcr = FCRVAL; 29 com_port->lcr = LCR_BKSE | LCRVAL; 30 com_port->dll = baud_divisor & 0xff; 31 com_port->dlm = (baud_divisor >> 8) & 0xff; 32 com_port->lcr = LCRVAL; 33 #if defined(CONFIG_OMAP) 34 #if defined(CONFIG_APTIX) 35 com_port->mdr1 = 3; /* /13 mode so Aptix 6MHz can hit 115200 */ 36 #else 37 com_port->mdr1 = 0; /* /16 is proper to hit 115200 with 48MHz */ 38 #endif 39 #endif 40 } 41 42 void NS16550_reinit (NS16550_t com_port, int baud_divisor) 43 { 44 com_port->ier = 0x00; 45 com_port->lcr = LCR_BKSE | LCRVAL; 46 com_port->dll = 0; 47 com_port->dlm = 0; 48 com_port->lcr = LCRVAL; 49 com_port->mcr = MCRVAL; 50 com_port->fcr = FCRVAL; 51 com_port->lcr = LCR_BKSE; 52 com_port->dll = baud_divisor & 0xff; 53 com_port->dlm = (baud_divisor >> 8) & 0xff; 54 com_port->lcr = LCRVAL; 55 } 56 57 void NS16550_putc (NS16550_t com_port, char c) 58 { 59 while ((com_port->lsr & LSR_THRE) == 0); 60 com_port->thr = c; 61 } 62 63 char NS16550_getc (NS16550_t com_port) 64 { 65 while ((com_port->lsr & LSR_DR) == 0) { 66 #ifdef CONFIG_USB_TTY 67 extern void usbtty_poll(void); 68 usbtty_poll(); 69 #endif 70 } 71 return (com_port->rbr); 72 } 73 74 int NS16550_tstc (NS16550_t com_port) 75 { 76 return ((com_port->lsr & LSR_DR) != 0); 77 } 78 79 #endif 80