#ifndef __DEBUG_LL_NS16550_H #define __DEBUG_LL_NS16550_H /* * Early debugging functions for the NS16550 * This file needs register access functions declared as: * * uint8_t debug_ll_read_reg(int reg); * void debug_ll_write_reg(int reg, uint8_t val); */ #define NS16550_THR 0x0 #define NS16550_RBR 0x0 #define NS16550_DLL 0x0 #define NS16550_IER 0x1 #define NS16550_DLM 0x1 #define NS16550_FCR 0x2 #define NS16550_LCR 0x3 #define NS16550_MCR 0x4 #define NS16550_LSR 0x5 #define NS16550_LCR_VAL 0x3 /* 8 data, 1 stop, no parity */ #define NS16550_MCR_VAL 0x3 /* RTS/DTR */ #define NS16550_FCR_VAL 0x7 /* Clear & enable FIFOs */ #define NS16550_LSR_DR 0x01 /* UART received data present */ #define NS16550_LSR_THRE 0x20 /* Xmit holding register empty */ #define NS16550_LCR_BKSE 0x80 /* Bank select enable */ static inline void PUTC_LL(char ch) { while (!(debug_ll_read_reg(NS16550_LSR) & NS16550_LSR_THRE)) ; debug_ll_write_reg(NS16550_THR, ch); } static inline uint16_t debug_ll_ns16550_calc_divisor(unsigned long clk) { return clk / (115200 * 16); } static inline void debug_ll_ns16550_init(uint16_t divisor) { debug_ll_write_reg(NS16550_LCR, 0x0); /* select ier reg */ debug_ll_write_reg(0x00, NS16550_IER); debug_ll_write_reg(NS16550_LCR, NS16550_LCR_BKSE); debug_ll_write_reg(NS16550_DLL, divisor & 0xff); debug_ll_write_reg(NS16550_DLM, (divisor >> 8) & 0xff); debug_ll_write_reg(NS16550_LCR, NS16550_LCR_VAL); debug_ll_write_reg(NS16550_MCR, NS16550_MCR_VAL); debug_ll_write_reg(NS16550_FCR, NS16550_FCR_VAL); } #endif