xref: /openbmc/linux/arch/mips/boot/compressed/uart-16550.c (revision 03ab8e6297acd1bc0eedaa050e2a1635c576fd11)
1b2441318SGreg Kroah-Hartman // SPDX-License-Identifier: GPL-2.0
21b93b3c3SWu Zhangjin /*
31b93b3c3SWu Zhangjin  * 16550 compatible uart based serial debug support for zboot
41b93b3c3SWu Zhangjin  */
51b93b3c3SWu Zhangjin 
61b93b3c3SWu Zhangjin #include <linux/types.h>
71b93b3c3SWu Zhangjin #include <linux/serial_reg.h>
81b93b3c3SWu Zhangjin 
91b93b3c3SWu Zhangjin #include <asm/addrspace.h>
101b93b3c3SWu Zhangjin 
1130ad29bbSHuacai Chen #if defined(CONFIG_MACH_LOONGSON64) || defined(CONFIG_MIPS_MALTA)
121b93b3c3SWu Zhangjin #define UART_BASE 0x1fd003f8
131b93b3c3SWu Zhangjin #define PORT(offset) (CKSEG1ADDR(UART_BASE) + (offset))
141b93b3c3SWu Zhangjin #endif
151b93b3c3SWu Zhangjin 
161b93b3c3SWu Zhangjin #ifdef CONFIG_AR7
171b93b3c3SWu Zhangjin #include <ar7.h>
181b93b3c3SWu Zhangjin #define PORT(offset) (CKSEG1ADDR(AR7_REGS_UART0) + (4 * offset))
191b93b3c3SWu Zhangjin #endif
201b93b3c3SWu Zhangjin 
21c60128ceSPaul Cercueil #ifdef CONFIG_MACH_INGENIC
22*f92a05b9SPaul Cercueil #define INGENIC_UART_BASE_ADDR	(0x10030000 + 0x1000 * CONFIG_ZBOOT_INGENIC_UART)
23*f92a05b9SPaul Cercueil #define PORT(offset) (CKSEG1ADDR(INGENIC_UART_BASE_ADDR) + (4 * offset))
24f9c9affcSLluís Batlle i Rossell #endif
25f9c9affcSLluís Batlle i Rossell 
26d6a50784SJayachandran C #ifndef IOTYPE
27d6a50784SJayachandran C #define IOTYPE char
28d6a50784SJayachandran C #endif
29d6a50784SJayachandran C 
301b93b3c3SWu Zhangjin #ifndef PORT
311b93b3c3SWu Zhangjin #error please define the serial port address for your own machine
321b93b3c3SWu Zhangjin #endif
331b93b3c3SWu Zhangjin 
serial_in(int offset)341b93b3c3SWu Zhangjin static inline unsigned int serial_in(int offset)
351b93b3c3SWu Zhangjin {
36d6a50784SJayachandran C 	return *((volatile IOTYPE *)PORT(offset)) & 0xFF;
371b93b3c3SWu Zhangjin }
381b93b3c3SWu Zhangjin 
serial_out(int offset,int value)391b93b3c3SWu Zhangjin static inline void serial_out(int offset, int value)
401b93b3c3SWu Zhangjin {
41d6a50784SJayachandran C 	*((volatile IOTYPE *)PORT(offset)) = value & 0xFF;
421b93b3c3SWu Zhangjin }
431b93b3c3SWu Zhangjin 
putc(char c)441b93b3c3SWu Zhangjin void putc(char c)
451b93b3c3SWu Zhangjin {
46d6a50784SJayachandran C 	int timeout = 1000000;
471b93b3c3SWu Zhangjin 
481b93b3c3SWu Zhangjin 	while (((serial_in(UART_LSR) & UART_LSR_THRE) == 0) && (timeout-- > 0))
491b93b3c3SWu Zhangjin 		;
501b93b3c3SWu Zhangjin 
511b93b3c3SWu Zhangjin 	serial_out(UART_TX, c);
521b93b3c3SWu Zhangjin }
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