arch/mips/boot/compressed/uart-16550.c

   1 /*
   2  * 16550 compatible uart based serial debug support for zboot
   3  */
   4
   5 #include <linux/types.h>
   6 #include <linux/serial_reg.h>
   7
   8 #include <asm/addrspace.h>
   9
  10 #if defined(CONFIG_MACH_LOONGSON64) || defined(CONFIG_MIPS_MALTA)
  11 #define UART_BASE 0x1fd003f8
  12 #define PORT(offset) (CKSEG1ADDR(UART_BASE) + (offset))
  13 #endif
  14
  15 #ifdef CONFIG_AR7
  16 #include <ar7.h>
  17 #define PORT(offset) (CKSEG1ADDR(AR7_REGS_UART0) + (4 * offset))
  18 #endif
  19
  20 #ifdef CONFIG_MACH_JZ4740
  21 #include <asm/mach-jz4740/base.h>
  22 #define PORT(offset) (CKSEG1ADDR(JZ4740_UART0_BASE_ADDR) + (4 * offset))
  23 #endif
  24
  25 #ifdef CONFIG_CPU_XLR
  26 #define UART0_BASE  0x1EF14000
  27 #define PORT(offset) (CKSEG1ADDR(UART0_BASE) + (4 * offset))
  28 #define IOTYPE unsigned int
  29 #endif
  30
  31 #ifdef CONFIG_CPU_XLP
  32 #define UART0_BASE  0x18030100
  33 #define PORT(offset) (CKSEG1ADDR(UART0_BASE) + (4 * offset))
  34 #define IOTYPE unsigned int
  35 #endif
  36
  37 #ifndef IOTYPE
  38 #define IOTYPE char
  39 #endif
  40
  41 #ifndef PORT
  42 #error please define the serial port address for your own machine
  43 #endif
  44
  45 static inline unsigned int serial_in(int offset)
  46 {
  47         return *((volatile IOTYPE *)PORT(offset)) & 0xFF;
  48 }
  49
  50 static inline void serial_out(int offset, int value)
  51 {
  52         *((volatile IOTYPE *)PORT(offset)) = value & 0xFF;
  53 }
  54
  55 void putc(char c)
  56 {
  57         int timeout = 1000000;
  58
  59         while (((serial_in(UART_LSR) & UART_LSR_THRE) == 0) && (timeout-- > 0))
  60                 ;
  61
  62         serial_out(UART_TX, c);
  63 }