kernel/arch/arm/include/debug/8250.S

   1 /*
   2  * arch/arm/include/debug/8250.S
   3  *
   4  *  Copyright (C) 1994-2013 Russell King
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  */
  10 #include <linux/serial_reg.h>
  11
  12                 .macro  addruart, rp, rv, tmp
  13                 ldr     \rp, =CONFIG_DEBUG_UART_PHYS
  14                 ldr     \rv, =CONFIG_DEBUG_UART_VIRT
  15                 .endm
  16
  17 #ifdef CONFIG_DEBUG_UART_8250_WORD
  18                 .macro  store, rd, rx:vararg
  19                 str     \rd, \rx
  20                 .endm
  21
  22                 .macro  load, rd, rx:vararg
  23                 ldr     \rd, \rx
  24                 .endm
  25 #else
  26                 .macro  store, rd, rx:vararg
  27                 strb    \rd, \rx
  28                 .endm
  29
  30                 .macro  load, rd, rx:vararg
  31                 ldrb    \rd, \rx
  32                 .endm
  33 #endif
  34
  35 #define UART_SHIFT CONFIG_DEBUG_UART_8250_SHIFT
  36
  37                 .macro  senduart,rd,rx
  38                 store   \rd, [\rx, #UART_TX << UART_SHIFT]
  39                 .endm
  40
  41                 .macro  busyuart,rd,rx
  42 1002:           load    \rd, [\rx, #UART_LSR << UART_SHIFT]
  43                 and     \rd, \rd, #UART_LSR_TEMT | UART_LSR_THRE
  44                 teq     \rd, #UART_LSR_TEMT | UART_LSR_THRE
  45                 bne     1002b
  46                 .endm
  47
  48                 .macro  waituart,rd,rx
  49 #ifdef CONFIG_DEBUG_UART_8250_FLOW_CONTROL
  50 1001:           load    \rd, [\rx, #UART_MSR << UART_SHIFT]
  51                 tst     \rd, #UART_MSR_CTS
  52                 beq     1001b
  53 #endif
  54                 .endm