root/arch/arm/include/debug/imx.S

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /* arch/arm/mach-imx/include/mach/debug-macro.S
   3  *
   4  * Debugging macro include header
   5  *
   6  *  Copyright (C) 1994-1999 Russell King
   7  *  Moved from linux/arch/arm/kernel/debug.S by Ben Dooks
   8  */
   9 
  10 #include <asm/assembler.h>
  11 #include "imx-uart.h"
  12 
  13 /*
  14  * FIXME: This is a copy of IMX_IO_P2V in hardware.h, and needs to
  15  * stay sync with that.  It's hard to maintain, and should be fixed
  16  * globally for multi-platform build to use a fixed virtual address
  17  * for low-level debug uart port across platforms.
  18  */
  19 #define IMX_IO_P2V(x)   (                                               \
  20                         (((x) & 0x80000000) >> 7) |                     \
  21                         (0xf4000000 +                                   \
  22                         (((x) & 0x50000000) >> 6) +                     \
  23                         (((x) & 0x0b000000) >> 4) +                     \
  24                         (((x) & 0x000fffff))))
  25 
  26 #define UART_VADDR      IMX_IO_P2V(UART_PADDR)
  27 
  28                 .macro  addruart, rp, rv, tmp
  29                 ldr     \rp, =UART_PADDR        @ physical
  30                 ldr     \rv, =UART_VADDR        @ virtual
  31                 .endm
  32 
  33                 .macro  senduart,rd,rx
  34                 ARM_BE8(rev \rd, \rd)
  35                 str     \rd, [\rx, #0x40]       @ TXDATA
  36                 .endm
  37 
  38                 .macro  waituart,rd,rx
  39                 .endm
  40 
  41                 .macro  busyuart,rd,rx
  42 1002:           ldr     \rd, [\rx, #0x98]       @ SR2
  43                 ARM_BE8(rev \rd, \rd)
  44                 tst     \rd, #1 << 3            @ TXDC
  45                 beq     1002b                   @ wait until transmit done
  46                 .endm