root/arch/arm/include/debug/sa1100.S

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /* arch/arm/include/debug/sa1100.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 #define UTCR3           0x0c
  11 #define UTDR            0x14
  12 #define UTSR1           0x20
  13 #define UTCR3_TXE       0x00000002      /* Transmit Enable                 */
  14 #define UTSR1_TBY       0x00000001      /* Transmitter BusY (read)         */
  15 #define UTSR1_TNF       0x00000004      /* Transmit FIFO Not Full (read)   */
  16 
  17                 .macro  addruart, rp, rv, tmp
  18                 mrc     p15, 0, \rp, c1, c0
  19                 tst     \rp, #1                 @ MMU enabled?
  20                 moveq   \rp, #0x80000000        @ physical base address
  21                 movne   \rp, #0xf8000000        @ virtual address
  22 
  23                 @ We probe for the active serial port here, coherently with
  24                 @ the comment in arch/arm/mach-sa1100/include/mach/uncompress.h.
  25                 @ We assume r1 can be clobbered.
  26 
  27                 @ see if Ser3 is active
  28                 add     \rp, \rp, #0x00050000
  29                 ldr     \rv, [\rp, #UTCR3]
  30                 tst     \rv, #UTCR3_TXE
  31 
  32                 @ if Ser3 is inactive, then try Ser1
  33                 addeq   \rp, \rp, #(0x00010000 - 0x00050000)
  34                 ldreq   \rv, [\rp, #UTCR3]
  35                 tsteq   \rv, #UTCR3_TXE
  36 
  37                 @ if Ser1 is inactive, then try Ser2
  38                 addeq   \rp, \rp, #(0x00030000 - 0x00010000)
  39                 ldreq   \rv, [\rp, #UTCR3]
  40                 tsteq   \rv, #UTCR3_TXE
  41 
  42                 @ clear top bits, and generate both phys and virt addresses
  43                 lsl     \rp, \rp, #8
  44                 lsr     \rp, \rp, #8
  45                 orr     \rv, \rp, #0xf8000000   @ virtual
  46                 orr     \rp, \rp, #0x80000000   @ physical
  47 
  48                 .endm
  49 
  50                 .macro  senduart,rd,rx
  51                 str     \rd, [\rx, #UTDR]
  52                 .endm
  53 
  54                 .macro  waituart,rd,rx
  55 1001:           ldr     \rd, [\rx, #UTSR1]
  56                 tst     \rd, #UTSR1_TNF
  57                 beq     1001b
  58                 .endm
  59 
  60                 .macro  busyuart,rd,rx
  61 1001:           ldr     \rd, [\rx, #UTSR1]
  62                 tst     \rd, #UTSR1_TBY
  63                 bne     1001b
  64                 .endm