arch/arm/mach-davinci/include/mach/debug-macro.S

   1 /*
   2  * Debugging macro for DaVinci
   3  *
   4  * Author: Kevin Hilman, MontaVista Software, Inc. <source@mvista.com>
   5  *
   6  * 2007 (c) MontaVista Software, Inc. This file is licensed under
   7  * the terms of the GNU General Public License version 2. This program
   8  * is licensed "as is" without any warranty of any kind, whether express
   9  * or implied.
  10  */
  11
  12 /* Modifications
  13  * Jan 2009     Chaithrika U S  Added senduart, busyuart, waituart
  14  *                              macros, based on debug-8250.S file
  15  *                              but using 32-bit accesses required for
  16  *                              some davinci devices.
  17  */
  18
  19 #include <linux/serial_reg.h>
  20
  21 #include <asm/memory.h>
  22
  23 #include <mach/serial.h>
  24
  25 #define UART_SHIFT      2
  26
  27 #define davinci_uart_v2p(x)     ((x) - PAGE_OFFSET + PLAT_PHYS_OFFSET)
  28 #define davinci_uart_p2v(x)     ((x) - PLAT_PHYS_OFFSET + PAGE_OFFSET)
  29
  30                 .pushsection .data
  31 davinci_uart_phys:      .word   0
  32 davinci_uart_virt:      .word   0
  33                 .popsection
  34
  35                 .macro addruart, rp, rv
  36
  37                 /* Use davinci_uart_phys/virt if already configured */
  38 10:             mrc     p15, 0, \rp, c1, c0
  39                 tst     \rp, #1                 @ MMU enabled?
  40                 ldreq   \rp, =davinci_uart_v2p(davinci_uart_phys)
  41                 ldrne   \rp, =davinci_uart_phys
  42                 add     \rv, \rp, #4            @ davinci_uart_virt
  43                 ldr     \rp, [\rp, #0]
  44                 ldr     \rv, [\rv, #0]
  45                 cmp     \rp, #0                 @ is port configured?
  46                 cmpne   \rv, #0
  47                 bne     99f                     @ already configured
  48
  49                 /* Check the debug UART address set in uncompress.h */
  50                 mrc     p15, 0, \rp, c1, c0
  51                 tst     \rp, #1                 @ MMU enabled?
  52
  53                 /* Copy uart phys address from decompressor uart info */
  54                 ldreq   \rv, =davinci_uart_v2p(davinci_uart_phys)
  55                 ldrne   \rv, =davinci_uart_phys
  56                 ldreq   \rp, =DAVINCI_UART_INFO
  57                 ldrne   \rp, =davinci_uart_p2v(DAVINCI_UART_INFO)
  58                 ldr     \rp, [\rp, #0]
  59                 str     \rp, [\rv]
  60
  61                 /* Copy uart virt address from decompressor uart info */
  62                 ldreq   \rv, =davinci_uart_v2p(davinci_uart_virt)
  63                 ldrne   \rv, =davinci_uart_virt
  64                 ldreq   \rp, =DAVINCI_UART_INFO
  65                 ldrne   \rp, =davinci_uart_p2v(DAVINCI_UART_INFO)
  66                 ldr     \rp, [\rp, #4]
  67                 str     \rp, [\rv]
  68
  69                 b       10b
  70 99:
  71                 .endm
  72
  73                 .macro  senduart,rd,rx
  74                 str     \rd, [\rx, #UART_TX << UART_SHIFT]
  75                 .endm
  76
  77                 .macro  busyuart,rd,rx
  78 1002:           ldr     \rd, [\rx, #UART_LSR << UART_SHIFT]
  79                 and     \rd, \rd, #UART_LSR_TEMT | UART_LSR_THRE
  80                 teq     \rd, #UART_LSR_TEMT | UART_LSR_THRE
  81                 bne     1002b
  82                 .endm
  83
  84                 .macro  waituart,rd,rx
  85 #ifdef FLOW_CONTROL
  86 1001:           ldr     \rd, [\rx, #UART_MSR << UART_SHIFT]
  87                 tst     \rd, #UART_MSR_CTS
  88                 beq     1001b
  89 #endif
  90                 .endm
  91