target/linux/oxnas/files/arch/arm/mach-oxnas/fiq.S

   1 /*
   2  *  Copyright (C) 2012 Gateworks Corporation
   3  *      Chris Lang <clang@gateworks.com>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License version 2 as
   7  * published by the Free Software Foundation.
   8  */
   9 #include <linux/linkage.h>
  10 #include <asm/assembler.h>
  11 #include <asm/asm-offsets.h>
  12
  13 #define D_CACHE_LINE_SIZE 32
  14
  15         .text
  16
  17 /*
  18  * R8  - DMA Start Address
  19  * R9  - DMA Length
  20  * R10 - DMA Direction
  21  * R11 - DMA type
  22  * R12 - fiq_buffer Address
  23 */
  24
  25         .global ox820_fiq_end
  26 ENTRY(ox820_fiq_start)
  27         str     r8, [r13]
  28
  29         ldmia   r12, {r8, r9, r10}
  30         and     r11, r10, #0x3000000
  31         and     r10, r10, #0xff
  32
  33         teq     r11, #0x1000000
  34         beq     ox820_dma_map_area
  35         teq     r11, #0x2000000
  36         beq     ox820_dma_unmap_area
  37         /* fall through */
  38 ox820_dma_flush_range:
  39         bic     r8, r8, #D_CACHE_LINE_SIZE - 1
  40 1:
  41         mcr     p15, 0, r8, c7, c14, 1          @ clean & invalidate D line
  42         add     r8, r8, #D_CACHE_LINE_SIZE
  43         cmp     r8, r9
  44         blo     1b
  45         /* fall through */
  46 ox820_fiq_exit:
  47         mov     r8, #0
  48         str     r8, [r12, #8]
  49         mcr     p15, 0, r8, c7, c10, 4          @ drain write buffer
  50         subs    pc, lr, #4
  51
  52 ox820_dma_map_area:
  53         add     r9, r9, r8
  54         teq     r10, #DMA_FROM_DEVICE
  55         beq     ox820_dma_inv_range
  56         teq     r10, #DMA_TO_DEVICE
  57         bne     ox820_dma_flush_range
  58         /* fall through */
  59 ox820_dma_clean_range:
  60         bic     r8, r8, #D_CACHE_LINE_SIZE - 1
  61 1:
  62         mcr     p15, 0, r8, c7, c10, 1          @ clean D line
  63         add     r8, r8, #D_CACHE_LINE_SIZE
  64         cmp     r8, r9
  65         blo     1b
  66         b       ox820_fiq_exit
  67
  68 ox820_dma_unmap_area:
  69         add     r9, r9, r8
  70         teq     r10, #DMA_TO_DEVICE
  71         beq     ox820_fiq_exit
  72         /* fall through */
  73 ox820_dma_inv_range:
  74         tst     r8, #D_CACHE_LINE_SIZE - 1
  75         bic     r8, r8, #D_CACHE_LINE_SIZE - 1
  76         mcrne   p15, 0, r8, c7, c10, 1          @ clean D line
  77         tst     r9, #D_CACHE_LINE_SIZE - 1
  78         bic     r9, r9, #D_CACHE_LINE_SIZE - 1
  79         mcrne   p15, 0, r9, c7, c14, 1          @ clean & invalidate D line
  80 1:
  81         mcr     p15, 0, r8, c7, c6, 1           @ invalidate D line
  82         add     r8, r8, #D_CACHE_LINE_SIZE
  83         cmp     r8, r9
  84         blo     1b
  85         b       ox820_fiq_exit
  86
  87 ox820_fiq_end: