include/asm-x86_64/mach-xen/asm/floppy.h

   1 /*
   2  * Architecture specific parts of the Floppy driver
   3  *
   4  * This file is subject to the terms and conditions of the GNU General Public
   5  * License.  See the file "COPYING" in the main directory of this archive
   6  * for more details.
   7  *
   8  * Copyright (C) 1995
   9  *
  10  * Modifications for Xen are Copyright (c) 2004, Keir Fraser.
  11  */
  12 #ifndef __ASM_XEN_X86_64_FLOPPY_H
  13 #define __ASM_XEN_X86_64_FLOPPY_H
  14
  15 #include <linux/vmalloc.h>
  16
  17
  18 /*
  19  * The DMA channel used by the floppy controller cannot access data at
  20  * addresses >= 16MB
  21  *
  22  * Went back to the 1MB limit, as some people had problems with the floppy
  23  * driver otherwise. It doesn't matter much for performance anyway, as most
  24  * floppy accesses go through the track buffer.
  25  */
  26 #define _CROSS_64KB(a,s,vdma) \
  27 (!(vdma) && ((unsigned long)(a)/K_64 != ((unsigned long)(a) + (s) - 1) / K_64))
  28
  29 /* XEN: Hit DMA paths on the head. This trick from asm-m68k/floppy.h. */
  30 #include <asm/dma.h>
  31 #undef MAX_DMA_ADDRESS
  32 #define MAX_DMA_ADDRESS 0
  33 #define CROSS_64KB(a,s) (0)
  34
  35 #define fd_inb(port)                    inb_p(port)
  36 #define fd_outb(value,port)             outb_p(value,port)
  37
  38 #define fd_request_dma()        (0)
  39 #define fd_free_dma()           ((void)0)
  40 #define fd_enable_irq()         enable_irq(FLOPPY_IRQ)
  41 #define fd_disable_irq()        disable_irq(FLOPPY_IRQ)
  42 #define fd_free_irq()           free_irq(FLOPPY_IRQ, NULL)
  43 #define fd_get_dma_residue()    vdma_get_dma_residue(FLOPPY_DMA)
  44 /*
  45  * Do not use vmalloc/vfree: floppy_release_irq_and_dma() gets called from
  46  * softirq context via motor_off_callback. A generic bug we happen to trigger.
  47  */
  48 #define fd_dma_mem_alloc(size)  __get_free_pages(GFP_KERNEL|__GFP_NORETRY, get_order(size))
  49 #define fd_dma_mem_free(addr, size) free_pages(addr, get_order(size))
  50 #define fd_dma_setup(addr, size, mode, io) vdma_dma_setup(addr, size, mode, io)
  51
  52 static int virtual_dma_count;
  53 static int virtual_dma_residue;
  54 static char *virtual_dma_addr;
  55 static int virtual_dma_mode;
  56 static int doing_pdma;
  57
  58 static irqreturn_t floppy_hardint(int irq, void *dev_id)
  59 {
  60         register unsigned char st;
  61
  62 #undef TRACE_FLPY_INT
  63
  64 #ifdef TRACE_FLPY_INT
  65         static int calls=0;
  66         static int bytes=0;
  67         static int dma_wait=0;
  68 #endif
  69         if (!doing_pdma)
  70                 return floppy_interrupt(irq, dev_id);
  71
  72 #ifdef TRACE_FLPY_INT
  73         if(!calls)
  74                 bytes = virtual_dma_count;
  75 #endif
  76
  77         {
  78                 register int lcount;
  79                 register char *lptr;
  80
  81                 st = 1;
  82                 for(lcount=virtual_dma_count, lptr=virtual_dma_addr;
  83                     lcount; lcount--, lptr++) {
  84                         st=inb(virtual_dma_port+4) & 0xa0 ;
  85                         if(st != 0xa0)
  86                                 break;
  87                         if(virtual_dma_mode)
  88                                 outb_p(*lptr, virtual_dma_port+5);
  89                         else
  90                                 *lptr = inb_p(virtual_dma_port+5);
  91                 }
  92                 virtual_dma_count = lcount;
  93                 virtual_dma_addr = lptr;
  94                 st = inb(virtual_dma_port+4);
  95         }
  96
  97 #ifdef TRACE_FLPY_INT
  98         calls++;
  99 #endif
 100         if(st == 0x20)
 101                 return IRQ_HANDLED;
 102         if(!(st & 0x20)) {
 103                 virtual_dma_residue += virtual_dma_count;
 104                 virtual_dma_count=0;
 105 #ifdef TRACE_FLPY_INT
 106                 printk("count=%x, residue=%x calls=%d bytes=%d dma_wait=%d\n",
 107                        virtual_dma_count, virtual_dma_residue, calls, bytes,
 108                        dma_wait);
 109                 calls = 0;
 110                 dma_wait=0;
 111 #endif
 112                 doing_pdma = 0;
 113                 floppy_interrupt(irq, dev_id);
 114                 return IRQ_HANDLED;
 115         }
 116 #ifdef TRACE_FLPY_INT
 117         if(!virtual_dma_count)
 118                 dma_wait++;
 119 #endif
 120         return IRQ_HANDLED;
 121 }
 122
 123 static void fd_disable_dma(void)
 124 {
 125         doing_pdma = 0;
 126         virtual_dma_residue += virtual_dma_count;
 127         virtual_dma_count=0;
 128 }
 129
 130 static int vdma_get_dma_residue(unsigned int dummy)
 131 {
 132         return virtual_dma_count + virtual_dma_residue;
 133 }
 134
 135
 136 static int fd_request_irq(void)
 137 {
 138         return request_irq(FLOPPY_IRQ, floppy_hardint,
 139                            IRQF_DISABLED, "floppy", NULL);
 140 }
 141
 142 #if 0
 143 static unsigned long vdma_mem_alloc(unsigned long size)
 144 {
 145         return (unsigned long) vmalloc(size);
 146
 147 }
 148
 149 static void vdma_mem_free(unsigned long addr, unsigned long size)
 150 {
 151         vfree((void *)addr);
 152 }
 153 #endif
 154
 155 static int vdma_dma_setup(char *addr, unsigned long size, int mode, int io)
 156 {
 157         doing_pdma = 1;
 158         virtual_dma_port = io;
 159         virtual_dma_mode = (mode  == DMA_MODE_WRITE);
 160         virtual_dma_addr = addr;
 161         virtual_dma_count = size;
 162         virtual_dma_residue = 0;
 163         return 0;
 164 }
 165
 166 /* XEN: This trick to force 'virtual DMA' is from include/asm-m68k/floppy.h. */
 167 #define FDC1 xen_floppy_init()
 168 static int FDC2 = -1;
 169
 170 static int xen_floppy_init(void)
 171 {
 172         use_virtual_dma = 1;
 173         can_use_virtual_dma = 1;
 174         return 0x3f0;
 175 }
 176
 177 /*
 178  * Floppy types are stored in the rtc's CMOS RAM and so rtc_lock
 179  * is needed to prevent corrupted CMOS RAM in case "insmod floppy"
 180  * coincides with another rtc CMOS user.                Paul G.
 181  */
 182 #define FLOPPY0_TYPE    ({                              \
 183         unsigned long flags;                            \
 184         unsigned char val;                              \
 185         spin_lock_irqsave(&rtc_lock, flags);            \
 186         val = (CMOS_READ(0x10) >> 4) & 15;              \
 187         spin_unlock_irqrestore(&rtc_lock, flags);       \
 188         val;                                            \
 189 })
 190
 191 #define FLOPPY1_TYPE    ({                              \
 192         unsigned long flags;                            \
 193         unsigned char val;                              \
 194         spin_lock_irqsave(&rtc_lock, flags);            \
 195         val = CMOS_READ(0x10) & 15;                     \
 196         spin_unlock_irqrestore(&rtc_lock, flags);       \
 197         val;                                            \
 198 })
 199
 200 #define N_FDC 2
 201 #define N_DRIVE 8
 202
 203 #define FLOPPY_MOTOR_MASK 0xf0
 204
 205 #define EXTRA_FLOPPY_PARAMS
 206
 207 #endif /* __ASM_XEN_X86_64_FLOPPY_H */