include/asm-xen/asm-x86_64/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 #include <linux/vmalloc.h>
  30
  31 /* XEN: Hit DMA paths on the head. This trick from asm-m68k/floppy.h. */
  32 #include <asm/dma.h>
  33 #undef MAX_DMA_ADDRESS
  34 #define MAX_DMA_ADDRESS 0
  35 #define CROSS_64KB(a,s) (0)
  36
  37 #define fd_inb(port)                    inb_p(port)
  38 #define fd_outb(value,port)             outb_p(value,port)
  39
  40 #define fd_request_dma()        (0)
  41 #define fd_free_dma()           ((void)0)
  42 #define fd_enable_irq()         enable_irq(FLOPPY_IRQ)
  43 #define fd_disable_irq()        disable_irq(FLOPPY_IRQ)
  44 #define fd_free_irq()           free_irq(FLOPPY_IRQ, NULL)
  45 #define fd_get_dma_residue()    vdma_get_dma_residue(FLOPPY_DMA)
  46 #define fd_dma_mem_alloc(size)  vdma_mem_alloc(size)
  47 #define fd_dma_mem_free(addr, size) vdma_mem_free(addr, size)
  48 #define fd_dma_setup(addr, size, mode, io) vdma_dma_setup(addr, size, mode, io)
  49
  50 static int virtual_dma_count;
  51 static int virtual_dma_residue;
  52 static char *virtual_dma_addr;
  53 static int virtual_dma_mode;
  54 static int doing_pdma;
  55
  56 static irqreturn_t floppy_hardint(int irq, void *dev_id, struct pt_regs * regs)
  57 {
  58         register unsigned char st;
  59
  60 #undef TRACE_FLPY_INT
  61
  62 #ifdef TRACE_FLPY_INT
  63         static int calls=0;
  64         static int bytes=0;
  65         static int dma_wait=0;
  66 #endif
  67         if (!doing_pdma)
  68                 return floppy_interrupt(irq, dev_id, regs);
  69
  70 #ifdef TRACE_FLPY_INT
  71         if(!calls)
  72                 bytes = virtual_dma_count;
  73 #endif
  74
  75         {
  76                 register int lcount;
  77                 register char *lptr;
  78
  79                 st = 1;
  80                 for(lcount=virtual_dma_count, lptr=virtual_dma_addr;
  81                     lcount; lcount--, lptr++) {
  82                         st=inb(virtual_dma_port+4) & 0xa0 ;
  83                         if(st != 0xa0)
  84                                 break;
  85                         if(virtual_dma_mode)
  86                                 outb_p(*lptr, virtual_dma_port+5);
  87                         else
  88                                 *lptr = inb_p(virtual_dma_port+5);
  89                 }
  90                 virtual_dma_count = lcount;
  91                 virtual_dma_addr = lptr;
  92                 st = inb(virtual_dma_port+4);
  93         }
  94
  95 #ifdef TRACE_FLPY_INT
  96         calls++;
  97 #endif
  98         if(st == 0x20)
  99                 return IRQ_HANDLED;
 100         if(!(st & 0x20)) {
 101                 virtual_dma_residue += virtual_dma_count;
 102                 virtual_dma_count=0;
 103 #ifdef TRACE_FLPY_INT
 104                 printk("count=%x, residue=%x calls=%d bytes=%d dma_wait=%d\n",
 105                        virtual_dma_count, virtual_dma_residue, calls, bytes,
 106                        dma_wait);
 107                 calls = 0;
 108                 dma_wait=0;
 109 #endif
 110                 doing_pdma = 0;
 111                 floppy_interrupt(irq, dev_id, regs);
 112                 return IRQ_HANDLED;
 113         }
 114 #ifdef TRACE_FLPY_INT
 115         if(!virtual_dma_count)
 116                 dma_wait++;
 117 #endif
 118         return IRQ_HANDLED;
 119 }
 120
 121 static void fd_disable_dma(void)
 122 {
 123         doing_pdma = 0;
 124         virtual_dma_residue += virtual_dma_count;
 125         virtual_dma_count=0;
 126 }
 127
 128 static int vdma_get_dma_residue(unsigned int dummy)
 129 {
 130         return virtual_dma_count + virtual_dma_residue;
 131 }
 132
 133
 134 static int fd_request_irq(void)
 135 {
 136         return request_irq(FLOPPY_IRQ, floppy_hardint,SA_INTERRUPT,
 137                                            "floppy", NULL);
 138 }
 139
 140
 141 static unsigned long vdma_mem_alloc(unsigned long size)
 142 {
 143         return (unsigned long) vmalloc(size);
 144
 145 }
 146
 147 static void vdma_mem_free(unsigned long addr, unsigned long size)
 148 {
 149         vfree((void *)addr);
 150 }
 151
 152 static int vdma_dma_setup(char *addr, unsigned long size, int mode, int io)
 153 {
 154         doing_pdma = 1;
 155         virtual_dma_port = io;
 156         virtual_dma_mode = (mode  == DMA_MODE_WRITE);
 157         virtual_dma_addr = addr;
 158         virtual_dma_count = size;
 159         virtual_dma_residue = 0;
 160         return 0;
 161 }
 162
 163 /* XEN: This trick to force 'virtual DMA' is from include/asm-m68k/floppy.h. */
 164 #define FDC1 xen_floppy_init()
 165 static int FDC2 = -1;
 166
 167 static int xen_floppy_init(void)
 168 {
 169         use_virtual_dma = 1;
 170         can_use_virtual_dma = 1;
 171         return 0x340;
 172 }
 173
 174 /*
 175  * Floppy types are stored in the rtc's CMOS RAM and so rtc_lock
 176  * is needed to prevent corrupted CMOS RAM in case "insmod floppy"
 177  * coincides with another rtc CMOS user.                Paul G.
 178  */
 179 #define FLOPPY0_TYPE    ({                              \
 180         unsigned long flags;                            \
 181         unsigned char val;                              \
 182         spin_lock_irqsave(&rtc_lock, flags);            \
 183         val = (CMOS_READ(0x10) >> 4) & 15;              \
 184         spin_unlock_irqrestore(&rtc_lock, flags);       \
 185         val;                                            \
 186 })
 187
 188 #define FLOPPY1_TYPE    ({                              \
 189         unsigned long flags;                            \
 190         unsigned char val;                              \
 191         spin_lock_irqsave(&rtc_lock, flags);            \
 192         val = CMOS_READ(0x10) & 15;                     \
 193         spin_unlock_irqrestore(&rtc_lock, flags);       \
 194         val;                                            \
 195 })
 196
 197 #define N_FDC 2
 198 #define N_DRIVE 8
 199
 200 #define FLOPPY_MOTOR_MASK 0xf0
 201
 202 #define EXTRA_FLOPPY_PARAMS
 203
 204 #endif /* __ASM_XEN_X86_64_FLOPPY_H */