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