arch/x86/include/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 #ifndef _ASM_X86_FLOPPY_H
  11 #define _ASM_X86_FLOPPY_H
  12
  13 #include <linux/vmalloc.h>
  14
  15 /*
  16  * The DMA channel used by the floppy controller cannot access data at
  17  * addresses >= 16MB
  18  *
  19  * Went back to the 1MB limit, as some people had problems with the floppy
  20  * driver otherwise. It doesn't matter much for performance anyway, as most
  21  * floppy accesses go through the track buffer.
  22  */
  23 #define _CROSS_64KB(a, s, vdma)                                         \
  24         (!(vdma) &&                                                     \
  25          ((unsigned long)(a)/K_64 != ((unsigned long)(a) + (s) - 1) / K_64))
  26
  27 #define CROSS_64KB(a, s) _CROSS_64KB(a, s, use_virtual_dma & 1)
  28
  29
  30 #define SW fd_routine[use_virtual_dma & 1]
  31 #define CSW fd_routine[can_use_virtual_dma & 1]
  32
  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()        CSW._request_dma(FLOPPY_DMA, "floppy")
  38 #define fd_free_dma()           CSW._free_dma(FLOPPY_DMA)
  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()    SW._get_dma_residue(FLOPPY_DMA)
  43 #define fd_dma_mem_alloc(size)  SW._dma_mem_alloc(size)
  44 #define fd_dma_setup(addr, size, mode, io) SW._dma_setup(addr, size, mode, io)
  45
  46 #define FLOPPY_CAN_FALLBACK_ON_NODMA
  47
  48 static int virtual_dma_count;
  49 static int virtual_dma_residue;
  50 static char *virtual_dma_addr;
  51 static int virtual_dma_mode;
  52 static int doing_pdma;
  53
  54 static irqreturn_t floppy_hardint(int irq, void *dev_id)
  55 {
  56         unsigned char st;
  57
  58 #undef TRACE_FLPY_INT
  59
  60 #ifdef TRACE_FLPY_INT
  61         static int calls;
  62         static int bytes;
  63         static int dma_wait;
  64 #endif
  65         if (!doing_pdma)
  66                 return floppy_interrupt(irq, dev_id);
  67
  68 #ifdef TRACE_FLPY_INT
  69         if (!calls)
  70                 bytes = virtual_dma_count;
  71 #endif
  72
  73         {
  74                 int lcount;
  75                 char *lptr;
  76
  77                 st = 1;
  78                 for (lcount = virtual_dma_count, lptr = virtual_dma_addr;
  79                      lcount; lcount--, lptr++) {
  80                         st = inb(virtual_dma_port + 4) & 0xa0;
  81                         if (st != 0xa0)
  82                                 break;
  83                         if (virtual_dma_mode)
  84                                 outb_p(*lptr, virtual_dma_port + 5);
  85                         else
  86                                 *lptr = inb_p(virtual_dma_port + 5);
  87                 }
  88                 virtual_dma_count = lcount;
  89                 virtual_dma_addr = lptr;
  90                 st = inb(virtual_dma_port + 4);
  91         }
  92
  93 #ifdef TRACE_FLPY_INT
  94         calls++;
  95 #endif
  96         if (st == 0x20)
  97                 return IRQ_HANDLED;
  98         if (!(st & 0x20)) {
  99                 virtual_dma_residue += virtual_dma_count;
 100                 virtual_dma_count = 0;
 101 #ifdef TRACE_FLPY_INT
 102                 printk(KERN_DEBUG "count=%x, residue=%x calls=%d bytes=%d dma_wait=%d\n",
 103                        virtual_dma_count, virtual_dma_residue, calls, bytes,
 104                        dma_wait);
 105                 calls = 0;
 106                 dma_wait = 0;
 107 #endif
 108                 doing_pdma = 0;
 109                 floppy_interrupt(irq, dev_id);
 110                 return IRQ_HANDLED;
 111         }
 112 #ifdef TRACE_FLPY_INT
 113         if (!virtual_dma_count)
 114                 dma_wait++;
 115 #endif
 116         return IRQ_HANDLED;
 117 }
 118
 119 static void fd_disable_dma(void)
 120 {
 121         if (!(can_use_virtual_dma & 1))
 122                 disable_dma(FLOPPY_DMA);
 123         doing_pdma = 0;
 124         virtual_dma_residue += virtual_dma_count;
 125         virtual_dma_count = 0;
 126 }
 127
 128 static int vdma_request_dma(unsigned int dmanr, const char *device_id)
 129 {
 130         return 0;
 131 }
 132
 133 static void vdma_nop(unsigned int dummy)
 134 {
 135 }
 136
 137
 138 static int vdma_get_dma_residue(unsigned int dummy)
 139 {
 140         return virtual_dma_count + virtual_dma_residue;
 141 }
 142
 143
 144 static int fd_request_irq(void)
 145 {
 146         if (can_use_virtual_dma)
 147                 return request_irq(FLOPPY_IRQ, floppy_hardint,
 148                                    0, "floppy", NULL);
 149         else
 150                 return request_irq(FLOPPY_IRQ, floppy_interrupt,
 151                                    0, "floppy", NULL);
 152 }
 153
 154 static unsigned long dma_mem_alloc(unsigned long size)
 155 {
 156         return __get_dma_pages(GFP_KERNEL|__GFP_NORETRY, get_order(size));
 157 }
 158
 159
 160 static unsigned long vdma_mem_alloc(unsigned long size)
 161 {
 162         return (unsigned long)vmalloc(size);
 163
 164 }
 165
 166 #define nodma_mem_alloc(size) vdma_mem_alloc(size)
 167
 168 static void _fd_dma_mem_free(unsigned long addr, unsigned long size)
 169 {
 170         if ((unsigned long)addr >= (unsigned long)high_memory)
 171                 vfree((void *)addr);
 172         else
 173                 free_pages(addr, get_order(size));
 174 }
 175
 176 #define fd_dma_mem_free(addr, size)  _fd_dma_mem_free(addr, size)
 177
 178 static void _fd_chose_dma_mode(char *addr, unsigned long size)
 179 {
 180         if (can_use_virtual_dma == 2) {
 181                 if ((unsigned long)addr >= (unsigned long)high_memory ||
 182                     isa_virt_to_bus(addr) >= 0x1000000 ||
 183                     _CROSS_64KB(addr, size, 0))
 184                         use_virtual_dma = 1;
 185                 else
 186                         use_virtual_dma = 0;
 187         } else {
 188                 use_virtual_dma = can_use_virtual_dma & 1;
 189         }
 190 }
 191
 192 #define fd_chose_dma_mode(addr, size) _fd_chose_dma_mode(addr, size)
 193
 194
 195 static int vdma_dma_setup(char *addr, unsigned long size, int mode, int io)
 196 {
 197         doing_pdma = 1;
 198         virtual_dma_port = io;
 199         virtual_dma_mode = (mode == DMA_MODE_WRITE);
 200         virtual_dma_addr = addr;
 201         virtual_dma_count = size;
 202         virtual_dma_residue = 0;
 203         return 0;
 204 }
 205
 206 static int hard_dma_setup(char *addr, unsigned long size, int mode, int io)
 207 {
 208 #ifdef FLOPPY_SANITY_CHECK
 209         if (CROSS_64KB(addr, size)) {
 210                 printk("DMA crossing 64-K boundary %p-%p\n", addr, addr+size);
 211                 return -1;
 212         }
 213 #endif
 214         /* actual, physical DMA */
 215         doing_pdma = 0;
 216         clear_dma_ff(FLOPPY_DMA);
 217         set_dma_mode(FLOPPY_DMA, mode);
 218         set_dma_addr(FLOPPY_DMA, isa_virt_to_bus(addr));
 219         set_dma_count(FLOPPY_DMA, size);
 220         enable_dma(FLOPPY_DMA);
 221         return 0;
 222 }
 223
 224 static struct fd_routine_l {
 225         int (*_request_dma)(unsigned int dmanr, const char *device_id);
 226         void (*_free_dma)(unsigned int dmanr);
 227         int (*_get_dma_residue)(unsigned int dummy);
 228         unsigned long (*_dma_mem_alloc)(unsigned long size);
 229         int (*_dma_setup)(char *addr, unsigned long size, int mode, int io);
 230 } fd_routine[] = {
 231         {
 232                 request_dma,
 233                 free_dma,
 234                 get_dma_residue,
 235                 dma_mem_alloc,
 236                 hard_dma_setup
 237         },
 238         {
 239                 vdma_request_dma,
 240                 vdma_nop,
 241                 vdma_get_dma_residue,
 242                 vdma_mem_alloc,
 243                 vdma_dma_setup
 244         }
 245 };
 246
 247
 248 static int FDC1 = 0x3f0;
 249 static int FDC2 = -1;
 250
 251 /*
 252  * Floppy types are stored in the rtc's CMOS RAM and so rtc_lock
 253  * is needed to prevent corrupted CMOS RAM in case "insmod floppy"
 254  * coincides with another rtc CMOS user.                Paul G.
 255  */
 256 #define FLOPPY0_TYPE                                    \
 257 ({                                                      \
 258         unsigned long flags;                            \
 259         unsigned char val;                              \
 260         spin_lock_irqsave(&rtc_lock, flags);            \
 261         val = (CMOS_READ(0x10) >> 4) & 15;              \
 262         spin_unlock_irqrestore(&rtc_lock, flags);       \
 263         val;                                            \
 264 })
 265
 266 #define FLOPPY1_TYPE                                    \
 267 ({                                                      \
 268         unsigned long flags;                            \
 269         unsigned char val;                              \
 270         spin_lock_irqsave(&rtc_lock, flags);            \
 271         val = CMOS_READ(0x10) & 15;                     \
 272         spin_unlock_irqrestore(&rtc_lock, flags);       \
 273         val;                                            \
 274 })
 275
 276 #define N_FDC 2
 277 #define N_DRIVE 8
 278
 279 #define EXTRA_FLOPPY_PARAMS
 280
 281 #endif /* _ASM_X86_FLOPPY_H */