linux/arch/x86/include/asm/floppy.h
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   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
  48static int virtual_dma_count;
  49static int virtual_dma_residue;
  50static char *virtual_dma_addr;
  51static int virtual_dma_mode;
  52static int doing_pdma;
  53
  54static 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
 119static 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
 128static int vdma_request_dma(unsigned int dmanr, const char *device_id)
 129{
 130        return 0;
 131}
 132
 133static void vdma_nop(unsigned int dummy)
 134{
 135}
 136
 137
 138static int vdma_get_dma_residue(unsigned int dummy)
 139{
 140        return virtual_dma_count + virtual_dma_residue;
 141}
 142
 143
 144static 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
 154static unsigned long dma_mem_alloc(unsigned long size)
 155{
 156        return __get_dma_pages(GFP_KERNEL|__GFP_NORETRY, get_order(size));
 157}
 158
 159
 160static 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
 168static 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
 178static 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
 195static 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
 206static 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
 224static 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           = request_dma,
 233                ._free_dma              = free_dma,
 234                ._get_dma_residue       = get_dma_residue,
 235                ._dma_mem_alloc         = dma_mem_alloc,
 236                ._dma_setup             = hard_dma_setup
 237        },
 238        {
 239                ._request_dma           = vdma_request_dma,
 240                ._free_dma              = vdma_nop,
 241                ._get_dma_residue       = vdma_get_dma_residue,
 242                ._dma_mem_alloc         = vdma_mem_alloc,
 243                ._dma_setup             = vdma_dma_setup
 244        }
 245};
 246
 247
 248static int FDC1 = 0x3f0;
 249static 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 */
 282