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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 
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  IRQF_DISABLED, "floppy", NULL);
149  else
150  return request_irq(FLOPPY_IRQ, floppy_interrupt,
151  IRQF_DISABLED, "floppy", NULL);
152 }
153 
154 static unsigned long dma_mem_alloc(unsigned long size)
155 {
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,
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 */