tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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) && ((unsigned long)(a)/K_64 != ((unsigned long)(a) + (s) - 1) / K_64))
25
26#define CROSS_64KB(a,s) _CROSS_64KB(a,s,use_virtual_dma & 1)
27
28
29#define SW fd_routine[use_virtual_dma&1]
30#define CSW fd_routine[can_use_virtual_dma & 1]
31
32
33#define fd_inb(port) inb_p(port)
34#define fd_outb(value,port) outb_p(value,port)
35
36#define fd_request_dma() CSW._request_dma(FLOPPY_DMA,"floppy")
37#define fd_free_dma() CSW._free_dma(FLOPPY_DMA)
38#define fd_enable_irq() enable_irq(FLOPPY_IRQ)
39#define fd_disable_irq() disable_irq(FLOPPY_IRQ)
40#define fd_free_irq() free_irq(FLOPPY_IRQ, NULL)
41#define fd_get_dma_residue() SW._get_dma_residue(FLOPPY_DMA)
42#define fd_dma_mem_alloc(size) SW._dma_mem_alloc(size)
43#define fd_dma_setup(addr, size, mode, io) SW._dma_setup(addr, size, mode, io)
44
45#define FLOPPY_CAN_FALLBACK_ON_NODMA
46
47static int virtual_dma_count;
48static int virtual_dma_residue;
49static char *virtual_dma_addr;
50static int virtual_dma_mode;
51static int doing_pdma;
52
53static irqreturn_t floppy_hardint(int irq, void *dev_id)
54{
55 register unsigned char st;
56
57#undef TRACE_FLPY_INT
58
59#ifdef TRACE_FLPY_INT
60 static int calls=0;
61 static int bytes=0;
62 static int dma_wait=0;
63#endif
64 if (!doing_pdma)
65 return floppy_interrupt(irq, dev_id);
66
67#ifdef TRACE_FLPY_INT
68 if(!calls)
69 bytes = virtual_dma_count;
70#endif
71
72 {
73 register int lcount;
74 register char *lptr;
75
76 st = 1;
77 for(lcount=virtual_dma_count, lptr=virtual_dma_addr;
78 lcount; lcount--, lptr++) {
79 st=inb(virtual_dma_port+4) & 0xa0 ;
80 if(st != 0xa0)
81 break;
82 if(virtual_dma_mode)
83 outb_p(*lptr, virtual_dma_port+5);
84 else
85 *lptr = inb_p(virtual_dma_port+5);
86 }
87 virtual_dma_count = lcount;
88 virtual_dma_addr = lptr;
89 st = inb(virtual_dma_port+4);
90 }
91
92#ifdef TRACE_FLPY_INT
93 calls++;
94#endif
95 if(st == 0x20)
96 return IRQ_HANDLED;
97 if(!(st & 0x20)) {
98 virtual_dma_residue += virtual_dma_count;
99 virtual_dma_count=0;
100#ifdef TRACE_FLPY_INT
101 printk("count=%x, residue=%x calls=%d bytes=%d dma_wait=%d\n",
102 virtual_dma_count, virtual_dma_residue, calls, bytes,
103 dma_wait);
104 calls = 0;
105 dma_wait=0;
106#endif
107 doing_pdma = 0;
108 floppy_interrupt(irq, dev_id);
109 return IRQ_HANDLED;
110 }
111#ifdef TRACE_FLPY_INT
112 if(!virtual_dma_count)
113 dma_wait++;
114#endif
115 return IRQ_HANDLED;
116}
117
118static void fd_disable_dma(void)
119{
120 if(! (can_use_virtual_dma & 1))
121 disable_dma(FLOPPY_DMA);
122 doing_pdma = 0;
123 virtual_dma_residue += virtual_dma_count;
124 virtual_dma_count=0;
125}
126
127static int vdma_request_dma(unsigned int dmanr, const char * device_id)
128{
129 return 0;
130}
131
132static void vdma_nop(unsigned int dummy)
133{
134}
135
136
137static int vdma_get_dma_residue(unsigned int dummy)
138{
139 return virtual_dma_count + virtual_dma_residue;
140}
141
142
143static int fd_request_irq(void)
144{
145 if(can_use_virtual_dma)
146 return request_irq(FLOPPY_IRQ, floppy_hardint,
147 IRQF_DISABLED, "floppy", NULL);
148 else
149 return request_irq(FLOPPY_IRQ, floppy_interrupt,
150 IRQF_DISABLED, "floppy", NULL);
151}
152
153static unsigned long dma_mem_alloc(unsigned long size)
154{
155 return __get_dma_pages(GFP_KERNEL|__GFP_NORETRY,get_order(size));
156}
157
158
159static unsigned long vdma_mem_alloc(unsigned long size)
160{
161 return (unsigned long) vmalloc(size);
162
163}
164
165#define nodma_mem_alloc(size) vdma_mem_alloc(size)
166
167static void _fd_dma_mem_free(unsigned long addr, unsigned long size)
168{
169 if((unsigned long) addr >= (unsigned long) high_memory)
170 vfree((void *)addr);
171 else
172 free_pages(addr, get_order(size));
173}
174
175#define fd_dma_mem_free(addr, size) _fd_dma_mem_free(addr, size)
176
177static void _fd_chose_dma_mode(char *addr, unsigned long size)
178{
179 if(can_use_virtual_dma == 2) {
180 if((unsigned long) addr >= (unsigned long) high_memory ||
181 isa_virt_to_bus(addr) >= 0x1000000 ||
182 _CROSS_64KB(addr, size, 0))
183 use_virtual_dma = 1;
184 else
185 use_virtual_dma = 0;
186 } else {
187 use_virtual_dma = can_use_virtual_dma & 1;
188 }
189}
190
191#define fd_chose_dma_mode(addr, size) _fd_chose_dma_mode(addr, size)
192
193
194static int vdma_dma_setup(char *addr, unsigned long size, int mode, int io)
195{
196 doing_pdma = 1;
197 virtual_dma_port = io;
198 virtual_dma_mode = (mode == DMA_MODE_WRITE);
199 virtual_dma_addr = addr;
200 virtual_dma_count = size;
201 virtual_dma_residue = 0;
202 return 0;
203}
204
205static int hard_dma_setup(char *addr, unsigned long size, int mode, int io)
206{
207#ifdef FLOPPY_SANITY_CHECK
208 if (CROSS_64KB(addr, size)) {
209 printk("DMA crossing 64-K boundary %p-%p\n", addr, addr+size);
210 return -1;
211 }
212#endif
213 /* actual, physical DMA */
214 doing_pdma = 0;
215 clear_dma_ff(FLOPPY_DMA);
216 set_dma_mode(FLOPPY_DMA,mode);
217 set_dma_addr(FLOPPY_DMA,isa_virt_to_bus(addr));
218 set_dma_count(FLOPPY_DMA,size);
219 enable_dma(FLOPPY_DMA);
220 return 0;
221}
222
223static struct fd_routine_l {
224 int (*_request_dma)(unsigned int dmanr, const char * device_id);
225 void (*_free_dma)(unsigned int dmanr);
226 int (*_get_dma_residue)(unsigned int dummy);
227 unsigned long (*_dma_mem_alloc) (unsigned long size);
228 int (*_dma_setup)(char *addr, unsigned long size, int mode, int io);
229} fd_routine[] = {
230 {
231 request_dma,
232 free_dma,
233 get_dma_residue,
234 dma_mem_alloc,
235 hard_dma_setup
236 },
237 {
238 vdma_request_dma,
239 vdma_nop,
240 vdma_get_dma_residue,
241 vdma_mem_alloc,
242 vdma_dma_setup
243 }
244};
245
246
247static int FDC1 = 0x3f0;
248static int FDC2 = -1;
249
250/*
251 * Floppy types are stored in the rtc's CMOS RAM and so rtc_lock
252 * is needed to prevent corrupted CMOS RAM in case "insmod floppy"
253 * coincides with another rtc CMOS user. Paul G.
254 */
255#define FLOPPY0_TYPE ({ \
256 unsigned long flags; \
257 unsigned char val; \
258 spin_lock_irqsave(&rtc_lock, flags); \
259 val = (CMOS_READ(0x10) >> 4) & 15; \
260 spin_unlock_irqrestore(&rtc_lock, flags); \
261 val; \
262})
263
264#define FLOPPY1_TYPE ({ \
265 unsigned long flags; \
266 unsigned char val; \
267 spin_lock_irqsave(&rtc_lock, flags); \
268 val = CMOS_READ(0x10) & 15; \
269 spin_unlock_irqrestore(&rtc_lock, flags); \
270 val; \
271})
272
273#define N_FDC 2
274#define N_DRIVE 8
275
276#define EXTRA_FLOPPY_PARAMS
277
278#endif /* _ASM_X86_FLOPPY_H */