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/sizes.h>
 14#include <linux/vmalloc.h>
 15
 16/*
 17 * The DMA channel used by the floppy controller cannot access data at
 18 * addresses >= 16MB
 19 *
 20 * Went back to the 1MB limit, as some people had problems with the floppy
 21 * driver otherwise. It doesn't matter much for performance anyway, as most
 22 * floppy accesses go through the track buffer.
 23 */
 24#define _CROSS_64KB(a, s, vdma)						\
 25	(!(vdma) &&							\
 26	 ((unsigned long)(a) / SZ_64K != ((unsigned long)(a) + (s) - 1) / SZ_64K))
 27
 28#define SW fd_routine[use_virtual_dma & 1]
 29#define CSW fd_routine[can_use_virtual_dma & 1]
 30
 31
 32#define fd_inb(base, reg)		inb_p((base) + (reg))
 33#define fd_outb(value, base, reg)	outb_p(value, (base) + (reg))
 34
 35#define fd_request_dma()	CSW._request_dma(FLOPPY_DMA, "floppy")
 36#define fd_free_dma()		CSW._free_dma(FLOPPY_DMA)
 37#define fd_enable_irq()		enable_irq(FLOPPY_IRQ)
 38#define fd_disable_irq()	disable_irq(FLOPPY_IRQ)
 39#define fd_free_irq()		free_irq(FLOPPY_IRQ, NULL)
 40#define fd_get_dma_residue()	SW._get_dma_residue(FLOPPY_DMA)
 41#define fd_dma_mem_alloc(size)	SW._dma_mem_alloc(size)
 42#define fd_dma_setup(addr, size, mode, io) SW._dma_setup(addr, size, mode, io)
 43
 44#define FLOPPY_CAN_FALLBACK_ON_NODMA
 45
 46static int virtual_dma_count;
 47static int virtual_dma_residue;
 48static char *virtual_dma_addr;
 49static int virtual_dma_mode;
 50static int doing_pdma;
 51
 52static irqreturn_t floppy_hardint(int irq, void *dev_id)
 53{
 54	unsigned char st;
 55
 56#undef TRACE_FLPY_INT
 57
 58#ifdef TRACE_FLPY_INT
 59	static int calls;
 60	static int bytes;
 61	static int dma_wait;
 62#endif
 63	if (!doing_pdma)
 64		return floppy_interrupt(irq, dev_id);
 65
 66#ifdef TRACE_FLPY_INT
 67	if (!calls)
 68		bytes = virtual_dma_count;
 69#endif
 70
 71	{
 72		int lcount;
 73		char *lptr;
 74
 75		for (lcount = virtual_dma_count, lptr = virtual_dma_addr;
 76		     lcount; lcount--, lptr++) {
 77			st = inb(virtual_dma_port + FD_STATUS);
 78			st &= STATUS_DMA | STATUS_READY;
 79			if (st != (STATUS_DMA | STATUS_READY))
 80				break;
 81			if (virtual_dma_mode)
 82				outb_p(*lptr, virtual_dma_port + FD_DATA);
 83			else
 84				*lptr = inb_p(virtual_dma_port + FD_DATA);
 85		}
 86		virtual_dma_count = lcount;
 87		virtual_dma_addr = lptr;
 88		st = inb(virtual_dma_port + FD_STATUS);
 89	}
 90
 91#ifdef TRACE_FLPY_INT
 92	calls++;
 93#endif
 94	if (st == STATUS_DMA)
 95		return IRQ_HANDLED;
 96	if (!(st & STATUS_DMA)) {
 97		virtual_dma_residue += virtual_dma_count;
 98		virtual_dma_count = 0;
 99#ifdef TRACE_FLPY_INT
100		printk(KERN_DEBUG "count=%x, residue=%x calls=%d bytes=%d dma_wait=%d\n",
101		       virtual_dma_count, virtual_dma_residue, calls, bytes,
102		       dma_wait);
103		calls = 0;
104		dma_wait = 0;
105#endif
106		doing_pdma = 0;
107		floppy_interrupt(irq, dev_id);
108		return IRQ_HANDLED;
109	}
110#ifdef TRACE_FLPY_INT
111	if (!virtual_dma_count)
112		dma_wait++;
113#endif
114	return IRQ_HANDLED;
115}
116
117static void fd_disable_dma(void)
118{
119	if (!(can_use_virtual_dma & 1))
120		disable_dma(FLOPPY_DMA);
121	doing_pdma = 0;
122	virtual_dma_residue += virtual_dma_count;
123	virtual_dma_count = 0;
124}
125
126static int vdma_request_dma(unsigned int dmanr, const char *device_id)
127{
128	return 0;
129}
130
131static void vdma_nop(unsigned int dummy)
132{
133}
134
135
136static int vdma_get_dma_residue(unsigned int dummy)
137{
138	return virtual_dma_count + virtual_dma_residue;
139}
140
141
142static int fd_request_irq(void)
143{
144	if (can_use_virtual_dma)
145		return request_irq(FLOPPY_IRQ, floppy_hardint,
146				   0, "floppy", NULL);
147	else
148		return request_irq(FLOPPY_IRQ, floppy_interrupt,
149				   0, "floppy", NULL);
150}
151
152static unsigned long dma_mem_alloc(unsigned long size)
153{
154	return __get_dma_pages(GFP_KERNEL|__GFP_NORETRY, get_order(size));
155}
156
157
158static unsigned long vdma_mem_alloc(unsigned long size)
159{
160	return (unsigned long)vmalloc(size);
161
162}
163
164#define nodma_mem_alloc(size) vdma_mem_alloc(size)
165
166static void _fd_dma_mem_free(unsigned long addr, unsigned long size)
167{
168	if ((unsigned long)addr >= (unsigned long)high_memory)
169		vfree((void *)addr);
170	else
171		free_pages(addr, get_order(size));
172}
173
174#define fd_dma_mem_free(addr, size)  _fd_dma_mem_free(addr, size)
175
176static void _fd_chose_dma_mode(char *addr, unsigned long size)
177{
178	if (can_use_virtual_dma == 2) {
179		if ((unsigned long)addr >= (unsigned long)high_memory ||
180		    isa_virt_to_bus(addr) >= 0x1000000 ||
181		    _CROSS_64KB(addr, size, 0))
182			use_virtual_dma = 1;
183		else
184			use_virtual_dma = 0;
185	} else {
186		use_virtual_dma = can_use_virtual_dma & 1;
187	}
188}
189
190#define fd_chose_dma_mode(addr, size) _fd_chose_dma_mode(addr, size)
191
192
193static int vdma_dma_setup(char *addr, unsigned long size, int mode, int io)
194{
195	doing_pdma = 1;
196	virtual_dma_port = io;
197	virtual_dma_mode = (mode == DMA_MODE_WRITE);
198	virtual_dma_addr = addr;
199	virtual_dma_count = size;
200	virtual_dma_residue = 0;
201	return 0;
202}
203
204static int hard_dma_setup(char *addr, unsigned long size, int mode, int io)
205{
206#ifdef FLOPPY_SANITY_CHECK
207	if (_CROSS_64KB(addr, size, use_virtual_dma & 1)) {
208		printk("DMA crossing 64-K boundary %p-%p\n", addr, addr+size);
209		return -1;
210	}
211#endif
212	/* actual, physical DMA */
213	doing_pdma = 0;
214	clear_dma_ff(FLOPPY_DMA);
215	set_dma_mode(FLOPPY_DMA, mode);
216	set_dma_addr(FLOPPY_DMA, isa_virt_to_bus(addr));
217	set_dma_count(FLOPPY_DMA, size);
218	enable_dma(FLOPPY_DMA);
219	return 0;
220}
221
222static struct fd_routine_l {
223	int (*_request_dma)(unsigned int dmanr, const char *device_id);
224	void (*_free_dma)(unsigned int dmanr);
225	int (*_get_dma_residue)(unsigned int dummy);
226	unsigned long (*_dma_mem_alloc)(unsigned long size);
227	int (*_dma_setup)(char *addr, unsigned long size, int mode, int io);
228} fd_routine[] = {
229	{
230		._request_dma		= request_dma,
231		._free_dma		= free_dma,
232		._get_dma_residue	= get_dma_residue,
233		._dma_mem_alloc		= dma_mem_alloc,
234		._dma_setup		= hard_dma_setup
235	},
236	{
237		._request_dma		= vdma_request_dma,
238		._free_dma		= vdma_nop,
239		._get_dma_residue	= vdma_get_dma_residue,
240		._dma_mem_alloc		= vdma_mem_alloc,
241		._dma_setup		= vdma_dma_setup
242	}
243};
244
245
246static int FDC1 = 0x3f0;
247static int FDC2 = -1;
248
249/*
250 * Floppy types are stored in the rtc's CMOS RAM and so rtc_lock
251 * is needed to prevent corrupted CMOS RAM in case "insmod floppy"
252 * coincides with another rtc CMOS user.		Paul G.
253 */
254#define FLOPPY0_TYPE					\
255({							\
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({							\
266	unsigned long flags;				\
267	unsigned char val;				\
268	spin_lock_irqsave(&rtc_lock, flags);		\
269	val = CMOS_READ(0x10) & 15;			\
270	spin_unlock_irqrestore(&rtc_lock, flags);	\
271	val;						\
272})
273
274#define N_FDC 2
275#define N_DRIVE 8
276
277#define EXTRA_FLOPPY_PARAMS
278
279#endif /* _ASM_X86_FLOPPY_H */