xref: /openbmc/linux/arch/x86/include/asm/floppy.h (revision feac8c8b)
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		= 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 
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 */
282