xref: /openbmc/linux/arch/parisc/include/asm/floppy.h (revision 8795a739)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*    Architecture specific parts of the Floppy driver
3  *
4  *    Linux/PA-RISC Project (http://www.parisc-linux.org/)
5  *    Copyright (C) 2000 Matthew Wilcox (willy a debian . org)
6  *    Copyright (C) 2000 Dave Kennedy
7  */
8 #ifndef __ASM_PARISC_FLOPPY_H
9 #define __ASM_PARISC_FLOPPY_H
10 
11 #include <linux/vmalloc.h>
12 
13 
14 /*
15  * The DMA channel used by the floppy controller cannot access data at
16  * addresses >= 16MB
17  *
18  * Went back to the 1MB limit, as some people had problems with the floppy
19  * driver otherwise. It doesn't matter much for performance anyway, as most
20  * floppy accesses go through the track buffer.
21  */
22 #define _CROSS_64KB(a,s,vdma) \
23 (!(vdma) && ((unsigned long)(a)/K_64 != ((unsigned long)(a) + (s) - 1) / K_64))
24 
25 #define CROSS_64KB(a,s) _CROSS_64KB(a,s,use_virtual_dma & 1)
26 
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(port)			readb(port)
33 #define fd_outb(value, port)		writeb(value, port)
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 
46 static int virtual_dma_count=0;
47 static int virtual_dma_residue=0;
48 static char *virtual_dma_addr=0;
49 static int virtual_dma_mode=0;
50 static int doing_pdma=0;
51 
52 static void floppy_hardint(int irq, void *dev_id, struct pt_regs * regs)
53 {
54 	register unsigned char st;
55 
56 #undef TRACE_FLPY_INT
57 
58 #ifdef TRACE_FLPY_INT
59 	static int calls=0;
60 	static int bytes=0;
61 	static int dma_wait=0;
62 #endif
63 	if (!doing_pdma) {
64 		floppy_interrupt(irq, dev_id, regs);
65 		return;
66 	}
67 
68 #ifdef TRACE_FLPY_INT
69 	if(!calls)
70 		bytes = virtual_dma_count;
71 #endif
72 
73 	{
74 		register int lcount;
75 		register char *lptr = virtual_dma_addr;
76 
77 		for (lcount = virtual_dma_count; lcount; lcount--) {
78 			st = fd_inb(virtual_dma_port+4) & 0xa0 ;
79 			if (st != 0xa0)
80 				break;
81 			if (virtual_dma_mode) {
82 				fd_outb(*lptr, virtual_dma_port+5);
83 			} else {
84 				*lptr = fd_inb(virtual_dma_port+5);
85 			}
86 			lptr++;
87 		}
88 		virtual_dma_count = lcount;
89 		virtual_dma_addr = lptr;
90 		st = fd_inb(virtual_dma_port+4);
91 	}
92 
93 #ifdef TRACE_FLPY_INT
94 	calls++;
95 #endif
96 	if (st == 0x20)
97 		return;
98 	if (!(st & 0x20)) {
99 		virtual_dma_residue += virtual_dma_count;
100 		virtual_dma_count = 0;
101 #ifdef TRACE_FLPY_INT
102 		printk("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, regs);
110 		return;
111 	}
112 #ifdef TRACE_FLPY_INT
113 	if (!virtual_dma_count)
114 		dma_wait++;
115 #endif
116 }
117 
118 static 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 
127 static int vdma_request_dma(unsigned int dmanr, const char * device_id)
128 {
129 	return 0;
130 }
131 
132 static void vdma_nop(unsigned int dummy)
133 {
134 }
135 
136 
137 static int vdma_get_dma_residue(unsigned int dummy)
138 {
139 	return virtual_dma_count + virtual_dma_residue;
140 }
141 
142 
143 static int fd_request_irq(void)
144 {
145 	if(can_use_virtual_dma)
146 		return request_irq(FLOPPY_IRQ, floppy_hardint,
147 				   0, "floppy", NULL);
148 	else
149 		return request_irq(FLOPPY_IRQ, floppy_interrupt,
150 				   0, "floppy", NULL);
151 }
152 
153 static unsigned long dma_mem_alloc(unsigned long size)
154 {
155 	return __get_dma_pages(GFP_KERNEL, get_order(size));
156 }
157 
158 
159 static 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 
167 static void _fd_dma_mem_free(unsigned long addr, unsigned long size)
168 {
169 	if((unsigned int) addr >= (unsigned int) high_memory)
170 		return 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 
177 static void _fd_chose_dma_mode(char *addr, unsigned long size)
178 {
179 	if(can_use_virtual_dma == 2) {
180 		if((unsigned int) addr >= (unsigned int) high_memory ||
181 		   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 
194 static 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 
205 static 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,virt_to_bus(addr));
218 	set_dma_count(FLOPPY_DMA,size);
219 	enable_dma(FLOPPY_DMA);
220 	return 0;
221 }
222 
223 static 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 
247 static int FDC1 = 0x3f0; /* Lies.  Floppy controller is memory mapped, not io mapped */
248 static int FDC2 = -1;
249 
250 #define FLOPPY0_TYPE	0
251 #define FLOPPY1_TYPE	0
252 
253 #define N_FDC 1
254 #define N_DRIVE 8
255 
256 #define EXTRA_FLOPPY_PARAMS
257 
258 #endif /* __ASM_PARISC_FLOPPY_H */
259