File: /usr/src/linux/drivers/net/hamradio/soundmodem/smdma.h
1 /*****************************************************************************/
2
3 /*
4 * smdma.h -- soundcard radio modem driver dma buffer routines.
5 *
6 * Copyright (C) 1996 Thomas Sailer (sailer@ife.ee.ethz.ch)
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
21 *
22 * Please note that the GPL allows you to use the driver, NOT the radio.
23 * In order to use the radio, you need a license from the communications
24 * authority of your country.
25 *
26 */
27
28 #ifndef _SMDMA_H
29 #define _SMDMA_H
30
31 /* ---------------------------------------------------------------------- */
32
33 #include "sm.h"
34
35 /* ---------------------------------------------------------------------- */
36
37 #define DMA_MODE_AUTOINIT 0x10
38 #define NUM_FRAGMENTS 4
39
40 /*
41 * NOTE: make sure that hdlcdrv_hdlcbuffer contains enough space
42 * for the modulator to fill the whole DMA buffer without underrun
43 * at the highest possible baud rate, otherwise the TX state machine will
44 * not work correctly. That is (9k6 FSK): HDLCDRV_HDLCBUFFER > 6*NUM_FRAGMENTS
45 */
46
47 /* --------------------------------------------------------------------- */
48 /*
49 * ===================== DMA buffer management ===========================
50 */
51
52 /*
53 * returns the number of samples per fragment
54 */
55 extern __inline__ unsigned int dma_setup(struct sm_state *sm, int send, unsigned int dmanr)
56 {
57 if (send) {
58 disable_dma(dmanr);
59 clear_dma_ff(dmanr);
60 set_dma_mode(dmanr, DMA_MODE_WRITE | DMA_MODE_AUTOINIT);
61 set_dma_addr(dmanr, virt_to_bus(sm->dma.obuf));
62 set_dma_count(dmanr, sm->dma.ofragsz * NUM_FRAGMENTS);
63 enable_dma(dmanr);
64 if (sm->dma.o16bit)
65 return sm->dma.ofragsz/2;
66 return sm->dma.ofragsz;
67 } else {
68 disable_dma(dmanr);
69 clear_dma_ff(dmanr);
70 set_dma_mode(dmanr, DMA_MODE_READ | DMA_MODE_AUTOINIT);
71 set_dma_addr(dmanr, virt_to_bus(sm->dma.ibuf));
72 set_dma_count(dmanr, sm->dma.ifragsz * NUM_FRAGMENTS);
73 enable_dma(dmanr);
74 if (sm->dma.i16bit)
75 return sm->dma.ifragsz/2;
76 return sm->dma.ifragsz;
77 }
78 }
79
80 /* --------------------------------------------------------------------- */
81
82 extern __inline__ unsigned int dma_ptr(struct sm_state *sm, int send, unsigned int dmanr,
83 unsigned int *curfrag)
84 {
85 unsigned int dmaptr, sz, frg, offs;
86
87 dmaptr = get_dma_residue(dmanr);
88 if (send) {
89 sz = sm->dma.ofragsz * NUM_FRAGMENTS;
90 if (dmaptr == 0 || dmaptr > sz)
91 dmaptr = sz;
92 dmaptr--;
93 frg = dmaptr / sm->dma.ofragsz;
94 offs = (dmaptr % sm->dma.ofragsz) + 1;
95 *curfrag = NUM_FRAGMENTS - 1 - frg;
96 #ifdef SM_DEBUG
97 if (!sm->debug_vals.dma_residue || offs < sm->debug_vals.dma_residue)
98 sm->debug_vals.dma_residue = offs;
99 #endif /* SM_DEBUG */
100 if (sm->dma.o16bit)
101 return offs/2;
102 return offs;
103 } else {
104 sz = sm->dma.ifragsz * NUM_FRAGMENTS;
105 if (dmaptr == 0 || dmaptr > sz)
106 dmaptr = sz;
107 dmaptr--;
108 frg = dmaptr / sm->dma.ifragsz;
109 offs = (dmaptr % sm->dma.ifragsz) + 1;
110 *curfrag = NUM_FRAGMENTS - 1 - frg;
111 #ifdef SM_DEBUG
112 if (!sm->debug_vals.dma_residue || offs < sm->debug_vals.dma_residue)
113 sm->debug_vals.dma_residue = offs;
114 #endif /* SM_DEBUG */
115 if (sm->dma.i16bit)
116 return offs/2;
117 return offs;
118 }
119 }
120
121 /* --------------------------------------------------------------------- */
122
123 extern __inline__ int dma_end_transmit(struct sm_state *sm, unsigned int curfrag)
124 {
125 unsigned int diff = (NUM_FRAGMENTS + curfrag - sm->dma.ofragptr) % NUM_FRAGMENTS;
126
127 sm->dma.ofragptr = curfrag;
128 if (sm->dma.ptt_cnt <= 0) {
129 sm->dma.ptt_cnt = 0;
130 return 0;
131 }
132 sm->dma.ptt_cnt -= diff;
133 if (sm->dma.ptt_cnt <= 0) {
134 sm->dma.ptt_cnt = 0;
135 return -1;
136 }
137 return 0;
138 }
139
140 extern __inline__ void dma_transmit(struct sm_state *sm)
141 {
142 void *p;
143
144 while (sm->dma.ptt_cnt < NUM_FRAGMENTS && hdlcdrv_ptt(&sm->hdrv)) {
145 p = (unsigned char *)sm->dma.obuf + sm->dma.ofragsz *
146 ((sm->dma.ofragptr + sm->dma.ptt_cnt) % NUM_FRAGMENTS);
147 if (sm->dma.o16bit) {
148 time_exec(sm->debug_vals.mod_cyc,
149 sm->mode_tx->modulator_s16(sm, p, sm->dma.ofragsz/2));
150 } else {
151 time_exec(sm->debug_vals.mod_cyc,
152 sm->mode_tx->modulator_u8(sm, p, sm->dma.ofragsz));
153 }
154 sm->dma.ptt_cnt++;
155 }
156 }
157
158 extern __inline__ void dma_init_transmit(struct sm_state *sm)
159 {
160 sm->dma.ofragptr = 0;
161 sm->dma.ptt_cnt = 0;
162 }
163
164 extern __inline__ void dma_start_transmit(struct sm_state *sm)
165 {
166 sm->dma.ofragptr = 0;
167 if (sm->dma.o16bit) {
168 time_exec(sm->debug_vals.mod_cyc,
169 sm->mode_tx->modulator_s16(sm, sm->dma.obuf, sm->dma.ofragsz/2));
170 } else {
171 time_exec(sm->debug_vals.mod_cyc,
172 sm->mode_tx->modulator_u8(sm, sm->dma.obuf, sm->dma.ofragsz));
173 }
174 sm->dma.ptt_cnt = 1;
175 }
176
177 extern __inline__ void dma_clear_transmit(struct sm_state *sm)
178 {
179 sm->dma.ptt_cnt = 0;
180 memset(sm->dma.obuf, (sm->dma.o16bit) ? 0 : 0x80, sm->dma.ofragsz * NUM_FRAGMENTS);
181 }
182
183 /* --------------------------------------------------------------------- */
184
185 extern __inline__ void dma_receive(struct sm_state *sm, unsigned int curfrag)
186 {
187 void *p;
188
189 while (sm->dma.ifragptr != curfrag) {
190 if (sm->dma.ifragptr)
191 p = (unsigned char *)sm->dma.ibuf +
192 sm->dma.ifragsz * sm->dma.ifragptr;
193 else {
194 p = (unsigned char *)sm->dma.ibuf + NUM_FRAGMENTS * sm->dma.ifragsz;
195 memcpy(p, sm->dma.ibuf, sm->dma.ifragsz);
196 }
197 if (sm->dma.o16bit) {
198 time_exec(sm->debug_vals.demod_cyc,
199 sm->mode_rx->demodulator_s16(sm, p, sm->dma.ifragsz/2));
200 } else {
201 time_exec(sm->debug_vals.demod_cyc,
202 sm->mode_rx->demodulator_u8(sm, p, sm->dma.ifragsz));
203 }
204 sm->dma.ifragptr = (sm->dma.ifragptr + 1) % NUM_FRAGMENTS;
205 }
206 }
207
208 extern __inline__ void dma_init_receive(struct sm_state *sm)
209 {
210 sm->dma.ifragptr = 0;
211 }
212
213 /* --------------------------------------------------------------------- */
214 #endif /* _SMDMA_H */
215
216
217
218