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-rw-r--r--sound/pci/cs46xx/imgs/cwcdma.asp170
1 files changed, 0 insertions, 170 deletions
diff --git a/sound/pci/cs46xx/imgs/cwcdma.asp b/sound/pci/cs46xx/imgs/cwcdma.asp
deleted file mode 100644
index a65e1193c89a..000000000000
--- a/sound/pci/cs46xx/imgs/cwcdma.asp
+++ /dev/null
@@ -1,170 +0,0 @@
1//
2// Copyright(c) by Benny Sjostrand (benny@hostmobility.com)
3//
4// This program is free software; you can redistribute it and/or modify
5// it under the terms of the GNU General Public License as published by
6// the Free Software Foundation; either version 2 of the License, or
7// (at your option) any later version.
8//
9// This program is distributed in the hope that it will be useful,
10// but WITHOUT ANY WARRANTY; without even the implied warranty of
11// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12// GNU General Public License for more details.
13//
14// You should have received a copy of the GNU General Public License
15// along with this program; if not, write to the Free Software
16// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
17//
18
19
20//
21// This code runs inside the DSP (cs4610, cs4612, cs4624, or cs4630),
22// to compile it you need a tool named SPASM 3.0 and DSP code owned by
23// Cirrus Logic(R). The SPASM program will generate a object file (cwcdma.osp),
24// the "ospparser" tool will genereate the cwcdma.h file it's included from
25// the cs46xx_lib.c file.
26//
27//
28// The purpose of this code is very simple: make it possible to tranfser
29// the samples 'as they are' with no alteration from a PCMreader
30// SCB (DMA from host) to any other SCB. This is useful for AC3 through SPDIF.
31// SRC (source rate converters) task always alters the samples in somehow,
32// however it's from 48khz -> 48khz.
33// The alterations are not audible, but AC3 wont work.
34//
35// ...
36// |
37// +---------------+
38// | AsynchFGTxSCB |
39// +---------------+
40// |
41// subListPtr
42// |
43// +--------------+
44// | DMAReader |
45// +--------------+
46// |
47// subListPtr
48// |
49// +-------------+
50// | PCMReader |
51// +-------------+
52// (DMA from host)
53//
54
55struct dmaSCB
56 {
57 long dma_reserved1[3];
58
59 short dma_reserved2:dma_outBufPtr;
60
61 short dma_unused1:dma_unused2;
62
63 long dma_reserved3[4];
64
65 short dma_subListPtr:dma_nextSCB;
66 short dma_SPBptr:dma_entryPoint;
67
68 long dma_strmRsConfig;
69 long dma_strmBufPtr;
70
71 long dma_reserved4;
72
73 VolumeControl s2m_volume;
74 };
75
76#export DMAReader
77void DMAReader()
78{
79 execChild();
80 r2 = r0->dma_subListPtr;
81 r1 = r0->nextSCB;
82
83 rsConfig01 = r2->strmRsConfig;
84 // Load rsConfig for input buffer
85
86 rsDMA01 = r2->basicReq.daw, , tb = Z(0 - rf);
87 // Load rsDMA in case input buffer is a DMA buffer Test to see if there is any data to transfer
88
89 if (tb) goto execSibling_2ind1 after {
90 r5 = rf + (-1);
91 r6 = r1->dma_entryPoint; // r6 = entry point of sibling task
92 r1 = r1->dma_SPBptr, // r1 = pointer to sibling task's SPB
93 , ind = r6; // Load entry point of sibling task
94 }
95
96 rsConfig23 = r0->dma_strmRsConfig;
97 // Load rsConfig for output buffer (never a DMA buffer)
98
99 r4 = r0->dma_outBufPtr;
100
101 rsa0 = r2->strmBufPtr;
102 // rsa0 = input buffer pointer
103
104 for (i = r5; i >= 0; --i)
105 after {
106 rsa2 = r4;
107 // rsa2 = output buffer pointer
108
109 nop;
110 nop;
111 }
112 //*****************************
113 // TODO: cycles to this point *
114 //*****************************
115 {
116 acc0 = (rsd0 = *rsa0++1);
117 // get sample
118
119 nop; // Those "nop"'s are really uggly, but there's
120 nop; // something with DSP's pipelines which I don't
121 nop; // understand, resulting this code to fail without
122 // having those "nop"'s (Benny)
123
124 rsa0?reqDMA = r2;
125 // Trigger DMA transfer on input stream,
126 // if needed to replenish input buffer
127
128 nop;
129 // Yet another magic "nop" to make stuff work
130
131 ,,r98 = acc0 $+>> 0;
132 // store sample in ALU
133
134 nop;
135 // latency on load register.
136 // (this one is understandable)
137
138 *rsa2++1 = r98;
139 // store sample in output buffer
140
141 nop; // The same story
142 nop; // as above again ...
143 nop;
144 }
145 // TODO: cycles per loop iteration
146
147 r2->strmBufPtr = rsa0,, ;
148 // Update the modified buffer pointers
149
150 r4 = rsa2;
151 // Load output pointer position into r4
152
153 r2 = r0->nextSCB;
154 // Sibling task
155
156 goto execSibling_2ind1 // takes 6 cycles
157 after {
158 r98 = r2->thisSPB:entryPoint;
159 // Load child routine entry and data address
160
161 r1 = r9;
162 // r9 is r2->thisSPB
163
164 r0->dma_outBufPtr = r4,,
165 // Store updated output buffer pointer
166
167 ind = r8;
168 // r8 is r2->entryPoint
169 }
170}