2 * Copyright © 2009 Keith Packard <keithp@keithp.com>
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.
9 * This program is distributed in the hope that it will be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * General Public License for more details.
14 * You should have received a copy of the GNU General Public License along
15 * with this program; if not, write to the Free Software Foundation, Inc.,
16 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
24 * The config address for DMA0 is programmed
25 * separately from that of DMA1-4, but for simplicity,
26 * we make them all contiguous.
29 static __xdata struct cc_dma_channel ao_dma_config[NUM_DMA];
30 static __xdata uint8_t * __xdata ao_dma_done[NUM_DMA];
31 static __data uint8_t ao_next_dma;
34 ao_dma_alloc(__xdata uint8_t *done)
38 if (ao_next_dma == NUM_DMA)
39 ao_panic(AO_PANIC_DMA);
41 ao_dma_done[id] = done;
43 /* When the first dma object is allocated, set up the DMA
50 DMA0CFGH = ((uint16_t) (&ao_dma_config[0])) >> 8;
51 DMA0CFGL = ((uint16_t) (&ao_dma_config[0]));
52 DMA1CFGH = ((uint16_t) (&ao_dma_config[1])) >> 8;
53 DMA1CFGL = ((uint16_t) (&ao_dma_config[1]));
60 ao_dma_set_transfer(uint8_t id,
61 void __xdata *srcaddr,
62 void __xdata *dstaddr,
67 if (DMAARM & (1 << id))
68 ao_panic(AO_PANIC_DMA);
69 ao_dma_config[id].src_high = ((uint16_t) srcaddr) >> 8;
70 ao_dma_config[id].src_low = ((uint16_t) srcaddr);
71 ao_dma_config[id].dst_high = ((uint16_t) dstaddr) >> 8;
72 ao_dma_config[id].dst_low = ((uint16_t) dstaddr);
73 ao_dma_config[id].len_high = count >> 8;
74 ao_dma_config[id].len_low = count;
75 ao_dma_config[id].cfg0 = cfg0;
76 ao_dma_config[id].cfg1 = cfg1 | DMA_CFG1_IRQMASK;
79 #define nop() __asm nop __endasm;
82 ao_dma_start(uint8_t id)
84 uint8_t mask = (1 << id);
88 nop(); nop(); nop(); nop();
89 nop(); nop(); nop(); nop();
91 *(ao_dma_done[id]) = 0;
93 nop(); nop(); nop(); nop();
94 nop(); nop(); nop(); nop();
99 ao_dma_trigger(uint8_t id)
105 ao_dma_abort(uint8_t id)
107 uint8_t mask = (1 << id);
108 DMAARM = 0x80 | mask;
113 ao_dma_isr(void) __interrupt 8
117 /* Find the first DMA channel which is done */
119 for (id = 0; id < ao_next_dma; id++) {
121 /* Clear CPU interrupt flag */
123 /* Clear the completed ID */
125 *(ao_dma_done[id]) = 1;
126 ao_wakeup(ao_dma_done[id]);