diff options
| author | Keith Packard <keithp@keithp.com> | 2017-02-20 12:12:43 -0800 |
|---|---|---|
| committer | Keith Packard <keithp@keithp.com> | 2017-02-20 12:34:01 -0800 |
| commit | 72ea90d28817549c4343d2fea03a4c951f849cbe (patch) | |
| tree | 58f8c4d06380b4213c1357c7ec1088cfafe95264 /src | |
| parent | 5dc5e2e238f8c1a8ca35d85ec046124afa9385ad (diff) | |
altos/stm: Allow DMA channels to be hijacked by other code
This lets code which needs finer control over DMA to use the channel
without interference, and leaves the DMA engine running so that it can.
Signed-off-by: Keith Packard <keithp@keithp.com>
Diffstat (limited to 'src')
| -rw-r--r-- | src/stm/ao_dma_stm.c | 38 |
1 files changed, 37 insertions, 1 deletions
diff --git a/src/stm/ao_dma_stm.c b/src/stm/ao_dma_stm.c index 63d6688a..962b3acc 100644 --- a/src/stm/ao_dma_stm.c +++ b/src/stm/ao_dma_stm.c @@ -29,7 +29,6 @@ uint8_t ao_dma_done[NUM_DMA]; static struct ao_dma_config ao_dma_config[NUM_DMA]; static uint8_t ao_dma_allocated[NUM_DMA]; static uint8_t ao_dma_mutex[NUM_DMA]; -static uint8_t ao_dma_active; static void ao_dma_isr(uint8_t index) { @@ -49,12 +48,24 @@ ao_dma_isr(uint8_t index) { void stm_dma1_channel1_isr(void) { ao_dma_isr(STM_DMA_INDEX(1)); } void stm_dma1_channel2_isr(void) { ao_dma_isr(STM_DMA_INDEX(2)); } +#ifdef STM_DMA1_3_STOLEN +#define LEAVE_DMA_ON +#else void stm_dma1_channel3_isr(void) { ao_dma_isr(STM_DMA_INDEX(3)); } +#endif void stm_dma1_channel4_isr(void) { ao_dma_isr(STM_DMA_INDEX(4)); } +#ifdef STM_DMA1_5_STOLEN +#define LEAVE_DMA_ON +#else void stm_dma1_channel5_isr(void) { ao_dma_isr(STM_DMA_INDEX(5)); } +#endif void stm_dma1_channel6_isr(void) { ao_dma_isr(STM_DMA_INDEX(6)); } void stm_dma1_channel7_isr(void) { ao_dma_isr(STM_DMA_INDEX(7)); } +#ifndef LEAVE_DMA_ON +static uint8_t ao_dma_active; +#endif + void ao_dma_set_transfer(uint8_t index, volatile void *peripheral, @@ -68,10 +79,12 @@ ao_dma_set_transfer(uint8_t index, ao_dma_mutex[index] = 0xff; } else ao_mutex_get(&ao_dma_mutex[index]); +#ifndef LEAVE_DMA_ON ao_arch_critical( if (ao_dma_active++ == 0) stm_rcc.ahbenr |= (1 << STM_RCC_AHBENR_DMA1EN); ); +#endif stm_dma.channel[index].ccr = ccr | (1 << STM_DMA_CCR_TCIE); stm_dma.channel[index].cndtr = count; stm_dma.channel[index].cpar = peripheral; @@ -96,10 +109,12 @@ void ao_dma_done_transfer(uint8_t index) { stm_dma.channel[index].ccr &= ~(1 << STM_DMA_CCR_EN); +#ifndef LEAVE_DMA_ON ao_arch_critical( if (--ao_dma_active == 0) stm_rcc.ahbenr &= ~(1 << STM_RCC_AHBENR_DMA1EN); ); +#endif if (ao_dma_allocated[index]) ao_dma_mutex[index] = 0; else @@ -120,10 +135,12 @@ ao_dma_dump_cmd(void) { int i; +#ifndef LEAVE_DMA_ON ao_arch_critical( if (ao_dma_active++ == 0) stm_rcc.ahbenr |= (1 << STM_RCC_AHBENR_DMA1EN); ); +#endif printf ("isr %08x ifcr%08x\n", stm_dma.isr, stm_dma.ifcr); for (i = 0; i < NUM_DMA; i++) printf("%d: done %d allocated %d mutex %2d ccr %04x cndtr %04x cpar %08x cmar %08x isr %08x\n", @@ -136,10 +153,12 @@ ao_dma_dump_cmd(void) stm_dma.channel[i].cpar, stm_dma.channel[i].cmar, ao_dma_config[i].isr); +#ifndef LEAVE_DMA_ON ao_arch_critical( if (--ao_dma_active == 0) stm_rcc.ahbenr &= ~(1 << STM_RCC_AHBENR_DMA1EN); ); +#endif } static const struct ao_cmds ao_dma_cmds[] = { @@ -153,7 +172,24 @@ ao_dma_init(void) { int index; +#ifdef LEAVE_DMA_ON + stm_rcc.ahbenr |= (1 << STM_RCC_AHBENR_DMA1EN); +#endif for (index = 0; index < STM_NUM_DMA; index++) { +#if STM_DMA1_5_STOLEN + if (index == STM_DMA_INDEX(5)) { + ao_dma_allocated[index] = 1; + ao_dma_mutex[index] = 0xff; + continue; + } +#endif +#if STM_DMA1_3_STOLEN + if (index == STM_DMA_INDEX(3)) { + ao_dma_allocated[index] = 1; + ao_dma_mutex[index] = 0xff; + continue; + } +#endif stm_nvic_set_enable(STM_ISR_DMA1_CHANNEL1_POS + index); stm_nvic_set_priority(STM_ISR_DMA1_CHANNEL1_POS + index, AO_STM_NVIC_MED_PRIORITY); |