diff options
Diffstat (limited to 'arch/arm/mach-davinci/dma.c')
| -rw-r--r-- | arch/arm/mach-davinci/dma.c | 67 |
1 files changed, 51 insertions, 16 deletions
diff --git a/arch/arm/mach-davinci/dma.c b/arch/arm/mach-davinci/dma.c index 648fbb760ae1..15dd886df04c 100644 --- a/arch/arm/mach-davinci/dma.c +++ b/arch/arm/mach-davinci/dma.c @@ -226,11 +226,11 @@ struct edma { */ DECLARE_BITMAP(edma_inuse, EDMA_MAX_PARAMENTRY); - /* The edma_noevent bit for each channel is clear unless - * it doesn't trigger DMA events on this platform. It uses a - * bit of SOC-specific initialization code. + /* The edma_unused bit for each channel is clear unless + * it is not being used on this platform. It uses a bit + * of SOC-specific initialization code. */ - DECLARE_BITMAP(edma_noevent, EDMA_MAX_DMACH); + DECLARE_BITMAP(edma_unused, EDMA_MAX_DMACH); unsigned irq_res_start; unsigned irq_res_end; @@ -243,6 +243,7 @@ struct edma { }; static struct edma *edma_info[EDMA_MAX_CC]; +static int arch_num_cc; /* dummy param set used to (re)initialize parameter RAM slots */ static const struct edmacc_param dummy_paramset = { @@ -555,8 +556,27 @@ static int reserve_contiguous_slots(int ctlr, unsigned int id, return EDMA_CTLR_CHAN(ctlr, i - num_slots + 1); } +static int prepare_unused_channel_list(struct device *dev, void *data) +{ + struct platform_device *pdev = to_platform_device(dev); + int i, ctlr; + + for (i = 0; i < pdev->num_resources; i++) { + if ((pdev->resource[i].flags & IORESOURCE_DMA) && + (int)pdev->resource[i].start >= 0) { + ctlr = EDMA_CTLR(pdev->resource[i].start); + clear_bit(EDMA_CHAN_SLOT(pdev->resource[i].start), + edma_info[ctlr]->edma_unused); + } + } + + return 0; +} + /*-----------------------------------------------------------------------*/ +static bool unused_chan_list_done; + /* Resource alloc/free: dma channels, parameter RAM slots */ /** @@ -594,7 +614,22 @@ int edma_alloc_channel(int channel, void *data, enum dma_event_q eventq_no) { - unsigned i, done, ctlr = 0; + unsigned i, done = 0, ctlr = 0; + int ret = 0; + + if (!unused_chan_list_done) { + /* + * Scan all the platform devices to find out the EDMA channels + * used and clear them in the unused list, making the rest + * available for ARM usage. + */ + ret = bus_for_each_dev(&platform_bus_type, NULL, NULL, + prepare_unused_channel_list); + if (ret < 0) + return ret; + + unused_chan_list_done = true; + } if (channel >= 0) { ctlr = EDMA_CTLR(channel); @@ -602,15 +637,15 @@ int edma_alloc_channel(int channel, } if (channel < 0) { - for (i = 0; i < EDMA_MAX_CC; i++) { + for (i = 0; i < arch_num_cc; i++) { channel = 0; for (;;) { channel = find_next_bit(edma_info[i]-> - edma_noevent, + edma_unused, edma_info[i]->num_channels, channel); if (channel == edma_info[i]->num_channels) - return -ENOMEM; + break; if (!test_and_set_bit(channel, edma_info[i]->edma_inuse)) { done = 1; @@ -622,6 +657,8 @@ int edma_alloc_channel(int channel, if (done) break; } + if (!done) + return -ENOMEM; } else if (channel >= edma_info[ctlr]->num_channels) { return -EINVAL; } else if (test_and_set_bit(channel, edma_info[ctlr]->edma_inuse)) { @@ -642,7 +679,7 @@ int edma_alloc_channel(int channel, map_dmach_queue(ctlr, channel, eventq_no); - return channel; + return EDMA_CTLR_CHAN(ctlr, channel); } EXPORT_SYMBOL(edma_alloc_channel); @@ -1219,7 +1256,7 @@ int edma_start(unsigned channel) unsigned int mask = (1 << (channel & 0x1f)); /* EDMA channels without event association */ - if (test_bit(channel, edma_info[ctlr]->edma_noevent)) { + if (test_bit(channel, edma_info[ctlr]->edma_unused)) { pr_debug("EDMA: ESR%d %08x\n", j, edma_shadow0_read_array(ctlr, SH_ESR, j)); edma_shadow0_write_array(ctlr, SH_ESR, j, mask); @@ -1344,7 +1381,6 @@ static int __init edma_probe(struct platform_device *pdev) const s8 (*queue_tc_mapping)[2]; int i, j, found = 0; int status = -1; - const s8 *noevent; int irq[EDMA_MAX_CC] = {0, 0}; int err_irq[EDMA_MAX_CC] = {0, 0}; struct resource *r[EDMA_MAX_CC] = {NULL}; @@ -1407,11 +1443,9 @@ static int __init edma_probe(struct platform_device *pdev) memcpy_toio(edmacc_regs_base[j] + PARM_OFFSET(i), &dummy_paramset, PARM_SIZE); - noevent = info[j].noevent; - if (noevent) { - while (*noevent != -1) - set_bit(*noevent++, edma_info[j]->edma_noevent); - } + /* Mark all channels as unused */ + memset(edma_info[j]->edma_unused, 0xff, + sizeof(edma_info[j]->edma_unused)); sprintf(irq_name, "edma%d", j); irq[j] = platform_get_irq_byname(pdev, irq_name); @@ -1467,6 +1501,7 @@ static int __init edma_probe(struct platform_device *pdev) edma_write_array2(j, EDMA_DRAE, i, 1, 0x0); edma_write_array(j, EDMA_QRAE, i, 0x0); } + arch_num_cc++; } if (tc_errs_handled) { |