diff options
| -rw-r--r-- | drivers/dma/tegra20-apb-dma.c | 43 |
1 files changed, 38 insertions, 5 deletions
diff --git a/drivers/dma/tegra20-apb-dma.c b/drivers/dma/tegra20-apb-dma.c index efdfffa13349..2c46ac46e7ad 100644 --- a/drivers/dma/tegra20-apb-dma.c +++ b/drivers/dma/tegra20-apb-dma.c @@ -62,6 +62,9 @@ #define TEGRA_APBDMA_STATUS_COUNT_SHIFT 2 #define TEGRA_APBDMA_STATUS_COUNT_MASK 0xFFFC +#define TEGRA_APBDMA_CHAN_CSRE 0x00C +#define TEGRA_APBDMA_CHAN_CSRE_PAUSE (1 << 31) + /* AHB memory address */ #define TEGRA_APBDMA_CHAN_AHBPTR 0x010 @@ -112,10 +115,12 @@ struct tegra_dma; * tegra_dma_chip_data Tegra chip specific DMA data * @nr_channels: Number of channels available in the controller. * @max_dma_count: Maximum DMA transfer count supported by DMA controller. + * @support_channel_pause: Support channel wise pause of dma. */ struct tegra_dma_chip_data { int nr_channels; int max_dma_count; + bool support_channel_pause; }; /* DMA channel registers */ @@ -353,6 +358,32 @@ static void tegra_dma_global_resume(struct tegra_dma_channel *tdc) spin_unlock(&tdma->global_lock); } +static void tegra_dma_pause(struct tegra_dma_channel *tdc, + bool wait_for_burst_complete) +{ + struct tegra_dma *tdma = tdc->tdma; + + if (tdma->chip_data->support_channel_pause) { + tdc_write(tdc, TEGRA_APBDMA_CHAN_CSRE, + TEGRA_APBDMA_CHAN_CSRE_PAUSE); + if (wait_for_burst_complete) + udelay(TEGRA_APBDMA_BURST_COMPLETE_TIME); + } else { + tegra_dma_global_pause(tdc, wait_for_burst_complete); + } +} + +static void tegra_dma_resume(struct tegra_dma_channel *tdc) +{ + struct tegra_dma *tdma = tdc->tdma; + + if (tdma->chip_data->support_channel_pause) { + tdc_write(tdc, TEGRA_APBDMA_CHAN_CSRE, 0); + } else { + tegra_dma_global_resume(tdc); + } +} + static void tegra_dma_stop(struct tegra_dma_channel *tdc) { u32 csr; @@ -408,7 +439,7 @@ static void tegra_dma_configure_for_next(struct tegra_dma_channel *tdc, * If there is already IEC status then interrupt handler need to * load new configuration. */ - tegra_dma_global_pause(tdc, false); + tegra_dma_pause(tdc, false); status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS); /* @@ -418,7 +449,7 @@ static void tegra_dma_configure_for_next(struct tegra_dma_channel *tdc, if (status & TEGRA_APBDMA_STATUS_ISE_EOC) { dev_err(tdc2dev(tdc), "Skipping new configuration as interrupt is pending\n"); - tegra_dma_global_resume(tdc); + tegra_dma_resume(tdc); return; } @@ -429,7 +460,7 @@ static void tegra_dma_configure_for_next(struct tegra_dma_channel *tdc, nsg_req->ch_regs.csr | TEGRA_APBDMA_CSR_ENB); nsg_req->configured = true; - tegra_dma_global_resume(tdc); + tegra_dma_resume(tdc); } static void tdc_start_head_req(struct tegra_dma_channel *tdc) @@ -690,7 +721,7 @@ static void tegra_dma_terminate_all(struct dma_chan *dc) goto skip_dma_stop; /* Pause DMA before checking the queue status */ - tegra_dma_global_pause(tdc, true); + tegra_dma_pause(tdc, true); status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS); if (status & TEGRA_APBDMA_STATUS_ISE_EOC) { @@ -708,7 +739,7 @@ static void tegra_dma_terminate_all(struct dma_chan *dc) sgreq->dma_desc->bytes_transferred += get_current_xferred_count(tdc, sgreq, status); } - tegra_dma_global_resume(tdc); + tegra_dma_resume(tdc); skip_dma_stop: tegra_dma_abort_all(tdc); @@ -1175,6 +1206,7 @@ static void tegra_dma_free_chan_resources(struct dma_chan *dc) static const struct tegra_dma_chip_data tegra20_dma_chip_data = { .nr_channels = 16, .max_dma_count = 1024UL * 64, + .support_channel_pause = false, }; #if defined(CONFIG_OF) @@ -1182,6 +1214,7 @@ static const struct tegra_dma_chip_data tegra20_dma_chip_data = { static const struct tegra_dma_chip_data tegra30_dma_chip_data = { .nr_channels = 32, .max_dma_count = 1024UL * 64, + .support_channel_pause = false, }; static const struct of_device_id tegra_dma_of_match[] __devinitconst = { |