ASoC: AMD: Do not generate interrups for every captured sample
authorDaniel Kurtz <djkurtz@chromium.org>
Mon, 2 Jul 2018 21:19:54 +0000 (15:19 -0600)
committerMark Brown <broonie@kernel.org>
Tue, 3 Jul 2018 15:14:31 +0000 (16:14 +0100)
On capture, audio data is first copied from I2S to ACP memory, and then
from ACP to SYSRAM.  The I2S_TO_ACP_DMA interrupt fires on every sample
transferred from I2S to ACP memory.  That is it fires ~48000 times per
second when capturing @ 48 kHz.  Since we don't do anything on this
interrupt anyway, disable it to save quite a few unnecessary interrupts.
The real "work" (calling snd_pcm_period_elapsed()) is done when transfer
from ACP to SYSRAM is complete.

Signed-off-by: Daniel Kurtz <djkurtz@chromium.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
sound/soc/amd/acp-pcm-dma.c

index df53412967e1713b5789621591b308d9869aca6c..cd4d2520ac14498cecbaf836d48b2400a2795e71 100644 (file)
@@ -412,10 +412,8 @@ static void acp_dma_start(void __iomem *acp_mmio, u16 ch_num)
        switch (ch_num) {
        case ACP_TO_I2S_DMA_CH_NUM:
        case ACP_TO_SYSRAM_CH_NUM:
-       case I2S_TO_ACP_DMA_CH_NUM:
        case ACP_TO_I2S_DMA_BT_INSTANCE_CH_NUM:
        case ACP_TO_SYSRAM_BT_INSTANCE_CH_NUM:
-       case I2S_TO_ACP_DMA_BT_INSTANCE_CH_NUM:
                dma_ctrl |= ACP_DMA_CNTL_0__DMAChIOCEn_MASK;
                break;
        default:
@@ -704,12 +702,6 @@ static irqreturn_t dma_irq_handler(int irq, void *arg)
                              acp_mmio, mmACP_EXTERNAL_INTR_STAT);
        }
 
-       if ((intr_flag & BIT(I2S_TO_ACP_DMA_CH_NUM)) != 0) {
-               valid_irq = true;
-               acp_reg_write((intr_flag & BIT(I2S_TO_ACP_DMA_CH_NUM)) << 16,
-                             acp_mmio, mmACP_EXTERNAL_INTR_STAT);
-       }
-
        if ((intr_flag & BIT(ACP_TO_SYSRAM_BT_INSTANCE_CH_NUM)) != 0) {
                valid_irq = true;
                snd_pcm_period_elapsed(irq_data->capture_i2sbt_stream);
@@ -718,13 +710,6 @@ static irqreturn_t dma_irq_handler(int irq, void *arg)
                              acp_mmio, mmACP_EXTERNAL_INTR_STAT);
        }
 
-       if ((intr_flag & BIT(I2S_TO_ACP_DMA_BT_INSTANCE_CH_NUM)) != 0) {
-               valid_irq = true;
-               acp_reg_write((intr_flag &
-                             BIT(I2S_TO_ACP_DMA_BT_INSTANCE_CH_NUM)) << 16,
-                             acp_mmio, mmACP_EXTERNAL_INTR_STAT);
-       }
-
        if (valid_irq)
                return IRQ_HANDLED;
        else