From mboxrd@z Thu Jan 1 00:00:00 1970 From: Shawn Lin Subject: [PATCH v4 10/10] ASoC: rockchip_i2s: modify DMA max burst to 1 Date: Sun, 6 Sep 2015 09:13:28 +0800 Message-ID: <1441502008-14116-1-git-send-email-shawn.lin@rock-chips.com> References: <1441501881-13700-1-git-send-email-shawn.lin@rock-chips.com> Cc: Doug Anderson , Olof Johansson , Sonny Rao , Addy Ke , dmaengine-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-rockchip-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, alsa-devel-K7yf7f+aM1XWsZ/bQMPhNw@public.gmane.org, linux-spi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Yiwei Cai , Shawn Lin , Jianqun Xu , Olof Johansson To: Vinod Koul , Heiko Stuebner , Jaroslav Kysela , Takashi Iwai , Mark Brown Return-path: In-Reply-To: <1441501881-13700-1-git-send-email-shawn.lin-TNX95d0MmH7DzftRWevZcw@public.gmane.org> Sender: linux-spi-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: From: Yiwei Cai Test with command - arecord -D hw:0,0 /tmp/a.wav, there are the error dump: dma-pl330 ffb20000.dma-controller: fill_queue:2251 Bad Desc(7) This error is happening when no a multiple of burst size * burst length are coming in. The root cause is pl330 dma controller on Rockchips' platform cannot support DMAFLUSHP instruction which make dma to flush the req of non-aligned or non-multiple of what we set before. The saftest way is to set dma max burst to 1. Signed-off-by: Yiwei Cai Fixes: 4495c89fc ("ASoC: add driver for Rockchip RK3xxx I2S") Signed-off-by: Shawn Lin cc: Addy Ke cc: Jianqun Xu cc: Heiko Stuebner cc: Olof Johansson cc: Doug Anderson cc: Sonny Rao --- Changes in v4: - use snd_dmaengine_pcm_get_quirks to get quirks Changes in v3: None Changes in v2: None Changes in v1: None sound/soc/rockchip/rockchip_i2s.c | 16 +++++++++++++++- 1 file changed, 15 insertions(+), 1 deletion(-) diff --git a/sound/soc/rockchip/rockchip_i2s.c b/sound/soc/rockchip/rockchip_i2s.c index acb5be5..b06e08a 100644 --- a/sound/soc/rockchip/rockchip_i2s.c +++ b/sound/soc/rockchip/rockchip_i2s.c @@ -23,6 +23,8 @@ #define DRV_NAME "rockchip-i2s" +#define ROCKCHIP_I2S_BROKEN_BURST_LEN (1<<0) /* broken burst len */ + struct rk_i2s_dev { struct device *dev; @@ -418,6 +420,7 @@ static int rockchip_i2s_probe(struct platform_device *pdev) struct rk_i2s_dev *i2s; struct resource *res; void __iomem *regs; + int dma_quirk; int ret; i2s = devm_kzalloc(&pdev->dev, sizeof(*i2s), GFP_KERNEL); @@ -460,7 +463,6 @@ static int rockchip_i2s_probe(struct platform_device *pdev) i2s->playback_dma_data.addr = res->start + I2S_TXDR; i2s->playback_dma_data.addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; i2s->playback_dma_data.maxburst = 4; - i2s->capture_dma_data.addr = res->start + I2S_RXDR; i2s->capture_dma_data.addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; i2s->capture_dma_data.maxburst = 4; @@ -489,6 +491,18 @@ static int rockchip_i2s_probe(struct platform_device *pdev) goto err_pcm_register; } + dma_quirk = snd_dmaengine_pcm_get_quirks(&pdev->dev); + if (dma_quirk == ROCKCHIP_I2S_BROKEN_BURST_LEN) { + /* + * Unfortunately, we find broken burst len here, + * just have to limit maxburst to ONE in order to avoid + * non-multiple burst len access fail the dmaengine if + * it can't support flush peripheral function. + */ + i2s->playback_dma_data.maxburst = 1; + i2s->capture_dma_data.maxburst = 1; + } + return 0; err_pcm_register: -- 2.3.7 -- To unsubscribe from this list: send the line "unsubscribe linux-spi" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html