> -----Original Message----- > From: Vinod [mailto:vkoul@xxxxxxxxxx] > Sent: 2018年7月10日 23:33 > To: Robin Gong <yibin.gong@xxxxxxx> > Cc: dan.j.williams@xxxxxxxxx; shawnguo@xxxxxxxxxx; > s.hauer@xxxxxxxxxxxxxx; Fabio Estevam <fabio.estevam@xxxxxxx>; > linux@xxxxxxxxxxxxxxx; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; > kernel@xxxxxxxxxxxxxx; dmaengine@xxxxxxxxxxxxxxx; > linux-kernel@xxxxxxxxxxxxxxx; dl-linux-imx <linux-imx@xxxxxxx> > Subject: Re: [PATCH v1 3/4] dmaengine: imx-sdma: support dmatest > > On 11-07-18, 00:23, Robin Gong wrote: > > dmatest(memcpy) will never call dmaengine_slave_config before prep, > > and that should have been a hint to you that you should not expect that > > > so jobs in dmaengine_slave_config need to be moved into somewhere > > before device_prep_dma_memcpy. Besides, dmatest never setup chan > > ->private as other common case like uart/audio/spi will always setup > > chan->private. Here check it to judge if it's dmatest case and do > > jobs in slave_config. > > and you should not do anything for dmatest. Supporting it means memcpy > implementation is not correct :) Okay, I will any word about dmatest here since memcpy assume no calling slave_config. > > > > > Signed-off-by: Robin Gong <yibin.gong@xxxxxxx> > > --- > > drivers/dma/imx-sdma.c | 37 ++++++++++++++++++++++++++++--------- > > 1 file changed, 28 insertions(+), 9 deletions(-) > > > > diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c index > > ed2267d..48f3749 100644 > > --- a/drivers/dma/imx-sdma.c > > +++ b/drivers/dma/imx-sdma.c > > @@ -1222,10 +1222,36 @@ static int sdma_alloc_chan_resources(struct > > dma_chan *chan) { > > struct sdma_channel *sdmac = to_sdma_chan(chan); > > struct imx_dma_data *data = chan->private; > > + struct imx_dma_data default_data; > > int prio, ret; > > > > - if (!data) > > - return -EINVAL; > > + ret = clk_enable(sdmac->sdma->clk_ipg); > > + if (ret) > > + return ret; > > + ret = clk_enable(sdmac->sdma->clk_ahb); > > + if (ret) > > + goto disable_clk_ipg; > > + /* > > + * dmatest(memcpy) will never call dmaengine_slave_config before prep, > > + * so jobs in dmaengine_slave_config need to be moved into somewhere > > + * before device_prep_dma_memcpy. Besides, dmatest never setup chan > > + * ->private as other common cases like uart/audio/spi will setup > > + * chan->private always. Here check it to judge if it's dmatest case > > + * and do jobs in slave_config. > > + */ > > + if (!data) { > > + dev_warn(sdmac->sdma->dev, "dmatest is running?\n"); > > why is that a warning! Current SDMA driver assume filter function to set chan->private with specific data (struct imx_dma_data dma_data)like below (sound/soc/fsl/fsl_asrc_dma.c): static bool filter(struct dma_chan *chan, void *param) { if (!imx_dma_is_general_purpose(chan)) return false; chan->private = param; return true; } But in memcpy case, at lease dmatest case, no chan->private set in its filter function. So here take dmatest a special case and do some prepare jobs for memcpy. But if the Upper device driver call dma_request_channel() with their specific filter without 'chan->private' setting in the future. The warning message is a useful hint to them to Add 'chan->private' in filter function. Or doc it somewhere? > > > + sdmac->word_size = sdmac->sdma->dma_device.copy_align; > > + default_data.priority = 2; > > + default_data.peripheral_type = IMX_DMATYPE_MEMORY; > > + default_data.dma_request = 0; > > + default_data.dma_request2 = 0; > > + data = &default_data; > > + > > + sdma_config_ownership(sdmac, false, true, false); > > + sdma_get_pc(sdmac, IMX_DMATYPE_MEMORY); > > + sdma_load_context(sdmac); > > + } > > this needs to be default for memcpy > > -- > ~Vinod ?韬{.n?????%??檩??w?{.n???Ё?撖)?骅w* jg????????G??⒏ ⒎?:+v???????? ????＂??????
