On 10-07-18, 17:45, Paul Cercueil wrote: > > > Le lun. 9 juil. 2018 à 19:14, Vinod <vkoul@xxxxxxxxxx> a écrit : > > On 03-07-18, 14:32, Paul Cercueil wrote: > > > The JZ4725B has one DMA core starring six DMA channels. > > > As for the JZ4770, each DMA channel's clock can be enabled with > > > a register write, the difference here being that once started, it > > > is not possible to turn it off. > > > > ok so disable for this, right.. > > > > > @@ -204,6 +205,8 @@ static inline void > > > jz4780_dma_chan_enable(struct jz4780_dma_dev *jzdma, > > > { > > > if (jzdma->version == ID_JZ4770) > > > jz4780_dma_ctrl_writel(jzdma, JZ_DMA_REG_DCKES, BIT(chn)); > > > + else if (jzdma->version == ID_JZ4725B) > > > + jz4780_dma_ctrl_writel(jzdma, JZ_DMA_REG_DCKE, BIT(chn)); > > > > but you are writing to a different register here.. > > Yes. SoCs >= JZ4770 have the DCKE read-only register, and DCKES/DCKEC to > set/clear bits in DCKE. > On JZ4725B, DCKE is read/write, but the zeros written are ignored (at least > that's what the > documentation says). and that was not documented in the log... so i though it maybe a typo. -- ~Vinod -- To unsubscribe from this list: send the line "unsubscribe dmaengine" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html