Re: [PATCH v2 14/25] mtd: nand: qcom: add and initialize QPIC DMA resources

[Abhishek Sahu <absahu@codeaurora.org>]

On 2017-08-02 14:11, Archit Taneja wrote:
> On 07/19/2017 05:18 PM, Abhishek Sahu wrote:
>> 1. QPIC NAND uses 3 BAM channels: command, data tx and data
>>     rx while EBI2 NAND uses only single ADM channel.
>> 2. CRCI is only required for ADM DMA and its not required for
> 
> s/its/it's

  I Will fix this.

> 
>>     QPIC NAND.
>> 
>> Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
>> ---
>>   drivers/mtd/nand/qcom_nandc.c | 83 
>> +++++++++++++++++++++++++++++++++----------
>>   1 file changed, 65 insertions(+), 18 deletions(-)
>> 
>> diff --git a/drivers/mtd/nand/qcom_nandc.c 
>> b/drivers/mtd/nand/qcom_nandc.c
>> index 6d24630..cb2b245 100644
>> --- a/drivers/mtd/nand/qcom_nandc.c
>> +++ b/drivers/mtd/nand/qcom_nandc.c
>> @@ -250,9 +250,19 @@ struct qcom_nand_controller {
>>   	struct clk *core_clk;
>>   	struct clk *aon_clk;
>>   -	struct dma_chan *chan;
>> -	unsigned int cmd_crci;
>> -	unsigned int data_crci;
>> +	union {
>> +		struct {
>> +			struct dma_chan *tx_chan;
>> +			struct dma_chan *rx_chan;
>> +			struct dma_chan *cmd_chan;
>> +		};
>> +		struct {
>> +			struct dma_chan *chan;
>> +			unsigned int cmd_crci;
>> +			unsigned int data_crci;
>> +		};
>> +	};
> 
> Could you put comments here explaining one is for EBI2/ADM
> and other is for QPIC/BAM? It'll improve the readability a
> bit. Otherwise:

  Yes that would be better. I will put the comment.

> 
> Reviewed-by: Archit Taneja <architt@codeaurora.org>
> 
> Thanks,
> Archit
> 
>> +
>>   	struct list_head desc_list;
>>     	u8		*data_buffer;
>> @@ -1985,10 +1995,31 @@ static int qcom_nandc_alloc(struct 
>> qcom_nand_controller *nandc)
>>   	if (!nandc->reg_read_buf)
>>   		return -ENOMEM;
>>   -	nandc->chan = dma_request_slave_channel(nandc->dev, "rxtx");
>> -	if (!nandc->chan) {
>> -		dev_err(nandc->dev, "failed to request slave channel\n");
>> -		return -ENODEV;
>> +	if (nandc->props->is_bam) {
>> +		nandc->tx_chan = dma_request_slave_channel(nandc->dev, "tx");
>> +		if (!nandc->tx_chan) {
>> +			dev_err(nandc->dev, "failed to request tx channel\n");
>> +			return -ENODEV;
>> +		}
>> +
>> +		nandc->rx_chan = dma_request_slave_channel(nandc->dev, "rx");
>> +		if (!nandc->rx_chan) {
>> +			dev_err(nandc->dev, "failed to request rx channel\n");
>> +			return -ENODEV;
>> +		}
>> +
>> +		nandc->cmd_chan = dma_request_slave_channel(nandc->dev, "cmd");
>> +		if (!nandc->cmd_chan) {
>> +			dev_err(nandc->dev, "failed to request cmd channel\n");
>> +			return -ENODEV;
>> +		}
>> +	} else {
>> +		nandc->chan = dma_request_slave_channel(nandc->dev, "rxtx");
>> +		if (!nandc->chan) {
>> +			dev_err(nandc->dev,
>> +				"failed to request slave channel\n");
>> +			return -ENODEV;
>> +		}
>>   	}
>>     	INIT_LIST_HEAD(&nandc->desc_list);
>> @@ -2001,7 +2032,19 @@ static int qcom_nandc_alloc(struct 
>> qcom_nand_controller *nandc)
>>     static void qcom_nandc_unalloc(struct qcom_nand_controller *nandc)
>>   {
>> -	dma_release_channel(nandc->chan);
>> +	if (nandc->props->is_bam) {
>> +		if (nandc->tx_chan)
>> +			dma_release_channel(nandc->tx_chan);
>> +
>> +		if (nandc->rx_chan)
>> +			dma_release_channel(nandc->rx_chan);
>> +
>> +		if (nandc->cmd_chan)
>> +			dma_release_channel(nandc->cmd_chan);
>> +	} else {
>> +		if (nandc->chan)
>> +			dma_release_channel(nandc->chan);
>> +	}
>>   }
>>     /* one time setup of a few nand controller registers */
>> @@ -2140,16 +2183,20 @@ static int qcom_nandc_parse_dt(struct 
>> platform_device *pdev)
>>   	struct device_node *np = nandc->dev->of_node;
>>   	int ret;
>>   -	ret = of_property_read_u32(np, "qcom,cmd-crci", &nandc->cmd_crci);
>> -	if (ret) {
>> -		dev_err(nandc->dev, "command CRCI unspecified\n");
>> -		return ret;
>> -	}
>> +	if (!nandc->props->is_bam) {
>> +		ret = of_property_read_u32(np, "qcom,cmd-crci",
>> +					   &nandc->cmd_crci);
>> +		if (ret) {
>> +			dev_err(nandc->dev, "command CRCI unspecified\n");
>> +			return ret;
>> +		}
>>   -	ret = of_property_read_u32(np, "qcom,data-crci", 
>> &nandc->data_crci);
>> -	if (ret) {
>> -		dev_err(nandc->dev, "data CRCI unspecified\n");
>> -		return ret;
>> +		ret = of_property_read_u32(np, "qcom,data-crci",
>> +					   &nandc->data_crci);
>> +		if (ret) {
>> +			dev_err(nandc->dev, "data CRCI unspecified\n");
>> +			return ret;
>> +		}
>>   	}
>>     	return 0;
>> @@ -2199,7 +2246,7 @@ static int qcom_nandc_probe(struct 
>> platform_device *pdev)
>>     	ret = qcom_nandc_alloc(nandc);
>>   	if (ret)
>> -		return ret;
>> +		goto err_core_clk;
>>     	ret = clk_prepare_enable(nandc->core_clk);
>>   	if (ret)
>>