[Letux-kernel] [PATCH] mtd: onenand: omap2: Pass correct flags for prep_dma_memcpy

[H. Nikolaus Schaller]

Hi Andreas,
I think we never would have found this ourselves...

With this OneNAND issue fixed I think we can now better analyse why the 1GHz OPP is no longer working reliable if we do not revert Tony's upstream patch.

BR,
Nikolaus



> Am 04.01.2020 um 09:46 schrieb H. Nikolaus Schaller <hns at goldelico.com>:
> 
> 
>> Am 04.01.2020 um 08:34 schrieb Peter Ujfalusi <peter.ujfalusi at ti.com>:
>> 
>> The commit converting the driver to DMAengine was missing the flags for
>> the memcpy prepare call.
>> It went unnoticed since the omap-dma drive was ignoring them.
> 
> s/drive/driver/
> 
>> 
>> Fixes: 3ed6a4d1de2c5 (" mtd: onenand: omap2: Convert to use dmaengine for memcp")
>> Reported-by: Aaro Koskinen <aaro.koskinen at iki.fi>
>> Signed-off-by: Peter Ujfalusi <peter.ujfalusi at ti.com>
>> ---
>> Hi,
>> 
>> Aaro reported [1] a failure on omap2-onenand pointing to
>> 4689d35c765c696bdf0535486a990038b242a26b. It looks like the root cause is the
>> conversion of omap2-onenand to DMAengine which missed the flags.
>> 
>> Basically the client is waiting for a callback without asking for it. This
>> certainly causes timeout.
>> 
>> I have not tested the patch, but it should fix the issue.
> 
> makes the gta04a5one.dts work again.
> 
> Tested-by: H. Nikolaus Schaller <hns at goldelico.com>
> 
> BR and thanks!
> Nikolaus
> 
>> 
>> [1] https://lore.kernel.org/lkml/20200103081726.GD15023@darkstar.musicnaut.iki.fi/
>> 
>> drivers/mtd/nand/onenand/omap2.c | 3 ++-
>> 1 file changed, 2 insertions(+), 1 deletion(-)
>> 
>> diff --git a/drivers/mtd/nand/onenand/omap2.c b/drivers/mtd/nand/onenand/omap2.c
>> index edf94ee54ec7..71a632b815aa 100644
>> --- a/drivers/mtd/nand/onenand/omap2.c
>> +++ b/drivers/mtd/nand/onenand/omap2.c
>> @@ -328,7 +328,8 @@ static inline int omap2_onenand_dma_transfer(struct omap2_onenand *c,
>> 	struct dma_async_tx_descriptor *tx;
>> 	dma_cookie_t cookie;
>> 
>> -	tx = dmaengine_prep_dma_memcpy(c->dma_chan, dst, src, count, 0);
>> +	tx = dmaengine_prep_dma_memcpy(c->dma_chan, dst, src, count,
>> +				       DMA_CTRL_ACK | DMA_PREP_INTERRUPT);
>> 	if (!tx) {
>> 		dev_err(&c->pdev->dev, "Failed to prepare DMA memcpy\n");
>> 		return -EIO;
>> -- 
>> Peter
>> 
>> Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
>> Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki
>> 
>