Hi Konrad, konrad.dybcio@xxxxxxxxxxxxxx wrote on Thu, 13 Jan 2022 19:44:26 +0100: > While I have absolutely 0 idea why and how, running clear_bam_transaction > when READID is issued makes the DMA totally clog up and refuse to function > at all on mdm9607. In fact, it is so bad that all the data gets garbled > and after a short while in the nand probe flow, the CPU decides that > sepuku is the only option. > > Removing _READID from the if condition makes it work like a charm, I can > read data and mount partitions without a problem. > > Signed-off-by: Konrad Dybcio <konrad.dybcio@xxxxxxxxxxxxxx> > --- > This is totally just an observation which took me an inhumane amount of > debug prints to find.. perhaps there's a better reason behind this, but > I can't seem to find any answers.. Therefore, this is a BIG RFC! I'm adding two people from codeaurora who worked a lot on this driver. Hopefully they will have an idea :) Thanks,Miquèl > > > drivers/mtd/nand/raw/qcom_nandc.c | 3 +-- > 1 file changed, 1 insertion(+), 2 deletions(-) > > diff --git a/drivers/mtd/nand/raw/qcom_nandc.c b/drivers/mtd/nand/raw/qcom_nandc.c > index 04e6f7b26706..506006ccdf1a 100644 > --- a/drivers/mtd/nand/raw/qcom_nandc.c > +++ b/drivers/mtd/nand/raw/qcom_nandc.c > @@ -1459,8 +1459,7 @@ static void pre_command(struct qcom_nand_host *host, int command) > > clear_read_regs(nandc); > > - if (command == NAND_CMD_RESET || command == NAND_CMD_READID || > - command == NAND_CMD_PARAM || command == NAND_CMD_ERASE1) > + if (command == NAND_CMD_RESET || command == NAND_CMD_PARAM || command == NAND_CMD_ERASE1) > clear_bam_transaction(nandc); > } >
