Hi Adrian, thanks for the feedbacks. On Tue, Jul 02, 2019 at 12:10:44PM +0300, Adrian Hunter wrote: > On 16/06/19 11:48 PM, Angelo Dureghello wrote: > > Some controller as the ColdFire eshdc may require an endianness > > byte swap, because DMA read endianness is not configurable. > > I would prefer something more generic, like adding another callback > for ->request_done() e.g. > > > diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c > index f56ae6f153d4..a63e528cb885 100644 > --- a/drivers/mmc/host/sdhci.c > +++ b/drivers/mmc/host/sdhci.c > @@ -2729,7 +2729,10 @@ static bool sdhci_request_done(struct sdhci_host *host) > > spin_unlock_irqrestore(&host->lock, flags); > > - mmc_request_done(host->mmc, mrq); > + if (host->ops->request_done) > + host->ops->request_done(host, mrq); > + else > + mmc_request_done(host->mmc, mrq); > > return false; > } > > > Then you can use the ->request_done() callback to iterate over the data->sg > and make byte-swaps as needed. > Ok, good to know, will try. > > > > Signed-off-by: Angelo Dureghello <angelo@xxxxxxxx> > > --- > > drivers/mmc/host/sdhci.c | 19 +++++++++++++++++++ > > drivers/mmc/host/sdhci.h | 7 +++++++ > > 2 files changed, 26 insertions(+) > > > > diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c > > index 59acf8e3331e..f56ae6f153d4 100644 > > --- a/drivers/mmc/host/sdhci.c > > +++ b/drivers/mmc/host/sdhci.c > > @@ -2600,6 +2600,18 @@ static const struct mmc_host_ops sdhci_ops = { > > .card_busy = sdhci_card_busy, > > }; > > > > +static void sdhci_be_to_le(char *buff, u32 length) > > +{ > > + int i, size = length >> 2; > > + u32 *buffer = (u32 *)buff; > > + u32 temp; > > + > > + for (i = 0; i < size; i++) { > > + temp = *buffer; > > + *buffer++ = __le32_to_cpu(temp); > > + } > > +} > > + > > /*****************************************************************************\ > > * * > > * Request done * > > @@ -2655,6 +2667,13 @@ static bool sdhci_request_done(struct sdhci_host *host) > > host->bounce_addr, > > host->bounce_buffer_size, > > DMA_FROM_DEVICE); > > + > > + if (host->quirks2 & > > + SDHCI_QUIRK2_USE_32BIT_BE_DMA_SWAP) > > + sdhci_be_to_le( > > + host->bounce_buffer, > > + length); > > + > > sg_copy_from_buffer(data->sg, > > data->sg_len, > > host->bounce_buffer, > > diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h > > index 199712e7adbb..be08ff1a8c6f 100644 > > --- a/drivers/mmc/host/sdhci.h > > +++ b/drivers/mmc/host/sdhci.h > > @@ -482,6 +482,13 @@ struct sdhci_host { > > */ > > #define SDHCI_QUIRK2_USE_32BIT_BLK_CNT (1<<18) > > > > +/* > > + * On some architectures, as ColdFire/m68k, native endianness is big endian, > > + * and the dma buffer is filled in big endian order only (no other options). > > + * So, a swap is needed for these specific cases. > > + */ > > +#define SDHCI_QUIRK2_USE_32BIT_BE_DMA_SWAP (1<<19) > > + > > int irq; /* Device IRQ */ > > void __iomem *ioaddr; /* Mapped address */ > > char *bounce_buffer; /* For packing SDMA reads/writes */ > > > Reagrds, Angelo