Thanks Adrian. Yes, I did consider adding this ACPI support into sdhci-of-dwcmshc.c, but not sure which one is the preferred way.
Is this (sdhci-of-dwcmshc.c) what you recommend? I'll post the revised changes in patch v2.
> -----Original Message-----
> From: Adrian Hunter <adrian.hunter@xxxxxxxxx>
> Sent: Monday, March 15, 2021 4:34 AM
> To: Liming Sun <limings@xxxxxxxxxx>; Ulf Hansson <ulf.hansson@xxxxxxxxxx>;
> Khalil Blaiech <kblaiech@xxxxxxxxxx>
> Cc: linux-mmc@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx
> Subject: Re: [PATCH v1 1/1] mmc: sdhci-acpi: Add support for NVIDIA
> BlueField-3 SoC
>
> On 12/03/21 3:48 pm, Liming Sun wrote:
> > This commit adds ACPI support for the BlueField-3 SoC which uses
> > the DWC_mshc eMMC controller. The boundary check logic in static
> > function dwcmshc_adma_write_desc() comes from sdhci-of-dwcmshc.c.
>
> Did you consider adding ACPI support to sdhci-of-dwcmshc.c ?
> Other drivers have taken that approach, see sdhci-xenon.c or sdhci-iproc.c
>
> >
> > Signed-off-by: Liming Sun <limings@xxxxxxxxxx>
> > Reviewed-by: Khalil Blaiech <kblaiech@xxxxxxxxxx>
> > ---
> > drivers/mmc/host/sdhci-acpi.c | 64
> +++++++++++++++++++++++++++++++++++++++++++
> > 1 file changed, 64 insertions(+)
> >
> > diff --git a/drivers/mmc/host/sdhci-acpi.c b/drivers/mmc/host/sdhci-acpi.c
> > index 54205e3..6448e94e 100644
> > --- a/drivers/mmc/host/sdhci-acpi.c
> > +++ b/drivers/mmc/host/sdhci-acpi.c
> > @@ -716,6 +716,68 @@ static int sdhci_acpi_emmc_amd_probe_slot(struct
> platform_device *pdev,
> > .priv_size = sizeof(struct amd_sdhci_host),
> > };
> >
> > +/* Check DMA address/length boundary. */
> > +static inline bool dwcmshc_adma_boundary_ok(dma_addr_t addr, int len)
> > +{
> > + return (addr | (SZ_128M - 1)) == ((addr + len - 1) | (SZ_128M - 1));
> > +}
> > +
> > +/*
> > + * If DMA addr spans 128MB boundary, we split the DMA transfer into two
> > + * so that each DMA transfer doesn't exceed the boundary.
> > + */
> > +static void dwcmshc_adma_write_desc(struct sdhci_host *host, void
> **desc,
> > + dma_addr_t addr, int len, unsigned int cmd)
> > +{
> > + int tmplen, offset;
> > +
> > + if (likely(!len || dwcmshc_adma_boundary_ok(addr, len))) {
> > + sdhci_adma_write_desc(host, desc, addr, len, cmd);
> > + return;
> > + }
> > +
> > + offset = addr & (SZ_128M - 1);
> > + tmplen = SZ_128M - offset;
> > + sdhci_adma_write_desc(host, desc, addr, tmplen, cmd);
> > +
> > + addr += tmplen;
> > + len -= tmplen;
> > + sdhci_adma_write_desc(host, desc, addr, len, cmd);
> > +}
> > +
> > +static int sdhci_acpi_emmc_nvda_bf_probe_slot(struct platform_device
> *pdev,
> > + struct acpi_device *adev)
> > +{
> > + struct sdhci_acpi_host *c = platform_get_drvdata(pdev);
> > + struct sdhci_host *host = c->host;
> > + u32 extra;
> > +
> > + /* Extra adma table cnt for cross 128M boundary handling. */
> > + extra = DIV_ROUND_UP_ULL(dma_get_required_mask(&pdev->dev),
> SZ_128M);
> > + extra = min(extra, (u32)SDHCI_MAX_SEGS);
> > + host->adma_table_cnt += extra;
> > +
> > + return 0;
> > +}
> > +
> > +static const struct sdhci_ops sdhci_acpi_ops_nvda_bf = {
> > + .set_clock = sdhci_set_clock,
> > + .set_bus_width = sdhci_set_bus_width,
> > + .set_uhs_signaling = sdhci_set_uhs_signaling,
> > + .reset = sdhci_reset,
> > + .adma_write_desc = dwcmshc_adma_write_desc,
> > +};
> > +
> > +static const struct sdhci_acpi_chip sdhci_acpi_chip_nvda_bf = {
> > + .ops = &sdhci_acpi_ops_nvda_bf,
> > +};
> > +
> > +static const struct sdhci_acpi_slot sdhci_acpi_slot_nvda_bf_emmc = {
> > + .chip = &sdhci_acpi_chip_nvda_bf,
> > + .caps = MMC_CAP_8_BIT_DATA |
> MMC_CAP_NONREMOVABLE,
> > + .probe_slot = sdhci_acpi_emmc_nvda_bf_probe_slot,
> > +};
> > +
> > struct sdhci_acpi_uid_slot {
> > const char *hid;
> > const char *uid;
> > @@ -740,6 +802,7 @@ struct sdhci_acpi_uid_slot {
> > { "QCOM8051", NULL, &sdhci_acpi_slot_qcom_sd_3v },
> > { "QCOM8052", NULL, &sdhci_acpi_slot_qcom_sd },
> > { "AMDI0040", NULL, &sdhci_acpi_slot_amd_emmc },
> > + { "MLNXBF30", NULL, &sdhci_acpi_slot_nvda_bf_emmc },
> > { },
> > };
> >
> > @@ -757,6 +820,7 @@ struct sdhci_acpi_uid_slot {
> > { "QCOM8051" },
> > { "QCOM8052" },
> > { "AMDI0040" },
> > + { "MLNXBF30" },
> > { },
> > };
> > MODULE_DEVICE_TABLE(acpi, sdhci_acpi_ids);
> >
