On 27/07/22 06:31, Chevron Li wrote:
> Bayhub chips have better compatibility support for sdr50 than ddr50
Upper case would be better for SDR50 and DDR50
> and both mode have the same R/W performance.
Only if the max frequency is 100 MHz. Is that always the case?
Perhaps comment on that in the commit message.
> Disable ddr50 mode and use sdr50 instead.
Upper case would be better for SDR50 and DDR50
>
> Signed-off-by: Chevron Li<chevron.li@xxxxxxxxxxxxxx>
For neatness, a space before "<" above would be better, and
also a space after ":" in the subject
> ---
> Changes on V1:
> 1.Set quirks2 flag SDHCI_QUIRK2_BROKEN_DDR50 for bayhub chips.
> 2.Use bayhub hardware input tuning for SDR50 mode instead of standard tuning flow.
> ---
> drivers/mmc/host/sdhci-pci-o2micro.c | 7 +++++--
> 1 file changed, 5 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/mmc/host/sdhci-pci-o2micro.c b/drivers/mmc/host/sdhci-pci-o2micro.c
> index 0d4d343dbb77..ad457cd9cbaa 100644
> --- a/drivers/mmc/host/sdhci-pci-o2micro.c
> +++ b/drivers/mmc/host/sdhci-pci-o2micro.c
> @@ -317,11 +317,12 @@ static int sdhci_o2_execute_tuning(struct mmc_host *mmc, u32 opcode)
> u32 reg_val;
>
> /*
> - * This handler only implements the eMMC tuning that is specific to
> + * This handler implements the hardware tuning that is specific to
> * this controller. Fall back to the standard method for other TIMING.
> */
> if ((host->timing != MMC_TIMING_MMC_HS200) &&
> - (host->timing != MMC_TIMING_UHS_SDR104))
> + (host->timing != MMC_TIMING_UHS_SDR104) &&
> + (host->timing != MMC_TIMING_UHS_SDR50))
> return sdhci_execute_tuning(mmc, opcode);
>
> if (WARN_ON((opcode != MMC_SEND_TUNING_BLOCK_HS200) &&
> @@ -631,6 +632,8 @@ static int sdhci_pci_o2_probe_slot(struct sdhci_pci_slot *slot)
> if (reg & 0x1)
> host->quirks |= SDHCI_QUIRK_MULTIBLOCK_READ_ACMD12;
>
> + host->quirks2 |= SDHCI_QUIRK2_BROKEN_DDR50;
> +
> sdhci_pci_o2_enable_msi(chip, host);
>
> if (chip->pdev->device == PCI_DEVICE_ID_O2_SEABIRD0) {
>
> base-commit: 68e77ffbfd06ae3ef8f2abf1c3b971383c866983
