Re: [PATCH 1/2] mmc: sdhci: Add support for O2 eMMC HS200 mode

[Adrian Hunter <adrian.hunter@intel.com>]

On 17/01/18 03:37, ernest.zhang wrote:
> when eMMC used as boot device, the eMMC signaling voltage is tied to 1.8v
> fixed output voltage, bios can set o2 sd host controller PCI configuration
> register 0x308 bit4 to 1 to let host controller skip try 3.3.v signaling
> voltage and direct use 1.8v singling voltage in eMMC initialize process.
> 
> Signed-off-by: ernest.zhang <ernest.zhang@bayhubtech.com>

Please use version numbers in the patch subject.  This was V3, the next is
V4. A summary of what has changed (after the --- line or in the cover email)
is also expected.

> ---
>  drivers/mmc/host/sdhci-pci-o2micro.c | 20 +++++++++++++++++++-
>  1 file changed, 19 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/mmc/host/sdhci-pci-o2micro.c b/drivers/mmc/host/sdhci-pci-o2micro.c
> index 555970a29c94..8855a416ffd4 100644
> --- a/drivers/mmc/host/sdhci-pci-o2micro.c
> +++ b/drivers/mmc/host/sdhci-pci-o2micro.c
> @@ -1,8 +1,9 @@
>  /*
> - * Copyright (C) 2013 BayHub Technology Ltd.
> + * Copyright (C) 2018 BayHub Technology Ltd.
>   *
>   * Authors: Peter Guo <peter.guo@bayhubtech.com>
>   *          Adam Lee <adam.lee@canonical.com>
> + *          Ernest Zhang <ernest.zhang@canonical.com>
>   *
>   * This software is licensed under the terms of the GNU General Public
>   * License version 2, as published by the Free Software Foundation, and
> @@ -39,6 +40,7 @@
>  #define O2_SD_MISC_CTRL4	0xFC
>  #define O2_SD_TUNING_CTRL	0x300
>  #define O2_SD_PLL_SETTING	0x304
> +#define O2_SD_MISC_SETTING	0x308
>  #define O2_SD_CLK_SETTING	0x328
>  #define O2_SD_CAP_REG2		0x330
>  #define O2_SD_CAP_REG0		0x334
> @@ -53,6 +55,7 @@
>  
>  #define O2_SD_VENDOR_SETTING	0x110
>  #define O2_SD_VENDOR_SETTING2	0x1C8
> +#define O2_SD_HW_TUNING_ENABLE	BIT(4)

This is not used in this patch which means it should be in the other patch

>  
>  static void o2_pci_set_baseclk(struct sdhci_pci_chip *chip, u32 value)
>  {
> @@ -184,6 +187,7 @@ int sdhci_pci_o2_probe_slot(struct sdhci_pci_slot *slot)
>  	struct sdhci_pci_chip *chip;
>  	struct sdhci_host *host;
>  	u32 reg;
> +	int ret;
>  
>  	chip = slot->chip;
>  	host = slot->host;
> @@ -197,6 +201,20 @@ int sdhci_pci_o2_probe_slot(struct sdhci_pci_slot *slot)
>  		if (reg & 0x1)
>  			host->quirks |= SDHCI_QUIRK_MULTIBLOCK_READ_ACMD12;
>  
> +		if (chip->pdev->device == PCI_DEVICE_ID_O2_SEABIRD0) {
> +			ret = pci_read_config_dword(chip->pdev,
> +						    O2_SD_MISC_SETTING, &reg);
> +			if (ret)
> +				return -EIO;
> +			if (reg & (1 << 4)) {
> +				pr_info("%s: emmc 1.8v flag is set, force 1.8v signaling voltage\n",
> +				     mmc_hostname(host->mmc));
> +				host->flags &= ~SDHCI_SIGNALING_330;
> +				host->flags |= SDHCI_SIGNALING_180;
> +			}
> +		}
> +
> +

Please do not add double blank line

>  		if (chip->pdev->device != PCI_DEVICE_ID_O2_FUJIN2)
>  			break;
>  		/* set dll watch dog timer */
>