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 <[email protected]> --- 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 <[email protected]> * Adam Lee <[email protected]> + * Ernest Zhang <[email protected]> * * 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) 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, ®); + 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; + } + } + + if (chip->pdev->device != PCI_DEVICE_ID_O2_FUJIN2) break; /* set dll watch dog timer */ -- 2.14.1
