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@xxxxxxxxxxxxxx>
---
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@xxxxxxxxxxxxxx>
* Adam Lee <adam.lee@xxxxxxxxxxxxx>
+ * Ernest Zhang <ernest.zhang@xxxxxxxxxxxxx>
*
* 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
--
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