diff options
Diffstat (limited to 'drivers/mmc/host/sdhci-pci.c')
| -rw-r--r-- | drivers/mmc/host/sdhci-pci.c | 83 |
1 files changed, 83 insertions, 0 deletions
diff --git a/drivers/mmc/host/sdhci-pci.c b/drivers/mmc/host/sdhci-pci.c index 7a3fc16d0a6c..6ecd158d8084 100644 --- a/drivers/mmc/host/sdhci-pci.c +++ b/drivers/mmc/host/sdhci-pci.c @@ -20,6 +20,7 @@ #include <linux/slab.h> #include <linux/device.h> #include <linux/mmc/host.h> +#include <linux/mmc/mmc.h> #include <linux/scatterlist.h> #include <linux/io.h> #include <linux/gpio.h> @@ -266,6 +267,69 @@ static void sdhci_pci_int_hw_reset(struct sdhci_host *host) usleep_range(300, 1000); } +static int spt_select_drive_strength(struct sdhci_host *host, + struct mmc_card *card, + unsigned int max_dtr, + int host_drv, int card_drv, int *drv_type) +{ + int drive_strength; + + if (sdhci_pci_spt_drive_strength > 0) + drive_strength = sdhci_pci_spt_drive_strength & 0xf; + else + drive_strength = 1; /* 33-ohm */ + + if ((mmc_driver_type_mask(drive_strength) & card_drv) == 0) + drive_strength = 0; /* Default 50-ohm */ + + return drive_strength; +} + +/* Try to read the drive strength from the card */ +static void spt_read_drive_strength(struct sdhci_host *host) +{ + u32 val, i, t; + u16 m; + + if (sdhci_pci_spt_drive_strength) + return; + + sdhci_pci_spt_drive_strength = -1; + + m = sdhci_readw(host, SDHCI_HOST_CONTROL2) & 0x7; + if (m != 3 && m != 5) + return; + val = sdhci_readl(host, SDHCI_PRESENT_STATE); + if (val & 0x3) + return; + sdhci_writel(host, 0x007f0023, SDHCI_INT_ENABLE); + sdhci_writel(host, 0, SDHCI_SIGNAL_ENABLE); + sdhci_writew(host, 0x10, SDHCI_TRANSFER_MODE); + sdhci_writeb(host, 0xe, SDHCI_TIMEOUT_CONTROL); + sdhci_writew(host, 512, SDHCI_BLOCK_SIZE); + sdhci_writew(host, 1, SDHCI_BLOCK_COUNT); + sdhci_writel(host, 0, SDHCI_ARGUMENT); + sdhci_writew(host, 0x83b, SDHCI_COMMAND); + for (i = 0; i < 1000; i++) { + val = sdhci_readl(host, SDHCI_INT_STATUS); + if (val & 0xffff8000) + return; + if (val & 0x20) + break; + udelay(1); + } + val = sdhci_readl(host, SDHCI_PRESENT_STATE); + if (!(val & 0x800)) + return; + for (i = 0; i < 47; i++) + val = sdhci_readl(host, SDHCI_BUFFER); + t = val & 0xf00; + if (t != 0x200 && t != 0x300) + return; + + sdhci_pci_spt_drive_strength = 0x10 | ((val >> 12) & 0xf); +} + static int byt_emmc_probe_slot(struct sdhci_pci_slot *slot) { slot->host->mmc->caps |= MMC_CAP_8_BIT_DATA | MMC_CAP_NONREMOVABLE | @@ -276,6 +340,10 @@ static int byt_emmc_probe_slot(struct sdhci_pci_slot *slot) slot->hw_reset = sdhci_pci_int_hw_reset; if (slot->chip->pdev->device == PCI_DEVICE_ID_INTEL_BSW_EMMC) slot->host->timeout_clk = 1000; /* 1000 kHz i.e. 1 MHz */ + if (slot->chip->pdev->device == PCI_DEVICE_ID_INTEL_SPT_EMMC) { + spt_read_drive_strength(slot->host); + slot->select_drive_strength = spt_select_drive_strength; + } return 0; } @@ -1203,6 +1271,20 @@ static void sdhci_pci_hw_reset(struct sdhci_host *host) slot->hw_reset(host); } +static int sdhci_pci_select_drive_strength(struct sdhci_host *host, + struct mmc_card *card, + unsigned int max_dtr, int host_drv, + int card_drv, int *drv_type) +{ + struct sdhci_pci_slot *slot = sdhci_priv(host); + + if (!slot->select_drive_strength) + return 0; + + return slot->select_drive_strength(host, card, max_dtr, host_drv, + card_drv, drv_type); +} + static const struct sdhci_ops sdhci_pci_ops = { .set_clock = sdhci_set_clock, .enable_dma = sdhci_pci_enable_dma, @@ -1210,6 +1292,7 @@ static const struct sdhci_ops sdhci_pci_ops = { .reset = sdhci_reset, .set_uhs_signaling = sdhci_set_uhs_signaling, .hw_reset = sdhci_pci_hw_reset, + .select_drive_strength = sdhci_pci_select_drive_strength, }; /*****************************************************************************\ |
