Hello Mr.BIn,

I tested using the latest u-boot (u-boot-2016.07-rc1) with CONFIG_GENERATE_ACPI_TABLE=y enabled. I am still facing the same issue, the Linux kernel is not able to initialize the root file system from the sd card. I have attached the logs for your reference.

My Analysis: [ 1.267312] sdhci-pci 0000:00:12.0: failed to setup card detect gpio -- this error message I am seeing with UEFI firmware also. So I am assuming it is not the issue here.

I have done some debugging of MMC initialisation and found that in mmc_rescan function (drivers/mmc/core/core.c)

host->ops->get_cd(host) returns 0

and the condition is failed. So MMC is not getting intialized. i checked the return of

!!(sdhci_readl(host, SDHCI_PRESENT_STATE) & SDHCI_CARD_PRESENT); and here I am seeing that

with U-boot version it is 1FA0000 and bit AND with 0x00010000 is zero (condition fails) with UEFI version it is 1FF0000 and bit AND with 0x00010000 is one (condition succeeded)

Do you have any idea why this is happening, any input from your side will help me

Thanks a lot:)

Mit Freundlichen Grüßen VinothKumar +49 1798909072

On Tue, Jun 7, 2016 at 11:43 AM, Bin Meng bmeng.cn@gmail.com wrote:

Hi,

On Tue, Jun 7, 2016 at 2:09 PM, vinoth eswaran evinoth1206@gmail.com wrote:

...

Hello Mr.Bin,

Please keep the ML in the loop, also avoid top-posting, and always use plain text.

...

I have attached the start up logs for your reference, I have added some debug messages also and I have disabled the SDIO (0f15) by removing it from u-boot , so please ignore that.

bootcmd=fatload mmc 0:1 01000000 bzImage; zboot 01000000

I am not passing any commnd line from u-boot.

Since I have builded a customised Linux kernel I have the command line added in one of the .scc files.

Kernel command line: root=/dev/mmcblk0p2 rootwait rootfstype=ext4 console=ttyS0,115200 console=tty0

My View:

By UEFI SDHCI is on ACPI

mmc0: SDHCI controller on ACPI [80860F16:00] using ADMA

and by u-boot SDHCI is on PCI

mmc0: SDHCI controller on PCI [0000:00:12.0] using ADMA

and I think that something is missing in U-boot or Linux , so it is unable to initialize SD card. It will be great , if u give me some inputs to fix this issue.

Just some initial investigation based on your log. It looks Linux kernel prints:

[ 1.267312] sdhci-pci 0000:00:12.0: failed to setup card detect gpio

where it calls mmc_gpiod_request_cd() in drivers/mmc/host/sdhci-pci-core.c:

mmc_gpiod_request_cd(host->mmc, slot->cd_con_id, slot->cd_idx, slot->cd_override_level, 0, NULL)) { dev_warn(&pdev->dev, "failed to setup card detect gpio\n"); slot->cd_idx = -1; }

I did not have time to debug this, but based on the API name it looks to me this mmc_gpiod_request_cd() has something to do with GPIO where the Linux SDHC driver requests a card detect signal from a GPIO pin.

On BayTrail, GPIO driver in Linux only works with ACPI as it cannot be discovered via PCI, so U-Boot must ship with an ACPI table, which is already supported in the latest mainline. Please do the same testing with the latest U-Boot to see if the problem still exists.

Regards, Bin