wandboard / imx6 / exynos4 / cortex-a9 "wrong-endian bug" fixed

[Bernd Walter]

Am 12.02.2014 um 23:37 schrieb Ian Lepore <ian at FreeBSD.org>:

> On Wed, 2014-02-12 at 23:22 +0100, Bernd Walter wrote:
>> On Tue, Feb 11, 2014 at 09:33:29PM -0700, Ian Lepore wrote:
>>> On Tue, 2014-02-11 at 20:54 -0700, Ian Lepore wrote:
>>>> On Tue, 2014-02-11 at 14:44 +0100, Bernd Walter wrote:
>>>>> On Tue, Feb 11, 2014 at 02:07:33AM +0100, Bernd Walter wrote:
>>>>>> I can't seen to get the second microSD-slot running.
>>>>>> The controllers get attached, but mmc only to the onboard slot.
>>>>>> The WiFi is SDIO, which I didn't compile into the kernel and I noticed
>>>>>> there is a GPIO used to enable the chip.
>>>>> 
>>>>> Strange enough the 4th controller gets an mmc1 device attached:
>>>>> sdhci_imx3: <Freescale uSDHC controller> mem 0x219c000-0x219ffff irq 57 on simplebus2
>>>>> sdhci_imx3-slot0: 200MHz HS 4bits 3.3V 3.0V PIO
>>>>> sdhci_imx3-slot0: ============== REGISTER DUMP ==============
>>>>> sdhci_imx3-slot0: Sys addr: 0x00000000 | Version:  0x00000002
>>>>> sdhci_imx3-slot0: Blk size: 0x00000000 | Blk cnt:  0x00000001
>>>>> sdhci_imx3-slot0: Argument: 0x00000000 | Trn mode: 0x00000000
>>>>> sdhci_imx3-slot0: Present:  0xf78d8088 | Host ctl: 0x00000000
>>>>> sdhci_imx3-slot0: Power:    0x0000000d | Blk gap:  0x00000080
>>>>> sdhci_imx3-slot0: Wake-up:  0x00000008 | Clock:    0x00000002
>>>>> sdhci_imx3-slot0: Timeout:  0x00000080 | Int stat: 0x00000000
>>>>> sdhci_imx3-slot0: Int enab: 0x017f00fb | Sig enab: 0x017f00fb
>>>>> sdhci_imx3-slot0: AC12 err: 0x00000000 | Slot int: 0x00000000
>>>>> sdhci_imx3-slot0: Caps:     0x0377c800 | Max curr: 0x80000000
>>>>> sdhci_imx3-slot0: ===========================================
>>>>> mmc1: <MMC/SD bus> on sdhci_imx3
>>>>> 
>>>>> It hangs on probing, but it is my understanding that this controller
>>>>> isn't wired at all on wandboard.
>>>>> But why isn't there an attachment with the other two controllers.
>>>>> 
>>>> 
>>>> I can't get the uSD slot on the carrier board to work either, but my
>>>> symptoms are different.
>>>> 
>>>> Aha!  I just noticed that Freescale moved some bits around in the
>>>> Present State register and defined some that are undefined in the spec
>>>> and so on.  I completely overlooked that when I was writing the
>>>> driver.  
>>>> 
>>>> I need to write some proper translation routines, which ain't happening
>>>> tonight. :)  But, as proof of concept, the attached little crude hack
>>>> makes it successfully probe both of my sd slots now.
>>>> 
>>>> -- Ian
>>>> 
>>>> differences between files attachment (imx_sdhci_detect_hack.diff)
>>>> Index: sys/arm/freescale/imx/imx_sdhci.c
>>>> ===================================================================
>>>> --- sys/arm/freescale/imx/imx_sdhci.c    (revision 261700)
>>>> +++ sys/arm/freescale/imx/imx_sdhci.c    (working copy)
>>>> @@ -298,6 +298,9 @@ imx_sdhci_read_4(device_t dev, struct sdhci_slot *
>>>>        val32 |= sc->r1bfix_intmask;
>>>>    }
>>>> 
>>>> +    if (off == SDHCI_PRESENT_STATE && device_get_unit(dev) != 1)
>>>> +        val32 |= SDHCI_CARD_PRESENT;
>>>> +
>>>>    return val32;
>>>> }
>>>> 
>>> 
>>> Just realized... that check for unit != 1 is only needed if you have the
>>> wifi device enabled in the dts.  If only the sd slots are enabled, leave
>>> that out.
>> 
>> With that both cards are probed now.
>> 
> 
> The bad news is that I've just finished coding up the translation
> between the freescale and standard definitions of the Present State
> register, and the bit for card-detected didn't move.  So it's not fixed
> yet.
> 
> The u-boot code uses gpios for card detect, and the wandboard schematic
> agrees with that.  I have no idea why the sdhci controller thinks one
> slot has a card inserted and the other doesn't.  Maybe there are just
> some internal pads that aren't bonded and it's an accident of how the
> lines are floating.

I will try to make tests on MarSboard soon.
It has an onboard emmc and a slot.
Not sure which controllers they use for which - will have to read schematic first.
> 
> There's a lot (a LOT) of work to be done to get to a proper solution.
> The standard dev/sdhci driver has no concept of how to use a gpio to
> check for card presence, so there's work to be done there.  On the imx6
> side, we have nothing right now for pinmux or gpio support.
> 
> It should also be possible to use the DAT3 line for card detect, I'll
> look into how to make that work.
> 
> -- Ian
> 
>