[U-Boot] [PATCH 10/16] usb: xhci: Program 'route string' in the input slot context

Thu Jun 29 05:29:44 UTC 2017

Hi Bin,

On 29.06.2017 01:00, Bin Meng wrote:
> Hi Stefan,
> 
> On Wed, Jun 28, 2017 at 8:27 PM, Bin Meng <bmeng.cn at gmail.com> wrote:
>> Hi Stefan,
>>
>> On Wed, Jun 28, 2017 at 7:28 PM, Stefan Roese <sr at denx.de> wrote:
>>> Hi Bin,
>>>
>>>
>>> On 27.06.2017 10:27, Bin Meng wrote:
>>>>
>>>> Hi Stefan,
>>>>
>>>> On Tue, Jun 27, 2017 at 1:23 PM, Stefan Roese <sr at denx.de> wrote:
>>>>>
>>>>> Hi Bin,
>>>>>
>>>>>
>>>>> On 27.06.2017 02:01, Bin Meng wrote:
>>>>>>
>>>>>>
>>>>>> On Tue, Jun 27, 2017 at 2:07 AM, Marek Vasut <marex at denx.de> wrote:
>>>>>>>
>>>>>>>
>>>>>>> On 06/24/2017 03:57 AM, Bin Meng wrote:
>>>>>>>>
>>>>>>>>
>>>>>>>> Hi Marek,
>>>>>>>>
>>>>>>>> On Sat, Jun 24, 2017 at 2:02 AM, Marek Vasut <marex at denx.de> wrote:
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> On 06/23/2017 11:54 AM, Bin Meng wrote:
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> xHCI spec says: the values of the 'route string' field shall be
>>>>>>>>>> initialized by the first 'Address Device' command issued to a
>>>>>>>>>> device slot, and shall not be modified by any other command.
>>>>>>>>>>
>>>>>>>>>> So far U-Boot does not program this field, and it does not prevent
>>>>>>>>>> SS device directly attached to root port, or HS device behind an HS
>>>>>>>>>> hub, from working, due to the fact that 'route string' is used by
>>>>>>>>>> the xHC to target SS packets. But in order to enumerate devices
>>>>>>>>>> behind an SS hub, this field must be programmed.
>>>>>>>>>>
>>>>>>>>>> With this commit and along with previous commits, now SS & HS
>>>>>>>>>> devices
>>>>>>>>>> attached to a USB 3.0 hub can be enumerated by U-Boot.
>>>>>>>>>>
>>>>>>>>>> As usual, this new feature is only available when DM is on.
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> Great, but I really dislike the ifdef pollution, so this needs to be
>>>>>>>>> sorted out.
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>> The ifdef was needed due to it calls DM APIs or access DM udevice. I
>>>>>>>> have no intention to add a new feature to the non-DM driver.
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> But then this creates a massive disparity, it's like we're growing two
>>>>>>> USB stacks.
>>>>>>>
>>>>>>
>>>>>> Yep, unfortunately. But if we continue adding new features/fixes to
>>>>>> the old non-DM stuff, I am not sure how this can encourage people to
>>>>>> switch to DM.
>>>>>
>>>>>
>>>>>
>>>>> Correct. We definitely don't want to add new features to non-DM
>>>>> drivers / IF, if this is non-trivial.
>>>>>
>>>>>> Maybe I can check all boards that use xHCI to see if
>>>>>> they are switched to DM?
>>>>>
>>>>>
>>>>>
>>>>> xHCI is still quite new in U-Boot, so I would expect that all
>>>>> platforms using it, are using DM or at least not far away from using
>>>>> it. Yes, please check all xHCI "users", if they use DM. Then we
>>>>> know if and which users need some "persuasion" to switch over to
>>>>> DM soon. ;)
>>>>
>>>>
>>>> I checked all boards that have CONFIG_USB_XHCI_HCD defined but without
>>>> CONFIG_DM_USB. Here is the list.
>>>>
>>>> configs/uniphier_v8_defconfig:36:CONFIG_USB_XHCI_HCD=y
>>>> configs/xilinx_zynqmp_zc1751_xm015_dc1_defconfig:62:CONFIG_USB_XHCI_HCD=y
>>>> configs/am57xx_evm_nodt_defconfig:53:CONFIG_USB_XHCI_HCD=y
>>>> configs/evb-rk3328_defconfig:34:CONFIG_USB_XHCI_HCD=y
>>>> configs/ls1021atwr_nor_lpuart_defconfig:43:CONFIG_USB_XHCI_HCD=y
>>>> configs/uniphier_pxs2_ld6b_defconfig:44:CONFIG_USB_XHCI_HCD=y
>>>> configs/ls1012ardb_qspi_SECURE_BOOT_defconfig:43:CONFIG_USB_XHCI_HCD=y
>>>>
>>>> configs/ls1021atwr_sdcard_ifc_SECURE_BOOT_defconfig:57:CONFIG_USB_XHCI_HCD=y
>>>> configs/k2e_hs_evm_defconfig:34:CONFIG_USB_XHCI_HCD=y
>>>> configs/ls1021aqds_sdcard_qspi_defconfig:61:CONFIG_USB_XHCI_HCD=y
>>>> configs/am43xx_evm_ethboot_defconfig:48:CONFIG_USB_XHCI_HCD=y
>>>> configs/xilinx_zynqmp_ep_defconfig:70:CONFIG_USB_XHCI_HCD=y
>>>> configs/ls1021aqds_nand_defconfig:57:CONFIG_USB_XHCI_HCD=y
>>>> configs/ls1021atwr_qspi_defconfig:50:CONFIG_USB_XHCI_HCD=y
>>>> configs/k2g_evm_defconfig:45:CONFIG_USB_XHCI_HCD=y
>>>> configs/am57xx_evm_defconfig:63:CONFIG_USB_XHCI_HCD=y
>>>> configs/am43xx_hs_evm_defconfig:49:CONFIG_USB_XHCI_HCD=y
>>>> configs/am43xx_evm_defconfig:39:CONFIG_USB_XHCI_HCD=y
>>>> configs/ls1021atwr_nor_defconfig:42:CONFIG_USB_XHCI_HCD=y
>>>> configs/firefly-rk3399_defconfig:59:CONFIG_USB_XHCI_HCD=y
>>>> configs/puma-rk3399_defconfig:78:CONFIG_USB_XHCI_HCD=y
>>>> configs/cl-som-am57x_defconfig:55:CONFIG_USB_XHCI_HCD=y
>>>> configs/ls1021aqds_nor_SECURE_BOOT_defconfig:43:CONFIG_USB_XHCI_HCD=y
>>>> configs/uniphier_pro4_defconfig:43:CONFIG_USB_XHCI_HCD=y
>>>> configs/xilinx_zynqmp_zc1751_xm016_dc2_defconfig:61:CONFIG_USB_XHCI_HCD=y
>>>> configs/xilinx_zynqmp_zcu102_defconfig:63:CONFIG_USB_XHCI_HCD=y
>>>> configs/ls1021atwr_nor_SECURE_BOOT_defconfig:42:CONFIG_USB_XHCI_HCD=y
>>>> configs/cm_t43_defconfig:67:CONFIG_USB_XHCI_HCD=y
>>>> configs/k2g_hs_evm_defconfig:36:CONFIG_USB_XHCI_HCD=y
>>>> configs/am43xx_evm_qspiboot_defconfig:45:CONFIG_USB_XHCI_HCD=y
>>>> configs/ls1021aqds_qspi_defconfig:50:CONFIG_USB_XHCI_HCD=y
>>>> configs/am57xx_hs_evm_defconfig:67:CONFIG_USB_XHCI_HCD=y
>>>> configs/xilinx_zynqmp_zcu102_revB_defconfig:63:CONFIG_USB_XHCI_HCD=y
>>>> configs/ls1021aqds_sdcard_ifc_defconfig:55:CONFIG_USB_XHCI_HCD=y
>>>> configs/uniphier_ld20_defconfig:39:CONFIG_USB_XHCI_HCD=y
>>>> configs/am43xx_evm_usbhost_boot_defconfig:61:CONFIG_USB_XHCI_HCD=y
>>>> configs/ls1021atwr_sdcard_qspi_defconfig:61:CONFIG_USB_XHCI_HCD=y
>>>> configs/evb-rk3399_defconfig:60:CONFIG_USB_XHCI_HCD=y
>>>> configs/k2hk_evm_defconfig:43:CONFIG_USB_XHCI_HCD=y
>>>> configs/k2hk_hs_evm_defconfig:34:CONFIG_USB_XHCI_HCD=y
>>>> configs/k2e_evm_defconfig:43:CONFIG_USB_XHCI_HCD=y
>>>> configs/ls1021atwr_sdcard_ifc_defconfig:54:CONFIG_USB_XHCI_HCD=y
>>>> configs/k2l_evm_defconfig:43:CONFIG_USB_XHCI_HCD=y
>>>>
>>>> So it looks we have lots of conversion work to be done by many board
>>>> maintainers. I am not sure how to proceed on this.
>>>
>>>
>>> Marek reminded me, that he thinks that most of these platforms
>>> above will most likely select DM_USB implicitly via Kconfig.
>>>
>>> I did a quick check and it seems that at least these platforms
>>> have DM_USB enabled:
>>>
>>> ARCH_ZYNQ
>>> ARCH_ZYNQMP
>>> ARCH_UNIPHIER
>>> ARCH_ROCKCHIP
>>>
>>> and other from above very likely as well.
>>>
>>> Before you invest more time and effort into implementing the xHCI
>>> additions in a "non-DM cleaner way", I suggest to find out which
>>> targets really use xHCI without USB_DM. An easy check would be to
>>> add some #error to the non-DM part and run this commit through
>>> buildman / travis.
>>>
>>> What do you think?
>>
>> Ah, that's really a good idea. Thanks for the hints! I will launch a
>> buildman testing soon.
>>
> 
> Looks we have a smaller list indeed. Here is the buildman results:
> 
> ls1012ardb_qspi_SECURE_BOOT
> ls1021atwr_nor_SECURE_BOOT
> am43xx_hs_evm
> am57xx_hs_evm
> ls1021aqds_nand
> ls1021atwr_nor
> ls1021atwr_qspi
> cm_t43
> ls1021atwr_nor_lpuart
> ls1021aqds_sdcard_qspi
> k2hk_hs_evm
> am43xx_evm
> ls1021aqds_qspi
> am57xx_evm_nodt
> k2g_hs_evm
> ls1021atwr_sdcard_qspi
> am43xx_evm_ethboot
> ls1021aqds_sdcard_ifc
> k2l_evm
> am43xx_evm_usbhost_boot
> am43xx_evm_qspiboot
> k2g_evm
> am57xx_evm
> ls1021atwr_sdcard_ifc
> cl-som-am57x
> k2hk_evm
> k2e_evm
> ls1021atwr_sdcard_ifc_SECURE_BOOT
> ls1021aqds_nor_SECURE_BOOT
> k2e_hs_evm

Thanks. So this leaves only some platforms using xHCI without DM_USB
enabled indeed. I suspect that most of them don't have DM_USB enabled
just because of oversight. Let me write a short mail to the
maintainers, to see if they can enable DM_USB to make the way free
for a complete DM based xHCI support.

Thanks,
Stefan