[U-Boot] [PATCH v2] usb: fix usb_stor_read/write on DM

[Masahiro Yamada]

2017-07-14 19:07 GMT+09:00 Marek Vasut <marex at denx.de>:
> On 07/14/2017 04:31 AM, Masahiro Yamada wrote:
>> Prior to DM, we could not enable different types of USB controllers
>> at the same time.  DM was supposed to loosen the limitation.  It is
>> true that we can compile drivers, but they do not work.
>>
>> For example, if EHCI is enabled, xHCI fails as follows:
>>
>>   => usb read 82000000 0 2000
>>
>>   USB read: device 0 block # 0, count 8192 ... WARN halted endpoint, queueing URB anyway.
>>   Unexpected XHCI event TRB, skipping... (3fb54010 00000001 13000000 01008401)
>>   BUG: failure at drivers/usb/host/xhci-ring.c:489/abort_td()!
>>   BUG!
>>   ### ERROR ### Please RESET the board ###
>>
>> The cause of the error seems the following code:
>>
>>   #ifdef CONFIG_USB_EHCI_HCD
>>   /*
>>    * The U-Boot EHCI driver can handle any transfer length as long as there is
>>    * enough free heap space left, but the SCSI READ(10) and WRITE(10) commands are
>>    * limited to 65535 blocks.
>>    */
>>   #define USB_MAX_XFER_BLK    65535
>>   #else
>>   #define USB_MAX_XFER_BLK    20
>>   #endif
>>
>> To fix the problem, choose the chunk size at run-time for CONFIG_BLK.
>
> What happens if CONFIG_BLK is not set ?

USB_MAX_XFER_BLK is chosen.



> Why is it 20 for XHCI anyway ?

You are the maintainer.
(I hope) you have better knowledge with this.

Looks like the following commit was picked up by you.



commit cffcc503580907d733e694d505e12ff6ec6c679a
Author:     Benoît Thébaudeau <benoit.thebaudeau at advansee.com>
AuthorDate: Fri Aug 10 18:26:50 2012 +0200
Commit:     Marek Vasut <marex at denx.de>
CommitDate: Sat Sep 1 16:21:52 2012 +0200

    usb_storage: Restore non-EHCI support

    The commit 5dd95cf made the MSC driver EHCI-specific. This patch restores a
    basic support of non-EHCI HCDs, like before that commit.

    The fallback transfer size is certainly not optimal, but at least
it should work
    like before.

    Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau at advansee.com>
    Cc: Marek Vasut <marex at denx.de>
    Cc: Ilya Yanok <ilya.yanok at cogentembedded.com>
    Cc: Stefan Herbrechtsmeier <stefan at herbrechtsmeier.net>

diff --git a/common/usb_storage.c b/common/usb_storage.c
index bdc306f587fd..0cd6399a3c42 100644
--- a/common/usb_storage.c
+++ b/common/usb_storage.c
@@ -155,11 +155,15 @@ struct us_data {
        trans_cmnd      transport;              /* transport routine */
 };

+#ifdef CONFIG_USB_EHCI
 /*
  * The U-Boot EHCI driver cannot handle more than 5 page aligned buffers
  * of 4096 bytes in a transfer without running itself out of qt_buffers
  */
 #define USB_MAX_XFER_BLK(start, blksz) (((4096 * 5) - (start % 4096)) / blksz)
+#else
+#define USB_MAX_XFER_BLK(start, blksz) 20
+#endif

 static struct us_data usb_stor[USB_MAX_STOR_DEV];







-- 
Best Regards
Masahiro Yamada