Dear Steve Heckman, > Marek, > > I've been working with Jim on this. > > The latest u-boot code we tried (2012.07) does seem to be much faster > WRT reading ext volumes from USB media. We were still able to eke > out a bit more speed by removing the Test Unit Ready calls per Read/Write. > In my experience, you only call Test Unit Ready during initialization of > a device (e.g., SCSI) or after device reset. > > We still haven't heard a reason why it is being done for each Read and > Write > operation. Was it put in to work around bad hardware?
I have zero idea, it was there ever since ... let's apply similar patch and see how it fares. > Thanks, > Steve Heckman > > On Sun, Aug 12, 2012 at 7:54 PM, Marek Vasut <ma...@denx.de> wrote: > > Dear Jim Shimer, > > > > > While tuning ext2load, we found that usb_test_unit_ready was being > > > called every block read. We compared the usb block storage to the > > > scsi block storage cmd_scsi.c, and found that the scsi device was only > > > calling its scsi_setup_test_unit_ready() during scsi_can. It appears > > > that usb_test_unit_ready() really only needs to be called once during > > > usb_stor_scan(), via usb_stor_get_info(). Is there a particular > > > reason usb_test_unit_ready is called for every block read, or do you > > > think its > > > > ok > > > > > to only call during usb_stor_scan()? We're finding this speeds up > > > > ext2load > > > > > quite a bit. > > > > Jim, did we get anywhere on this one ? Can you try with the new ext4 code > > in > > Wolfgangs' u-boot-master/ext4 branch? > > > > > Regards, > > > Jim > > > > Best regards, > > Marek Vasut Best regards, Marek Vasut _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
