On Thu, Jul 15, 2021 at 04:51:35PM +0200, Heinrich Schuchardt wrote: > On 7/8/21 10:22 AM, Michael Chang wrote: > > The u-boot efi console service registers a timer to poll the keyboard > > input in every 50ns. In the efi block io service, this timer is > > The event is triggered every 5000 ns not 50 ns. See > lib/efi_loader/efi_console.c:1309. The SetTimer() parameter is in > multiples of 100 ns. UEFI spec 2.9 has this sentence: > "TimerRelative: The event is to be signaled in TriggerTime 100ns units."
Indeed the value is mistakenly taken. Thanks to pointing this out and will correct that in followed version. > > evaluated on each block read, and since the timer interval is much less > > than the time needed to reading out a block (32kB) from the disk, the > > keyboard polling is therefore in the wake of each block read. > > > > Unfortunately USB keyboard spends too much time in polling. In my test > > usb_kbd_poll_for_event costs 40ms in usb_kbd_testc() to test if a > > I can't imagine that Linux is that slow. Why is U-Boot so slow? Please, > try to fix that code. Well I'm by no means a usb expert who is able to troubleshooting this myself so disabling the timer check is all I can do to mitigate the problem firstly. I certainly agree to investigate into usb_kbd_testc to understand what's happening under the hood, but please bear with me if that takes longer than expected to provide a solution/expaination along the way. For that I would have to seek for help internally from the company. > > character is in the queue. In combination with the number of blocks to > > be read from the disk, the extra amound of time delayed could be around > > 30 seconds to load linux and initrd. > > > > For that matters, the timer check is disabled in file loading to speed > > it up. The consequence would be losing the keystroke during the time > > file is loading, but that is acceptable IMHO. > > Disabling would mean that programs like iPXE cannot react to keyboard > input to interrupt a file transfer. Ok. fair enough. Thanks a lot for review. Regards, Michael > > Best regards > > Heinrich > > > > > Downstream bug reference: > > https://bugzilla.suse.com/show_bug.cgi?id=1171222 > > > > Signed-off-by: Michael Chang <mch...@suse.com> > > --- > > lib/efi_loader/efi_disk.c | 4 ++-- > > 1 file changed, 2 insertions(+), 2 deletions(-) > > > > diff --git a/lib/efi_loader/efi_disk.c b/lib/efi_loader/efi_disk.c > > index 307d5d759b..d090110b06 100644 > > --- a/lib/efi_loader/efi_disk.c > > +++ b/lib/efi_loader/efi_disk.c > > @@ -15,6 +15,7 @@ > > #include <log.h> > > #include <part.h> > > #include <malloc.h> > > +#include <watchdog.h> > > > > struct efi_system_partition efi_system_partition; > > > > @@ -103,8 +104,7 @@ static efi_status_t efi_disk_rw_blocks(struct > > efi_block_io *this, > > else > > n = blk_dwrite(desc, lba, blocks, buffer); > > > > - /* We don't do interrupts, so check for timers cooperatively */ > > - efi_timer_check(); > > + WATCHDOG_RESET(); > > > > EFI_PRINT("n=%lx blocks=%x\n", n, blocks); > > > > >
