From 9f8b3f238530b168d4e9a5024a5d21fc966248dd Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Fri, 17 Dec 2021 16:24:30 +0100 Subject: [PATCH] Revert "usb: early: convert to readl_poll_timeout_atomic()" [ Upstream commit c4d936efa46d8ea183df16c0f3fa4423327da51d ] This reverts commit 796eed4b2342c9d6b26c958e92af91253a2390e1. This change causes boot lockups when using "arlyprintk=xdbc" because ktime can not be used at this point in time in the boot process. Also, it is not needed for very small delays like this. Reported-by: Mathias Nyman Reported-by: Peter Zijlstra Cc: Jann Horn Cc: Chunfeng Yun Fixes: 796eed4b2342 ("usb: early: convert to readl_poll_timeout_atomic()") Link: https://lore.kernel.org/r/c2b5c9bb-1b75-bf56-3754-b5b18812d65e@linux.intel.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- drivers/usb/early/xhci-dbc.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-) diff --git a/drivers/usb/early/xhci-dbc.c b/drivers/usb/early/xhci-dbc.c index be4ecba..6c04341 100644 --- a/drivers/usb/early/xhci-dbc.c +++ b/drivers/usb/early/xhci-dbc.c @@ -14,7 +14,6 @@ #include #include #include -#include #include #include #include @@ -136,9 +135,17 @@ static int handshake(void __iomem *ptr, u32 mask, u32 done, int wait, int delay) { u32 result; - return readl_poll_timeout_atomic(ptr, result, - ((result & mask) == done), - delay, wait); + /* Can not use readl_poll_timeout_atomic() for early boot things */ + do { + result = readl(ptr); + result &= mask; + if (result == done) + return 0; + udelay(delay); + wait -= delay; + } while (wait > 0); + + return -ETIMEDOUT; } static void __init xdbc_bios_handoff(void) -- 2.7.4