From: Greg Kroah-Hartman gregkh@linuxfoundation.org
[ 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 mathias.nyman@linux.intel.com Reported-by: Peter Zijlstra peterz@infradead.org Cc: Jann Horn jannh@google.com Cc: Chunfeng Yun chunfeng.yun@mediatek.com Fixes: 796eed4b2342 ("usb: early: convert to readl_poll_timeout_atomic()") Link: https://lore.kernel.org/r/c2b5c9bb-1b75-bf56-3754-b5b18812d65e@linux.intel.c... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- 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 be4ecbabdd586..6c0434100e38c 100644 --- a/drivers/usb/early/xhci-dbc.c +++ b/drivers/usb/early/xhci-dbc.c @@ -14,7 +14,6 @@ #include <linux/pci_ids.h> #include <linux/memblock.h> #include <linux/io.h> -#include <linux/iopoll.h> #include <asm/pci-direct.h> #include <asm/fixmap.h> #include <linux/bcd.h> @@ -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)