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| author | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-12-17 18:24:30 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-12-17 18:29:11 +0300 |
| commit | c4d936efa46d8ea183df16c0f3fa4423327da51d (patch) | |
| tree | 9ed73e7ac7d9293abc642d4a9e940a733af91d47 /drivers/usb/early/xhci-dbc.c | |
| parent | a0b24a566258acada7a819cc2ddf67c75f9dce08 (diff) | |
| download | linux-c4d936efa46d8ea183df16c0f3fa4423327da51d.tar.xz | |
Revert "usb: early: convert to readl_poll_timeout_atomic()"
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.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/usb/early/xhci-dbc.c')
| -rw-r--r-- | drivers/usb/early/xhci-dbc.c | 15 |
1 files changed, 11 insertions, 4 deletions
diff --git a/drivers/usb/early/xhci-dbc.c b/drivers/usb/early/xhci-dbc.c index 933d77ad0a64..4502108069cd 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) |