On 10/12/2017 04:09 PM, David Laight wrote:
From: Pankaj Dubey
Sent: 12 October 2017 08:55
In pcie-designware.c many places we are calling "usleep_range" which
are in atomic context. This patch fixes these potential BUGs and
replaces "usleep_range" with mdelay calls.
Signed-off-by: Pankaj Dubey <pankaj.dubey@xxxxxxxxxxx>
---
drivers/pci/dwc/pcie-designware.c | 8 ++++----
drivers/pci/dwc/pcie-designware.h | 3 +--
2 files changed, 5 insertions(+), 6 deletions(-)
diff --git a/drivers/pci/dwc/pcie-designware.c b/drivers/pci/dwc/pcie-designware.c
index 88abddd..35d19b9 100644
--- a/drivers/pci/dwc/pcie-designware.c
+++ b/drivers/pci/dwc/pcie-designware.c
@@ -138,7 +138,7 @@ static void dw_pcie_prog_outbound_atu_unroll(struct dw_pcie *pci, int index,
if (val & PCIE_ATU_ENABLE)
return;
- usleep_range(LINK_WAIT_IATU_MIN, LINK_WAIT_IATU_MAX);
+ mdelay(LINK_WAIT_IATU_MIN);
}
Spinning for 9ms (possibly 10 times) isn't really a good idea.
Yes. It may not be a good idea, however in our experiment it never hit
maximum retry count.
I just converted usleep_range to mdelay keeping min time limitation as
it is, though I
am not sure, how do we arrived on these numbers in original code, may be
Joao Pinto
from Synopsys have some idea, I will try to do few experiment and try to
find out what
is sufficient minimum time in our hardware for these mdelay.
Thanks,
Pankaj Dubey
David
