[PATCH] PCI: designware-ep: use ffz() instead of find_first_zero_bit()

From: Niklas Cassel
Date: Thu Nov 16 2017 - 13:35:30 EST


find_first_zero_bit()'s parameter 'size' is defined in bits,
not in bytes.

find_first_zero_bit() was called with bytes rather than bits,
which thus defined a too low upper limit, causing
dw_pcie_ep_inbound_atu() to assign iatu index #4 to both bar 4
and bar 5, which made bar 5 overwrite the settings set by bar 4.

./pcitest.sh
BAR tests
BAR0: OKAY
BAR1: OKAY
BAR2: OKAY
BAR3: OKAY
BAR4: NOT OKAY
BAR5: OKAY

Fix this by using replacing find_first_zero_bit() with ffz(),
since ffz() only works on a single 'unsigned long' and therefore
does not need a size argument.

Signed-off-by: Niklas Cassel <niklas.cassel@xxxxxxxx>
---
drivers/pci/dwc/pcie-designware-ep.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/pci/dwc/pcie-designware-ep.c b/drivers/pci/dwc/pcie-designware-ep.c
index d53d5f168363..ab9a9e160daf 100644
--- a/drivers/pci/dwc/pcie-designware-ep.c
+++ b/drivers/pci/dwc/pcie-designware-ep.c
@@ -70,8 +70,7 @@ static int dw_pcie_ep_inbound_atu(struct dw_pcie_ep *ep, enum pci_barno bar,
u32 free_win;
struct dw_pcie *pci = to_dw_pcie_from_ep(ep);

- free_win = find_first_zero_bit(&ep->ib_window_map,
- sizeof(ep->ib_window_map));
+ free_win = ffz(ep->ib_window_map);
if (free_win >= ep->num_ib_windows) {
dev_err(pci->dev, "no free inbound window\n");
return -EINVAL;
@@ -96,8 +95,7 @@ static int dw_pcie_ep_outbound_atu(struct dw_pcie_ep *ep, phys_addr_t phys_addr,
u32 free_win;
struct dw_pcie *pci = to_dw_pcie_from_ep(ep);

- free_win = find_first_zero_bit(&ep->ob_window_map,
- sizeof(ep->ob_window_map));
+ free_win = ffz(ep->ob_window_map);
if (free_win >= ep->num_ob_windows) {
dev_err(pci->dev, "no free outbound window\n");
return -EINVAL;
--
2.14.2