target/linux/mvebu/patches-4.14/522-PCI-aardvark-fix-logic-in-PCI-configuration-read-write-functions.patch

   1 From patchwork Thu Sep 28 12:58:32 2017
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   5 Subject: [v2, 1/7] PCI: aardvark: fix logic in PCI configuration read/write
   6  functions
   7 X-Patchwork-Submitter: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
   8 X-Patchwork-Id: 819586
   9 Message-Id: <20170928125838.11887-2-thomas.petazzoni@free-electrons.com>
  10 To: Bjorn Helgaas <bhelgaas@google.com>, linux-pci@vger.kernel.org
  11 Cc: Jason Cooper <jason@lakedaemon.net>, Andrew Lunn <andrew@lunn.ch>,
  12  Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>, Gregory Clement
  13  <gregory.clement@free-electrons.com>,
  14  Nadav Haklai <nadavh@marvell.com>, Hanna Hawa <hannah@marvell.com>,
  15  Yehuda Yitschak <yehuday@marvell.com>,
  16  linux-arm-kernel@lists.infradead.org, Antoine Tenart
  17  <antoine.tenart@free-electrons.com>, =?utf-8?q?Miqu=C3=A8l_Raynal?=
  18  <miquel.raynal@free-electrons.com>, Victor Gu <xigu@marvell.com>,
  19  stable@vger.kernel.org, Thomas Petazzoni
  20  <thomas.petazzoni@free-electrons.com>
  21 Date: Thu, 28 Sep 2017 14:58:32 +0200
  22 From: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
  23 List-Id: <linux-pci.vger.kernel.org>
  24
  25 From: Victor Gu <xigu@marvell.com>
  26
  27 The PCI configuration space read/write functions were special casing
  28 the situation where PCI_SLOT(devfn) != 0, and returned
  29 PCIBIOS_DEVICE_NOT_FOUND in this case.
  30
  31 However, will this is what is intended for the root bus, it is not
  32 intended for the child busses, as it prevents discovering devices with
  33 PCI_SLOT(x) != 0. Therefore, we return PCIBIOS_DEVICE_NOT_FOUND only
  34 if we're on the root bus.
  35
  36 Fixes: 8c39d710363c1 ("PCI: aardvark: Add Aardvark PCI host controller driver")
  37 Cc: <stable@vger.kernel.org>
  38 Signed-off-by: Victor Gu <xigu@marvell.com>
  39 Reviewed-by: Wilson Ding <dingwei@marvell.com>
  40 Reviewed-by: Nadav Haklai <nadavh@marvell.com>
  41 [Thomas: tweak commit log.]
  42 Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
  43 ---
  44  drivers/pci/host/pci-aardvark.c | 4 ++--
  45  1 file changed, 2 insertions(+), 2 deletions(-)
  46
  47 --- a/drivers/pci/host/pci-aardvark.c
  48 +++ b/drivers/pci/host/pci-aardvark.c
  49 @@ -440,7 +440,7 @@ static int advk_pcie_rd_conf(struct pci_
  50         u32 reg;
  51         int ret;
  52
  53 -       if (PCI_SLOT(devfn) != 0) {
  54 +       if ((bus->number == pcie->root_bus_nr) && (PCI_SLOT(devfn) != 0)) {
  55                 *val = 0xffffffff;
  56                 return PCIBIOS_DEVICE_NOT_FOUND;
  57         }
  58 @@ -494,7 +494,7 @@ static int advk_pcie_wr_conf(struct pci_
  59         int offset;
  60         int ret;
  61
  62 -       if (PCI_SLOT(devfn) != 0)
  63 +       if ((bus->number == pcie->root_bus_nr) && (PCI_SLOT(devfn) != 0))
  64                 return PCIBIOS_DEVICE_NOT_FOUND;
  65
  66         if (where % size)