Function pci_bridge_emul_init() may fail so correctly check for errors.

Link: https://lore.kernel.org/r/20200907111038.5811-3-pali@kernel.org
Fixes: 8a3ebd8d ("PCI: aardvark: Implement emulated root PCI bridge config space")
Signed-off-by: NPali Rohár <pali@kernel.org>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: NMarek Behún <marek.behun@nic.cz>

Include linux/gpio/consumer.h instead of linux/gpio.h, as is said in the
latter file.

This was reported by kernel test bot when compiling for s390.

  drivers/pci/controller/pci-aardvark.c:350:2: error: implicit declaration of function 'gpiod_set_value_cansleep' [-Werror,-Wimplicit-function-declaration]
  drivers/pci/controller/pci-aardvark.c:1074:21: error: implicit declaration of function 'devm_gpiod_get_from_of_node' [-Werror,-Wimplicit-function-declaration]
  drivers/pci/controller/pci-aardvark.c:1076:14: error: use of undeclared identifier 'GPIOD_OUT_LOW'

Link: https://lore.kernel.org/r/202006211118.LxtENQfl%25lkp@intel.com
Link: https://lore.kernel.org/r/20200907111038.5811-2-pali@kernel.org
Fixes: 5169a985 ("PCI: aardvark: Issue PERST via GPIO")
Reported-by: Nkernel test robot <lkp@intel.com>
Signed-off-by: NPali Rohár <pali@kernel.org>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: NMarek Behún <marek.behun@nic.cz>

The majority of DT based host drivers use the default .map_irq() and
.swizzle_irq() functions, so let's initialize the function pointers to
the default and drop setting them in the host drivers.

Drivers like iProc which don't support legacy interrupts need to set
.map_irq() back to NULL.

Link: https://lore.kernel.org/r/20200722022514.1283916-20-robh@kernel.orgSigned-off-by: NRob Herring <robh@kernel.org>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: NBjorn Helgaas <bhelgaas@google.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>

Now that pci_parse_request_of_pci_ranges() callers just setup
pci_host_bridge.windows and dma_ranges directly and don't need the bus
range returned, we can just initialize them when allocating the
pci_host_bridge struct.

With this, pci_parse_request_of_pci_ranges() becomes a static function.

Link: https://lore.kernel.org/r/20200722022514.1283916-19-robh@kernel.orgSigned-off-by: NRob Herring <robh@kernel.org>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: NBjorn Helgaas <bhelgaas@google.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>

Most host drivers only parse the DT bus range to set the root bus number
in pci_host_bridge.busnr. The ones that don't set busnr are buggy in
that they ignore what's in DT. Let's set busnr in pci_scan_root_bus_bridge()
where we already check for the bus resource and remove setting it in
host drivers.

Link: https://lore.kernel.org/r/20200722022514.1283916-12-robh@kernel.orgSigned-off-by: NRob Herring <robh@kernel.org>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: NBjorn Helgaas <bhelgaas@google.com>
Cc: Jingoo Han <jingoohan1@gmail.com>
Cc: Gustavo Pimentel <gustavo.pimentel@synopsys.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Cc: Will Deacon <will@kernel.org>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Jonathan Hunter <jonathanh@nvidia.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Ryder Lee <ryder.lee@mediatek.com>
Cc: Marek Vasut <marek.vasut+renesas@gmail.com>
Cc: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Cc: linux-tegra@vger.kernel.org
Cc: linux-mediatek@lists.infradead.org
Cc: linux-renesas-soc@vger.kernel.org

Use pci_is_root_bus() rather than tracking the root bus number to
determine if the bus is the root bus or not. This removes storing
duplicated data as well as the need for the host bridge driver to have
to care about the bus numbers in most cases.

Link: https://lore.kernel.org/r/20200722022514.1283916-5-robh@kernel.orgSigned-off-by: NRob Herring <robh@kernel.org>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: NBjorn Helgaas <bhelgaas@google.com>
Cc: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>

The struct pci_host_bridge is 0 initialized when allocated, so there's
no need to explicitly set fields to 0.

Link: https://lore.kernel.org/r/20200722022514.1283916-4-robh@kernel.orgSigned-off-by: NRob Herring <robh@kernel.org>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: NBjorn Helgaas <bhelgaas@google.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>

The host bridge's parent device is always the platform device. As we
already have a pointer to it in the devres functions, let's initialize
the parent device. Drivers can still override the parent if desired.

Link: https://lore.kernel.org/r/20200722022514.1283916-3-robh@kernel.orgSigned-off-by: NRob Herring <robh@kernel.org>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: NBjorn Helgaas <bhelgaas@google.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>

When there is no PCIe card connected and advk_pcie_rd_conf() or
advk_pcie_wr_conf() is called for PCI bus which doesn't belong to emulated
root bridge, the aardvark driver throws the following error message:

  advk-pcie d0070000.pcie: config read/write timed out

Obviously accessing PCIe registers of disconnected card is not possible.

Extend check in advk_pcie_valid_device() function for validating
availability of PCIe bus. If PCIe link is down, then the device is marked
as Not Found and the driver does not try to access these registers.

This is just an optimization to prevent accessing PCIe registers when card
is disconnected. Trying to access PCIe registers of disconnected card does
not cause any crash, kernel just needs to wait for a timeout. So if card
disappear immediately after checking for PCIe link (before accessing PCIe
registers), it does not cause any problems.

Link: https://lore.kernel.org/r/20200702083036.12230-1-pali@kernel.orgSigned-off-by: NPali Rohár <pali@kernel.org>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>

Use devm_platform_ioremap_resource() to simplify the code, since t
contains platform_get_resource() and devm_ioremap_resource() calls
respectively.

Link: https://lore.kernel.org/r/20200708155614.308-1-zhengdejin5@gmail.comSigned-off-by: NDejin Zheng <zhengdejin5@gmail.com>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: NRob Herring <robh@kernel.org>

Most callers of config read do not check for return value. But most of the
ones that do, checks for error indication in 'val' variable.

This patch updates error handling in advk_pcie_rd_conf() function. If PIO
transfer fails then 'val' variable is set to 0xffffffff which indicates
failture.

Link: https://lore.kernel.org/r/20200528162604.GA323482@bjorn-Precision-5520
Link: https://lore.kernel.org/r/20200601130315.18895-1-pali@kernel.orgReported-by: NBjorn Helgaas <helgaas@kernel.org>
Signed-off-by: NPali Rohár <pali@kernel.org>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>

PCI-E capability macros are already defined in linux/pci_regs.h.
Remove their reimplementation in pcie-aardvark.

Link: https://lore.kernel.org/r/20200430080625.26070-9-pali@kernel.orgTested-by: NTomasz Maciej Nowak <tmn505@gmail.com>
Signed-off-by: NPali Rohár <pali@kernel.org>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: NRob Herring <robh@kernel.org>
Acked-by: NThomas Petazzoni <thomas.petazzoni@bootlin.com>

With recent proposed changes for U-Boot it is possible that bootloader
won't initialize the PHY for this controller (currently the PHY is
initialized regardless whether PCI is used in U-Boot, but with these
proposed changes the PHY is initialized only on request).

Since the mvebu-a3700-comphy driver by Miquèl Raynal supports enabling
PCIe PHY, and since Linux' functionality should be independent on what
bootloader did, add code for enabling generic PHY if found in device OF
node.

The mvebu-a3700-comphy driver does PHY powering via SMC calls to ARM
Trusted Firmware. The corresponding code in ARM Trusted Firmware skips
one register write which U-Boot does not: step 7 ("Enable TX"), see [1].
Instead ARM Trusted Firmware expects PCIe driver to do this step,
probably because the register is in PCIe controller address space,
instead of PHY address space. We therefore add this step into the
advk_pcie_setup_hw function.

[1] https://git.trustedfirmware.org/TF-A/trusted-firmware-a.git/tree/drivers/marvell/comphy/phy-comphy-3700.c?h=v2.3-rc2#n836

Link: https://lore.kernel.org/r/20200430080625.26070-8-pali@kernel.orgTested-by: NTomasz Maciej Nowak <tmn505@gmail.com>
Signed-off-by: NMarek Behún <marek.behun@nic.cz>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: NRob Herring <robh@kernel.org>
Acked-by: NThomas Petazzoni <thomas.petazzoni@bootlin.com>
Cc: Miquèl Raynal <miquel.raynal@bootlin.com>

This register is applicable only when the controller is configured for
Endpoint mode, which is not the case for the current version of this
driver.

Attempting to remove this code though caused some ath10k cards to stop
working, so for some unknown reason it is needed here.

This should be investigated and a comment explaining this should be put
before the code, so we add a FIXME comment for now.

Link: https://lore.kernel.org/r/20200430080625.26070-7-pali@kernel.orgTested-by: NTomasz Maciej Nowak <tmn505@gmail.com>
Signed-off-by: NPali Rohár <pali@kernel.org>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: NRob Herring <robh@kernel.org>
Acked-by: NThomas Petazzoni <thomas.petazzoni@bootlin.com>

Add support for issuing PERST via GPIO specified in 'reset-gpios'
property (as described in PCI device tree bindings).

Some buggy cards (e.g. Compex WLE900VX or WLE1216) are not detected
after reboot when PERST is not issued during driver initialization.

If bootloader already enabled link training then issuing PERST has no
effect for some buggy cards (e.g. Compex WLE900VX) and these cards are
not detected. We therefore clear the LINK_TRAINING_EN register before.

It was observed that Compex WLE900VX card needs to be in PERST reset
for at least 10ms if bootloader enabled link training.

Tested on Turris MOX.

Link: https://lore.kernel.org/r/20200430080625.26070-6-pali@kernel.orgTested-by: NTomasz Maciej Nowak <tmn505@gmail.com>
Signed-off-by: NPali Rohár <pali@kernel.org>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: NThomas Petazzoni <thomas.petazzoni@bootlin.com>

Currently the aardvark driver trains link in PCIe gen2 mode. This may
cause some buggy gen1 cards (such as Compex WLE900VX) to be unstable or
even not detected. Moreover when ASPM code tries to retrain link second
time, these cards may stop responding and link goes down. If gen1 is
used this does not happen.

Unconditionally forcing gen1 is not a good solution since it may have
performance impact on gen2 cards.

To overcome this, read 'max-link-speed' property (as defined in PCI
device tree bindings) and use this as max gen mode. Then iteratively try
link training at this mode or lower until successful. After successful
link training choose final controller gen based on Negotiated Link Speed
from Link Status register, which should match card speed.

Link: https://lore.kernel.org/r/20200430080625.26070-5-pali@kernel.orgTested-by: NTomasz Maciej Nowak <tmn505@gmail.com>
Signed-off-by: NPali Rohár <pali@kernel.org>
Signed-off-by: NMarek Behún <marek.behun@nic.cz>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: NRob Herring <robh@kernel.org>
Acked-by: NThomas Petazzoni <thomas.petazzoni@bootlin.com>

Trying to change Link Status register does not have any effect as this
is a read-only register. Trying to overwrite bits for Negotiated Link
Width does not make sense.

In future proper change of link width can be done via Lane Count Select
bits in PCIe Control 0 register.

Trying to unconditionally enable ASPM L0s via ASPM Control bits in Link
Control register is wrong. There should be at least some detection if
endpoint supports L0s as isn't mandatory.

Moreover ASPM Control bits in Link Control register are controlled by
pcie/aspm.c code which sets it according to system ASPM settings,
immediately after aardvark driver probes. So setting these bits by
aardvark driver has no long running effect.

Remove code which touches ASPM L0s bits from this driver and let
kernel's ASPM implementation to set ASPM state properly.

Some users are reporting issues that this code is problematic for some
Intel wifi cards and removing it fixes them, see e.g.:
https://bugzilla.kernel.org/show_bug.cgi?id=196339

If problems with Intel wifi cards occur even after this commit, then
pcie/aspm.c code could be modified / hooked to not enable ASPM L0s state
for affected problematic cards.

Link: https://lore.kernel.org/r/20200430080625.26070-3-pali@kernel.orgTested-by: NTomasz Maciej Nowak <tmn505@gmail.com>
Signed-off-by: NPali Rohár <pali@kernel.org>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: NRob Herring <robh@kernel.org>
Acked-by: NThomas Petazzoni <thomas.petazzoni@bootlin.com>

Adding even 100ms (PCI_PM_D3COLD_WAIT) delay between enabling link
training and starting link training causes detection issues with some
buggy cards (such as Compex WLE900VX).

Move the code which enables link training immediately before the one
which starts link traning.

This fixes detection issues of Compex WLE900VX card on Turris MOX after
cold boot.

Link: https://lore.kernel.org/r/20200430080625.26070-2-pali@kernel.org
Fixes: f4c7d053 ("PCI: aardvark: Wait for endpoint to be ready...")
Tested-by: NTomasz Maciej Nowak <tmn505@gmail.com>
Signed-off-by: NPali Rohár <pali@kernel.org>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: NRob Herring <robh@kernel.org>
Acked-by: NThomas Petazzoni <thomas.petazzoni@bootlin.com>

The platform_get_irq*() interfaces return either a negative error number or
a valid IRQ.  0 is not a valid return value, so check for "< 0" to detect
failure as recommended by the function documentation.

On failure, return the error number from platform_get_irq*() instead of
making up a new one.

Link: https://lore.kernel.org/r/cover.1583952275.git.amanharitsh123@gmail.com
[bhelgaas: commit log, squash into one patch]
Signed-off-by: NAman Sharma <amanharitsh123@gmail.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Acked-by: NLinus Walleij <linus.walleij@linaro.org>
Cc: Richard Zhu <hongxing.zhu@nxp.com>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Karthikeyan Mitran <m.karthikeyan@mobiveil.co.in>
Cc: Hou Zhiqiang <Zhiqiang.Hou@nxp.com>
Cc: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Cc: Ryder Lee <ryder.lee@mediatek.com>
Cc: Marc Gonzalez <marc.w.gonzalez@free.fr>

Remove <linux/pci.h> and <linux/msi.h> from being included directly as part
of the include/linux/of_pci.h, and remove superfluous declaration of struct
of_phandle_args.

Move users of include <linux/of_pci.h> to include <linux/pci.h> and
<linux/msi.h> directly rather than rely on both being included transitively
through <linux/of_pci.h>.

Link: https://lore.kernel.org/r/20190903113059.2901-1-kw@linux.comSigned-off-by: NKrzysztof Wilczynski <kw@linux.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NRob Herring <robh@kernel.org>

Extend devm_of_pci_get_host_bridge_resources() and
pci_parse_request_of_pci_ranges() helpers to also parse the inbound
addresses from DT 'dma-ranges' and populate a resource list with the
translated addresses. This will help ensure 'dma-ranges' is always
parsed in a consistent way.
Tested-by: NSrinath Mannam <srinath.mannam@broadcom.com>
Tested-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com> # for AArdvark
Signed-off-by: NRob Herring <robh@kernel.org>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: NSrinath Mannam <srinath.mannam@broadcom.com>
Reviewed-by: NAndrew Murray <andrew.murray@arm.com>
Acked-by: NGustavo Pimentel <gustavo.pimentel@synopsys.com>
Cc: Jingoo Han <jingoohan1@gmail.com>
Cc: Gustavo Pimentel <gustavo.pimentel@synopsys.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Cc: Will Deacon <will@kernel.org>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Toan Le <toan@os.amperecomputing.com>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Tom Joseph <tjoseph@cadence.com>
Cc: Ray Jui <rjui@broadcom.com>
Cc: Scott Branden <sbranden@broadcom.com>
Cc: bcm-kernel-feedback-list@broadcom.com
Cc: Ryder Lee <ryder.lee@mediatek.com>
Cc: Karthikeyan Mitran <m.karthikeyan@mobiveil.co.in>
Cc: Hou Zhiqiang <Zhiqiang.Hou@nxp.com>
Cc: Simon Horman <horms@verge.net.au>
Cc: Shawn Lin <shawn.lin@rock-chips.com>
Cc: Heiko Stuebner <heiko@sntech.de>
Cc: Michal Simek <michal.simek@xilinx.com>
Cc: rfi@lists.rocketboards.org
Cc: linux-mediatek@lists.infradead.org
Cc: linux-renesas-soc@vger.kernel.org
Cc: linux-rockchip@lists.infradead.org

Convert aardvark to use the common pci_parse_request_of_pci_ranges().

There's no need to assign the resources to a temporary list first. Just
use bridge->windows directly and remove all the temporary list handling.
Tested-by: NThomas Petazzoni <thomas.petazzoni@bootlin.com>
Signed-off-by: NRob Herring <robh@kernel.org>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: NAndrew Murray <andrew.murray@arm.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>

Initialise every multiple-byte field of emulated PCI bridge config
space with proper cpu_to_le* macro. This is required since the structure
describing config space of emulated bridge assumes little-endian
convention.
Signed-off-by: NGrzegorz Jaszczyk <jaz@semihalf.com>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>

advk_pcie_wait_pio() can be called while holding a spinlock (from
pci_bus_read_config_dword()), then depends on jiffies in order to
timeout while polling on PIO state registers. In the case the PIO
transaction failed, the timeout will never happen and will also cause
the cpu to stall.

This decrements a variable and wait instead of using jiffies.
Signed-off-by: NRemi Pommarel <repk@triplefau.lt>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: NAndrew Murray <andrew.murray@arm.com>
Acked-by: NThomas Petazzoni <thomas.petazzoni@bootlin.com>

PCI_EXP_RTCTL is used to activate PME interrupt only, so writing into it
should not modify other interrupts' mask. The ISR mask polarity was also
inverted, when PCI_EXP_RTCTL_PMEIE is set PCIE_MSG_PM_PME_MASK mask bit
should actually be cleared.

Fixes: 8a3ebd8d ("PCI: aardvark: Implement emulated root PCI bridge config space")
Signed-off-by: NRemi Pommarel <repk@triplefau.lt>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: NThomas Petazzoni <thomas.petazzoni@bootlin.com>

When configuring pcie reset pin from gpio (e.g. initially set by
u-boot) to pcie function this pin goes low for a brief moment
asserting the PERST# signal. Thus connected device enters fundamental
reset process and link configuration can only begin after a minimal
100ms delay (see [1]).

Because the pin configuration comes from the "default" pinctrl it is
implicitly configured before the probe callback is called:

driver_probe_device()
  really_probe()
    ...
    pinctrl_bind_pins() /* Here pin goes from gpio to PCIE reset
                           function and PERST# is asserted */
    ...
    drv->probe()

[1] "PCI Express Base Specification", REV. 4.0
    PCI Express, February 19 2014, 6.6.1 Conventional Reset
Signed-off-by: NRemi Pommarel <repk@triplefau.lt>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: NThomas Petazzoni <thomas.petazzoni@bootlin.com>

Aardvark's PCI_EXP_LNKSTA_LT flag in its link status register is not
implemented and does not reflect the actual link training state (the
flag is always set to 0). In order to support link re-training feature
this flag has to be emulated. The Link Training and Status State
Machine (LTSSM) flag in Aardvark LMI config register could be used as
a link training indicator. Indeed if the LTSSM is in L0 or upper state
then link training has completed (see [1]).

Unfortunately because after asking a link retraining it takes a while
for the LTSSM state to become less than 0x10 (due to L0s to recovery
state transition delays), LTSSM can still be in L0 while link training
has not finished yet. So this waits for link to be in recovery or lesser
state before returning after asking for a link retrain.

[1] "PCI Express Base Specification", REV. 4.0
    PCI Express, February 19 2014, Table 4-14

Fixes: 8a3ebd8d ("PCI: aardvark: Implement emulated root PCI bridge config space")
Tested-by: NMarc Zyngier <maz@kernel.org>
Signed-off-by: NRemi Pommarel <repk@triplefau.lt>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: NAndrew Murray <andrew.murray@arm.com>
Acked-by: NThomas Petazzoni <thomas.petazzoni@bootlin.com>

Fix typos in drivers/pci.  Comment and whitespace changes only.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: NRandy Dunlap <rdunlap@infradead.org>

The call to of_get_next_child() returns a node pointer with refcount
incremented thus it must be explicitly decremented after the last
usage.

irq_domain_add_linear() also calls of_node_get() to increase refcount,
so irq_domain will not be affected when it is released.

Detected by coccinelle with the following warnings:
  ./drivers/pci/controller/pci-aardvark.c:826:1-7: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 798, but without a corresponding object release within this function.
Signed-off-by: NWen Yang <wen.yang99@zte.com.cn>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: linux-pci@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org

Fix the following sparse warning:

drivers/pci/controller/pci-aardvark.c:469:28: warning:
 symbol 'advk_pci_bridge_emul_ops' was not declared. Should it be static?

Fixes: 8a3ebd8d ("PCI: aardvark: Implement emulated root PCI bridge config space")
Signed-off-by: NWei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: NThomas Petazzoni <thomas.petazzoni@bootlin.com>

Depending on the capabilities of the PCI controller/platform, the
PCI-to-PCI bridge emulation behavior might need to be different. For
example, on platforms that use the pci-mvebu code, we currently don't
support prefetchable memory BARs, so the corresponding fields in the
PCI-to-PCI bridge configuration space should be read-only.

To implement this, extend pci_bridge_emul_init() to take a "flags"
argument, with currently one flag supported:

PCI_BRIDGE_EMUL_NO_PREFETCHABLE_BAR

that will make the prefetchable memory base and limit registers
read-only.

The pci-mvebu and pci-aardvark drivers are updated accordingly.

Fixes: 1f08673e ("PCI: mvebu: Convert to PCI emulated bridge config space")
Reported-by: NLuís Mendes <luis.p.mendes@gmail.com>
Reported-by: NLeigh Brown <leigh@solinno.co.uk>
Tested-by: NLeigh Brown <leigh@solinno.co.uk>
Tested-by: NLuis Mendes <luis.p.mendes@gmail.com>
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@bootlin.com>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: stable@vger.kernel.org
Cc: Luís Mendes <luis.p.mendes@gmail.com>
Cc: Leigh Brown <leigh@solinno.co.uk>

The PCI controller in the Marvell Armada 3720 does not implement a
software-accessible root port PCI bridge configuration space. This
causes a number of problems when using PCIe switches or when the Max
Payload size needs to be aligned between the root complex and the
endpoint.

Implementing an emulated root PCI bridge, like is already done in the
pci-mvebu driver for older Marvell platforms allows to solve those
issues, and also to support features such as ASR, PME, VC, HP.
Signed-off-by: NZachary Zhang <zhangzg@marvell.com>
[Thomas: convert to the common emulated PCI bridge logic.]
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@bootlin.com>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>

When testing the R-Car PCIe driver on the Condor board, if the PCIe PHY
driver was left disabled, the kernel crashed with this BUG:

  kernel BUG at lib/ioremap.c:72!
  Internal error: Oops - BUG: 0 [#1] PREEMPT SMP
  Modules linked in:
  CPU: 0 PID: 39 Comm: kworker/0:1 Not tainted 4.17.0-dirty #1092
  Hardware name: Renesas Condor board based on r8a77980 (DT)
  Workqueue: events deferred_probe_work_func
  pstate: 80000005 (Nzcv daif -PAN -UAO)
  pc : ioremap_page_range+0x370/0x3c8
  lr : ioremap_page_range+0x40/0x3c8
  sp : ffff000008da39e0
  x29: ffff000008da39e0 x28: 00e8000000000f07
  x27: ffff7dfffee00000 x26: 0140000000000000
  x25: ffff7dfffef00000 x24: 00000000000fe100
  x23: ffff80007b906000 x22: ffff000008ab8000
  x21: ffff000008bb1d58 x20: ffff7dfffef00000
  x19: ffff800009c30fb8 x18: 0000000000000001
  x17: 00000000000152d0 x16: 00000000014012d0
  x15: 0000000000000000 x14: 0720072007200720
  x13: 0720072007200720 x12: 0720072007200720
  x11: 0720072007300730 x10: 00000000000000ae
  x9 : 0000000000000000 x8 : ffff7dffff000000
  x7 : 0000000000000000 x6 : 0000000000000100
  x5 : 0000000000000000 x4 : 000000007b906000
  x3 : ffff80007c61a880 x2 : ffff7dfffeefffff
  x1 : 0000000040000000 x0 : 00e80000fe100f07
  Process kworker/0:1 (pid: 39, stack limit = 0x        (ptrval))
  Call trace:
   ioremap_page_range+0x370/0x3c8
   pci_remap_iospace+0x7c/0xac
   pci_parse_request_of_pci_ranges+0x13c/0x190
   rcar_pcie_probe+0x4c/0xb04
   platform_drv_probe+0x50/0xbc
   driver_probe_device+0x21c/0x308
   __device_attach_driver+0x98/0xc8
   bus_for_each_drv+0x54/0x94
   __device_attach+0xc4/0x12c
   device_initial_probe+0x10/0x18
   bus_probe_device+0x90/0x98
   deferred_probe_work_func+0xb0/0x150
   process_one_work+0x12c/0x29c
   worker_thread+0x200/0x3fc
   kthread+0x108/0x134
   ret_from_fork+0x10/0x18
  Code: f9004ba2 54000080 aa0003fb 17ffff48 (d4210000)

It turned out that pci_remap_iospace() wasn't undone when the driver's
probe failed, and since devm_phy_optional_get() returned -EPROBE_DEFER,
the probe was retried, finally causing the BUG due to trying to remap
already remapped pages.

The Aardvark PCI controller driver has the same issue.
Replace pci_remap_iospace() with its devm_ managed version to fix the bug.

Fixes: 8c39d710 ("PCI: aardvark: Add Aardvark PCI host controller driver")
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
[lorenzo.pieralisi@arm.com: updated the commit log]
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NThomas Petazzoni <thomas.petazzoni@bootlin.com>
Reviewed-by: NLinus Walleij <linus.walleij@linaro.org>

Part of advk_pcie_probe() is exactly an open-coded version of
pci_host_probe(). So instead of duplicating this code, use
pci_host_probe() directly.
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@bootlin.com>
[lorenzo.pieralisi@arm.com: updated commit log]
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>

The PCIE I/O and MEM resource allocation mechanism is that root bus
goes through the following steps:

1. Check PCI bridges' range and computes I/O and Mem base/limits.

2. Sort all subordinate devices I/O and MEM resource requirements and
   allocate the resources and writes/updates subordinate devices'
   requirements to PCI bridges I/O and Mem MEM/limits registers.

Currently, PCI Aardvark driver only handles the second step and lacks
the first step, so there is an I/O and MEM resource allocation failure
when using a PCI switch. This commit fixes that by sizing bridges
before doing the resource allocation.

Fixes: 8c39d710 ("PCI: aardvark: Add Aardvark PCI host controller
driver")
Signed-off-by: NZachary Zhang <zhangzg@marvell.com>
[Thomas: edit commit log.]
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@bootlin.com>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: <stable@vger.kernel.org>

Outbound window is used to translate CPU space addresses to PCIe space
addresses when the CPU initiates PCIe transactions.

According to the suggestion of the HW designers, the recommended
solution is to use the default outbound parameters, even though the
current outbound window setting does not cause any known functional
issue.

This patch doesn't address any known functional issue, but aligns to
HW design guidelines, and removes code that isn't needed.
Signed-off-by: NEvan Wang <xswang@marvell.com>
[Thomas: tweak commit log.]
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@bootlin.com>
[lorenzo.pieralisi@arm.com: handled host->controller dir move]
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: NVictor Gu <xigu@marvell.com>
Reviewed-by: NNadav Haklai <nadavh@marvell.com>

In other to mimic other PCIe host controller drivers, introduce an
advk_pcie_valid_device() helper, used in the configuration read/write
functions.
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@bootlin.com>
[lorenzo.pieralisi@arm.com: updated host->controller dir move]
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>

Native PCI drivers for root complex devices were originally all in
drivers/pci/host/.  Some of these devices can also be operated in endpoint
mode.  Drivers for endpoint mode didn't seem to fit in the "host"
directory, so we put both the root complex and endpoint drivers in
per-device directories, e.g., drivers/pci/dwc/, drivers/pci/cadence/, etc.

These per-device directories contain trivial Kconfig and Makefiles and
clutter drivers/pci/.  Make a new drivers/pci/controllers/ directory and
collect all the device-specific drivers there.

No functional change intended.

Link: https://lkml.kernel.org/r/1520304202-232891-1-git-send-email-shawn.lin@rock-chips.comSigned-off-by: NShawn Lin <shawn.lin@rock-chips.com>
[bhelgaas: changelog]
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

of_pci_get_host_bridge_resources() allocates the resource structures it
fills dynamically, but none of its callers care to release them so far.
Rather than requiring everyone to do this explicitly, convert the existing
function to a managed version.
Tested-by: NVladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NVladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
Acked-by: NJoao Pinto <jpinto@synopsys.com>
Acked-by: NJingoo Han <jingoohan1@gmail.com>
CC: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>

Another step towards a managed version of
of_pci_get_host_bridge_resources(): Feed in the underlying device, rather
than just the OF node.  This will allow us to use managed resource
allocation internally later on.
Tested-by: NVladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NVladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
Acked-by: NJingoo Han <jingoohan1@gmail.com>
CC: Joao Pinto <Joao.Pinto@synopsys.com>
CC: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>