Both i.MX7D and i.MX8MQ have the same behaviour when it comes to
clearing DIRECT_SPEED_CHANGE bit when no speed change occurs, so to
handle variants correctly add a flag instead of checking the IP block
variant.
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
[lorenzo.pieralisi@arm.com: updated log]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Fabio Estevam <fabio.estevam@nxp.com>
Cc: Chris Healy <cphealy@gmail.com>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Leonard Crestez <leonard.crestez@nxp.com>
Cc: "A.s. Dong" <aisheng.dong@nxp.com>
Cc: Richard Zhu <hongxing.zhu@nxp.com>
PCIe PHY IP block on i.MX7D differs from the one used on i.MX6 family,
so none of the code in the current implementation of
imx6_setup_phy_mpll() or imx6_pcie_reset_phy() is applicable.
Introduce IMX6_PCIE_FLAG_IMX6_PHY and check for it in the aforementioned
functions to make sure they are only executed on appropriate PCIe IP
variants.
Tested-by: Trent Piepho <tpiepho@impinj.com>
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
[lorenzo.pieralisi@arm.com: updated log]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Fabio Estevam <fabio.estevam@nxp.com>
Cc: Chris Healy <cphealy@gmail.com>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Leonard Crestez <leonard.crestez@nxp.com>
Cc: "A.s. Dong" <aisheng.dong@nxp.com>
Cc: Richard Zhu <hongxing.zhu@nxp.com>
Introduce driver data struct. This will simplify handling of device
specific differences.
Signed-off-by: Stefan Agner <stefan@agner.ch>
[andrew.smirnov@gmail.com reformatted drvdata, to simplify future diffs]
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Fabio Estevam <fabio.estevam@nxp.com>
Cc: Chris Healy <cphealy@gmail.com>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Leonard Crestez <leonard.crestez@nxp.com>
Cc: "A.s. Dong" <aisheng.dong@nxp.com>
Cc: Richard Zhu <hongxing.zhu@nxp.com>
Replace bit rotation operation (1 << bit) with BIT(bit), which
simplifies code reading.
No functional change is intended.
Signed-off-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Joao Pinto <jpinto@synopsys.com>
Cc: Jingoo Han <jingoohan1@gmail.com>
Improve code readability and simplifies mask/unmask operations by
inverting the applied logic (no functional change is intended).
Replace variable name from irq_status to irq_mask, since its goal is to
keep track of which interrupts are masked or not.
Signed-off-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Joao Pinto <jpinto@synopsys.com>
Cc: Jingoo Han <jingoohan1@gmail.com>
Rename variable from data to d to maintain consistency between driver
functions.
No functional change is intended.
Signed-off-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Joao Pinto <jpinto@synopsys.com>
Cc: Jingoo Han <jingoohan1@gmail.com>
Rename variable from data to d to maintain consistency between driver
functions.
No functional change is intended.
Signed-off-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Joao Pinto <jpinto@synopsys.com>
Cc: Jingoo Han <jingoohan1@gmail.com>
Rename variable from data to d to maintain consistency between driver
functions, such as dw_pci_setup_msi_msg().
No functional change is intended.
Signed-off-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Joao Pinto <jpinto@synopsys.com>
Cc: Jingoo Han <jingoohan1@gmail.com>
Rename variable from data to d to maintain consistency between driver
functions, such as dw_msi_mask_irq() and dw_msi_unmask_irq().
No functional change is intended.
Signed-off-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Joao Pinto <jpinto@synopsys.com>
Cc: Jingoo Han <jingoohan1@gmail.com>
Remove unnecessary header include (signal.h) since it doesn't provide
any needed symbols.
Signed-off-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Joao Pinto <jpinto@synopsys.com>
Cc: Jingoo Han <jingoohan1@gmail.com>
Remove unnecessary header include (of_gpio.h) since it doesn't provide
any needed symbols.
Signed-off-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Joao Pinto <jpinto@synopsys.com>
Cc: Jingoo Han <jingoohan1@gmail.com>
Revert commit 3d71746c42 ("PCI: armada8k: Add support for gpio controlled
reset signal").
That commit breaks boot on Macchiatobin board when a Mellanox NIC is
present in the PCIe slot.
It turns out that full reset cycle requires first comphy serdes
initialization. Reset signal toggle without comphy initialization makes
access to PCI configuration registers stall indefinitely. U-Boot toggles
the Macchiatobin PCIe reset line already at boot, after initializing the
comphy serdes.
So while commit 3d71746c42 ("PCI: armada8k: Add support for gpio controlled
reset signal") enables PCIe on platforms that U-Boot does not touch the
reset line (like Clearfog GT-8K), it breaks PCIe (and boot) on the
Macchiatobin board.
Revert commit 3d71746c42 ("PCI: armada8k: Add support for gpio controlled
reset signal") entirely to fix the Macchiatobin regression.
Reported-by: Sven Auhagen <sven.auhagen@voleatech.de>
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
The check on the device_link_add() return value is wrong;
this leads to erroneous code execution, so fix it.
Fixes: 3f7cceeab8 ("PCI: imx: Add multi-pd support")
Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>
[lorenzo.pieralisi@arm.com: updated commit log]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
On chips without a separate power domain for PCI (such as 6q/6qp) the
imx6_pcie_attach_pd() function incorrectly returns an error.
Fix by returning 0 if dev_pm_domain_attach_by_name() does not find
anything.
Fixes: 3f7cceeab8 ("PCI: imx: Add multi-pd support")
Reported-by: Lukas F.Hartmann <lukas@mntmn.com>
Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>
[lorenzo.pieralisi@arm.com: updated commit log]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Certain PHYs used with PCIe controller can also be used with other
controllers such as USB or SATA. In order to configure the PHY
to work with PCIe controller, invoke phy_set_mode() API with mode
set to PHY_MODE_PCIE.
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
[lorenzo.pieralisi@arm.com: updated commit log]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
dra74x/dra76x and dra72x have separate compatible strings. Add support
for these compatible strings in pci-dra7xx driver to perform syscon
configurations required to get x2 mode working.
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
In order to provide the most performance and/or compatible settings,
ensure VMD root buses observe the pcie bus tuning settings by
configuring those settings prior to adding the devices to the pcie tree.
This patch open-codes pci_rescan_bus() and configures the buses prior to
adding devices and attaching drivers.
Signed-off-by: Jon Derrick <jonathan.derrick@intel.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Keith Busch <keith.busch@intel.com>
We've always had a weird situation around dma_zalloc_coherent. To
safely support mapping the allocations to userspace major architectures
like x86 and arm have always zeroed allocations from dma_alloc_coherent,
but a couple other architectures were missing that zeroing either always
or in corner cases. Then later we grew anothe dma_zalloc_coherent
interface to explicitly request zeroing, but that just added __GFP_ZERO
to the allocation flags, which for some allocators that didn't end
up using the page allocator ended up being a no-op and still not
zeroing the allocations.
So for this merge window I fixed up all remaining architectures to zero
the memory in dma_alloc_coherent, and made dma_zalloc_coherent a no-op
wrapper around dma_alloc_coherent, which fixes all of the above issues.
dma_zalloc_coherent is now pointless and can go away, and Luis helped
me writing a cocchinelle script and patch series to kill it, which I
think we should apply now just after -rc1 to finally settle these
issue.
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Merge tag 'remove-dma_zalloc_coherent-5.0' of git://git.infradead.org/users/hch/dma-mapping
Pull dma_zalloc_coherent() removal from Christoph Hellwig:
"We've always had a weird situation around dma_zalloc_coherent. To
safely support mapping the allocations to userspace major
architectures like x86 and arm have always zeroed allocations from
dma_alloc_coherent, but a couple other architectures were missing that
zeroing either always or in corner cases.
Then later we grew anothe dma_zalloc_coherent interface to explicitly
request zeroing, but that just added __GFP_ZERO to the allocation
flags, which for some allocators that didn't end up using the page
allocator ended up being a no-op and still not zeroing the
allocations.
So for this merge window I fixed up all remaining architectures to
zero the memory in dma_alloc_coherent, and made dma_zalloc_coherent a
no-op wrapper around dma_alloc_coherent, which fixes all of the above
issues.
dma_zalloc_coherent is now pointless and can go away, and Luis helped
me writing a cocchinelle script and patch series to kill it, which I
think we should apply now just after -rc1 to finally settle these
issue"
* tag 'remove-dma_zalloc_coherent-5.0' of git://git.infradead.org/users/hch/dma-mapping:
dma-mapping: remove dma_zalloc_coherent()
cross-tree: phase out dma_zalloc_coherent() on headers
cross-tree: phase out dma_zalloc_coherent()
Building the driver when GPIOLIB=n is not selected is causing the following
compilation failure:
drivers/pci/controller/dwc/pci-meson.c: In function 'meson_pcie_assert_reset':
drivers/pci/controller/dwc/pci-meson.c:290:2: error: implicit declaration of function 'gpiod_set_value_cansleep'; did you mean 'gpio_set_value_cansleep'? [-Werror=implicit-function-declaration]
gpiod_set_value_cansleep(mp->reset_gpio, 0);
^~~~~~~~~~~~~~~~~~~~~~~~
gpio_set_value_cansleep
drivers/pci/controller/dwc/pci-meson.c: In function 'meson_pcie_probe':
drivers/pci/controller/dwc/pci-meson.c:540:19: error: implicit declaration of function 'devm_gpiod_get'; did you mean 'devm_gpio_free'? [-Werror=implicit-function-declaration]
mp->reset_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_LOW);
^~~~~~~~~~~~~~
devm_gpio_free
drivers/pci/controller/dwc/pci-meson.c:540:48: error: 'GPIOD_OUT_LOW' undeclared (first use in this function); did you mean 'GPIOF_INIT_LOW'?
mp->reset_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_LOW);
^~~~~~~~~~~~~
GPIOF_INIT_LOW
Add the missing linux/gpio/consumer.h header to fix it.
Fixes: 9c0ef6d34f ("PCI: amlogic: Add the Amlogic Meson PCIe controller driver")
Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
[lorenzo.pieralisi@arm.com: commit log]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
We already need to zero out memory for dma_alloc_coherent(), as such
using dma_zalloc_coherent() is superflous. Phase it out.
This change was generated with the following Coccinelle SmPL patch:
@ replace_dma_zalloc_coherent @
expression dev, size, data, handle, flags;
@@
-dma_zalloc_coherent(dev, size, handle, flags)
+dma_alloc_coherent(dev, size, handle, flags)
Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
[hch: re-ran the script on the latest tree]
Signed-off-by: Christoph Hellwig <hch@lst.de>
- Mask DesignWare interrupts instead of disabling them to avoid lost
interrupts (Marc Zyngier)
- Add locking when acking DesignWare interrupts (Marc Zyngier)
- Ack DesignWare interrupts in the proper callbacks (Marc Zyngier)
* remotes/lorenzo/pci/dwc-msi:
PCI: dwc: Move interrupt acking into the proper callback
PCI: dwc: Take lock when ACKing an interrupt
PCI: dwc: Use interrupt masking instead of disabling
The MSI Enable bit in the MSI Capability (PCIe r4.0, sec 7.7.1.2) controls
whether a Function can request service using MSI.
i.MX6 Root Ports implement the MSI Capability and may use MSI to request
service for events like PME, hotplug, AER, etc. In addition, on i.MX6, the
MSI Enable bit controls delivery of MSI interrupts from components below
the Root Port.
Prior to f3fdfc4ac3 ("PCI: Remove host driver Kconfig selection of
CONFIG_PCIEPORTBUS"), enabling CONFIG_PCI_IMX6 automatically also enabled
CONFIG_PCIEPORTBUS, and when portdrv claimed the Root Ports, it set the MSI
Enable bit so it could use PME, hotplug, AER, etc. As a side effect, that
also enabled delivery of MSI interrupts from downstream components.
The imx6q-pcie driver itself does not depend on portdrv, so set MSI Enable
in imx6q-pcie so MSI from downstream components works even if nobody uses
MSI for the Root Port events.
Fixes: f3fdfc4ac3 ("PCI: Remove host driver Kconfig selection of CONFIG_PCIEPORTBUS")
Signed-off-by: Richard Zhu <hongxing.zhu@nxp.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Tested-by: Sven Van Asbroeck <TheSven73@googlemail.com>
Tested-by: Trent Piepho <tpiepho@impinj.com>
Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
A huge update this time, but a lot of that is just consolidating or
removing code:
- provide a common DMA_MAPPING_ERROR definition and avoid indirect
calls for dma_map_* error checking
- use direct calls for the DMA direct mapping case, avoiding huge
retpoline overhead for high performance workloads
- merge the swiotlb dma_map_ops into dma-direct
- provide a generic remapping DMA consistent allocator for architectures
that have devices that perform DMA that is not cache coherent. Based
on the existing arm64 implementation and also used for csky now.
- improve the dma-debug infrastructure, including dynamic allocation
of entries (Robin Murphy)
- default to providing chaining scatterlist everywhere, with opt-outs
for the few architectures (alpha, parisc, most arm32 variants) that
can't cope with it
- misc sparc32 dma-related cleanups
- remove the dma_mark_clean arch hook used by swiotlb on ia64 and
replace it with the generic noncoherent infrastructure
- fix the return type of dma_set_max_seg_size (Niklas Söderlund)
- move the dummy dma ops for not DMA capable devices from arm64 to
common code (Robin Murphy)
- ensure dma_alloc_coherent returns zeroed memory to avoid kernel data
leaks through userspace. We already did this for most common
architectures, but this ensures we do it everywhere.
dma_zalloc_coherent has been deprecated and can hopefully be
removed after -rc1 with a coccinelle script.
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Merge tag 'dma-mapping-4.21' of git://git.infradead.org/users/hch/dma-mapping
Pull DMA mapping updates from Christoph Hellwig:
"A huge update this time, but a lot of that is just consolidating or
removing code:
- provide a common DMA_MAPPING_ERROR definition and avoid indirect
calls for dma_map_* error checking
- use direct calls for the DMA direct mapping case, avoiding huge
retpoline overhead for high performance workloads
- merge the swiotlb dma_map_ops into dma-direct
- provide a generic remapping DMA consistent allocator for
architectures that have devices that perform DMA that is not cache
coherent. Based on the existing arm64 implementation and also used
for csky now.
- improve the dma-debug infrastructure, including dynamic allocation
of entries (Robin Murphy)
- default to providing chaining scatterlist everywhere, with opt-outs
for the few architectures (alpha, parisc, most arm32 variants) that
can't cope with it
- misc sparc32 dma-related cleanups
- remove the dma_mark_clean arch hook used by swiotlb on ia64 and
replace it with the generic noncoherent infrastructure
- fix the return type of dma_set_max_seg_size (Niklas Söderlund)
- move the dummy dma ops for not DMA capable devices from arm64 to
common code (Robin Murphy)
- ensure dma_alloc_coherent returns zeroed memory to avoid kernel
data leaks through userspace. We already did this for most common
architectures, but this ensures we do it everywhere.
dma_zalloc_coherent has been deprecated and can hopefully be
removed after -rc1 with a coccinelle script"
* tag 'dma-mapping-4.21' of git://git.infradead.org/users/hch/dma-mapping: (73 commits)
dma-mapping: fix inverted logic in dma_supported
dma-mapping: deprecate dma_zalloc_coherent
dma-mapping: zero memory returned from dma_alloc_*
sparc/iommu: fix ->map_sg return value
sparc/io-unit: fix ->map_sg return value
arm64: default to the direct mapping in get_arch_dma_ops
PCI: Remove unused attr variable in pci_dma_configure
ia64: only select ARCH_HAS_DMA_COHERENT_TO_PFN if swiotlb is enabled
dma-mapping: bypass indirect calls for dma-direct
vmd: use the proper dma_* APIs instead of direct methods calls
dma-direct: merge swiotlb_dma_ops into the dma_direct code
dma-direct: use dma_direct_map_page to implement dma_direct_map_sg
dma-direct: improve addressability error reporting
swiotlb: remove dma_mark_clean
swiotlb: remove SWIOTLB_MAP_ERROR
ACPI / scan: Refactor _CCA enforcement
dma-mapping: factor out dummy DMA ops
dma-mapping: always build the direct mapping code
dma-mapping: move dma_cache_sync out of line
dma-mapping: move various slow path functions out of line
...
This introduces specific glue layer for UniPhier platform to support
PCIe host controller that is based on the DesignWare PCIe core, and
this driver supports Root Complex (host) mode.
Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
The Amlogic Meson PCIe host controller is based on the Synopsys DesignWare
PCI core. This patch adds the driver support for Meson PCIe controller.
Link: https://lore.kernel.org/linux-pci/20181218224708.GB22610@google.com/
Signed-off-by: Yue Wang <yue.wang@amlogic.com>
Signed-off-by: Hanjie Lin <hanjie.lin@amlogic.com>
[lorenzo.pieralisi@arm.com: updated coding/comment style]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
The "lane" variant in struct mtk_pcie_port is not used, remove it.
Signed-off-by: Honghui Zhang <honghui.zhang@mediatek.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
The DWC PCIe core contains various separate register spaces: DBI, DBI2,
ATU, DMA, etc. The relationship between the addresses of these register
spaces is entirely determined by the implementation of the IP block, not
by the IP block design itself. Hence, the DWC driver must not make
assumptions that one register space can be accessed at a fixed offset from
any other register space. To avoid such assumptions, introduce an
explicit/separate register pointer for the ATU register space. In
particular, the current assumption is not valid for NVIDIA's T194 SoC.
The ATU register space is only used on systems that require unrolled ATU
access. This property is detected at run-time for host controllers, and
when this is detected, this patch provides a default value for atu_base
that matches the previous assumption re: register layout. An alternative
would be to update all drivers for HW that requires unrolled access to
explicitly set atu_base. However, it's hard to tell which drivers would
require atu_base to be set. The unrolled property is not detected for
endpoint systems, and so any endpoint driver that requires unrolled access
must explicitly set the iatu_unroll_enabled flag (none do at present), and
so a check is added to require the driver to also set atu_base while at
it.
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com>
Acked-by: Vidya Sagar <vidyas@nvidia.com>
Enable PCI suspend/resume support on imx6sx SOCs. This is similar to
imx7d with a few differences:
* The PM_Turn_Off bit is exposed through an IOMUX GPR, like all other
pcie control bits on 6sx.
* The pcie_inbound_axi clk needs to be turned off in suspend. On resume
it is restored via resume -> deassert_core_reset -> enable_ref_clk.
Most of the resume logic is shared with the initial reset after probe.
Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Acked-by: Lucas Stach <l.stach@pengutronix.de>
Add support for the gpio reset signal binding as described in the
designware-pcie.txt DT binding document. Both the documented
'reset-gpio' property name and the more standard 'reset-gpios' name are
supported.
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
The IMX6 PCI-e host driver also supports the IMX7d. However, the
Kconfig dependencies of the driver prevented it from being enabled
unless the kernel was built with both IMX6 and IMX7 support.
It works fine to build with only IMX7 support enabled therefore
adjust the Kconfig entry to allow this configuration.
Signed-off-by: Trent Piepho <tpiepho@impinj.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
Cc: Andrey Smirnov <andrew.smirnov@gmail.com>
Constify driver data since they do not get changed at runtime.
Signed-off-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
On some chips the PCIe and PCIE_PHY blocks are in separate power domains
which can be power-gated independently. The PCI driver needs to handle
this by keeping both domain active.
This is intended for imx6sx where PCIe is in DISPLAY and PCIE_PHY in
its own domain. Defining the DISPLAY domain requires a way for PCIe to
keep it active or it will break when displays are off.
The power-domains on imx6sx are meant to look like this:
power-domains = <&pd_disp>, <&pd_pci>;
power-domain-names = "pcie", "pcie_phy";
Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>
[lorenzo.pieralisi@arm.com: updated commit log]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
With the bypass support for the direct mapping we might not always have
methods to call, so use the proper APIs instead. The only downside is
that we will create two dma-debug entries for each mapping if
CONFIG_DMA_DEBUG is enabled.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Tested-by: Jesper Dangaard Brouer <brouer@redhat.com>
Tested-by: Tony Luck <tony.luck@intel.com>
The write to the status register is really an ACK for the HW,
and should be treated as such by the driver. Let's move it to the
irq_ack() callback, which will prevent people from moving it around
in order to paper over other bugs.
Fixes: 8c934095fa ("PCI: dwc: Clear MSI interrupt status after it is handled,
not before")
Fixes: 7c5925afbc ("PCI: dwc: Move MSI IRQs allocation to IRQ domains
hierarchical API")
Link: https://lore.kernel.org/linux-pci/20181113225734.8026-1-marc.zyngier@arm.com/
Reported-by: Trent Piepho <tpiepho@impinj.com>
Tested-by: Niklas Cassel <niklas.cassel@linaro.org>
Tested-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com>
Tested-by: Stanimir Varbanov <svarbanov@mm-sol.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
[lorenzo.pieralisi@arm.com: updated commit log]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: stable@vger.kernel.org
Bizarrely, there is no lock taken in the irq_ack() helper. This
puts the ACK callback provided by a specific platform in a awkward
situation where there is no synchronization that would be expected
on other callback.
Introduce the required lock, giving some level of uniformity among
callbacks.
Fixes: 7c5925afbc ("PCI: dwc: Move MSI IRQs allocation to IRQ domains
hierarchical API")
Link: https://lore.kernel.org/linux-pci/20181113225734.8026-1-marc.zyngier@arm.com/
Tested-by: Niklas Cassel <niklas.cassel@linaro.org>
Tested-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com>
Tested-by: Stanimir Varbanov <svarbanov@mm-sol.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
[lorenzo.pieralisi@arm.com: updated commit log]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: stable@vger.kernel.org
The dwc driver is showing an interesting level of brokeness, as it
insists on using the enable/disable set of registers to mask/unmask
MSIs, meaning that an MSIs being generated while the interrupt is in
that "disabled" state will simply be lost.
Let's move to the mask/unmask set of registers, which offers the
expected semantics.
Fixes: 7c5925afbc ("PCI: dwc: Move MSI IRQs allocation to IRQ domains
hierarchical API")
Link: https://lore.kernel.org/linux-pci/20181113225734.8026-1-marc.zyngier@arm.com/
Tested-by: Niklas Cassel <niklas.cassel@linaro.org>
Tested-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com>
Tested-by: Stanimir Varbanov <svarbanov@mm-sol.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
[lorenzo.pieralisi@arm.com: updated commit log]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: stable@vger.kernel.org
No users left except for vmd which just forwards it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Use the devm_of_pci_get_host_bridge_resources() API in place of the PCI OF
DT parser.
Signed-off-by: Honghui Zhang <honghui.zhang@mediatek.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Ryder Lee <ryder.lee@mediatek.com>
Fix an error caused by 3-bit right rotation on offset address
calculation of MSI-X table in dw_pcie_ep_raise_msix_irq().
The initial testing code was setting by default the offset address of
MSI-X table to zero, so that even with a 3-bit right rotation the
computed result would still be zero and valid, therefore this bug went
unnoticed.
Fixes: beb4641a78 ("PCI: dwc: Add MSI-X callbacks handler")
Signed-off-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com>
[lorenzo.pieralisi@arm.com: updated commit log]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: stable@vger.kernel.org
The order of parameters is not correct when invoking the outbound
window disable routine. Fix it.
Fixes: 4a2745d760 ("PCI: layerscape: Disable outbound windows configured by bootloader")
Signed-off-by: Hou Zhiqiang <Zhiqiang.Hou@nxp.com>
[lorenzo.pieralisi@arm.com: commit log]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: stable@vger.kernel.org
This bug was introduced in the interaction for two commits on either
branch of the merge commit 562df5c852 ("Merge branch
'pci/host-designware' into next").
Commit 4d107d3b5a ("PCI: imx6: Move link up check into
imx6_pcie_wait_for_link()"), changed imx6_pcie_wait_for_link() to poll
the link status register directly, checking for link up and not
training, and made imx6_pcie_link_up() only check the link up bit (once,
not a polling loop).
While commit 886bc5ceb5 ("PCI: designware: Add generic
dw_pcie_wait_for_link()"), replaced the loop in
imx6_pcie_wait_for_link() with a call to a new dwc core function, which
polled imx6_pcie_link_up(), which still checked both link up and not
training in a loop.
When these two commits were merged, the version of
imx6_pcie_wait_for_link() from 886bc5ceb5 was kept, which eliminated
the link training check placed there by 4d107d3b5a. However, the
version of imx6_pcie_link_up() from 4d107d3b5a was kept, which
eliminated the link training check that had been there and was moved to
imx6_pcie_wait_for_link().
The result was the link training check got lost for the imx6 driver.
Eliminate imx6_pcie_link_up() so that the default handler,
dw_pcie_link_up(), is used instead. The default handler has the correct
code, which checks for link up and also that it still is not training,
fixing the regression.
Fixes: 562df5c852 ("Merge branch 'pci/host-designware' into next")
Signed-off-by: Trent Piepho <tpiepho@impinj.com>
[lorenzo.pieralisi@arm.com: rewrote the commit log]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Joao Pinto <Joao.Pinto@synopsys.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Richard Zhu <hongxing.zhu@nxp.com>
The dw_pcie_host_ops structure is only stored in the ops field
of a pcie_port structure, and this field is const, so make the
dw_pcie_host_ops structure const as well.
Done with the help of Coccinelle.
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
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Merge tag 'pci-v4.20-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci
Pull PCI updates from Bjorn Helgaas:
- Fix ASPM link_state teardown on removal (Lukas Wunner)
- Fix misleading _OSC ASPM message (Sinan Kaya)
- Make _OSC optional for PCI (Sinan Kaya)
- Don't initialize ASPM link state when ACPI_FADT_NO_ASPM is set
(Patrick Talbert)
- Remove x86 and arm64 node-local allocation for host bridge structures
(Punit Agrawal)
- Pay attention to device-specific _PXM node values (Jonathan Cameron)
- Support new Immediate Readiness bit (Felipe Balbi)
- Differentiate between pciehp surprise and safe removal (Lukas Wunner)
- Remove unnecessary pciehp includes (Lukas Wunner)
- Drop pciehp hotplug_slot_ops wrappers (Lukas Wunner)
- Tolerate PCIe Slot Presence Detect being hardwired to zero to
workaround broken hardware, e.g., the Wilocity switch/wireless device
(Lukas Wunner)
- Unify pciehp controller & slot structs (Lukas Wunner)
- Constify hotplug_slot_ops (Lukas Wunner)
- Drop hotplug_slot_info (Lukas Wunner)
- Embed hotplug_slot struct into users instead of allocating it
separately (Lukas Wunner)
- Initialize PCIe port service drivers directly instead of relying on
initcall ordering (Keith Busch)
- Restore PCI config state after a slot reset (Keith Busch)
- Save/restore DPC config state along with other PCI config state
(Keith Busch)
- Reference count devices during AER handling to avoid race issue with
concurrent hot removal (Keith Busch)
- If an Upstream Port reports ERR_FATAL, don't try to read the Port's
config space because it is probably unreachable (Keith Busch)
- During error handling, use slot-specific reset instead of secondary
bus reset to avoid link up/down issues on hotplug ports (Keith Busch)
- Restore previous AER/DPC handling that does not remove and
re-enumerate devices on ERR_FATAL (Keith Busch)
- Notify all drivers that may be affected by error recovery resets
(Keith Busch)
- Always generate error recovery uevents, even if a driver doesn't have
error callbacks (Keith Busch)
- Make PCIe link active reporting detection generic (Keith Busch)
- Support D3cold in PCIe hierarchies during system sleep and runtime,
including hotplug and Thunderbolt ports (Mika Westerberg)
- Handle hpmemsize/hpiosize kernel parameters uniformly, whether slots
are empty or occupied (Jon Derrick)
- Remove duplicated include from pci/pcie/err.c and unused variable
from cpqphp (YueHaibing)
- Remove driver pci_cleanup_aer_uncorrect_error_status() calls (Oza
Pawandeep)
- Uninline PCI bus accessors for better ftracing (Keith Busch)
- Remove unused AER Root Port .error_resume method (Keith Busch)
- Use kfifo in AER instead of a local version (Keith Busch)
- Use threaded IRQ in AER bottom half (Keith Busch)
- Use managed resources in AER core (Keith Busch)
- Reuse pcie_port_find_device() for AER injection (Keith Busch)
- Abstract AER interrupt handling to disconnect error injection (Keith
Busch)
- Refactor AER injection callbacks to simplify future improvments
(Keith Busch)
- Remove unused Netronome NFP32xx Device IDs (Jakub Kicinski)
- Use bitmap_zalloc() for dma_alias_mask (Andy Shevchenko)
- Add switch fall-through annotations (Gustavo A. R. Silva)
- Remove unused Switchtec quirk variable (Joshua Abraham)
- Fix pci.c kernel-doc warning (Randy Dunlap)
- Remove trivial PCI wrappers for DMA APIs (Christoph Hellwig)
- Add Intel GPU device IDs to spurious interrupt quirk (Bin Meng)
- Run Switchtec DMA aliasing quirk only on NTB endpoints to avoid
useless dmesg errors (Logan Gunthorpe)
- Update Switchtec NTB documentation (Wesley Yung)
- Remove redundant "default n" from Kconfig (Bartlomiej Zolnierkiewicz)
- Avoid panic when drivers enable MSI/MSI-X twice (Tonghao Zhang)
- Add PCI support for peer-to-peer DMA (Logan Gunthorpe)
- Add sysfs group for PCI peer-to-peer memory statistics (Logan
Gunthorpe)
- Add PCI peer-to-peer DMA scatterlist mapping interface (Logan
Gunthorpe)
- Add PCI configfs/sysfs helpers for use by peer-to-peer users (Logan
Gunthorpe)
- Add PCI peer-to-peer DMA driver writer's documentation (Logan
Gunthorpe)
- Add block layer flag to indicate driver support for PCI peer-to-peer
DMA (Logan Gunthorpe)
- Map Infiniband scatterlists for peer-to-peer DMA if they contain P2P
memory (Logan Gunthorpe)
- Register nvme-pci CMB buffer as PCI peer-to-peer memory (Logan
Gunthorpe)
- Add nvme-pci support for PCI peer-to-peer memory in requests (Logan
Gunthorpe)
- Use PCI peer-to-peer memory in nvme (Stephen Bates, Steve Wise,
Christoph Hellwig, Logan Gunthorpe)
- Cache VF config space size to optimize enumeration of many VFs
(KarimAllah Ahmed)
- Remove unnecessary <linux/pci-ats.h> include (Bjorn Helgaas)
- Fix VMD AERSID quirk Device ID matching (Jon Derrick)
- Fix Cadence PHY handling during probe (Alan Douglas)
- Signal Cadence Endpoint interrupts via AXI region 0 instead of last
region (Alan Douglas)
- Write Cadence Endpoint MSI interrupts with 32 bits of data (Alan
Douglas)
- Remove redundant controller tests for "device_type == pci" (Rob
Herring)
- Document R-Car E3 (R8A77990) bindings (Tho Vu)
- Add device tree support for R-Car r8a7744 (Biju Das)
- Drop unused mvebu PCIe capability code (Thomas Petazzoni)
- Add shared PCI bridge emulation code (Thomas Petazzoni)
- Convert mvebu to use shared PCI bridge emulation (Thomas Petazzoni)
- Add aardvark Root Port emulation (Thomas Petazzoni)
- Support 100MHz/200MHz refclocks for i.MX6 (Lucas Stach)
- Add initial power management for i.MX7 (Leonard Crestez)
- Add PME_Turn_Off support for i.MX7 (Leonard Crestez)
- Fix qcom runtime power management error handling (Bjorn Andersson)
- Update TI dra7xx unaligned access errata workaround for host mode as
well as endpoint mode (Vignesh R)
- Fix kirin section mismatch warning (Nathan Chancellor)
- Remove iproc PAXC slot check to allow VF support (Jitendra Bhivare)
- Quirk Keystone K2G to limit MRRS to 256 (Kishon Vijay Abraham I)
- Update Keystone to use MRRS quirk for host bridge instead of open
coding (Kishon Vijay Abraham I)
- Refactor Keystone link establishment (Kishon Vijay Abraham I)
- Simplify and speed up Keystone link training (Kishon Vijay Abraham I)
- Remove unused Keystone host_init argument (Kishon Vijay Abraham I)
- Merge Keystone driver files into one (Kishon Vijay Abraham I)
- Remove redundant Keystone platform_set_drvdata() (Kishon Vijay
Abraham I)
- Rename Keystone functions for uniformity (Kishon Vijay Abraham I)
- Add Keystone device control module DT binding (Kishon Vijay Abraham
I)
- Use SYSCON API to get Keystone control module device IDs (Kishon
Vijay Abraham I)
- Clean up Keystone PHY handling (Kishon Vijay Abraham I)
- Use runtime PM APIs to enable Keystone clock (Kishon Vijay Abraham I)
- Clean up Keystone config space access checks (Kishon Vijay Abraham I)
- Get Keystone outbound window count from DT (Kishon Vijay Abraham I)
- Clean up Keystone outbound window configuration (Kishon Vijay Abraham
I)
- Clean up Keystone DBI setup (Kishon Vijay Abraham I)
- Clean up Keystone ks_pcie_link_up() (Kishon Vijay Abraham I)
- Fix Keystone IRQ status checking (Kishon Vijay Abraham I)
- Add debug messages for all Keystone errors (Kishon Vijay Abraham I)
- Clean up Keystone includes and macros (Kishon Vijay Abraham I)
- Fix Mediatek unchecked return value from devm_pci_remap_iospace()
(Gustavo A. R. Silva)
- Fix Mediatek endpoint/port matching logic (Honghui Zhang)
- Change Mediatek Root Port Class Code to PCI_CLASS_BRIDGE_PCI (Honghui
Zhang)
- Remove redundant Mediatek PM domain check (Honghui Zhang)
- Convert Mediatek to pci_host_probe() (Honghui Zhang)
- Fix Mediatek MSI enablement (Honghui Zhang)
- Add Mediatek system PM support for MT2712 and MT7622 (Honghui Zhang)
- Add Mediatek loadable module support (Honghui Zhang)
- Detach VMD resources after stopping root bus to prevent orphan
resources (Jon Derrick)
- Convert pcitest build process to that used by other tools (iio, perf,
etc) (Gustavo Pimentel)
* tag 'pci-v4.20-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (140 commits)
PCI/AER: Refactor error injection fallbacks
PCI/AER: Abstract AER interrupt handling
PCI/AER: Reuse existing pcie_port_find_device() interface
PCI/AER: Use managed resource allocations
PCI: pcie: Remove redundant 'default n' from Kconfig
PCI: aardvark: Implement emulated root PCI bridge config space
PCI: mvebu: Convert to PCI emulated bridge config space
PCI: mvebu: Drop unused PCI express capability code
PCI: Introduce PCI bridge emulated config space common logic
PCI: vmd: Detach resources after stopping root bus
nvmet: Optionally use PCI P2P memory
nvmet: Introduce helper functions to allocate and free request SGLs
nvme-pci: Add support for P2P memory in requests
nvme-pci: Use PCI p2pmem subsystem to manage the CMB
IB/core: Ensure we map P2P memory correctly in rdma_rw_ctx_[init|destroy]()
block: Add PCI P2P flag for request queue
PCI/P2PDMA: Add P2P DMA driver writer's documentation
docs-rst: Add a new directory for PCI documentation
PCI/P2PDMA: Introduce configfs/sysfs enable attribute helpers
PCI/P2PDMA: Add PCI p2pmem DMA mappings to adjust the bus offset
...
