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>
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>
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>
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>
When the root complex suspends it must send a PME_Turn_Off TLP.
Implement this by asserting the "turnoff" reset.
On imx7d this functionality is part of the System Reset Controller (SRC)
and is exposed through the linux reset-controller subsystem.
On imx6 equivalent bits are in the IOMUXC pinmux controller General
Purpose Register (GPR) area which the imx6-pcie driver accesses
directly.
This is only for imx7d right now but it's deliberately implemented as an
optional reset, ignoring the chip variant:
* Older dtbs won't have this reset so it will be ignored.
* Future chips might also expose this as a reset controller.
For example imx8m (not yet supported) has the exact same
PCIE_CTRL_APPS_TURNOFF bit in the same location.
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: Lucas Stach <l.stach@pengutronix.de>
On imx7d the pcie-phy power domain is turned off in suspend and this can
make the system hang after resume when attempting any read from PCI.
Fix this by adding minimal suspend/resume code. This will prepare for
powering down on suspend and reset the block on resume.
Code is only for imx7d but a very similar sequence can be used for
other SOCs.
Original-by: Richard Zhu <hongxing.zhu@nxp.com>
Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>
[lorenzo.pieralisi@arm.com: commit log update]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
The power up defaults of the MPLL are designed for the standard 125MHz
refclock derived from the ENET PLL. As this clock has a jitter that
violates the PCIe Gen2 timing requirements, some board designs use
an external reference clock generator. Those clock generators may
output a clock at a different rate than what the MPLL expects
(usually a 100MHz clock, to re-use the PCIe bus clock).
In that case the MPLL must be reconfigured via overrides to use
different refclock dividers and loop multipliers. The i.MX6
reference manual lists both 100MHz and 200MHz as supported refclock
rates and the associated mult and div values.
Only the 100MHz setup has been tested on a real board, but since the
200MHz setup only differs in the used pre-divider it seems safe to
add it now.
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Richard Zhu <hongxing.zhu@nxp.com>
Function dw_pcie_host_init() already initializes the root_bus_nr field
of 'struct pcie_port', so the -1 assignment prior to calling
dw_pcie_host_init() in platform specific driver is not really needed.
Drop it.
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
Cc: Richard Zhu <hongxing.zhu@nxp.com>
Cc: Lucas Stach <l.stach@pengutronix.de>
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.com
Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
[bhelgaas: changelog]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>