According to the IMX6 reference manuals, REF_SSP_EN (Reference clock enable
for SS function) must remain deasserted until the reference clock is
running at the appropriate frequency.
Delay enabling the reference clock for the SS function until it has
stabilized. This prevents a high link failure rate (>5%) on certain IMX6
boards at various temperatures.
[bhelgaas: reword changelog slightly]
Tested-by: Fabio Estevam <festevam@gmail.com>
Signed-off-by: Tim Harvey <tharvey@gateworks.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Marek Vasut <marex@denx.de>
Acked-by: Lucas Stach <l.stach@pengutronix.de>
This effectively reverts f216f57ffe ("PCI: imx6: Probe the PCIe in
fs_initcall()") as the resource allocation issue that prevented the driver
from working properly at module_initcall level is now fixed in
pcie-designware.c.
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Richard Zhu <r65037@freescale.com>
This fixes a boot hang observed when the bootloader already enabled the
PCIe link for its own use. The fundamental problem is that Freescale
forgot to wire up the core reset, so software doesn't have a sane way to
get the core into a defined state.
According to the DW PCIe core reference manual, configuration of the core
may only happen when the LTSSM is disabled, so this is one of the first
things we need to do. Apparently this isn't safe to do when the LTSSM is in
any state other than "detect" as we observe an instant machine hang when
trying to do so while the link is already up.
As a workaround, force LTSSM into detect state right before hitting the
disable switch. There is still a race window because the LTSSM may
transition out of "detect" before we can disable it, but it's the best
we can do for now.
[bhelgaas: mention race window]
Link: http://lkml.kernel.org/r/1406830565-23450-3-git-send-email-l.stach@pengutronix.de
Reported-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Tim Harvey <tharvey@gateworks.com>
* pci/host-designware:
PCI: designware: Remove unnecessary use of 'conf_lock' spinlock
PCI: designware: Use new OF interrupt mapping when possible
PCI: designware: Fix iATU programming for cfg1, io and mem viewport
PCI: designware: Fix comment for setting number of lanes
* pci/host-imx6:
PCI: designware: Split Exynos and i.MX bindings
* pci/host-mvebu:
PCI: mvebu: Use '%pa' for printing 'phys_addr_t' type
PCI: mvebu: Remove unnecessary use of 'conf_lock' spinlock
PCI: mvebu: split PCIe BARs into multiple MBus windows when needed
bus: mvebu-mbus: allow several windows with the same target/attribute
bus: mvebu-mbus: Avoid setting an undefined window size
PCI: mvebu: fix off-by-one in the computed size of the mbus windows
* pci/host-tegra:
PCI: tegra: Use new OF interrupt mapping when possible
imx6_add_pcie_port() is called only from from imx6_pcie_probe() which is
annotated with __init. Thus it makes sense to annotate
imx6_add_pcie_port() with __init to avoid section mismatch warnings.
[bhelgaas: changelog]
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Sean Cross <xobs@kosagi.com>
This patch handles the case where the PCIe link is up and running, yet
drops into the LTSSM training mode. The link spends short time in the LTSSM
training mode, but the current code can misinterpret it as the link being
stalled. Waiting for the LTSSM training to complete fixes the issue.
Quoting Sascha:
This is broken since commit 7f9f40c01c ('PCI: imx6: Report "link up"
only after link training completes').
The designware driver changes the PORT_LOGIC_SPEED_CHANGE bit in
dw_pcie_host_init() which causes the link to be retrained. During the
next call to dw_pcie_rd_conf() the link is then reported being down and
the function returns PCIBIOS_DEVICE_NOT_FOUND resulting in nonfunctioning
PCIe.
Fixes: 7f9f40c01c (PCI: imx6: Report "link up" only after link training completes)
Tested-by: Troy Kisky <troy.kisky@boundarydevices.com>
Tested-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Marek Vasut <marex@denx.de>
Signed-off-by: Troy Kisky <troy.kisky@boundarydevices.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
There is no need to use 'goto err' as we can directly return the errors.
No functional change.
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
When using devm_ioremap_resource(), we do not need to check the return
value of platform_get_resource(), so just remove it.
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Marek Vasut <marex@denx.de>
imx6_pcie_of_match is always compiled in because PCI_IMX6 depends on
SOC_IMX6Q, which only supports OF build. Hence of_match_ptr is not
required.
[bhelgaas: add changelog details from Shawn]
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Cc: Sean Cross <xobs@kosagi.com>
A longer link startup timeout is required when certain PCI switches are
attached to the root complex. This was tested with a Pericom switch
and a PLX switch.
Signed-off-by: Marek Vasut <marex@denx.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Tim Harvey <tharvey@gateworks.com>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
An imprecise abort is triggered when a port behind a switch is accessed
and no device is present. At enumeration, imprecise aborts are not enabled
thus this ends up getting deferred until the kernel has completed init. At
that point we must not adjust PC - the handler must do nothing, but a
handler must exist.
This fixes random crashes that occur right after freeing init.
Tested-by: Marek Vasut <marex@denx.de>
Signed-off-by: Tim Harvey <tharvey@gateworks.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Acked-by: Marek Vasut <marex@denx.de>
Add support for the PCIe port present on the i.MX6 family of controllers.
These use the Synopsis Designware core tied to their own PHY.
Signed-off-by: Sean Cross <xobs@kosagi.com>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
