In case the link is down, or the controller driver is removed before
booting the next stage, shut down the PCIe link, put both the remote
PCIe device and the controller into reset, and disable clock. This
way, the hardware is not left active when not in use.
Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org>
R-Car V4H Reference Manual R19UH0186EJ0130 Rev.1.30 Apr. 21, 2025 page 585
Figure 9.3.2 Software Reset flow (B) indicates that for peripherals in HSC
domain, after reset has been asserted by writing a matching reset bit into
register SRCR, it is mandatory to wait 1ms.
Because it is the controller driver which can determine whether or not the
controller is in HSC domain based on its compatible string, add the missing
delay into the controller driver.
This 1ms delay is documented on R-Car V4H and V4M, it is currently unclear
whether S4 is affected as well. This patch does apply the extra delay on
R-Car S4 as well.
Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org>
Assure the reset is latched and the core is ready for DBI access.
On R-Car V4H, the PCIe reset is asynchronized and does not take
effect immediately, but needs a short time to complete. In case
DBI access happens in that short time, that access generates an
SError. Make sure that condition can never happen, read back the
state of the reset which should turn the asynchronized reset into
synchronized one, and wait a little over 1ms to add additional
safety margin.
Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org>
R-Car V4H Reference Manual R19UH0186EJ0130 Rev.1.30 Apr. 21, 2025 page 4581
Figure 104.3b Initial Setting of PCIEC(example), third quarter of the figure
indicates that register 0xf8 should be polled until bit 18 becomes set to 1.
Register 0xf8 bit 18 is 0 immediately after write to PCIERSTCTRL1 and is set
to 1 in less than 1 ms afterward. The current readl_poll_timeout() break
condition is inverted and returns when register 0xf8 bit 18 is set to 0,
which in most cases means immediately. In case CONFIG_DEBUG_LOCK_ALLOC=y ,
the timing changes just enough for the first readl_poll_timeout() poll to
already read register 0xf8 bit 18 as 1 and afterward never read register
0xf8 bit 18 as 0, which leads to timeout and failure to start the PCIe
controller.
Fix this by inverting the poll condition to match the reference manual
initialization sequence.
Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org>
R-Car V4H Reference Manual R19UH0186EJ0130 Rev.1.30 Apr. 21, 2025
page 4581 Figure 104.3b Initial Setting of PCIEC(example) middle
of the figure indicates that fourth write into register 0x148 [2:0]
is 0x3 or GENMASK(1, 0). The current code writes GENMASK(11, 0)
which is a typo. Fix the typo.
Fixes: be3dd0dc2fd9 ("pci: pcie-rcar-gen4: Add Renesas R-Car Gen4 DW PCIe controller driver")
Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org>
Add R-Car Gen4 PCIe controller support for host mode.
This controller is based on Synopsys DesignWare PCIe. However, this
particular controller has a number of vendor-specific registers, and as
such, requires initialization code, including PHY firmware loading.
The PHY firmware loading is implemented in an entirely generic manner,
by calling a firmware loading script, which the user can configure in
a way they require. This provides the user with flexibility of loading
the PCIe firmware from whichever storage device they need to load it
from.
Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org>
