At least with Tx FIFO enabled it shows me ~10% reduction of verbose boot
time with serial console at 115200 baud.
Reviewed by: marcel
MFC after: 2 weeks
hardware but lack the larger fifos rev 5 hardware should have.
The linux world (where our FDT data comes from) solved this by adding
a new property to pl011 nodes, "arm,primecell-periphid". When this
property is present, its values override the values in the hardware
periphid registers. For pl011 rev 5 hardware with small fifos, they
override the id so that it appears to be rev 4 hardware.
The driver now uses the new property when present. It also continues
to check the device compat string, to handle older fdt data that may
still be in use on existing systems (on RPi systems it is common to
update system software without updating fdt data which is part of the
boot firmware).
Reviewed by: imp
Starting with rev 5 (which is inexplicably indicated by a version number
of '3' in the Peripheral ID register), the pl011 doubled the size of the
rx and tx fifos, to 32 bytes, so read the ID register and set the size
variables in the softc accordingly.
An interesting wrinkle in this otherwise-simple concept is that the
bcm2835 SoC, used in Raspberry Pi systems among others, has the rev 5
pl011 hardware, but somehow also has the older 16-byte fifos. We check
the FDT data to see if the hardware is part of a bcm283x system and use
the smaller size if so.
Thanks to jchandra@ for pointing out that newer hardware has bigger fifos.
have been in the code all along, but were masked by having a fifo depth of
one byte at the hardware level, so everything kinda worked by accident.
The hardware interrupts when the TX fifo is half empty, so set
sc->sc_txfifosz to 8 bytes (half the hardware fifo size) to match. This
eliminates dropped characters on output.
Restructure the read loop to consume all the bytes in the fifo by using
the "rx fifo empty" bit of the flags register rather than the "rx ready"
bit of the interrupt status register. The rx-ready interrupt is cleared
when the number of bytes in the fifo fall below the interrupt trigger
level, leaving the fifo half full every time receive routine was called.
Now it loops until the fifo is completely empty every time (including
when the function is called due to a receive timeout as well as for
fifo-full).
This is required for FDT's standard "reg-io-width" property
(similar to "reg-shift" property) found in many DTS files.
This fixes operation on Altera Arria 10 SOC Development Kit,
where standard ns8250 uart allows 4-byte access only.
Reviewed by: kan, marcel
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D9785
The pl011 UART has a 16 entry Tx FIFO and a 16 entry Rx FIFO that
have not been used so far. Update the driver to enable the FIFOs
and use them in transmit and receive.
Reviewed by: andrew
Differential Revision: https://reviews.freebsd.org/D8819
Do this here as puc(4) disallows single-port instances; at least
one multi-port PCIe UART chip (in this case, the ASIX MCS9922)
present separate PCI configuration space (functions) for each UART.
Tested using lrzsz and a null-modem cable. The ExpressCard/34
variants containing the MCS9922 should also use MSI with this change.
Reviewed by: jhb, imp, rpokala
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D9123
Remove unused fields from uart_pl011_softc. Add an interrupt mask
field to the softc and use it to set the interrupt mask register.
There should be no functional change introduced here except in the
grab and ungrab functions. In these functions, we now disable and
enable all interrupts rather than just the receive interrupt.
Clear the interrupt state before reading the input char from the
input FIFO. In the current code there is a window between the read
to the data register and the write to the the ICR, during which an
input char will not cause an interrupt.
This fixes the issue by which the serial port input on QEMU freezes
when using the emulated pl011 serial port.
uart we need to handle both it and FDT, and as such we need to have an
architecture specific driver.
Obtained from: ABT Systems Ltd
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D7796
Do not assume that all uart drivers use uart_softc structure as is.
Some do a sensible thing and do declare their uart class and driver
properly and arrive into uart_bus_attach with suitably sized softc.
Submitted by: kan
Sponsored by: DARPA, AFRL
Summary:
Some device trees put "fsl,ns16650" first in the compatible list. This causes
the probe code to choke, even though the device is compatible with ns16650, and
has it listed later in the tree.
Reviewed by: nwhitehorn
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D7676
* Add acpi_if.h to the SRC list in the uart module
* Only include new acpi headers when they are needed
Obtained from: ABT Systems Ltd
MFC after: 1 month
Sponsored by: The FreeBSD Foundation
the uart class to use in a similar way as the fdt driver.
Obtained from: ABT Systems Ltd
MFC after: 1 month
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D7248
and ACPI. As such pull out what will be the common parts of the FDT cpu
detection to a new function that can be shared between them.
Reviewed by: manu
Obtained from: ABT Systems Ltd
MFC after: 1 month
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D7262
In some cases, the driver must handle given properties located in
specific OF subnode. Instead of creating duplicate set of function, add
'node' as argument to existing functions, defaulting it to device OF node.
MFC after: 3 weeks
separate driver. Add support for activating clock and hwreset resources
for these devices when the EXT_RESOURCES option is present.
Reviewed by: andrew, mmel, Emmanuel Vadot <manu@bidouilliste.com>
Approved by: adrian (mentor)
Differential Revision: https://reviews.freebsd.org/D5749
the bus space tag and handle for a uart console, use the values returned by
that routine to set the global uart_bus_space_mem, instead of assuming that
there will be a global variable named fdtbus_bs_tag to set it from.
Also, use OF_getencprop() instead calling fdt32_to_cpu() separately.
will allow for code that uses the old fdt_get_range and fdt_regsize
functions to find a range, map it, access, then unmap to replace this, up
to and including the map, with a call to OF_decode_addr.
As this function should only be used in the early boot code the unmap is
mostly do document we no longer need the mapping as it's a no-op, at least
on arm.
Reviewed by: jhibbits
Sponsored by: ABT Systems Ltd
Differential Revision: https://reviews.freebsd.org/D5258
uart_dev_ns8250 now relies on compatible property instead of additional
'busy-detect' cell. All drivers with compatible = "snps,dw-apb-uart" have
busy detection turned on. DTS files of devices affected by the change
were modified and 'busy-detect' property was removed.
Reviewed by: andrew, ian, imp
Obtained from: Semihalf
Sponsored by: Stormshield
Submitted by: Bartosz Szczepanek <bsz@semihalf.com>
Differential revision: https://reviews.freebsd.org/D4218
This compatibility string is used in .dts file of Armada38x
and isrequired for driver attachment.
Reviewed by: andrew, ian, imp
Obtained from: Semihalf
Sponsored by: Stormshield
Submitted by: Michal Stanek <mst@semihalf.com>
Differential revision: https://reviews.freebsd.org/D4216
to actually wait until the TX FIFOs of UARTs have be drained before
returning. This is done by bringing the equivalent of the TS_BUSY flag
found in the previous implementation back in an ABI-preserving way.
Reported and tested by: Patrick Powell
Most likely, drivers for USB-serial-adapters likewise incorporating
TX FIFOs as well as other terminal devices that buffer output in some
form should also provide implementations of tsw_busy.
MFC after: 3 days
on FDT/OFW platforms.
After the refactoring of the powerpc code so that OF_decode_addr() is usable
on all FDT/OFW platforms, this switches uart(4) to using it.
Differential Revision: https://reviews.freebsd.org/D4675
