Correct big-endian accesses to the CBUS UART, a Malta on-board discrete
TI16C550C part wired directly to the system controller's device bus, and
do not use byte swapping with the 32-bit accesses to the device.
The CBUS is used for devices such as the boot flash memory needed early
on in system bootstrap even before PCI has been initialised. Therefore
it uses the system controller's device bus, which follows the endianness
set with the CPU, which means no byte-swapping is ever required for data
accesses to CBUS, unlike with PCI.
The CBUS UART uses the UPIO_MEM32 access method, that is the `readl' and
`writel' MMIO accessors, which on the MIPS platform imply byte-swapping
with PCI systems. Consequently the wrong byte lane is accessed with the
big-endian configuration and the UART is not correctly accessed.
As it happens the UPIO_MEM32BE access method makes use of the `ioread32'
and `iowrite32' MMIO accessors, which still use `readl' and `writel'
respectively, however they byte-swap data passed, effectively cancelling
swapping done with the accessors themselves and making it suitable for
the CBUS UART.
Make the CBUS UART switch between UPIO_MEM32 and UPIO_MEM32BE then,
based on the endianness selected. With this change in place the device
is correctly recognised with big-endian Malta at boot, along with the
Super I/O devices behind PCI:
Serial: 8250/16550 driver, 5 ports, IRQ sharing enabled
printk: console [ttyS0] disabled
serial8250.0: ttyS0 at I/O 0x3f8 (irq = 4, base_baud = 115200) is a 16550A
printk: console [ttyS0] enabled
printk: bootconsole [uart8250] disabled
serial8250.0: ttyS1 at I/O 0x2f8 (irq = 3, base_baud = 115200) is a 16550A
serial8250.0: ttyS2 at MMIO 0x1f000900 (irq = 20, base_baud = 230400) is a 16550A
Fixes: e7c4782f92 ("[MIPS] Put an end to <asm/serial.h>'s long and annyoing existence")
Cc: stable@vger.kernel.org # v2.6.23+
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2106260524430.37803@angie.orcam.me.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The SMSC FDC37M817 Super I/O chip has a configuration feature that lets
it support special UART divisor values of 32770 and 32769 for bit rates
of 230400 and 460800 bits per second respectively. Our 8250 driver core
provides support for these special divisors via the UPF_MAGIC_MULTIPLIER
flag, and YAMON firmware unconditionally configures the Super I/O chip
with these divisors enabled as well, so all we need to do in platform
setup for these bit rates to work is to set the flag.
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2105182249380.3032@angie.orcam.me.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Historically a lot of these existed because we did not have
a distinction between what was modular code and what was providing
support to modules via EXPORT_SYMBOL and friends. That changed
when we forked out support for the latter into the export.h file.
This means we should be able to reduce the usage of module.h
in code that is obj-y Makefile or bool Kconfig. In the case of
some code where it is modular, we can extend that to also include
files that are building basic support functionality but not related
to loading or registering the final module; such files also have
no need whatsoever for module.h
The advantage in removing such instances is that module.h itself
sources about 15 other headers; adding significantly to what we feed
cpp, and it can obscure what headers we are effectively using.
Since module.h might have been the implicit source for init.h
(for __init) and for export.h (for EXPORT_SYMBOL) we consider each
instance for the presence of either and replace/add as needed.
Also note that MODULE_DEVICE_TABLE is a no-op for non-modular code.
Build coverage of all the mips defconfigs revealed the module.h
header was masking a couple of implicit include instances, so
we add the appropriate headers there.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: David Daney <david.daney@cavium.com>
Cc: John Crispin <john@phrozen.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: "Steven J. Hill" <steven.hill@cavium.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/15131/
[james.hogan@imgtec.com: Preserve sort order where it already exists]
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Add the DT nodes required to probe the CFI compatible parallel monitor
flash found on the Malta development board, and remove the platform
code that was previously doing it. Delete the now-empty malta-platform.c
file. Adjust the Malta defconfigs that enable MTD & the pflash/CFI
driver to enable CONFIG_MTD_PHYSMAP_OF rather than CONFIG_MTD_PHYSMAP in
order to preserve their behaviour.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: linux-mips@linux-mips.org
Cc: devicetree@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14278/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Commit 225ae5fd9a
"MIPS: Malta: Fix interupt number of CBUS UART"
fixed the IRQ number for the ttyS2 CBUS UART. However, this now
conflicts with the GIC IPI1 interrupt in CMP platforms. The Malta
interrupt code arbitrarily binds IPIs to INT2 and INT3 and since
ttyS2 uses the INT2 IRQ line, closing the device disables the
INT2 interrupt and this effectively disables the IPI1 interrupt
as well. This patch is mainly a workaround until the Malta code
is fixed properly.
Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Signed-off-by: John Crispin <blogic@openwrt.org>
Patchwork: http://patchwork.linux-mips.org/patch/6045/
Having received another series of whitespace patches I decided to do this
once and for all rather than dealing with this kind of patches trickling
in forever.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The CBUS UART's interrupt number was wrong conflicting with the interrupt
being tied to the Intel PIIX4. Since the PIIX4's interrupt is registered
before the CBUS UART which is not being used on most systems this would
not be noticed.
Attempts to open the ttyS2 CBUS UART would result in:
genirq: Flags mismatch irq 18. 00000000 (serial) vs. 00010000 (XT-PIC cascade)
serial_link_irq_chain: request failed: -16 for irq: 18
Qemu was written to match the kernel so will need to be fixed also.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
YAMON requires and enforces the RTC Data Mode (Register B, DM bit) to
binary, that is the bit is set every time the board goes through the
firmware bootstrap sequence. Likewise its calendar manipulation commands
interpret or set the RTC registers unconditionally as binary, never
actually checking what the value of the DM bit is, under the (correct)
assumption that it has been previously set, to indicate the binary mode.
A change to Linux a while ago however introduced a platform-specific
tweak that clears that bit and therefore forces the data mode to BCD.
This causes clock corruption and misinterpretation that has to be fixed up
by user-mode tools in system startup scripts as the initial clock is often
incorrect according to the BCD interpretation forced.
This change removes the hack; a comment included refers to alarm code,
but even if it was broken at one point by requiring the BCD mode, it
should have been trivially corrected and even if not, given how rarely the
alarm feature is used, that was not really a reasonable justification to
break the system clock that is indeed used by virtually everything. And
either way the alarm code has been since fixed anyway.
Signed-off-by: Maciej W. Rozycki <macro@codesourcery.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/4336/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Add missing #inclusions of <linux/irq.h> to a whole bunch of files that should
really include it. Note that this can replace #inclusions of <asm/irq.h>.
This is required for the patch to sort out irqflags handling function naming to
compile on MIPS.
The problem is that these files require access to things like setup_irq() -
which isn't available by #including <linux/interrupt.h>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
With the conversion of MIPS to RTC_LIB the old RTC driver CONFIG_RTC became
unselectable. Fix by setting up a platform device. Also enable
RTC_CLASS so system time gets set from RTC on kernel initialization.
[Ralf: Original patch by Tiejun; polished nice and shiny by me]
Signed-off-by: Tiejun Chen <tiejun.chen@windriver.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
