The ARM compiler inserts calls to __aeabi_idiv() and
__aeabi_uidiv() when it needs to perform division on signed and
unsigned integers. If a processor has support for the sdiv and
udiv instructions, the kernel may overwrite the beginning of those
functions with those instructions and a "bx lr" to get better
performance.
To ensure that those functions are aligned to a 32-bit word for easier
patching (which might not always be the case in Thumb mode) and that
the two patched instructions end up in the same cache line, a 8-byte
alignment is enforced when ARM_PATCH_IDIV is selected.
This was heavily inspired by a previous patch from Stephen Boyd.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Use PTR_ERR_OR_ZERO rather than if(IS_ERR(...)) + PTR_ERR
Signed-off-by: Prasanna Karthik <mkarthi3@visteon.com>
Signed-off-by: Nathan Lynch <nathan_lynch@mentor.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The proc-v7.S code uses a small temporary stack to preserve register
content in its setup code. This stack is located in the .text section
which is normally meant to be read-only.
Move that temporary stack to the .bss section and get its address in
a position independent way, similarly to what we do in other parts
of the kernel.
While at it, one comments was updated to reflect reality, and the list
of saved registers in the proc-v7.S case is updated to match the comment
next to it for coherency.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
All platforms that used to define an sci_fck clock have now switched to
the fck name. Remove the fallback code.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Acked-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The SCIF variant in the sh7734 SoC is not the common "SH-4(A)" variant,
but a derivative with added "Baud Rate Generator for External Clock"
(BRG). Correct the regtype value in platform data to fix this.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
The sh-sci driver falls back to the peripheral clock if the sci_ick
clock doesn't exist. There's thus no need to create an alias for the
peripheral clock named sci_ick.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Acked-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
The SCI driver requires a functional clock named "fck" and falls back to
"sci_ick" or "sci_fck" when the "fck" clock doesn't exist. To allow
removal of the fallback code rename the sci_ick and sci_fck clocks to
fck for all SH platforms.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Acked-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Add support for using the Baud Rate Generator for External Clock (BRG), as
found on some SCIF and HSCIF variants, to provide the sampling clock.
This can improve baud rate range and accuracy.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add support for using the SCIx clock pin "(H)SCK" as an external clock
input on (H)SCI(F), providing the sampling clock.
Note that this feature is not yet supported on the select SCIFA variants
that also have it (e.g. sh7723, sh7724, and r8a7740).
On (H)SCIF variants with an External Baud Rate Generator (BRG), the
BRG Clock Select Register must be configured for the external clock.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Refactor the clock and baud rate parameter code to ease adding support
for multiple sampling clock sources.
sci_scbrr_calc() now returns the bit rate error, so it can be compared
to the bit rate error using other sampling clock sources.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The "renesas,scif" compatible value is currently used for the SCIF
variant in all Renesas SoCs of the R-Car family. However, the variant
used in the R-Car family is not the common "SH-4(A)" variant, but a
derivative with added "Baud Rate Generator for External Clock" (BRG),
which is also present in sh7734.
Use the family-specific SCIF compatible values for R-Car Gen1, Gen2, and
Gen3 SoCs to differentiate. The "renesas,scif" compatible value can
still be used as a common denominator for SCIF variants with the
"SH-4(A)" register layout (i.e. ignoring the "Serial Extension Mode
Register" (SCEMR) and the new BRG-specific registers).
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The "renesas,scif" compatible value is currently used for the SCIF
variant in all Renesas SoCs of the R-Car and RZ families. However, the
variant used in the RZ family is not the common "SH-4(A)" variant, but
the "SH-2(A) with FIFO data count register" variant, as it has the
"Serial Extension Mode Register" (SCEMR), just like on sh7203, sh7263,
sh7264, and sh7269.
Use the (already documented) SoC-specific "renesas,scif-r7s72100"
compatible value to differentiate. The "renesas,scif" compatible value
can still be used as a common denominator for SCIF variants with the
"SH-4(A)" register layout (i.e. ignoring the SCEMR register).
Note that currently both variants are treated the same, but this may
change if support for the SCEMR register is ever added.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Store the encoded port and register types directly in of_device_id.data,
instead of using a pointer to a structure.
This saves memory and simplifies the source code, especially when adding
more compatible entries later.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add register definitions for the Baud Rate Generator for External Clock
(BRG), as found in some SCIF and in HSCIF, including a new regtype for
the "SH-4(A)"-derived SCIF variant with BRG.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The maximum baud rate depends on the sampling rate.
HSCIF has a variable sampling rate and sets s->sampling_rate to zero,
hence use the minimum sampling rate of 8.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
For low bit rates, the for-loop that reduces the divider returned by
sci_scbrr_calc() and picks the clock select value may terminate without
finding suitable values, leading to out-of-range divider and clock
select values.
sci_baud_calc_hscif() doesn't suffer from this problem, as it correctly
uses clamp().
Since there are only two relevant differences between HSCIF and other
variants w.r.t. bit rate configuration (fixed vs. variable sample rate,
and an additional factor of two), sci_scbrr_calc() and
sci_baud_calc_hscif() can be merged, fixing the issue with out-of-range
values.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When assuming D = 0.5 and F = 0, maximizing the receive margin M is
equivalent to maximizing the sample rate N.
Hence there's no need to calculate the receive margin, as we can obtain
the same result by iterating over all possible sample rates in reverse
order, and skipping parameter sets that don't provide a lower bit rate
error.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The algorithm to find the best parameters for the requested bit rate
calculates the relative bit rate error, using "(br * scrate) / 1000".
For small "br * scrate", this has two problems:
- The quotient may be zero, leading to a division by zero error,
- This may introduce a large rounding error.
Switch from relative to absolute bit rate error calculation to fix this.
The default baud rate generator values can be removed, as there will
always be one set of values that gives the smallest absolute error.
Print the best set of values when debugging.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If bps >= 1048576, the multiplication of the predivider and "bps" will
overflow, and both br and err will contain bogus values.
Skip the current and all higher clock select predividers when overflow
is detected. Simplify the calculations using intermediates while we're
at it.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Move the -1 offset of br to the assignment to *brr, so br cannot become
negative anymore, and update the clamp() call. Now all unsigned values
in sci_baud_calc_hscif() can become unsigned.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Blindly writing the default configuration value into the SCSCR register
may change the clock selection bits, breaking the serial console if the
current driver settings differ from the default settings.
Keep the current clock selection bits to prevent this from happening
on e.g. r8a7791/koelsch when support for the BRG will be added.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
As F is assumed to be zero in the receive margin formula, frame_len is
not used. Remove it, together with the sci_baud_calc_frame_len() helper
function.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Amend the DT bindings to include the optional clock sources for the Baud
Rate Generator for External Clock (BRG), as found on some SCIF variants
and on HSCIF.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Amend the DT bindings to include the optional external clock on
(H)SCI(F) and some SCIFA, where this pin can serve as a clock input,
depending on board wiring.
Clarify the use of the divided functional clock as a source for the
sampling clock.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add fallback compatibility strings for R-Car Gen1, Gen2, and Gen3.
This is in keeping with the fallback scheme being adopted wherever
appropriate for drivers for Renesas SoCs.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
As no platform defines an interface clock the SCI driver always falls
back to a clock named "peripheral_clk".
- On SH platforms that clock is the base clock for the SCI functional
clock and has the same frequency,
- On ARM platforms that clock doesn't exist, and clk_get() will return
the default clock for the device.
We can thus make the functional clock mandatory and drop the interface
clock.
EPROBE_DEFER is handled for clocks that may be referenced from DT (i.e.
"fck", and the deprecated "sci_ick").
Cc: devicetree@vger.kernel.org
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Acked-by: Simon Horman <horms+renesas@verge.net.au>
[geert: Handle EPROBE_DEFER, reformat description, break long comment line]
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When running on newer OPAL firmware that supports sending extra
OPAL_MSG types, we would print a warning on *every* message received.
This could be a problem for kernels that don't support OPAL_MSG_OCC
on machines that are running real close to thermal limits and the
OCC is throttling the chip. For a kernel that is paying attention to
the message queue, we could get these notifications quite often.
Conceivably, future message types could also come fairly often,
and printing that we didn't understand them 10,000 times provides
no further information than printing them once.
Cc: stable@vger.kernel.org
Signed-off-by: Stewart Smith <stewart@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The RVDA and RVDS (raw VBT data address and size) fields of the ASLE
mailbox may specify an alternate location for VBT instead of mailbox #4.
Use the alternate location if available and valid, falling back to
mailbox #4 otherwise.
v2: Update debug logging (Ville)
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Tested-by: Mika Kahola <mika.kahola@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1450178280-28020-1-git-send-email-jani.nikula@intel.com
Commit 6271897978 ("Makefile: Document ability to make file.lst
and file.S") document ability to make file.S, but there isn't such
ability in kbuild, so revert it.
Signed-off-by: Wang YanQing <udknight@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.com>
NX842 coprocessor sets 3rd bit in CR register with XER[S0] which is
nothing to do with NX request. Since this bit can be set with other
valuable return status, mast this bit.
One of other bits (INITIATED, BUSY or REJECTED) will be returned for
any given NX request.
Signed-off-by: Haren Myneni <haren@us.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The common I/O layer may pass an error value as the irb in the device's
interrupt handler (for classic channel I/O). This won't happen in
current virtio-ccw implementations, but it's better to be safe than
sorry.
Let's just return the error conveyed by the irb and clear any possible
pending I/O indications.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Guenther Hutzl <hutzl@linux.vnet.ibm.com>
Reviewed-by: Pierre Morel <pmorel@linux.vnet.ibm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This will better reflect its description i.e. "any needed setup..."
and not just do an "IPI request".
Signed-off-by: Noam Camus <noamc@ezchip.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
AZX_DCAPS_RIRB_PRE_DELAY is always tied with AZX_DCAPS_CTX_WORKAROUND,
which is Creative's XFi specific. So, we can replace it and reduce
one more bit free for DCAPS.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
ARC dwarf unwinder only supports CIE version == 1
The boot time dwarf sanitizer (part of binary lookup table constructor)
would simply bail if it saw CIE version == 3, rendering unwinder with a
NULL lookup table.
It seems libgcc linked with kernel does have such entries.
With fallback linear search removed, and a NULL binary lookup table,
unwinder fails to generate any stack trace.
So allow graceful ignoring of unsupported CIE entries.
This problem was initially seen in Alexey's setup (and not mine) as he
was using buildroot built toolchain (libgcc) which doesn't get built with
CFLAGS_FOR_TARGET="-gdwarf-2 which is my default
Fixes STAR 9000985048: "kernel unwinder broken with stock tools"
Fixes: 2e22502c08 ARC: dw2 unwind: Remove falllback linear search thru FDE entries
Reported-by Alexey Brodkin <abrodkin@synopsys.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
The fix which removed linear searching of dwarf (because binary lookup
data always exists) missed out on the fact that modules don't get the
binary lookup tables info. This caused unwinding out of modules to stop
working.
So add binary lookup header setup (equivalent of eh_frame_hdr setup) to
modules as well.
While at it, confine the header setup to within unwinder code,
reducing one API exposed out of unwinder code.
Fixes: 2e22502c08 ARC: dw2 unwind: Remove falllback linear search thru FDE entries
Cc: <stable@vger.kernel.org>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
HIGHMEM support bumped the default memory size for nsim platform to 1G.
Thus total memory ended at the very edge of start of peripherals address
space. With linux link base shifted, memory started bleeding into
peripheral space which caused early boot bad_page spew !
Fixes: 29e332261d ("ARC: mm: HIGHMEM: populate high memory from DT")
Reported-by: Anton Kolesov <akolesov@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
This patch adds the PM8916 regulator nodes found on MSM8916 platforms.
Signed-off-by: Andy Gross <agross@codeaurora.org>
Acked-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
Add support for the SMD and RPM devices found on MSM8916 platforms.
Signed-off-by: Andy Gross <agross@codeaurora.org>
Acked-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
This patch adds the nodes necessary to support the SMEM driver on MSM8916
platforms.
Signed-off-by: Andy Gross <agross@codeaurora.org>
Acked-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
2mA drive strength is not enough when we connect multiple i2c devices
on the bus with different pull up resistors.
This issue was detected when multiple i2c devices connected on the other side
of level shifters on Linaro sensor board. Maxing up to 16mA made i2c much stable.
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Andy Gross <andy.gross@linaro.org>
This patch fixes the i2c bus number aliasing so that it matches with the
schematics bus naming.
Without this patch the user might would get bus numbers depending on
the order the devices are probed.
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Andy Gross <andy.gross@linaro.org>
Currently the rates of the xo and sleep clocks are hard-coded in the
GCC driver, but this is a board layout description that actually should
be in the DT. Moving them into DT also allows us to insert the RPM
controlled clocks between the DT and GCC clocks.
Signed-off-by: Georgi Djakov <georgi.djakov@linaro.org>
Signed-off-by: Andy Gross <agross@codeaurora.org>
