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TI J7200 EVM has lp876441 pmic that is similar to tps65941. Add support
for same with existing driver with new compatible.
Signed-off-by: Gowtham Tammana <g-tammana@ti.com>
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Acked-by: Jaehoon Chung <jh80.chung@samsung.com>
Link: https://lore.kernel.org/r/20210714205300.17424-2-g-tammana@ti.com
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The K3 AM65x family of SoCs have the next generation of the PRU-ICSS
processor subsystem, commonly referred to as ICSSG. Each ICSSG processor
subsystem on AM65x SR1.0 contains two primary PRU cores and two new
auxiliary PRU cores called RTUs. The AM65x SR2.0 SoCs have a revised
ICSSG IP that is based off the subsequent IP revision used on J721E
SoCs. This IP instance has two new custom auxiliary PRU cores called
Transmit PRUs (Tx_PRUs) in addition to the existing PRUs and RTUs.
Each RTU and Tx_PRU cores have their own dedicated IRAM (smaller than
a PRU), Control and debug feature sets, but is different in terms of
sub-modules integrated around it and does not have the full capabilities
associated with a PRU core. The RTU core is typically used to aid a
PRU core in accelerating data transfers, while the Tx_PRU cores is
normally used to control the TX L2 FIFO if enabled in Ethernet
applications. Both can also be used to run independent applications.
The RTU and Tx_PRU cores though share the same Data RAMs as the PRU
cores, so the memories have to be partitioned carefully between different
applications. The new cores also support a new sub-module called Task
Manager to support two different context thread executions.
The driver currently supports the AM65xx SoC
Signed-off-by: Keerthy <j-keerthy@ti.com>
Signed-off-by: Suman Anna <s-anna@ti.com>
Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Link: https://lore.kernel.org/r/20210622063431.3151-3-lokeshvutla@ti.com
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The Programmable Real-Time Unit - Industrial Communication
Subsystem (PRU-ICSS) is present of various TI SoCs such as
AM335x or AM437x or the AM654x family. Each SoC can have
one or more PRUSS instances that may or may not be identical.
The PRUSS consists of dual 32-bit RISC cores called the
Programmable Real-Time Units (PRUs), some shared, data and
instruction memories, some internal peripheral modules, and
an interrupt controller. The programmable nature of the PRUs
provide flexibility to implement custom peripheral interfaces,
fast real-time responses, or specialized data handling.
Add support for pruss driver. Currently am654x family
is supported.
Signed-off-by: Keerthy <j-keerthy@ti.com>
Signed-off-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Link: https://lore.kernel.org/r/20210622063431.3151-2-lokeshvutla@ti.com
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scracth register
RTC second scratch register[32-bit]:
-zero byte hold boot count value
-first byte hold update available state
-second byte hold version
-third byte hold magic number
Signed-off-by: Gireesh Hiremath <Gireesh.Hiremath@in.bosch.com>
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Link: https://lore.kernel.org/r/20210611161350.2141-17-Gireesh.Hiremath@in.bosch.com
Gbp-Pq: Topic apertis/guardian
Gbp-Pq: Name am335x-guardian-software-update-available-status-is-store.patch
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update panel driver hx8238
fix build bug
Signed-off-by: Gireesh Hiremath <Gireesh.Hiremath@in.bosch.com>
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Link: https://lore.kernel.org/r/20210611161350.2141-15-Gireesh.Hiremath@in.bosch.com
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Function rtc_to_tm() is needed for FAT file system support even if we don't
have a real time clock. So move it from drivers/ to lib/.
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
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The ST-Ericsson DB8500 SoC contains a MUSB OTG controller which
supports both host and gadget mode. For some reason there is
nothing special about it - add a simple glue driver for Ux500
that literally just sets up MUSB together with a generic PHY.
There are no SoC-specific registers etc needed to make USB work.
The new Ux500 glue driver is only tested to work with DM_USB
and DM_USB_GADGET. Both host and gadget mode work fine on
the u8500 "stemmy" board that is already present in U-Boot.
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
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The AB8500 PMIC contains an USB PHY that needs to be set up in
device or host mode to make USB work properly. Add a simple driver
for the generic PHY uclass that allows enabling it.
The if (CONFIG_IS_ENABLED(USB_MUSB_HOST)) might be a bit strange.
The USB PHY must be configured in either host or device mode and
somehow the USB PHY driver must be made aware of the mode.
Actually, the MUSB driver used together with this PHY does not
support dynamic selection of host/device mode in U-Boot at the moment.
Therefore, one very simple approach that works fine is to select
the mode to configure at compile time. When the MUSB driver is
configured in host mode the PHY is configured in host mode, and
similarly when the MUSB driver is configured in device/gadget mode.
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
Reviewed-by: Jaehoon Chung <jh80.chung@samsung.com>
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All devices based on ST-Ericsson Ux500 use a PMIC similar to AB8500
(Analog Baseband). There is AB8500, AB8505, AB9540 and AB8540
although in practice only AB8500 and AB8505 are relevant since the
platforms with AB9540 and AB8540 were cancelled and never used in
production.
In general, the AB8500 PMIC uses I2C as control interface, where the
different register banks are represented as separate I2C devices.
However, in practice AB8500 is always connected to a special I2C bus
on the DB8500 SoC that is controlled by the power/reset/clock
management unit (PRCMU) firmware.
Add a simple driver that allows reading/writing registers of the
AB8500 PMIC. The driver directly accesses registers from the PRCMU
parent device (represented by syscon in U-Boot). Abstracting it
further (e.g. with the i2c uclass) would not provide any advantage
because the PRCMU I2C bus is always just connected to AB8500 and
vice-versa.
The ab8500.h header is mostly taken as-is from Linux (with some
minor adjustments) to allow using similar code in both Linux and
U-Boot.
Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
Acked-by: Jaehoon Chung <jh80.chung@samsung.com>
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Add PCIe driver for UniPhier SoCs. This PCIe controller is based on
Synopsys DesignWare Core IP.
This version doesn't apply common DW functions because supported
controller doesn't have unroll version of iATU.
Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
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Add PCIe PHY driver support for Pro5, LD20 and PXs3 SoCs.
Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
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Add reset control for PCIe controller on each SoC.
Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
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Add clock control for PCIe controller on each SoC.
Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
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Linux kernel binding is using atmel,24c01 compatible string. On the
other hand there is atmel,24c01a which is not listed in the kernel.
Add compatible string without "a" suffix to be compatible with Linux
kernel binding.
Signed-off-by: Marek Vasut <marek.vasut+renesas@gmail.com>
Cc: Heiko Schocher <hs@denx.de>
Cc: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Heiko Schocher <hs@denx.de>
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Simplify the code a bit by using dev_read_addr_ptr() instead of
dev_read_addr(). This avoids having to cast explicitly to the
struct nomadik_mtu_regs.
Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
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Nomadik GPIO is a fairly simple GPIO module used in the ST-Ericsson
Ux500 SoCs (and some older Nomadik SoCs). It uses registers where
each GPIO is represented as a single bit, plus "set" and "clear"
registers that allow updating the state without having to read the
existing state.
The driver implements support for it for use together with DM_GPIO
and the existing ste-dbx5x0.dtsi device tree.
Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
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The original U-Boot port for the ST-Ericsson U8500 SoC was dropped
in commit 68282f55b846 ("arm: Remove unused ST-Ericsson u8500 arch").
Most of the drivers related to the old port were removed, but the
db8500_gpio.c driver was forgotten for some reason. There is no way
to select it and it does not compile anymore because of missing
headers, so let's just remove it.
The new port for U8500 introduced in commit 689088f9dae8
("arm: Add support for ST-Ericsson U8500 SoC") fully embraces the
new Driver Model and device trees where possible, so this is
preparation to add a new, simplified GPIO driver based on DM_GPIO.
Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
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Aside from the usual fixes and updates one visible change is the
MMC update, which fixes some lingering bugs and gives a decent speed
increase on some boards (9->19 MB/s on H6, 21->43 MB/s on A64 eMMC).
I am keeping an watchful eye on bug reports here, to spot any correctness
regressions.
Another change is finally the enablement of the first USB host port on
many boards without micro-USB (data) sockets, like the Pine64 family.
That doubles the number of usable USB ports from 1 to 2 on those boards.
Some smaller fixes, 4GB DRAM support (on the H616) and a new board (ZeroPi)
conclude this first round of changes.
Compile-tested for all 157 sunxi boards, boot-tested on Pine H64,
Pine64-LTS, OrangePi Zero 2 and BananaPi M2 Berry.
Summary:
- DT update for H3/H5/H6
- Enable first USB port on boards without micro-USB
- ZeroPi board support
- 4GB DRAM support for H616 boards
- MMC fixes and speed improvement
- some fixes
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At the moment the Allwinner MMC driver parses the bus-width and
non-removable DT properties itself, in the probe() routine.
There is actually a generic function provided by the MMC framework doing
this job, also it parses more generic properties like broken-cd and
advanced transfer modes.
Drop our own code and call mmc_of_parse() instead, to get all new
features for free.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Jaehoon Chung <jh80.chung@samsung.com>
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To avoid the complexity of DMA operations (with chained descriptors), we
use repeated MMIO reads and writes to the SD_FIFO_REG, which allows us
to drain or fill the MMC data buffer FIFO very easily.
However those MMIO accesses are somewhat costly, so this limits our MMC
performance, to between 17 and 22 MB/s, but down to 9.5 MB/s on the H6
(partly due to the lower AHB1 frequency).
As it turns out we read the FIFO status register after *every* word we
read or write, which effectively doubles the number of MMIO accesses,
thus effectively more than halving our performance.
To avoid this overhead, we can make use of the FIFO level bits, which are
in the very same FIFO status registers.
So for a read request, we now can collect as many words as the FIFO
level originally indicated, and only then need to update the status
register.
We don't know for sure the size of the FIFO (and it seems to differ
across SoCs anyway), so writing is more fragile, which is why we still
use the old method for that. If we find a minimum FIFO size available on
all SoCs, we could use that, in a later optimisation.
This patch increases the eMMC read speed on a Pine64-LTS from about
22MB/s to 44 MB/s. SD card reads don't gain that much, but with 23 MB/s
we now reach the practical limit for 3.3V SD cards.
On the H6 we double our transfer speed, from 9.5 MB/s to 19.7 MB/s.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
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Newer SoCs have a self calibration feature, which avoids us writing hard
coded phase delay values into the controller.
Consolidate the code by avoiding unnecessary #ifdefs, and also enabling
the feature for all those newer SoCs.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
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Among the SoCs using the "new timing mode", only the A83T needs to
explicitly switch to that mode.
By just defining the symbol for that one odd A83T bit to 0 for any other
SoCs, we can always OR that in, and save the confusing nested #ifdefs.
Clean up the also confusing new_mode setting on the way.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Jaehoon Chung <jh80.chung@samsung.com>
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Most Allwinner SoCs which use the so called "new timing mode" in their
MMC controllers actually use the double-rate PLL6/PERIPH0 clock as their
parent input clock. This is interestingly enough compensated by a hidden
"by 2" post-divider in the mod clock, so the divider and actual output
rate stay the same.
Even though for the H6 and H616 (but only for them!) we use the doubled
input clock for the divider computation, we never accounted for the
implicit post-divider, so the clock was only half the speed on those SoCs.
This didn't really matter so far, as our slow MMIO routine limits the
transfer speed anyway, but we will fix this soon.
Clean up the code around that selection, to always use the normal PLL6
(PERIPH0(1x)) clock as an input. As the rate and divider are the same,
that makes no difference.
Explain the hardware differences in a comment.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
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When enabling PHYS_64BIT on 32-bit platforms, we get two warnings about
pointer casts in sunxi_mmc.c. Those are related to MMIO addresses, which
are always below 1GB on all Allwinner SoCs, so there is no problem with
anything having more than 32 bits.
Add the proper casts to make it compile cleanly.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Jaehoon Chung <jh80.chung@samsung.com>
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The delay and bus-width setup are slightly different across the
Allwinner SoC generations, and we covered this so far with some
preprocessor conditionals.
Use the more readable IS_ENABLE() instead.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Jaehoon Chung <jh80.chung@samsung.com>
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Recent Allwinner platforms (starting with the H3) only use the MUSB
controller for peripheral mode and use HCI for host mode. As a result,
extra steps need to be taken to properly route USB signals to one or
the other. More precisely, the following is required:
* Routing the pins to either HCI/MUSB (controlled by PHY);
* Enabling USB PHY passby in HCI mode (controlled by PMU).
The current code will enable passby for each PHY and reroute PHY0 to
MUSB, which is inconsistent and results in broken USB peripheral support.
Passby on PHY0 must only be enabled when we want to use HCI. Since
host/device mode detection is not available from the PHY code and
because U-Boot does not support changing the mode dynamically anyway,
we can just mux the controller to MUSB if it is enabled and mux it to
HCI otherwise.
This fixes USB peripheral support for platforms with PHY0 dual-route,
especially H3/H5 and V3s.
Signed-off-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
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Unfortunately the UART driver in current Linux for Armada 3700 expects
UART's parent clock to be XTAL and calculats baudrate divisor according
to XTAL clock. Therefore we must switch back to XTAL clock before
booting kernel.
Implement .remove method for this driver with DM_FLAG_OS_PREPARE flag
set.
If current baudrate is unsuitable for XTAL clock then we do not change
anything. This can only happen if the user either configured unsupported
settings or knows what they are doing and has kernel patches which allow
usage of non-XTAL parent clock.
Signed-off-by: Pali Rohár <pali@kernel.org>
Reviewed-by: Marek Behún <marek.behun@nic.cz>
Reviewed-by: Stefan Roese <sr@denx.de>
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Using TBG clock as parent clock for UART allows us using higher
baudrates than 230400.
Turris MOX with external FT232RL USB-UART works fine up to 3 MBaud
(which is maximum for this USB-UART controller), while EspressoBIN with
integrated pl2303 USB-UART also works fine up to 6 MBaud.
Slower baudrates with TBG as a parent clock can be achieved by
increasing TBG dividers and oversampling divider. When using the slowest
TBG clock, minimal working baudrate is 300.
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Marek Behún <marek.behun@nic.cz>
Reviewed-by: Stefan Roese <sr@denx.de>
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Setting DM_FLAG_PRE_RELOC for Armada 3720 clock drivers (TBG and
peripheral clocks) makes it possible for serial driver to retrieve clock
rates via clk API.
Signed-off-by: Marek Behún <marek.behun@nic.cz>
Reviewed-by: Stefan Roese <sr@denx.de>
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UART parent clock is by default the platform's xtal clock, which is
25 MHz.
The value defined in the driver, though, is 25.8048 MHz. This is a hack
for the suboptimal divisor calculation
Divisor = UART clock / (16 * baudrate)
which does not use rounding division, resulting in a suboptimal value
for divisor if the correct parent clock rate was used.
Change the code for divisor calculation to round to closest value, i.e.
Divisor = Round(UART clock / (16 * baudrate))
and change the parent clock rate value to that returned by
get_ref_clk().
This makes A3720 UART stable at standard UART baudrates between 1800 and
230400.
Signed-off-by: Pali Rohár <pali@kernel.org>
Reviewed-by: Marek Behún <marek.behun@nic.cz>
Reviewed-by: Stefan Roese <sr@denx.de>
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These boards have not been converted to CONFIG_DM_USB by the deadline
and is also missing conversion to CONFIG_DM. Remove them. As this is
the last of the SPEAr platforms, so remove the rest of the remaining
support as well.
Cc: Vipin Kumar <vipin.kumar@st.com>
Signed-off-by: Tom Rini <trini@konsulko.com>
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These boards have not been converted to CONFIG_DM_USB by the deadline
and is also missing conversion to CONFIG_DM. Remove them. As this is
also the last SPEAR3XX platform, remove that symbol as well.
Cc: Vipin Kumar <vipin.kumar@st.com>
Signed-off-by: Tom Rini <trini@konsulko.com>
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These boards have not been converted to CONFIG_DM_USB by the deadline
and is also missing conversion to CONFIG_DM. Remove them.
Cc: Vipin Kumar <vipin.kumar@st.com>
Signed-off-by: Tom Rini <trini@konsulko.com>
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These boards have not been converted to CONFIG_DM_USB by the deadline
and is also missing conversion to CONFIG_DM. Remove them.
Cc: Vipin Kumar <vipin.kumar@st.com>
Signed-off-by: Tom Rini <trini@konsulko.com>
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These boards have not been converted to CONFIG_DM_USB by the deadline
and is also missing conversion to CONFIG_DM. Remove it.
This is also the last PL010_SERIAL using board, so remove those
references.
Cc: Sergey Kostanbaev <sergey.kostanbaev@fairwaves.ru>
Signed-off-by: Tom Rini <trini@konsulko.com>
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This board has not been converted to CONFIG_DM_PCI by the deadline and is
also missing conversion to CONFIG_DM. Remove it. As this is the last
ARCH_T4160 platform, remove that support as well.
Signed-off-by: Tom Rini <trini@konsulko.com>
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This board has not been converted to CONFIG_DM_PCI by the deadline and is
also missing conversion to CONFIG_DM. Remove it. This is also the last
of the ARCH_MPC8641/MPC8610 platforms, so remove that support as well.
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Priyanka Jain <priyanka.jain@nxp.com>
Signed-off-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
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These boards have not been converted to CONFIG_DM_PCI by the deadline and is
also missing conversion to CONFIG_DM. Remove them. As this includes
the last ARCH_MPC8572 platform, remove that as well.
Cc: Peter Tyser <ptyser@xes-inc.com>
Signed-off-by: Tom Rini <trini@konsulko.com>
Acked-by: Peter Tyser <ptyser@xes-inc.com>
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These boards have not been converted to CONFIG_DM_PCI by the deadline
and is also missing conversion to CONFIG_DM. Remove them. As this is
the only ARCH_T1023 platform left, remove that support as well.
Cc: Priyanka Jain <priyanka.jain@nxp.com>
Signed-off-by: Tom Rini <trini@konsulko.com>
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These boards have not been converted to CONFIG_DM_PCI by the deadline and is
also missing conversion to CONFIG_DM. Remove them. As this is the only
ARCH_MPC8555 platform left, remove that support as well.
Cc: Priyanka Jain <priyanka.jain@nxp.com>
Signed-off-by: Tom Rini <trini@konsulko.com>
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This board has not been converted to CONFIG_DM_PCI by the deadline and is
also missing conversion to CONFIG_DM. Remove it. As this is the only
MPC8541 target left, remove that architecture support as well.
Cc: Priyanka Jain <priyanka.jain@nxp.com>
Signed-off-by: Tom Rini <trini@konsulko.com>
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These boards have not been converted to CONFIG_DM_PCI by the deadline
and is also missing conversion to CONFIG_DM. Remove them.
Cc: Reinhard Arlt <reinhard.arlt@esd-electronics.com>
Signed-off-by: Tom Rini <trini@konsulko.com>
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These board has not been converted to CONFIG_DM_PCI by the deadline.
Remove them. As this is the last of the mcf547x_8x family of boards,
remove that support as well.
Cc: TsiChung Liew <Tsi-Chung.Liew@nxp.com>
Signed-off-by: Tom Rini <trini@konsulko.com>
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various minor sandbox improvements
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- Update CI to use gcc-11.1 and clang-11 to build everything. This
requires a few fixes to the code that these newer compilers have
exposed.
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With gcc-11 we get a multiple errors here as the declarations for
mscc_pinctrl_ops and mscc_gpio_ops are missing an extern.
CC: Gregory CLEMENT <gregory.clement@bootlin.com>
Cc: Lars Povlsen <lars.povlsen@microchip.com>
Cc: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Reviewed-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
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With gcc-11 we see:
drivers/ddr/marvell/a38x/ddr3_debug.c:672:47: error: argument 2 of type 'u32[5]' {aka 'unsigned int[5]'} with mismatched bound [-Werror=array-parameter=]
672 | int ddr3_tip_read_adll_value(u32 dev_num, u32 pup_values[MAX_INTERFACE_NUM * MAX_BUS_NUM],
| ~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from drivers/ddr/marvell/a38x/ddr3_training_ip_engine.h:10,
from drivers/ddr/marvell/a38x/ddr3_init.h:17,
from drivers/ddr/marvell/a38x/ddr3_debug.c:6:
drivers/ddr/marvell/a38x/ddr3_training_ip_flow.h:116:47: note: previously declared as 'u32[]' {aka 'unsigned int[]'}
And similar warnings. Correct these by updating the prototype. Remove
the prototype for ddr3_tip_read_pup_value as it is unused.
Signed-off-by: Tom Rini <trini@konsulko.com>
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https://source.denx.de/u-boot/custodians/u-boot-atmel
First set of u-boot-atmel fixes for 2021.10 cycle:
This small fixes set is dedicated to fixing the onewire subsystem for
the at91 boards which was broken since 2020.04.
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- mpc8379erdb DM_USB, DM_PCI and DM_ETH support.
- Drop PCI support from the integrator family of boards
- Add synquacer support
- Assorted lpc32xx updates and improvements
- snapdragon (and related) fixes, Broadcom iproc update
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At the moment, the U-Boot serial_msm driver does not initialize the
UART_DM_DMEN register with the required value. Usually this does not
cause any problems, because there is Qualcomm's LK bootloader running
before U-Boot which initializes the register with the correct value.
It's important that this register is initialized correctly, because
the U-Boot driver does not make use of the BAM/DMA or single character
mode functionality of the UART controller. A different bootloader
before U-Boot might initialize the register differently.
For example, on DragonBoard 410c U-Boot can also be installed to the
"aboot" partition (replacing LK entirely). In this case U-Boot is
loaded directly by SBL, which seems to use the single-character mode
for some reason. In single character mode there is always just one
char in the FIFO, instead of the 4 characters expected by
msm_serial_fetch(). It also causes issues with "earlycon" later in
the Linux kernel, which tries to output 4 chars at once,
but only the first char will be written.
This causes early UART log in Linux to be corrupted like this:
[ 00ano:ameoi .Q1B[ 00ac _idaM00080oo'ahani-lcle._20). 15NdNii 5 SPMSJ20:U2
[ 00rkoolmsamel
[ 00Fw ]elamletopsioble
[ 00ore
instead of
[ 0.000000] Booting Linux on physical CPU 0x0000000000 [0x410fd030]
[ 0.000000] Machine model: Qualcomm Technologies, Inc. APQ 8016 SBC
[ 0.000000] earlycon: msm_serial_dm0 at MMIO 0x00000000078b0000 (options '')
[ 0.000000] printk: bootconsole [msm_serial_dm0] enabled
Make sure to initialize UART_DM_DMEN correctly to fix this issue
when loading U-Boot directly after SBL (instead of through LK).
There is no functional difference when loading U-Boot through LK
since LK also initializes UART_DM_DMEN to 0x0. [1]
[1]: https://git.linaro.org/landing-teams/working/qualcomm/lk.git/tree/platform/msm_shared/uart_dm.c?h=dragonboard410c-LA.BR.1.2.7-03810-8x16.0-linaro3#n203
Cc: Ramon Fried <rfried.dev@gmail.com>
Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
Reviewed-by: Ramon Fried <rfried.dev@gmail.com>
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