Memory chip select is swapped when we read mode register, correct it.
We didn't have devices that use a single LPDDR chip and both chips are
always identical, hence this change is just a minor improvement.
Fixes: 131dd9a436 ("memory: tegra20-emc: Support matching timings by LPDDR2 configuration")
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Link: https://lore.kernel.org/r/20211222043215.28237-2-digetx@gmail.com
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Tegra20 EMC driver uses simple devfreq governor. Add simple devfreq
governor to the list of the Tegra20 EMC driver module softdeps to allow
userspace initramfs tools like dracut to automatically pull the devfreq
module into ramfs image together with the EMC module.
Reported-by: Nicolas Chauvet <kwizart@gmail.com>
Suggested-by: Nicolas Chauvet <kwizart@gmail.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Link: https://lore.kernel.org/r/20211019231524.888-1-digetx@gmail.com
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
ASUS Transformer TF101 doesn't provide RAM code and in this case memory
timings should be selected based on identity information read out from
SDRAM chip. Support matching timings by LPDDR2 configuration.
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Link: https://lore.kernel.org/r/20211006224659.21434-10-digetx@gmail.com
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
The debugfs_create_dir() function does not return NULL, it returns error
pointers. But in normal situations like this where the caller is not
dereferencing "emc->debugfs.root" then we are not supposed to check the
return. So instead of fixing these checks, we should delete them.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/YMCQDTSyG8UuQoh0@mwanda
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Use common devm_tegra_core_dev_init_opp_table() helper for the OPP table
initialization.
Tested-by: Paul Fertser <fercerpav@gmail.com> # PAZ00 T20
Tested-by: Nicolas Chauvet <kwizart@gmail.com> # PAZ00 T20
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Probing of EMC drivers may be deferred and in this case we get duplicated
info messages during kernel boot. Use dev_info_once() helper to silence
the duplicated messages.
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Link: https://lore.kernel.org/r/20210330230445.26619-7-digetx@gmail.com
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
There is no point calling dev_pm_opp_set_clkname() with the "name"
parameter set to NULL, this is already done by the OPP core at setup
time and should work as it is.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Tested-by: Dmitry Osipenko <digetx@gmail.com>
Link: https://lore.kernel.org/r/0f22cc1791d8b88c50a9790c2dc19455b34ec7b0.1611742564.git.viresh.kumar@linaro.org
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Support hardware versioning, which is now required for Tegra20 EMC OPP.
Clean up OPP table initialization by using a error code returned by OPP
API for judging about the OPP table presence in a device-tree and remove
OPP regulator initialization because we're now going to use power domain
instead of a raw regulator. This puts Tegra20 EMC OPP preparation on par
with the Tegra30/124 EMC drivers.
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Link: https://lore.kernel.org/r/20201203192439.16177-3-digetx@gmail.com
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Add devfreq support to the Tegra20 EMC driver. Memory utilization
statistics will be periodically polled from the memory controller and
appropriate minimum clock rate will be selected by the devfreq governor.
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Link: https://lore.kernel.org/r/20201111011456.7875-5-digetx@gmail.com
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Remove IRQ number from error message since it doesn't add any useful
information, especially because this number is virtual.
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Link: https://lore.kernel.org/r/20201111011456.7875-6-digetx@gmail.com
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Factor out clk initialization and make it resource-managed. This makes
easier to follow code and will help to make further changes cleaner.
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Link: https://lore.kernel.org/r/20201111011456.7875-4-digetx@gmail.com
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
The dev_pm_opp_get_opp_table() shouldn't be used by drivers, use
dev_pm_opp_set_clkname() instead.
Suggested-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Link: https://lore.kernel.org/r/20201111011456.7875-3-digetx@gmail.com
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Now Internal and External Memory Controllers are memory interconnection
providers. This allows us to use interconnect API for tuning of memory
configuration. EMC driver now supports OPPs and DVFS.
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Link: https://lore.kernel.org/r/20201104164923.21238-36-digetx@gmail.com
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
EMC driver will become mandatory after turning it into interconnect
provider because interconnect users, like display controller driver, will
fail to probe using newer device-trees that have interconnect properties.
Thus make EMC driver to probe even if timings are missing in device-tree.
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Link: https://lore.kernel.org/r/20201104164923.21238-35-digetx@gmail.com
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Add modularization support to the Tegra20 EMC driver, which now can be
compiled as a loadable kernel module.
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Link: https://lore.kernel.org/r/20201104164923.21238-34-digetx@gmail.com
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
The platform_get_irq() prints error message telling that interrupt is
missing, hence there is no need to duplicated that message in the drivers.
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Link: https://lore.kernel.org/r/20201104164923.21238-31-digetx@gmail.com
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Use devm_platform_ioremap_resource() helper which makes code a bit
cleaner.
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Link: https://lore.kernel.org/r/20201104164923.21238-30-digetx@gmail.com
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
The memory clock-rate change could be running on a non-boot CPU, while the
boot CPU handles the EMC interrupt. This introduces an unnecessary latency
since boot CPU should handle the interrupt and then notify the sibling CPU
about clock-rate change completion. In some rare cases boot CPU could be
in uninterruptible state for a significant time (like in a case of KASAN +
NFS root), it could get to the point that completion timeouts before boot
CPU gets a chance to handle interrupt. The solution is to get rid of the
completion and replace it with interrupt-status polling.
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Replace the symbolic permissions with octals in order to make them
readable.
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Correctly set clk rate-range if number of available timings is zero.
This fixes noisy "invalid range [4294967295, 0]" error messages during
boot.
Fixes: 8209eefa3d ("memory: tegra: Implement EMC debugfs interface on Tegra20")
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
A common debugfs interface is already available on Tegra124, Tegra186
and Tegra194. Implement the same interface on Tegra20 to enable testing
of the EMC frequency scaling code using a unified interface.
Signed-off-by: Thierry Reding <treding@nvidia.com>
Contrary to its wait_for_completion_timeout_interruptible() sibling, the
wait_for_completion_timeout() function does not return an error.
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Turned out that it could take over a millisecond under some circumstances,
like running on a very low CPU/memory frequency. TRM says that handshake
happens when there is a "safe" moment, but not explains exactly what that
moment is. Apparently at least memory should be idling and thus the low
frequency should be a reasonable cause for a longer handshake delay.
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
During boot print how many memory timings got the driver and what's the
RAM code. This is a very useful information when something is wrong with
boards memory timing.
Suggested-by: Marc Dietrich <marvin24@gmx.de>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
The driver expects certain debug features to be disabled in order to
work properly. Let's disable them explicitly for consistency and to not
rely on a boot state.
Acked-by: Peter De Schrijver <pdeschrijver@nvidia.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
The register polling code was gone, but the included header change was
missed. Fix it up for consistency.
Acked-by: Peter De Schrijver <pdeschrijver@nvidia.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Now Tegra20 and Tegra30 EMC drivers should provide clock-rounding
functionality using the new Tegra clock driver API.
Acked-by: Peter De Schrijver <pdeschrijver@nvidia.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
The memory frequency scaling will be managed by tegra20-devfreq driver
and PM QoS once all the prerequisite patches will get upstreamed.
The parent clock is now managed by the clock driver and we also should
assume that PLLM rate can't be changed on some devices (Galaxy Tab 10.1
for example). Altogether there is no point in touching of clock's rate
from the EMC driver.
Acked-by: Peter De Schrijver <pdeschrijver@nvidia.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Introduce driver for the External Memory Controller (EMC) found on Tegra20
chips, which controls the external DRAM on the board. The purpose of this
driver is to program memory timing for external memory on the EMC clock
rate change.
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Peter De Schrijver <pdeschrijver@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Dmitry Osipenko