fix debugfs_simple_attr.cocci warning:
drivers/memory/tegra/tegra210-emc-core.c:1665:0-23: WARNING:tegra210_emc_debug_min_rate_fops
should be defined with DEFINE_DEBUGFS_ATTRIBUTE
Commit 6fc5f1adf5 ("memory: tegra210-emc: replace
DEFINE_SIMPLE_ATTRIBUTE with DEFINE_DEBUGFS_ATTRIBUTE") fixed the same
warning, but didn't fix all matches in this file at once.
Signed-off-by: Kai Song <songkai01@inspur.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Link: https://lore.kernel.org/r/20211005043514.9650-1-songkai01@inspur.com
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Fix the following coccicheck warning:
drivers/memory/tegra/tegra210-emc-core.c:1665:0-23:WARNING
tegra210_emc_debug_min_rate_fops should be defined with DEFINE_DEBUGFS_ATTRIBUTE
Signed-off-by: Jing Yangyang <jing.yangyang@zte.com.cn>
Link: https://lore.kernel.org/r/20210825063739.70260-1-deng.changcheng@zte.com.cn
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>
Multiple Tegra drivers need to retrieve Memory Controller and there is
duplication of the retrieval code among the drivers.
Add new devm_tegra_memory_controller_get() helper to remove the code's
duplication and to fix put_device() which was missed in the duplicated
code. Make EMC drivers to use the new helper.
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Link: https://lore.kernel.org/r/20201104164923.21238-29-digetx@gmail.com
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
The Tegra EMC scaling support code is not a clock provider, but merely a
clock consumer, and thus does not need to include
<linux/clk-provider.h>.
Fixes: 0bf368c5b2cf ("memory: tegra: Add EMC scaling support code for Tegra210")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Derated timings are used to ensure that the memory chips keep operating
correctly at high temperatures. This adds code to support polling of the
chip operating state when high temperatures are measured on the chip and
change the refresh mode accordingly. Under very high temperatures, the
driver will switch to the derated tables to ensure proper operation of
the memory chips.
Signed-off-by: Thierry Reding <treding@nvidia.com>
This patch includes the sequence for clock tuning and the dynamic
training mechanism for the clock above 800MHz.
And historically there have been different sequences to change the EMC
clock. The sequence to be used is specified in the EMC table.
However, for the currently supported upstreaming platform, only the most
recent sequence is used. So only support that in this patch.
Based on the work of Peter De Schrijver <pdeschrijver@nvidia.com>.
Signed-off-by: Joseph Lo <josephl@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
This is the initial patch for Tegra210 EMC frequency scaling. It has the
code to program various aspects of the EMC that are standardized, but it
does not yet include the specific programming sequence needed for clock
scaling.
The driver is designed to support LPDDR4 SDRAM. Devices that use LPDDR4
need to perform training of the RAM before it can be used. Firmware will
perform this training during early boot and pass a table of supported
frequencies to the kernel via device tree.
For the frequencies above 800 MHz, periodic retraining is needed to
compensate for changes in timing. This periodic training will have to be
performed until the frequency drops back to or below 800 MHz.
This driver provides helpers used during this runtime retraining that
will be used by the sequence specific code in a follow-up patch.
Based on work by Peter De Schrijver <pdeschrijver@nvidia.com>.
Signed-off-by: Joseph Lo <josephl@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>