10.03.2020 18:20, Thierry Reding пишет: > From: Joseph Lo <josephl@xxxxxxxxxx> > > 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@xxxxxxxxxx>. > > Signed-off-by: Joseph Lo <josephl@xxxxxxxxxx> > Signed-off-by: Thierry Reding <treding@xxxxxxxxxx> > --- > Changes in v5: > - major rework and cleanup > > drivers/memory/tegra/tegra210-emc.c | 1952 +++++++++++++++++++++------ > drivers/memory/tegra/tegra210-emc.h | 893 +++++++++++- > 2 files changed, 2390 insertions(+), 455 deletions(-) > > diff --git a/drivers/memory/tegra/tegra210-emc.c b/drivers/memory/tegra/tegra210-emc.c > index 80ea14d1e6ce..4ea8fb70a4fd 100644 > --- a/drivers/memory/tegra/tegra210-emc.c > +++ b/drivers/memory/tegra/tegra210-emc.c > @@ -1,6 +1,6 @@ > // SPDX-License-Identifier: GPL-2.0 > /* > - * Copyright (c) 2015-2019, NVIDIA CORPORATION. All rights reserved. > + * Copyright (c) 2015-2020, NVIDIA CORPORATION. All rights reserved. > */ Would be nice to avoid all the unnecessary changes, like the one above and then all the code's removals/reshuffling. Such that a new patch was a clean addition to a previous patch, instead of a re-write.
