diff options
| author | Joseph Lo <josephl@nvidia.com> | 2019-05-29 16:21:36 +0800 |
|---|---|---|
| committer | Thierry Reding <treding@nvidia.com> | 2020-06-22 13:54:57 +0200 |
| commit | 10de21148f7d28c9e918aaee7cede74a7d506e24 (patch) | |
| tree | 1fbcf76bc4a6a561c49e6c3bcd4ed1bbe2a86d98 /drivers/memory/tegra/Kconfig | |
| parent | 6cc8823ad3e85207dfb4c93f31dcdb05297d1b42 (diff) | |
| download | linux-next-10de21148f7d28c9e918aaee7cede74a7d506e24.tar.gz | |
memory: tegra: Add EMC scaling support code for Tegra210
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>
Diffstat (limited to 'drivers/memory/tegra/Kconfig')
| -rw-r--r-- | drivers/memory/tegra/Kconfig | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/drivers/memory/tegra/Kconfig b/drivers/memory/tegra/Kconfig index fbfbaada61a2..9f0a96bf9ccc 100644 --- a/drivers/memory/tegra/Kconfig +++ b/drivers/memory/tegra/Kconfig @@ -36,3 +36,17 @@ config TEGRA124_EMC Tegra124 chips. The EMC controls the external DRAM on the board. This driver is required to change memory timings / clock rate for external memory. + +config TEGRA210_EMC_TABLE + bool + depends on ARCH_TEGRA_210_SOC + +config TEGRA210_EMC + tristate "NVIDIA Tegra210 External Memory Controller driver" + depends on TEGRA_MC && ARCH_TEGRA_210_SOC + select TEGRA210_EMC_TABLE + help + This driver is for the External Memory Controller (EMC) found on + Tegra210 chips. The EMC controls the external DRAM on the board. + This driver is required to change memory timings / clock rate for + external memory. |