[PATCH 0/6] clk: tegra: add basic support for the DFLL clocksource
Paul Walmsley
pwalmsley at nvidia.com
Thu Dec 19 07:36:33 EST 2013
Hello,
This patch series adds support for the open-loop mode of the
Tegra DFLL root clock source. The DFLL can be used to provide an
energy-efficient and reliable clock signal for the Tegra114 fast
CPU cluster.
The core DFLL code requires some SoC-specific integration and
characterization data to function. For the time being, this has
been implemented via small shim drivers that are probed from DT
data and which pass per-SoC information to the DFLL core code.
Future patches will add board tuning data to the DT files.
This series isn't sufficient for the DFLL to be usable as the
fast CPU clock source. Further software support is needed to
switch the CPU cluster's clock from the default PLLX to the DFLL.
To test the basic functionality of the DFLL driver, something
like the following can be executed:
mount -t debugfs none /debug
cd /debug/tegra_dfll_fcpu/
echo 0 > enable
cat output_rate # ensure that it is 0
echo 1 > enable
cat output_rate # ensure that it is greater than 0
Future DFLL patches are planned to include reset controller
support, Tegra124 support, and closed-loop mode support.
- Paul
---
Danny Huang (1):
ARM: tegra: fuse: add functions to read speedo ID and process ID
Paul Walmsley (5):
ARM: tegra114: fuse: add DFLL FCPU minimum voltage override test function
clk: tegra: add library for the DFLL clocksource (open-loop mode)
ARM: DTS: tegra: add the DFLL IP block to the T114 SoC file
ARM: DTS: tegra: add DFLL integration to the Dalmore DTS file
clk: tegra: add Tegra114 FCPU DFLL clocksource platform driver
.../bindings/clock/nvidia,tegra114-dfll.txt | 59 +
arch/arm/boot/dts/tegra114-dalmore.dts | 4
arch/arm/boot/dts/tegra114.dtsi | 10
arch/arm/mach-tegra/fuse.c | 41 +
drivers/clk/Kconfig | 2
drivers/clk/tegra/Kconfig | 18
drivers/clk/tegra/Makefile | 11
drivers/clk/tegra/clk-dfll.c | 1229 ++++++++++++++++++++
drivers/clk/tegra/clk-dfll.h | 54 +
drivers/clk/tegra/clk-tegra114-dfll-fcpu.c | 169 +++
include/linux/tegra-soc.h | 6
11 files changed, 1602 insertions(+), 1 deletion(-)
create mode 100644 Documentation/devicetree/bindings/clock/nvidia,tegra114-dfll.txt
create mode 100644 drivers/clk/tegra/Kconfig
create mode 100644 drivers/clk/tegra/clk-dfll.c
create mode 100644 drivers/clk/tegra/clk-dfll.h
create mode 100644 drivers/clk/tegra/clk-tegra114-dfll-fcpu.c
text data bss dec hex filename
8010955 394200 352064 8757219 859fe3 vmlinux.next-20131218
8014811 395096 352064 8761971 85b273 vmlinux.next-20131218-dfll
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