lkml.org 
[lkml]   [2014]   [Jul]   [11]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Subject[PATCH 0/8] Tegra124 EMC (external memory controller) support
Date
Hi everyone,

this series adds support for the EMC (external memory controller) clock
in the Tegra124 system-on-chip. The series has been tested on Jetson TK1.

The first two patches remove the old "emc_mux" and "emc" clocks from the
clock tree and the device tree bindings. This is, of course, not backwards
compatible, but as these clocks have never been useful for anything
(apart from maybe reading the boot rate of the EMC clock). If this is still
not acceptable, the second patch can be dropped.

The second two patches add two clocks, PLL_M_UD and PLL_C_UD, that are
low jitter variants derived from PLL_M and PLL_C respectively. They are used
by some higher EMC clock rates as clock parents.

Patch 5 adds device tree binding documentation for the EMC clock node. It is
a whole separate block on the chip, so it does not go under CAR, as previous
clocks have done.

Patches 6 and 7 enable the EMC clock on Tegra124 and Jetson TK-1. The driver
is enabled always, but can only provide read-only access without EMC tables
that contain hardware characterization data for each operating point of the
clock.

Patch 8 adds the actual driver. The driver needs to write to both CAR and MC
registers in addition to EMC registers. These register accesses are either
shadowed or control a hardware state machine, so delegating them to other
drivers can be dangerous.

Patch 1 must go before patch 2 and patch 4 needs to go after patch 3
but otherwise there shouldn't be any compile-time dependencies.
Patch 7 has a DTC dependency on patch 3.

Also available from git in
git://github.com/cyndis/linux.git, branch emc-v1

Mikko Perttunen (8):
clk: tegra124: Remove old emc_mux and emc clocks
ARM: tegra: Remove TEGRA124_CLK_EMC from tegra124-car.h
ARM: tegra: Add PLL_M_UD and PLL_C_UD to tegra124-car binding header
clk: tegra124: Add PLL_M_UD and PLL_C_UD clocks
of: Add Tegra124 EMC bindings
ARM: tegra: Add EMC to Tegra124 device tree
ARM: tegra: Add EMC timings to Jetson TK1 device tree
clk: tegra: Add EMC clock driver

.../bindings/memory-controllers/tegra-emc.txt | 42 +
arch/arm/boot/dts/tegra124-jetson-tk1-emc.dtsi | 2323 ++++++++++++++++++++
arch/arm/boot/dts/tegra124-jetson-tk1.dts | 2 +
arch/arm/boot/dts/tegra124.dtsi | 6 +
drivers/clk/tegra/Makefile | 2 +-
drivers/clk/tegra/clk-emc.c | 1508 +++++++++++++
drivers/clk/tegra/clk-tegra124.c | 21 +-
include/dt-bindings/clock/tegra124-car.h | 8 +-
8 files changed, 3896 insertions(+), 16 deletions(-)
create mode 100644 Documentation/devicetree/bindings/memory-controllers/tegra-emc.txt
create mode 100644 arch/arm/boot/dts/tegra124-jetson-tk1-emc.dtsi
create mode 100644 drivers/clk/tegra/clk-emc.c

--
1.8.1.5



\
 
 \ /
  Last update: 2014-07-11 19:41    [W:0.317 / U:0.716 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site