[PATCH v4 0/8] Tegra20 External Memory Controller driver

[Dmitry Osipenko]

Hello,

Couple years ago the Tegra20 EMC driver was removed from the kernel
due to incompatible changes in the Tegra's clock driver. This patchset
introduces a modernized EMC driver. Currently the sole purpose of the
driver is to initialize DRAM frequency to maximum rate during of the
kernels boot-up. Later we may consider implementing dynamic memory
frequency scaling, utilizing functionality provided by this driver.

Changelog:

v4:
	- Fixed "bad of_node_put()" error which was revealed by enabling
	  some extra kernel debug config options.

	- The "emc-table" DT nodes are now parsed starting from the "emc"
	  node instead of the DT root.

	- Adjusted code comment in the "Turn EMC clock gate into divider"
	  patch as was suggested by Stephen Boyd to the v3.

v3:
	- Handle "nvidia,use-ram-code" DT property, its handling was missed
	  in the previous versions.

	- Honor "emc-tables" DT node naming which is explicitly specified
	  in the DT binding, also was missed in the previous versions.

	- Two new DT binding patches: one adds the EMC clock property,
	  other relocates the binding doc file to the appropriate directory.
	  One new patch that adds EMC clock property to the DTS file.

	- Addressed v2 review comments from Thierry Reding. Driver does not
	  preserve backwards compatibility with older device tree binding.

	- The PLL_M and PLL_P clocks are kept internal to the driver because
	  after some more considering I couldn't find a really good reason why
	  these clocks should be in the device tree.

	- Some minor cleanups and fixes in the drivers code.

v2:
	- Minor code cleanups like consistent use of writel_relaxed instead
	  of non-relaxed version, reworded error messages, etc.

	- Factored out use_pllm_ud bit checking into a standalone patch for
	  consistency.

Dmitry Osipenko (8):
  dt: bindings: tegra20-emc: Document interrupt property
  dt: bindings: tegra20-emc: Document clock property
  dt: bindings: Move tegra20-emc binding to memory-controllers directory
  ARM: dts: tegra20: Add interrupt entry to External Memory Controller
  ARM: dts: tegra20: Add clock entry to External Memory Controller
  clk: tegra20: Turn EMC clock gate into divider
  clk: tegra20: Check whether direct PLLM sourcing is turned off for EMC
  memory: tegra: Introduce Tegra20 EMC driver

 .../nvidia,tegra20-emc.txt                    |   4 +
 arch/arm/boot/dts/tegra20.dtsi                |   2 +
 drivers/clk/tegra/clk-tegra20.c               |  46 +-
 drivers/memory/tegra/Kconfig                  |  10 +
 drivers/memory/tegra/Makefile                 |   1 +
 drivers/memory/tegra/tegra20-emc.c            | 575 ++++++++++++++++++
 6 files changed, 628 insertions(+), 10 deletions(-)
 rename Documentation/devicetree/bindings/{arm/tegra => memory-controllers}/nvidia,tegra20-emc.txt (95%)
 create mode 100644 drivers/memory/tegra/tegra20-emc.c

-- 
2.18.0