[PATCH v4 00/23] soc: renesas: Add R-Car RST driver for obtaining mode pin state
Geert Uytterhoeven
geert+renesas at glider.be
Fri Oct 21 06:17:14 PDT 2016
Hi Philipp, Mike, Stephen, Simon, Magnus,
(see questions *** below!)
Currently the R-Car Clock Pulse Generator (CPG) drivers obtains the
state of the mode pins either by a call from the platform code, or
directly by using a hardcoded register access. This is a bit messy, and
creates a dependency between driver and platform code.
This patch series converts the various Renesas R-Car clock drivers
and support code from reading the mode pin states using a hardcoded
register access to using a new minimalistic R-Car RST driver.
All R-Car clock drivers will rely on the presence in DT of a device node
for the RST module. Backwards compatibility with old DTBs is retained
only for R-Car Gen2, which has fallback code using its own private copy
of rcar_gen2_read_mode_pins().
After this, there is still one remaining user of
rcar_gen2_read_mode_pins() left in platform code. A patch series to
remove that user has already been posted, though ("[PATCH/RFT 0/4] ARM:
shmobile: R-Car Gen2: Allow booting secondary CPU cores in debug mode").
Since v3, the other user has been removed in commit 9f5ce39ddb8f68b3
("ARM: shmobile: rcar-gen2: Obtain extal frequency from DT").
This series consists of 5 parts:
A. Patches 1 and 2 add DT bindings and driver code for the R-Car RST
driver,
B. Patches 3-11 add device nodes for the RST modules to the R-Car DTS
files,
C. Patches 12-17 convert the clock drivers to call into the new R-Car
RST driver,
D. Patches 18-20 remove passing mode pin state to the clock drivers
from the platform code,
E. Patches 21-23 remove dead code from the clock drivers.
As is usually the case with moving functionality from platform code to
DT, there are lots of hard dependencies:
- The DT updates in Part B can be merged as soon as the DT bindings in
Part A have been approved,
- The clock driver updates in Part C depend functionally on the driver
code in Part A, and on the DT updates in Part B,
- The board code cleanups in Part D depend on the clock driver updates
in Part C,
- The block driver cleanups in part E depend on the board code
cleanups in part D.
Hence to maintain the required lockstep between SoC driver, clock
drivers, shmobile platform code, and shmobile DT, I propose to queue up
all patches in a single branch against v4.9-rc1, and send pull requests
to both Mike/Stephen (clock) and Simon (rest).
***
- Philip: While this is a driver for a reset-controller, currently it
doesn't provide any reset-controller functionality. Hence I added it
to drivers/soc/renesas/. Is that OK for you?
- Mike/Stephen/Simon/Magnus: Are you OK with the suggested merge
approach above?
This series has evolved over time, cfr.:
- "[PATCH/RFC v3 00/22] soc: renesas: Add R-Car RST driver for
obtaining mode pin state"
(http://www.spinics.net/lists/linux-renesas-soc/msg04289.html),
- "[PATCH/RFC 00/11] ARM: shmobile: Let CPG use syscon for MD pin
values" (http://www.spinics.net/lists/linux-clk/msg01478.html),
- "[PATCH 00/10] arm64: renesas: Obtain MD pin values using
syscon/regmap".
(http://www.spinics.net/lists/linux-sh/msg44757.html)
Changes compared to v3:
- Add Acked-by, Reviewed-by,
- Add support for R-Car V2H,
- Add support for RZ/G1M and RZ/G1E,
- Remove the initcall and the rcar_rst_base check in rcar_rst_init(),
as rcar_rst_init() is only used as a support function for
rcar_rst_read_mode_pins(),
- Refer to rcar_rst_gen2 for R-Car Gen3 instead of providing an
identical copy,
- Use our own private copy of rcar_gen2_read_mode_pins() instead of
the one in the R-Car Gen2 platform code, as the latter is planned to
be removed,
- Rebase on top of "ARM: shmobile: rcar-gen2: Obtain extal frequency
from DT",
Changes compared to v2:
- Use "renesas,<soctype>-rst" instead of "renesas,rst-<soctype>",
- Drop "syscon" compatible value and "renesas,modemr" property, use a
real driver instead,
- Add support for R-Car M1A, H1, and M3-W.
Changes compared to v1:
- Add support for R-Car H3.
This patch series is against v4.9-rc1. When applying it to
renesas-devel-20161021-v4.9-rc1, there's a small conflict in
drivers/soc/renesas/Makefile (both sides added lines).
For your convenience, this series is also available in the
topic/rcar-rst-v4 branch of my renesas-drivers git repository at
git://git.kernel.org/pub/scm/linux/kernel/git/geert/renesas-drivers.git
This has been tested on r8a7778/bockw, r8a7779/marzen, r8a7791/koelsch,
r8a7795/salvator-x, and r8a7796/salvator-x.
Thanks!
Geert Uytterhoeven (23):
reset: Add renesas,rst DT bindings
soc: renesas: Add R-Car RST driver
ARM: dts: r8a7778: Add device node for RESET/WDT module
ARM: dts: r8a7779: Add device node for RESET/WDT module
ARM: dts: r8a7790: Add device node for RST module
ARM: dts: r8a7791: Add device node for RST module
ARM: dts: r8a7792: Add device node for RST module
ARM: dts: r8a7793: Add device node for RST module
ARM: dts: r8a7794: Add device node for RST module
arm64: renesas: r8a7795 dtsi: Add device node for RST module
arm64: renesas: r8a7796 dtsi: Add device node for RST module
clk: renesas: r8a7778: Obtain mode pin values using R-Car RST driver
clk: renesas: r8a7779: Obtain mode pin values from R-Car RST driver
clk: renesas: rcar-gen2: Obtain mode pin values using RST driver
clk: renesas: r8a7795: Obtain mode pin values from R-Car RST driver
clk: renesas: r8a7796: Obtain mode pin values from R-Car RST driver
clk: renesas: rcar-gen3-cpg: Remove obsolete
rcar_gen3_read_mode_pins()
ARM: shmobile: r8a7778: Stop passing mode pins state to clock driver
ARM: shmobile: r8a7779: Stop passing mode pins state to clock driver
ARM: shmobile: rcar-gen2: Stop passing mode pins state to clock driver
clk: renesas: r8a7778: Remove obsolete r8a7778_clocks_init()
clk: renesas: r8a7779: Remove obsolete r8a7779_clocks_init()
clk: renesas: rcar-gen2: Remove obsolete rcar_gen2_clocks_init()
.../devicetree/bindings/reset/renesas,rst.txt | 37 +++++++++
arch/arm/boot/dts/r8a7778.dtsi | 5 ++
arch/arm/boot/dts/r8a7779.dtsi | 5 ++
arch/arm/boot/dts/r8a7790.dtsi | 5 ++
arch/arm/boot/dts/r8a7791.dtsi | 5 ++
arch/arm/boot/dts/r8a7792.dtsi | 5 ++
arch/arm/boot/dts/r8a7793.dtsi | 5 ++
arch/arm/boot/dts/r8a7794.dtsi | 5 ++
arch/arm/mach-shmobile/setup-r8a7778.c | 15 ----
arch/arm/mach-shmobile/setup-r8a7779.c | 27 -------
arch/arm/mach-shmobile/setup-rcar-gen2.c | 5 +-
arch/arm64/boot/dts/renesas/r8a7795.dtsi | 5 ++
arch/arm64/boot/dts/renesas/r8a7796.dtsi | 5 ++
drivers/clk/renesas/clk-r8a7778.c | 26 +++---
drivers/clk/renesas/clk-r8a7779.c | 18 ++---
drivers/clk/renesas/clk-rcar-gen2.c | 32 ++++++--
drivers/clk/renesas/r8a7795-cpg-mssr.c | 8 +-
drivers/clk/renesas/r8a7796-cpg-mssr.c | 8 +-
drivers/clk/renesas/rcar-gen3-cpg.c | 17 ----
drivers/clk/renesas/rcar-gen3-cpg.h | 1 -
drivers/soc/renesas/Makefile | 5 ++
drivers/soc/renesas/rcar-rst.c | 92 ++++++++++++++++++++++
include/linux/clk/renesas.h | 4 -
include/linux/soc/renesas/rcar-rst.h | 6 ++
24 files changed, 246 insertions(+), 100 deletions(-)
create mode 100644 Documentation/devicetree/bindings/reset/renesas,rst.txt
create mode 100644 drivers/soc/renesas/rcar-rst.c
create mode 100644 include/linux/soc/renesas/rcar-rst.h
--
1.9.1
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert at linux-m68k.org
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
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