[v7] : clk: Add common clock support for Mediatek MT8135 and MT8173

The following changes since commit 9eccca0843205f87c00404b663188b88eb248051:

  Linux 4.0-rc3 (2015-03-08 16:09:09 -0700)

are available in the git repository at:

  git://git.pengutronix.de/git/imx/linux-2.6.git tags/v4.0-clk-mediatek-v7

for you to fetch changes up to 147dc836b1206e8118509229594d82ff8ad3b99e:

  dt-bindings: ARM: Mediatek: Document devicetree bindings for clock/reset controllers (2015-03-16 06:31:37 +0100)

----------------------------------------------------------------
This patchset contains the initial common clock support for Mediatek SoCs.
Mediatek SoC's clock architecture comprises of various PLLs, dividers, muxes
and clock gates.

Sascha

Changes in v7:
- fix duplicate definition/declaration of mtk_register_reset_controller
- fix pd_reg offset of tvdpll
- make clk initialization arrays const

Changes in v6:
- rework PLL support, only a fraction of original size now
- Move binding docs to Documentation/devicetree/bindings/arm/mediatek since
  the units are not really clock specific (they contain reset controllers)

Changes in v5:
- Add reset controller support for pericfg/infracfg
- Use regmap for the gates
- remove now unnecessary spinlock for the gates
- Add PMIC wrapper support as of v3

Changes in v4:
- Support MT8173 platform.
- Re-ordered patchset. driver/clk/Makefile in 2nd patch.
- Extract the common part definition(mtk_gate/mtk_pll/mtk_mux) from
  clk-mt8135.c/clk-mt8173.c to clk-mtk.c.
- Refine code. Rmove unnessacary debug information and unsed defines,
  add prefix "mtk_" for static functions.
- Remove flag CLK_IGNORE_UNUSED and set flag CLK_SET_RATE_PARENT on
  gate/mux/fixed-factor.
- Use spin_lock_irqsave(&clk_ops_lock, flags) instead of mtk_clk_lock.
- Example above include a node for the clock controller itself, followed
  by the i2c controller example above.

Changes in v3:
- Rebase to 3.19-rc1.
- Refine code. Remove unneed functions, debug logs and comments, and fine tune
  error logs.

Changes in v2:
- Re-ordered patchset. Fold include/dt-bindings and DT document in 1st patch.

----------------------------------------------------------------
James Liao (3):
      clk: mediatek: Add initial common clock support for Mediatek SoCs.
      clk: mediatek: Add basic clocks for Mediatek MT8135.
      clk: mediatek: Add basic clocks for Mediatek MT8173.

Sascha Hauer (2):
      clk: mediatek: Add reset controller support
      dt-bindings: ARM: Mediatek: Document devicetree bindings for clock/reset controllers

 .../bindings/arm/mediatek/mediatek,apmixedsys.txt  |  23 +
 .../bindings/arm/mediatek/mediatek,infracfg.txt    |  30 +
 .../bindings/arm/mediatek/mediatek,pericfg.txt     |  30 +
 .../bindings/arm/mediatek/mediatek,topckgen.txt    |  23 +
 drivers/clk/Makefile                               |   1 +
 drivers/clk/mediatek/Makefile                      |   4 +
 drivers/clk/mediatek/clk-gate.c                    | 137 ++++
 drivers/clk/mediatek/clk-gate.h                    |  49 ++
 drivers/clk/mediatek/clk-mt8135.c                  | 640 ++++++++++++++++
 drivers/clk/mediatek/clk-mt8173.c                  | 826 +++++++++++++++++++++
 drivers/clk/mediatek/clk-mtk.c                     | 197 +++++
 drivers/clk/mediatek/clk-mtk.h                     | 165 ++++
 drivers/clk/mediatek/clk-pll.c                     | 325 ++++++++
 drivers/clk/mediatek/reset.c                       |  99 +++
 include/dt-bindings/clock/mt8135-clk.h             | 190 +++++
 include/dt-bindings/clock/mt8173-clk.h             | 231 ++++++
 .../dt-bindings/reset-controller/mt8135-resets.h   |  64 ++
 .../dt-bindings/reset-controller/mt8173-resets.h   |  63 ++
 18 files changed, 3097 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/arm/mediatek/mediatek,apmixedsys.txt
 create mode 100644 Documentation/devicetree/bindings/arm/mediatek/mediatek,infracfg.txt
 create mode 100644 Documentation/devicetree/bindings/arm/mediatek/mediatek,pericfg.txt
 create mode 100644 Documentation/devicetree/bindings/arm/mediatek/mediatek,topckgen.txt
 create mode 100644 drivers/clk/mediatek/Makefile
 create mode 100644 drivers/clk/mediatek/clk-gate.c
 create mode 100644 drivers/clk/mediatek/clk-gate.h
 create mode 100644 drivers/clk/mediatek/clk-mt8135.c
 create mode 100644 drivers/clk/mediatek/clk-mt8173.c
 create mode 100644 drivers/clk/mediatek/clk-mtk.c
 create mode 100644 drivers/clk/mediatek/clk-mtk.h
 create mode 100644 drivers/clk/mediatek/clk-pll.c
 create mode 100644 drivers/clk/mediatek/reset.c
 create mode 100644 include/dt-bindings/clock/mt8135-clk.h
 create mode 100644 include/dt-bindings/clock/mt8173-clk.h
 create mode 100644 include/dt-bindings/reset-controller/mt8135-resets.h
 create mode 100644 include/dt-bindings/reset-controller/mt8173-resets.h

Hello Sascha,

On Mon, Mar 16, 2015 at 06:55:09AM +0100, Sascha Hauer wrote:
> +static const char *axi_parents[] __initconst = {
> +	"clk26m",
> +	"syspll_d3",
> +	"syspll_d4",
> +	"syspll_d6",
> +	"univpll_d5",
> +	"univpll2_d2",
> +	"syspll_d3p5"
> +};
__initconst should only be used for const data, but this array isn't
const. Only the strings the pointer in this array point to are constant.

So you have to use either

	static const char *axi_parents[] __initdata = {

or

	static const char * const axi_parents[] __initconst = {

.

Best regards
Uwe

Hello Sascha,

On Tue, Mar 17, 2015 at 10:47:38AM +0100, Sascha Hauer wrote:
> On Mon, Mar 16, 2015 at 08:03:39AM +0100, Uwe Kleine-König wrote:
> > On Mon, Mar 16, 2015 at 06:55:09AM +0100, Sascha Hauer wrote:
> > > +static const char *axi_parents[] __initconst = {
> > > +	"clk26m",
> > > +	"syspll_d3",
> > > +	"syspll_d4",
> > > +	"syspll_d6",
> > > +	"univpll_d5",
> > > +	"univpll2_d2",
> > > +	"syspll_d3p5"
> > > +};
> > __initconst should only be used for const data, but this array isn't
> > const. Only the strings the pointer in this array point to are constant.
> 
> That may be true, but the way it's currently done compiles through
> without warnings with CONFIG_DEBUG_SECTION_MISMATCH enabled.
CONFIG_DEBUG_SECTION_MISMATCH doesn't catch this type of error.

> 
> > 
> > So you have to use either
> > 
> > 	static const char *axi_parents[] __initdata = {
> 
> This results in:
> 
> drivers/clk/mediatek/clk-mt8173.c:515:20: error: i2s3_b_ck_parents causes a section type conflict with infra_clks
>  static const char *i2s3_b_ck_parents[] __initdata = {
The compiler catches if a single section contains both modifiable and
constant data. The linker doesn't seem to check anything here. So you
have to do it consistently per compilation unit. (I'm not aware of any
problems if you do it consistently wrong in a compilation unit, but
better do it consistently right :-)
I'm sure getting it right isn't that hard, so IMHO this should be fixed
before your patch is applied.

> which can be avoided with static const char * const axi_parents[] __initdata
This should be __initconst (to do it consistently right).

> > or
> > 
> > 	static const char * const axi_parents[] __initconst = {
> 
> Which results in:
> 
> drivers/clk/mediatek/clk-mt8173.c:568:2: warning: initialization discards 'const' qualifier from pointer target type
>   MUX_GATE(TOP_HDCP_24M_SEL, "hdcp_24m_sel", hdcp_24m_parents, 0x00d0, 16, 2, 23),
> 
> With the following patch this can also be resolved. Until this is merged
> (or I have the OK from Mike to add this in front of this series) I
> prefer to keep it like it is at the moment.
I remember trying something like that some time ago, but without
success. I didn't modify clk-composite.c but still I would be surprised
if it were that easy.

(The result were commits like 4a043d79dc2d and 145047de9940.)

Best regards
Uwe