So the boards which has COMMON_CLK enabled don't have to
invoke this in its board specific file.
Signed-off-by: NKevin Hao <haokexin@gmail.com>
Acked-by: NScott Wood <scottwood@freescale.com>
Acked-by: NMichael Turquette <mturquette@linaro.org>
Signed-off-by: NMichael Turquette <mturquette@linaro.org>

improve the common clock support code for MPC512x

- expand the CCM register set declaration with MPC5125 related registers
  (which reside in the previously "reserved" area)
- tell the MPC5121, MPC5123, and MPC5125 SoC variants apart, and derive
  the availability of components and their clocks from the detected SoC
  (MBX, AXE, VIU, SPDIF, PATA, SATA, PCI, second FEC, second SDHC,
  number of PSC components, type of NAND flash controller,
  interpretation of the CPMF bitfield, PSC/CAN mux0 stage input clocks,
  output clocks on SoC pins)
- add backwards compatibility (allow operation against a device tree
  which lacks clock related specs) for MPC5125 FECs, too

telling SoC variants apart and adjusting the clock tree's generation
occurs at runtime, a common generic binary supports all of the chips

the MPC5125 approach to the NFC clock (one register with two counters
for the high and low periods of the clock) is not implemented, as there
are no users and there is no common implementation which supports this
kind of clock -- the new implementation would be unused and could not
get verified, so it shall wait until there is demand
Signed-off-by: NGerhard Sittig <gsi@denx.de>
Acked-by: NMike Turquette <mturquette@linaro.org>
Signed-off-by: NAnatolij Gustschin <agust@denx.de>

the SDHC clock is derived from CSB with a fractional divider which can
address "quarters"; the implementation multiplies CSB by 4 and divides
it by the (integer) divider value

a bug in the clock domain synchronisation requires that only even
divider values get setup; we achieve this by
- multiplying CSB by 2 only instead of 4
- registering with CCF the divider's bit field without bit0
- the divider's lowest bit remains clear as this is the reset value
  and later operations won't touch it

this change keeps fully utilizing common clock primitives (needs no
additional support logic, and avoids an excessive divider table) and
satisfies the hardware's constraint of only supporting even divider
values
Signed-off-by: NGerhard Sittig <gsi@denx.de>
Acked-by: NMike Turquette <mturquette@linaro.org>
Signed-off-by: NAnatolij Gustschin <agust@denx.de>

adjust (expand on or move) a few comments,
add markers for easier navigation around helpers
Signed-off-by: NGerhard Sittig <gsi@denx.de>
Acked-by: NMike Turquette <mturquette@linaro.org>
Signed-off-by: NAnatolij Gustschin <agust@denx.de>

this change removes workarounds which have become obsolete after
migration to common clock support has completed
- remove clkdev registration calls (compatibility clock item aliases)
  after all peripheral drivers were adjusted for device tree based
  clock lookup
- remove pre-enable workarounds after all peripheral drivers were
  adjusted to acquire their respective clock items

workarounds for these clock items get removed:  FEC (ethernet), I2C,
PSC (UART, SPI), PSC FIFO, USB, NFC (NAND flash), VIU (video capture),
BDLC (CAN), CAN MCLK, DIU (video output)

these clkdev registered names won't be provided any longer by the
MPC512x platform's clock driver:  "psc%d_mclk", "mscan%d_mclk",
"usb%d_clk", "nfc_clk", "viu_clk", "sys_clk", "ref_clk"

the pre-enable workaround for PCI remains, but depends on the presence
of PCI related device tree nodes (disables the PCI clock in the absence
of PCI nodes, keeps the PCI clock enabled in the presence of nodes) --
moving clock acquisition into the peripheral driver isn't possible for
PCI because its initialization takes place before the platform clock
driver gets initialized, thus the clock provider isn't available then

Cc: Mike Turquette <mturquette@linaro.org>
Cc: Anatolij Gustschin <agust@denx.de>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: NGerhard Sittig <gsi@denx.de>
Signed-off-by: NAnatolij Gustschin <agust@denx.de>

extend the recently added COMMON_CLK platform support for MPC512x such
that it works with incomplete device tree data which lacks clock specs

Cc: Mike Turquette <mturquette@linaro.org>
Cc: Anatolij Gustschin <agust@denx.de>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: NGerhard Sittig <gsi@denx.de>
[agust@denx.de: moved node macro definitions out of the function body]
Signed-off-by: NAnatolij Gustschin <agust@denx.de>

this change implements a clock driver for the MPC512x PowerPC platform
which follows the COMMON_CLK approach and uses common clock drivers
shared with other platforms

this driver implements the publicly announced set of clocks (those
listed in the dt-bindings header file), as well as generates additional
'struct clk' items where the SoC hardware cannot easily get mapped to
the common primitives (shared code) of the clock API, or requires
"intermediate clock nodes" to represent clocks that have both gates and
dividers

the previous PPC_CLOCK implementation is kept in place and remains
active for the moment, the newly introduced CCF clock driver will
receive additional support for backwards compatibility in a subsequent
patch before it gets enabled and will replace the PPC_CLOCK approach

some of the clock items get pre-enabled in the clock driver to not have
them automatically disabled by the underlying clock subsystem because of
their being unused -- this approach is desirable because
- some of the clocks are useful to have for diagnostics and information
  despite their not getting claimed by any drivers (CPU, internal and
  external RAM, internal busses, boot media)
- some of the clocks aren't claimed by their peripheral drivers yet,
  either because of missing driver support or because device tree specs
  aren't available yet (but the workarounds will get removed as the
  drivers get adjusted and the device tree provides the clock specs)

clkdev registration provides "alias names" for few clock items
- to not break those peripheral drivers which encode their component
  index into the name that is used for clock lookup (UART, SPI, USB)
- to not break those drivers which use names for the clock lookup which
  were encoded in the previous PPC_CLOCK implementation (NFC, VIU, CAN)
this workaround will get removed as these drivers get adjusted after
device tree based clock lookup has become available

the COMMON_CLK implementation copes with device trees which lack an
oscillator node (backwards compat), the REF clock is then derived from
the IPS bus frequency and multiplier values fetched from hardware

Cc: Mike Turquette <mturquette@linaro.org>
Cc: Anatolij Gustschin <agust@denx.de>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: NGerhard Sittig <gsi@denx.de>
Signed-off-by: NAnatolij Gustschin <agust@denx.de>