clk: at91: sync with Linux v5.8-rc1 ...

This ports over a couple of changes that accrued upstream between v5.6,
when we last synchronized, and v5.8-rc1:

  5bf7f4a24938 clk: at91: sam9x60: Don't use audio PLL
  b0ecf1c6c6e8 clk: at91: usb: continue if clk_hw_round_rate() return zero
  43b203d32b77 clk: at91: sam9x60: fix usb clock parents
  d7a83d67a169 clk: at91: usb: use proper usbs_mask
  9962fb0d1995 clk: at91: usb: introduce num_parents in driver's structure
  12dc8d3be9d8 clk: at91: add at91sam9g45 pmc driver
  0969b242f7b8 clk: at91: add sama5d3 pmc driver
  143e04dab6b4 clk: at91: add at91sam9n12 pmc driver
  02ff48e4d7f7 clk: at91: add at91rm9200 pmc driver
  99e107439eea clk: at91: Add peripheral clock for PTC
  f6363c437dc6 clk: at91: pmc: do not continue if compatible not located
  7425f246f725 clk: at91: optimize pmc data allocation
  99767cd4406f clk: at91: allow setting PCKx parent via DT
  03a1ee1dad0e clk: at91: allow setting all PMC clock parents via DT

Besides fixes, mostly around sam9x60, this adds support for the new
a91 device tree clock bindings that were extended to the sama5d3 in v5.8-rc1.

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

clk: at91: port Linux v5.6 SAM9X60 (new ARM926EJ-S) clock support ...

During a bug hunt that ultimately turned out unrelated to the state
of the barebox at91 clk driver, I synchronized its state with Linux v5.6.

Bug fixes and clean up to minimize the diff were split out in separate
prior commits.  This last commit imports the rest, which is basically
support for Microchip's new ARM926EJ-S SoC, the SAM9x60.

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

clk: at91: add __init marker where appropriate ...

While redundant in barebox, it makes our diff to the upstream driver
smaller when synchronizing, so add it back.

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

clk: migrate to SPDX-License-Identifier use ...

Some of these are a product of source sync with Linux, the other were
done with macro assistance by searching for /later/, deleting license text,
adding appropriate SPDX-License-Identifier and manual post-review.

Devices without a license indicated where assumed GPL-2.0-only according
with the project's license.

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

clk: at91: update to PMC bindings ...

Based on kernel 5.0-rc6 update at91 clk support
to match the new PMC bindings.

Manually added all changes done in the kernel from 4.9-rc3 to 5.0-rc6.
New drivers required was added as seperate commits.

This includes dt-compat code required to support at91sam5d3,
as this is not yet ported to use the new PMC bindings.

clk-programmable saw some extra changes - it had never been bulit.
It is used only by at91sama5d2 - and barebox has no board support for
this cpu (yet).

The CONFIG_SOC symbols is used to select the relevant drivers.
CONFIG_SOC_SAM9 selects several drivers, and in the future
this can be split to keep the image size down.

In the kernel CLK_OF_DECLARE_DRIVER() can be used for a two step init.
In barebox this is a simple one step init.
It was added to have less differences between the kernel and the barebox
versions of the drivers.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Tested-by: Ladislav Michl <ladis@linux-mips.org>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

clk: at91: Port at91 DT clock code ...

Port at91 DT clock code from Linux 4.9-rc3.

Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>