cannot_instantiate_with_device_add_yet was introduced by commit
efec3dd6 to replace no_user. It was
supposed to be a temporary measure.

When it was introduced, we had 54
cannot_instantiate_with_device_add_yet=true lines in the code.
Today (3 years later) this number has not shrunk: we now have
57 cannot_instantiate_with_device_add_yet=true lines. I think it
is safe to say it is not a temporary measure, and we won't see
the flag go away soon.

Instead of a long field name that misleads people to believe it
is temporary, replace it a shorter and less misleading field:
user_creatable.

Except for code comments, changes were generated using the
following Coccinelle patch:

  @@
  expression DC;
  @@
  (
  -DC->cannot_instantiate_with_device_add_yet = false;
  +DC->user_creatable = true;
  |
  -DC->cannot_instantiate_with_device_add_yet = true;
  +DC->user_creatable = false;
  )

  @@
  typedef ObjectClass;
  expression dc;
  identifier class, data;
  @@
   static void device_class_init(ObjectClass *class, void *data)
   {
   ...
   dc->hotpluggable = true;
  +dc->user_creatable = true;
   ...
   }

  @@
  @@
   struct DeviceClass {
   ...
  -bool cannot_instantiate_with_device_add_yet;
  +bool user_creatable;
   ...
  }

  @@
  expression DC;
  @@
  (
  -!DC->cannot_instantiate_with_device_add_yet
  +DC->user_creatable
  |
  -DC->cannot_instantiate_with_device_add_yet
  +!DC->user_creatable
  )

Cc: Alistair Francis <alistair.francis@xilinx.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Marcel Apfelbaum <marcel@redhat.com>
Cc: Markus Armbruster <armbru@redhat.com>
Cc: Peter Maydell <peter.maydell@linaro.org>
Cc: Thomas Huth <thuth@redhat.com>
Acked-by: NAlistair Francis <alistair.francis@xilinx.com>
Reviewed-by: NThomas Huth <thuth@redhat.com>
Reviewed-by: NMarcel Apfelbaum <marcel@redhat.com>
Acked-by: NMarcel Apfelbaum <marcel@redhat.com>
Signed-off-by: NEduardo Habkost <ehabkost@redhat.com>
Message-Id: <20170503203604.31462-2-ehabkost@redhat.com>
[ehabkost: kept "TODO remove once we're there" comment]
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NEduardo Habkost <ehabkost@redhat.com>

The register_read() and register_write() functions expect a bitmask argument.
To avoid duplicated code, a new inlined function register_enabled_mask() is
introduced.
Signed-off-by: NPhilippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: NAlistair Francis <alistair.francis@xilinx.com>
Signed-off-by: NMichael Tokarev <mjt@tls.msk.ru>

The "qemu,register" device needs to be wired up in source code, there
is no way the user can make any real use of this device with the
"-device" parameter or the "device_add" monitor command yet.
Signed-off-by: NThomas Huth <thuth@redhat.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NAlistair Francis <alistair.francis@xilinx.com>
Signed-off-by: NMichael Tokarev <mjt@tls.msk.ru>

Add a helper that will scan a static RegisterAccessInfo Array
and populate a container MemoryRegion with registers as defined.
Signed-off-by: NPeter Crosthwaite <peter.crosthwaite@xilinx.com>
Signed-off-by: NAlistair Francis <alistair.francis@xilinx.com>
Message-id: 347b810b2799e413c98d5bbeca97bcb1557946c3.1467053537.git.alistair.francis@xilinx.com
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

QOMify registers as a child of TYPE_DEVICE. This allows registers to
define GPIOs.

Define an init helper that will do QOM initialisation.
Signed-off-by: NPeter Crosthwaite <peter.crosthwaite@xilinx.com>
Signed-off-by: NAlistair Francis <alistair.francis@xilinx.com>
Reviewed-by: NKONRAD Frederic <fred.konrad@greensocs.com>
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Message-id: 2545f71db26bf5586ca0c08a3e3cf1b217450552.1467053537.git.alistair.francis@xilinx.com
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Add memory io handlers that glue the register API to the memory API.
Just translation functions at this stage. Although it does allow for
devices to be created without all-in-one mmio r/w handlers.

This patch also adds the RegisterInfoArray struct, which allows all of
the individual RegisterInfo structs to be grouped into a single memory
region.
Signed-off-by: NPeter Crosthwaite <peter.crosthwaite@xilinx.com>
Signed-off-by: NAlistair Francis <alistair.francis@xilinx.com>
Message-id: f7704d8ac6ac0f469ed35401f8151a38bd01468b.1467053537.git.alistair.francis@xilinx.com
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

This API provides some encapsulation of registers and factors out some
common functionality to common code. Bits of device state (usually MMIO
registers) often have all sorts of access restrictions and semantics
associated with them. This API allows you to define what those
restrictions are on a bit-by-bit basis.

Helper functions are then used to access the register which observe the
semantics defined by the RegisterAccessInfo struct.

Some features:
Bits can be marked as read_only (ro field)
Bits can be marked as write-1-clear (w1c field)
Bits can be marked as reserved (rsvd field)
Reset values can be defined (reset)
Bits can be marked clear on read (cor)
Pre and post action callbacks can be added to read and write ops
Verbose debugging info can be enabled/disabled

Useful for defining device register spaces in a data driven way. Cuts
down on a lot of the verbosity and repetition in the switch-case blocks
in the standard foo_mmio_read/write functions.

Also useful for automated generation of device models from hardware
design sources.
Signed-off-by: NPeter Crosthwaite <peter.crosthwaite@xilinx.com>
Signed-off-by: NAlistair Francis <alistair.francis@xilinx.com>
Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Message-id: 40d62c7e1bf6e63bb4193ec46b15092a7d981e59.1467053537.git.alistair.francis@xilinx.com
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>