XIP (eXecute In Place) kernel image is the image that can be run
directly from ROM, using RAM only for writable data.

XIP xtensa kernel differs from regular xtensa kernel in the following
ways:
- it has exception/IRQ vectors merged into text section. No vectors
  relocation takes place at kernel startup.
- .data/.bss location must be specified in the kernel configuration,
  its content is copied there in the _startup function.
- .init.text is merged with the rest of text and is executed from ROM.
- when MMU is used the virtual address where the kernel will be mapped
  must be specified in the kernel configuration. It may be in the KSEG
  or in the KIO, __pa macro is adjusted to be able to handle both.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

The xtensa free_initrd_mem() verifies that initrd is mapped and then
frees its memory using free_reserved_area().

The initrd is considered mapped when its memory was successfully reserved
with mem_reserve().

Resetting initrd_start to 0 in case of mem_reserve() failure allows to
switch to generic free_initrd_mem() implementation.

Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Message-Id: <1563977432-8376-1-git-send-email-rppt@linux.ibm.com>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

ITLB entry modifications must be followed by the isync instruction
before the new entries are possibly used. cpu_reset lacks one isync
between ITLB way 6 initialization and jump to the identity mapping.
Add missing isync to xtensa cpu_reset.

Cc: stable@vger.kernel.org
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

xtensa-specific PCI initialization code has significantly bitrotted over
time because there's no platform that use it. Get rid of remaining
non-functioning initialization and remove platform_pcibios_* interface.
A new platform that would use PCI on xtensa will configure PCI
controller using device tree.

Drop variables pci_ctrl_head, pci_bus_count and functions pcibios_init,
pci_controller_apertures, platform_pcibios_init and
platform_pcibios_fixup.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

Since commit 9012d011660ea5cf2 ("compiler: allow all arches to enable
CONFIG_OPTIMIZE_INLINING"), xtensa:tinyconfig fails to build with section
mismatch errors.

WARNING: vmlinux.o(.text.unlikely+0x68): Section mismatch in reference
	from the function ___pa()
	to the function .meminit.text:memblock_reserve()
WARNING: vmlinux.o(.text.unlikely+0x74): Section mismatch in reference
	from the function mem_reserve()
	to the function .meminit.text:memblock_reserve()
FATAL: modpost: Section mismatches detected.

This was not seen prior to the above mentioned commit because mem_reserve()
was always inlined.

Mark mem_reserve(() as __init_memblock to have it reside in the same
section as memblock_reserve().

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Message-Id: <1559220098-9955-1-git-send-email-linux@roeck-us.net>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

Implement atomic primitives using exclusive access opcodes available in
the recent xtensa cores.
Since l32ex/s32ex don't have any memory ordering guarantees don't define
__smp_mb__before_atomic/__smp_mb__after_atomic to make them use memw.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

WSR and RSR are too generic and collide with other macro definitions in
the kernel causing warnings in allmodconfig builds. Drop WSR and RSR
macros and WSR_* and RSR_* variants. Change get_sr and set_sr to
xtensa_get_sr and xtensa_set_sr. Fix up users.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

A kernel may not need any boot parameters from the bootloader, allow
disabling bootparam parsing in that case.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

platform/hardware.h no longer supply any information for processor.h,
vectors.h, setup.c or vmlinux.lds.S, don't include it.
This header is now empty in the platforms/iss, so remove it altogether.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

Pull DeviceTree updates from Rob Herring:

 - Convert to use memblock_virt_alloc in DT code which supports
   bootmem arches. With this we can remove the arch specific
   early_init_dt_alloc_memory_arch() functions.

 - Enable running the DT unittests on UML

 - Use SPDX license tags on DT files

 - Fix early FDT kconfig ifdef logic

 - Clean-up unittest Makefile

 - Fix function comment for of_irq_parse_raw

 - Add missing documentation for linux,initrd-{start,end} properties

 - Clean-up of binding examples using uppercase hex

 - Add trivial devices W83773G and Infineon TLV493D-A1B6

 - Add missing STM32 SoC bindings

 - Various small binding doc fixes

* tag 'devicetree-for-4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (23 commits)
  xtensa: remove arch specific early DT functions
  x86: remove arch specific early_init_dt_alloc_memory_arch
  nios2: remove arch specific early_init_dt_alloc_memory_arch
  mips: remove arch specific early_init_dt_alloc_memory_arch
  metag: remove arch specific early DT functions
  cris: remove arch specific early DT functions
  libfdt: remove unnecessary include directive from <linux/libfdt.h>
  of: unittest: refactor Makefile
  of/fdt: use memblock_virt_alloc for early alloc
  of: Use SPDX license tag for DT files
  of/fdt: Fix #ifdef dependency of early flattree declarations
  dt-bindings: h8300 clocksource: correct spelling of pulse
  dt-bindings: imx6q-pcie: Add required property for i.MX6SX
  mmc: Don't reference Linux-specific OF_GPIO_ACTIVE_LOW flag in DT binding
  dt-bindings: Use lower case hex in unit-addresses
  dt-bindings: display: panel: Fix compatible string for Toshiba LT089AC29000
  dt-bindings: Add Infineon TLV493D-A1B6
  dt-bindings: mailbox: ti,message-manager: Fix interrupt name error
  dt-bindings: chosen: Document linux,initrd-{start,end}
  dt-bindings: arm: document supported STM32 SoC family
  ...