Our current switch_mm implementation suffers from a number of problems:

  (1) The ASID allocator relies on IPIs to synchronise the CPUs on a
      rollover event

  (2) Because of (1), we cannot allocate ASIDs with interrupts disabled
      and therefore make use of a TIF_SWITCH_MM flag to postpone the
      actual switch to finish_arch_post_lock_switch

  (3) We run context switch with a reserved (invalid) TTBR0 value, even
      though the ASID and pgd are updated atomically

  (4) We take a global spinlock (cpu_asid_lock) during context-switch

  (5) We use h/w broadcast TLB operations when they are not required
      (e.g. in flush_context)

This patch addresses these problems by rewriting the ASID algorithm to
match the bitmap-based arch/arm/ implementation more closely. This in
turn allows us to remove much of the complications surrounding switch_mm,
including the ugly thread flag.
Reviewed-by: NCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

Commit 68234df4 ("arm64: kill flush_cache_all()") removed
soft_reset() from the kernel. This was the only caller of
setup_mm_for_reboot(), so remove that also.
Signed-off-by: NMark Salter <msalter@redhat.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

Currently, the FDT blob needs to be in the same 512 MB region as
the kernel, so that it can be mapped into the kernel virtual memory
space very early on using a minimal set of statically allocated
translation tables.

Now that we have early fixmap support, we can relax this restriction,
by moving the permanent FDT mapping to the fixmap region instead.
This way, the FDT blob may be anywhere in memory.

This also moves the vetting of the FDT to mmu.c, since the early
init code in head.S does not handle mapping of the FDT anymore.
At the same time, fix up some comments in head.S that have gone stale.
Reviewed-by: NMark Rutland <mark.rutland@arm.com>
Tested-by: NMark Rutland <mark.rutland@arm.com>
Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

Now that we have moved the call to SetVirtualAddressMap() to the stub,
UEFI has no use for the ID map, so we can drop the code that installs
ID mappings for UEFI memory regions.
Acked-by: NLeif Lindholm <leif.lindholm@linaro.org>
Acked-by: NWill Deacon <will.deacon@arm.com>
Tested-by: NLeif Lindholm <leif.lindholm@linaro.org>
Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>

For UEFI, we need to install the memory mappings used for Runtime Services
in a dedicated set of page tables. Add create_pgd_mapping(), which allows
us to allocate and install those page table entries early.
Reviewed-by: NWill Deacon <will.deacon@arm.com>
Tested-by: NLeif Lindholm <leif.lindholm@linaro.org>
Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>

At boot time, before switching to a virtual UEFI memory map, firmware
expects UEFI memory and IO regions to be identity mapped whenever
kernel makes runtime services calls. The existing early boot code
creates an identity map of kernel text/data but this is not sufficient
for UEFI. This patch adds a create_id_mapping() function which reuses
the core code of the existing create_mapping().
Signed-off-by: NMark Salter <msalter@redhat.com>
[ Fixed error message formatting (%pa). ]
Signed-off-by: NMark Rutland <mark.rutland@arm.com>
Signed-off-by: NLeif Lindholm <leif.lindholm@linaro.org>
Acked-by: NCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: NMatt Fleming <matt.fleming@intel.com>

ARM64 has defined the spinlock for init_mm's context, so need initialize
the spinlock structure; otherwise during the suspend flow it will dump
the info for spinlock's bad magic warning as below:

[   39.084394] Disabling non-boot CPUs ...
[   39.092871] BUG: spinlock bad magic on CPU#1, swapper/1/0
[   39.092896]  lock: init_mm+0x338/0x3e0, .magic: 00000000, .owner: <none>/-1, .owner_cpu: 0
[   39.092907] CPU: 1 PID: 0 Comm: swapper/1 Tainted: G           O 3.10.33 #125
[   39.092912] Call trace:
[   39.092927] [<ffffffc000087e64>] dump_backtrace+0x0/0x16c
[   39.092934] [<ffffffc000087fe0>] show_stack+0x10/0x1c
[   39.092947] [<ffffffc000765334>] dump_stack+0x1c/0x28
[   39.092953] [<ffffffc0007653b8>] spin_dump+0x78/0x88
[   39.092960] [<ffffffc0007653ec>] spin_bug+0x24/0x34
[   39.092971] [<ffffffc000300a28>] do_raw_spin_lock+0x98/0x17c
[   39.092979] [<ffffffc00076cf08>] _raw_spin_lock_irqsave+0x4c/0x60
[   39.092990] [<ffffffc000094044>] set_mm_context+0x1c/0x6c
[   39.092996] [<ffffffc0000941c8>] __new_context+0x94/0x10c
[   39.093007] [<ffffffc0000d63d4>] idle_task_exit+0x104/0x1b0
[   39.093014] [<ffffffc00008d91c>] cpu_die+0x14/0x74
[   39.093021] [<ffffffc000084f74>] arch_cpu_idle_dead+0x8/0x14
[   39.093030] [<ffffffc0000e7f18>] cpu_startup_entry+0x1ec/0x258
[   39.093036] [<ffffffc00008d810>] secondary_start_kernel+0x114/0x124
Signed-off-by: NLeo Yan <leoy@marvell.com>
Acked-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

Presently, paging_init() calls init_mem_pgprot() to initialize pgprot
values used by macros such as PAGE_KERNEL, PAGE_KERNEL_EXEC, etc.

The new fixmap and early_ioremap support also needs to use these macros
before paging_init() is called.  This patch moves the init_mem_pgprot()
call out of paging_init() and into setup_arch() so that pgprot_default
gets initialized in time for fixmap and early_ioremap.
Signed-off-by: NMark Salter <msalter@redhat.com>
Acked-by: NCatalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Borislav Petkov <borislav.petkov@amd.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch adds support for "earlyprintk=" parameter on the kernel
command line. The format is:

  earlyprintk=<name>[,<addr>][,<options>]

where <name> is the name of the (UART) device, e.g. "pl011", <addr> is
the I/O address. The <options> aren't currently used.

The mapping of the earlyprintk device is done very early during kernel
boot and there are restrictions on which functions it can call. A
special early_io_map() function is added which creates the mapping from
the pre-defined EARLY_IOBASE to the device I/O address passed via the
kernel parameter. The pgd entry corresponding to EARLY_IOBASE is
pre-populated in head.S during kernel boot.

Only PL011 is currently supported and it is assumed that the interface
is already initialised by the boot loader before the kernel is started.
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
Acked-by: NArnd Bergmann <arnd@arndb.de>

The virtual memory layout is described in
Documentation/arm64/memory.txt. This patch adds the MMU definitions for
the 4KB and 64KB translation table configurations. The SECTION_SIZE is
2MB with 4KB page and 512MB with 64KB page configuration.

PHYS_OFFSET is calculated at run-time and stored in a variable (no
run-time code patching at this stage).

On the current implementation, both user and kernel address spaces are
512G (39-bit) each with a maximum of 256G for the RAM linear mapping.
Linux uses 3 levels of translation tables with the 4K page configuration
and 2 levels with the 64K configuration. Extending the memory space
beyond 39-bit with the 4K pages or 42-bit with 64K pages requires an
additional level of translation tables.

The SPARSEMEM configuration is global to all AArch64 platforms and
allows for 1GB sections with SPARSEMEM_VMEMMAP enabled by default.
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
Acked-by: NTony Lindgren <tony@atomide.com>
Acked-by: NNicolas Pitre <nico@linaro.org>
Acked-by: NOlof Johansson <olof@lixom.net>
Acked-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: NArnd Bergmann <arnd@arndb.de>

The patch adds the kernel booting and the initial setup code.
Documentation/arm64/booting.txt describes the booting protocol on the
AArch64 Linux kernel. This is subject to change following the work on
boot standardisation, ACPI.
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
Acked-by: NNicolas Pitre <nico@linaro.org>
Acked-by: NTony Lindgren <tony@atomide.com>
Acked-by: NOlof Johansson <olof@lixom.net>
Acked-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: NArnd Bergmann <arnd@arndb.de>

Add support for the Infineon TLE62x0 series of low-side driver chips, such
as the TLE6220 or TLE6230.  These can be viewed as output GPIOs specialized
for power switching applications.  The driver provides a userspace
interface to those GPIOs, and to the switch status they provide.
Signed-off-by: NBen Dooks <ben-linux@fluff.org>
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Patch from Sascha Hauer

This patch adds the base support for Hilscher's netX network
processors.
Signed-off-by: NRobert Schwebel <r.schwebel@pengutronix.de>
Signed-off-by: NSascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Patch from SAN People

Following changes were made to clock.c:

1) Replaced <asm/hardware/clock.h> with <linux/clk.h>
2) Removed old unused clk_enable & clk_disable.
3) Replaced clk_use/clk_unuse with clk_enable/clk_disable.

Otherwise it's the same as the previous patch.
Signed-off-by: NAndrew Victor <andrew@sanpeople.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Rationalise hardware.h include.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!