linux.git/arch/arm/kernel/head.S, branch v6.12.80

ARM: 9420/1: smp: Fix SMP for xip kernels

2024-11-12T16:38:47+00:00

Fix the physical address calculation of the following to get smp working
on xip kernels.
- secondary_data needed for secondary cpu bootup.
- secondary_startup address passed through psci.
- identity mapped code region needed for enabling mmu for secondary cpus.

Signed-off-by: Harith George 
Reviewed-by: Linus Walleij 
Signed-off-by: Russell King (Oracle)

ARM: 9419/1: mm: Fix kernel memory mapping for xip kernels

2024-11-12T16:38:46+00:00

The patchset introducing kernel_sec_start/end variables to separate the
kernel/lowmem memory mappings, broke the mapping of the kernel memory
for xipkernels.

kernel_sec_start/end variables are in RO area before the MMU is switched
on for xipkernels.
So these cannot be set early in boot in head.S. Fix this by setting these
after MMU is switched on.
xipkernels need two different mappings for kernel text (starting at
CONFIG_XIP_PHYS_ADDR) and data (starting at CONFIG_PHYS_OFFSET).
Also, move the kernel code mapping from devicemaps_init() to map_kernel().

Fixes: a91da5457085 ("ARM: 9089/1: Define kernel physical section start and end")
Signed-off-by: Harith George 
Reviewed-by: Linus Walleij 
Signed-off-by: Russell King (Oracle)

ARM: mm: Make virt_to_pfn() a static inline

2023-05-29T09:27:08+00:00

Making virt_to_pfn() a static inline taking a strongly typed
(const void *) makes the contract of a passing a pointer of that
type to the function explicit and exposes any misuse of the
macro virt_to_pfn() acting polymorphic and accepting many types
such as (void *), (unitptr_t) or (unsigned long) as arguments
without warnings.

Doing this is a bit intrusive: virt_to_pfn() requires
PHYS_PFN_OFFSET and PAGE_SHIFT to be defined, and this is defined in
, so this must be included *before* .

The use of macros were obscuring the unclear inclusion order here,
as the macros would eventually be resolved, but a static inline
like this cannot be compiled with unresolved macros.

The naive solution to include  at the top of
 does not work, because  sometimes
includes  at the end of itself, which would create a
confusing inclusion loop. So instead, take the approach to always
unconditionally include  at the end of 

arch/arm uses  explicitly in a lot of places,
however it turns out that if we just unconditionally include
 into  and switch all inclusions of
 to  instead, we enforce the right
order and  will always have access to the
definitions.

Put an inclusion guard in place making it impossible to include
 explicitly.

Link: https://lore.kernel.org/linux-mm/20220701160004.2ffff4e5ab59a55499f4c736@linux-foundation.org/
Signed-off-by: Linus Walleij

ARM: footbridge: remove CATS

2023-01-10T22:10:27+00:00

Nobody seems to have a CATS machine any more, so remove
it now, leaving only NetWinder and EBSA285.

Cc: Russell King 
Acked-by: Linus Walleij 
Signed-off-by: Arnd Bergmann

ARM: head.S: rename PMD_ORDER to PMD_ENTRY_ORDER

2022-07-18T00:14:44+00:00

PMD_ORDER denotes order of magnitude for a PMD entry, i.e PMD entry size
is 2 ^ PMD_ORDER.

Rename PMD_ORDER to PMD_ENTRY_ORDER to allow a generic definition of
PMD_ORDER as order of a PMD allocation: (PMD_SHIFT - PAGE_SHIFT).

Link: https://lkml.kernel.org/r/20220705154708.181258-16-rppt@kernel.org
Signed-off-by: Mike Rapoport 
Acked-by: Russell King (Oracle) 
Signed-off-by: Andrew Morton

ARM: mm: switch to swapper_pg_dir early for vmap'ed stack

2022-01-24T19:37:55+00:00

When onlining a CPU, switch to swapper_pg_dir as soon as possible so
that it is guaranteed that the vmap'ed stack is mapped before it is
used.

Signed-off-by: Ard Biesheuvel

Merge branches 'devel-stable' and 'misc' into for-linus

2021-11-02T09:04:22+00:00

ARM: 9148/1: handle CONFIG_CPU_ENDIAN_BE32 in arch/arm/kernel/head.S

2021-10-25T12:11:34+00:00

My intel-ixp42x-welltech-epbx100 no longer boot since 4.14.
This is due to commit 463dbba4d189 ("ARM: 9104/2: Fix Keystone 2 kernel
mapping regression")
which forgot to handle CONFIG_CPU_ENDIAN_BE32 as possible BE config.

Suggested-by: Krzysztof Hałasa 
Fixes: 463dbba4d189 ("ARM: 9104/2: Fix Keystone 2 kernel mapping regression")
Signed-off-by: Corentin Labbe 
Signed-off-by: Russell King (Oracle)

ARM: smp: Pass task to secondary_start_kernel

2021-09-27T14:54:01+00:00

This avoids needing to compute the task pointer in this function, which
will no longer be possible once we move thread_info off the stack.

Signed-off-by: Keith Packard 
Signed-off-by: Ard Biesheuvel 
Reviewed-by: Linus Walleij 
Tested-by: Amit Daniel Kachhap

ARM: 9104/2: Fix Keystone 2 kernel mapping regression

2021-08-10T11:17:25+00:00

This fixes a Keystone 2 regression discovered as a side effect of
defining an passing the physical start/end sections of the kernel
to the MMU remapping code.

As the Keystone applies an offset to all physical addresses,
including those identified and patches by phys2virt, we fail to
account for this offset in the kernel_sec_start and kernel_sec_end
variables.

Further these offsets can extend into the 64bit range on LPAE
systems such as the Keystone 2.

Fix it like this:
- Extend kernel_sec_start and kernel_sec_end to be 64bit
- Add the offset also to kernel_sec_start and kernel_sec_end

As passing kernel_sec_start and kernel_sec_end as 64bit invariably
incurs BE8 endianness issues I have attempted to dry-code around
these.

Tested on the Vexpress QEMU model both with and without LPAE
enabled.

Fixes: 6e121df14ccd ("ARM: 9090/1: Map the lowmem and kernel separately")
Reported-by: Nishanth Menon 
Suggested-by: Russell King 
Tested-by: Grygorii Strashko 
Tested-by: Nishanth Menon 
Signed-off-by: Linus Walleij 
Signed-off-by: Russell King (Oracle)