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| author | Ard Biesheuvel <ardb@kernel.org> | 2021-12-02 09:36:59 +0100 |
|---|---|---|
| committer | Ard Biesheuvel <ardb@kernel.org> | 2021-12-06 12:49:17 +0100 |
| commit | cafc0eab168917ec9c0cd47d530a40cd40eb2928 (patch) | |
| tree | 92146e58caa9f383a8a6894aeeaa54bb1c563f7f /arch/arm/kernel | |
| parent | ARM: implement THREAD_INFO_IN_TASK for uniprocessor systems (diff) | |
| download | linux-cafc0eab168917ec9c0cd47d530a40cd40eb2928.tar.xz linux-cafc0eab168917ec9c0cd47d530a40cd40eb2928.zip | |
ARM: v7m: enable support for IRQ stacks
Enable support for IRQ stacks on !MMU, and add the code to the IRQ entry
path to switch to the IRQ stack if not running from it already.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Marc Zyngier <maz@kernel.org>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
Diffstat (limited to 'arch/arm/kernel')
| -rw-r--r-- | arch/arm/kernel/entry-v7m.S | 17 |
1 files changed, 15 insertions, 2 deletions
diff --git a/arch/arm/kernel/entry-v7m.S b/arch/arm/kernel/entry-v7m.S index 4e0d318b67c6..de8a60363c85 100644 --- a/arch/arm/kernel/entry-v7m.S +++ b/arch/arm/kernel/entry-v7m.S @@ -40,11 +40,24 @@ __irq_entry: @ Invoke the IRQ handler @ mov r0, sp - stmdb sp!, {lr} + ldr_this_cpu sp, irq_stack_ptr, r1, r2 + + @ + @ If we took the interrupt while running in the kernel, we may already + @ be using the IRQ stack, so revert to the original value in that case. + @ + subs r2, sp, r0 @ SP above bottom of IRQ stack? + rsbscs r2, r2, #THREAD_SIZE @ ... and below the top? + movcs sp, r0 + + push {r0, lr} @ preserve LR and original SP + @ routine called with r0 = struct pt_regs * bl generic_handle_arch_irq - pop {lr} + pop {r0, lr} + mov sp, r0 + @ @ Check for any pending work if returning to user @ |