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| author | Russell King (Oracle) <rmk+kernel@armlinux.org.uk> | 2023-06-27 14:17:19 +0100 |
|---|---|---|
| committer | Russell King (Oracle) <rmk+kernel@armlinux.org.uk> | 2023-06-27 14:17:19 +0100 |
| commit | 53ae158f6ddc14df5c44d62c06e33fdb66de1196 (patch) | |
| tree | d0d0485f5f614e0070bab6ff1b53d56aec7c2d8e /arch/arm/kernel/iwmmxt.S | |
| parent | ac9a78681b921877518763ba0e89202254349d1b (diff) | |
| parent | 47ba5f39eab3c2a9a1ba878159a6050f2bbfc0e2 (diff) | |
Merge tag 'arm-vfp-refactor-for-rmk' of git://git.kernel.org/pub/scm/linux/kernel/git/ardb/linux into devel-stabledevel-stable
Refactor VFP support code and reimplement in C
The VFP related changes to permit kernel mode NEON in softirq context
resulted in some issues regarding en/disabling of sofirqs from asm code,
and this made it clear that it would be better to handle more of it from
C code.
Given that we already have infrastructure that associates undefined
instruction exceptions with handler code based on value/mask pairs, we
can easily move the dispatch of VFP and NEON instructions to C code once
we reimplement the actual VFP support routine (which reasons about how
to deal with the exception and whether any emulation is needed) in C
code first.
With those out of the way, we can drop the partial decoding logic in asm
that reasons about which ISA is being used by user space, as the
remaining cases are all 32-bit ARM only. This leaves a FPE specific
routine with some iWMMXT logic that is easily duplicated in C as well,
allowing us to move the FPE asm code into the FPE asm source file, and
out of the shared entry code.
Diffstat (limited to 'arch/arm/kernel/iwmmxt.S')
| -rw-r--r-- | arch/arm/kernel/iwmmxt.S | 18 |
1 files changed, 14 insertions, 4 deletions
diff --git a/arch/arm/kernel/iwmmxt.S b/arch/arm/kernel/iwmmxt.S index d2b4ac06e4ed..a0218c4867b9 100644 --- a/arch/arm/kernel/iwmmxt.S +++ b/arch/arm/kernel/iwmmxt.S @@ -58,9 +58,19 @@ .text .arm +ENTRY(iwmmxt_undef_handler) + push {r9, r10, lr} + get_thread_info r10 + mov r9, pc + b iwmmxt_task_enable + mov r0, #0 + pop {r9, r10, pc} +ENDPROC(iwmmxt_undef_handler) + /* * Lazy switching of Concan coprocessor context * + * r0 = struct pt_regs pointer * r10 = struct thread_info pointer * r9 = ret_from_exception * lr = undefined instr exit @@ -84,12 +94,12 @@ ENTRY(iwmmxt_task_enable) PJ4(mcr p15, 0, r2, c1, c0, 2) ldr r3, =concan_owner - add r0, r10, #TI_IWMMXT_STATE @ get task Concan save area - ldr r2, [sp, #60] @ current task pc value + ldr r2, [r0, #S_PC] @ current task pc value ldr r1, [r3] @ get current Concan owner - str r0, [r3] @ this task now owns Concan regs sub r2, r2, #4 @ adjust pc back - str r2, [sp, #60] + str r2, [r0, #S_PC] + add r0, r10, #TI_IWMMXT_STATE @ get task Concan save area + str r0, [r3] @ this task now owns Concan regs mrc p15, 0, r2, c2, c0, 0 mov r2, r2 @ cpwait |