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2021-10-28powerpc/dcr: Use cmplwi instead of 3-argument cmpliMichael Ellerman1-1/+1
In dcr-low.S we use cmpli with three arguments, instead of four arguments as defined in the ISA: cmpli cr0,r3,1024 This appears to be a PPC440-ism, looking at the "PPC440x5 CPU Core User’s Manual" it shows cmpli having no L field, but implied to be 0 due to the core being 32-bit. It mentions that the ISA defines four arguments and recommends using cmplwi. It also corresponds to the old POWER instruction set, which had no L field there, a reserved bit instead. dcr-low.S is only built 32-bit, because it is only built when DCR_NATIVE=y, which is only selected by 40x and 44x. Looking at the generated code (with gcc/gas) we see cmplwi as expected. Although gas is happy with the 3-argument version when building for 32-bit, the LLVM assembler is not and errors out with: arch/powerpc/sysdev/dcr-low.S:27:10: error: invalid operand for instruction cmpli 0,%r3,1024; ... ^ Switch to the cmplwi extended opcode, which avoids any confusion when reading the ISA, fixes the issue with the LLVM assembler, and also means the code could be built 64-bit in future (though that's very unlikely). Reported-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> BugLink: https://github.com/ClangBuiltLinux/linux/issues/1419 Link: https://lore.kernel.org/r/20211014024424.528848-1-mpe@ellerman.id.au
2019-05-30treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152Thomas Gleixner1-5/+1
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 3029 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-08ppc: move exports to definitionsAl Viro1-0/+3
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-12-21powerpc/4xx: Extended DCR support v2Benjamin Herrenschmidt1-1/+7
This adds supports to the "extended" DCR addressing via the indirect mfdcrx/mtdcrx instructions supported by some 4xx cores (440H6 and later). I enabled the feature for now only on AMCC 460 chips. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by: Josh Boyer <jwboyer@linux.vnet.ibm.com> Acked-by: Kumar Gala <galak@kernel.crashing.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-12-04[POWERPC] Generic DCR infrastructureBenjamin Herrenschmidt1-0/+39
This patch adds new dcr_map/dcr_read/dcr_write accessors for DCRs that can be used by drivers to transparently address either native DCRs or memory mapped DCRs. The implementation for memory mapped DCRs is done after the binding being currently worked on for SLOF and the Axon chipset. This patch enables it for the cell native platform Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Paul Mackerras <paulus@samba.org>