kernel/linux.git/arch/powerpc/Kconfig.debug, branch v7.0.11

powerpc: fix dead default for GUEST_STATE_BUFFER_TEST

2026-06-01T15:54:38+00:00

[ Upstream commit aef656a0e6c01796190bb5bd2bdba1c644ed7811 ] The GUEST_STATE_BUFFER_TEST config option should default to KUNIT_ALL_TESTS so that if all tests are enabled then it is included, but currently the 'default KUNIT_ALL_TESTS' statement is shadowed by 'def_tristate n', meaning that this second default statement is currently dead code. It looks to me like the commit 6ccbbc33f06a ("KVM: PPC: Add helper library for Guest State Buffers") intended to set the default to KUNIT_ALL_TESTS, but mistakenly missed the def_tristate. This dead code was found by kconfirm, a static analysis tool for Kconfig. Fixes: 6ccbbc33f06a ("KVM: PPC: Add helper library for Guest State Buffers") Signed-off-by: Julian Braha Tested-by: Gautam Menghani Reviewed-by: Amit Machhiwal Reviewed-by: Harsh Prateek Bora Signed-off-by: Madhavan Srinivasan Link: https://patch.msgid.link/20260405161545.161006-1-julianbraha@gmail.com Signed-off-by: Sasha Levin

powerpc: Remove UDBG_RTAS_CONSOLE

2025-02-26T15:45:09+00:00

The IBM Cell blade support was the last user of UDBG_RTAS_CONSOLE. Although it's still possible to build it via PPC_EARLY_DEBUG_UDBG_RTAS_CONSOLE, AFAIK it's not useful on any other platfoms, because only Cell and JS20 era machines provided the RTAS get/put-term-char functions. If anyone is using it or needs it we can always resurrect it from git. Signed-off-by: Michael Ellerman Signed-off-by: Madhavan Srinivasan Link: https://patch.msgid.link/20241218105523.416573-19-mpe@ellerman.id.au

powerpc/64: Remove maple platform

2024-10-29T12:01:52+00:00

The maple platform was added in 2004 [1], to support the "Maple" 970FX evaluation board. It was later used for IBM JS20/JS21 machines, as well as the Bimini machine, aka "Yellow Dog Powerstation". Sadly all those machines have passed into memory, and there's been no evidence for years that anyone is still using any of them. Remove the platform and related code. It can always be reinstated if there's interest. Note that this has no impact on support for 970FX based Power Macs. [1]: https://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux-fullhistory.git/commit/?id=f0d068d65c5e555ffcfbc189de32598f6f00770c Signed-off-by: Michael Ellerman Link: https://patch.msgid.link/20241013102957.548291-1-mpe@ellerman.id.au

powerpc/64s: Remove the "fast endian switch" syscall

2024-09-05T12:30:05+00:00

The non-standard "fast endian switch" syscall was added in 2008[1], but was never widely used. It was disabled by default in 2017[2], and there's no evidence it's ever been used since. Remove it entirely. A normal endian switch syscall was added in 2015[3]. [1]: 745a14cc264b ("[POWERPC] Add fast little-endian switch system call") [2]: 529d235a0e19 ("powerpc: Add a proper syscall for switching endianness") [3]: 727f13616c45 ("powerpc: Disable the fast-endian switch syscall by default") Signed-off-by: Michael Ellerman Link: https://msgid.link/20240823070830.1269033-1-mpe@ellerman.id.au

powerpc: Remove 40x from Kconfig and defconfig

2024-06-28T12:28:47+00:00

Remove 40x from Kconfig, making the code unreachable. Signed-off-by: Michael Ellerman Link: https://msgid.link/20240628121201.130802-3-mpe@ellerman.id.au

powerpc/ps3: move udbg_shutdown_ps3gelic prototype

2023-11-21T01:06:50+00:00

Allmodconfig kernels produce a missing-prototypes warning: arch/powerpc/platforms/ps3/gelic_udbg.c:239:6: error: no previous prototype for 'udbg_shutdown_ps3gelic' [-Werror=missing-prototypes] Move the declaration from a local header to asm/ps3.h where it can be seen from both the caller and the definition. Signed-off-by: Arnd Bergmann Signed-off-by: Geoff Levand Acked-by: Jakub Kicinski [mpe: Drop CONFIG_PS3GELIC_UDBG to fix build error] Signed-off-by: Michael Ellerman Link: https://msgid.link/20231108125843.3806765-18-arnd@kernel.org

Merge branch 'topic/ppc-kvm' into next

2023-10-27T09:58:03+00:00

Merge our KVM topic branch, this has been independently included in linux-next for most of the development cycle.

powerpc: Use shared font data

2023-10-01T12:09:02+00:00

PowerPC has a 'btext' font used for the console which is almost identical to the shared font_sun8x16, so use it rather than duplicating the data. They were actually identical until about a decade ago when commit bcfbeecea11c ("drivers: console: font_: Change a glyph from "broken bar" to "vertical line"") which changed the | in the shared font to be a solid bar rather than a broken bar. That's the only difference. This was originally spotted by the PMF source code analyser, which noticed that sparc does the same thing with the same data, and they also share a bunch of functions to manipulate the data. I've previously posted a near identical patch for sparc. Tested very lightly with a boot without FS in qemu. Signed-off-by: "Dr. David Alan Gilbert" Signed-off-by: Michael Ellerman Link: https://msgid.link/20230825142754.1487900-1-linux@treblig.org

KVM: PPC: Add helper library for Guest State Buffers

2023-09-14T12:04:24+00:00

The PAPR "Nestedv2" guest API introduces the concept of a Guest State Buffer for communication about L2 guests between L1 and L0 hosts. In the new API, the L0 manages the L2 on behalf of the L1. This means that if the L1 needs to change L2 state (e.g. GPRs, SPRs, partition table...), it must request the L0 perform the modification. If the nested host needs to read L2 state likewise this request must go through the L0. The Guest State Buffer is a Type-Length-Value style data format defined in the PAPR which assigns all relevant partition state a unique identity. Unlike a typical TLV format the length is redundant as the length of each identity is fixed but is included for checking correctness. A guest state buffer consists of an element count followed by a stream of elements, where elements are composed of an ID number, data length, then the data: Header: <---4 bytes---> +----------------+----- | Element Count | Elements... +----------------+----- Element: <----2 bytes---> <-2 bytes-> <-Length bytes-> +----------------+-----------+----------------+ | Guest State ID | Length | Data | +----------------+-----------+----------------+ Guest State IDs have other attributes defined in the PAPR such as whether they are per thread or per guest, or read-only. Introduce a library for using guest state buffers. This includes support for actions such as creating buffers, adding elements to buffers, reading the value of elements and parsing buffers. This will be used later by the nestedv2 guest support. Signed-off-by: Jordan Niethe Signed-off-by: Michael Ellerman Link: https://msgid.link/20230914030600.16993-9-jniethe5@gmail.com

powerpc: allow PPC_EARLY_DEBUG_CPM only when SERIAL_CPM=y

2023-07-03T06:07:55+00:00

In a randconfig with CONFIG_SERIAL_CPM=m and CONFIG_PPC_EARLY_DEBUG_CPM=y, there is a build error: ERROR: modpost: "udbg_putc" [drivers/tty/serial/cpm_uart/cpm_uart.ko] undefined! Prevent the build error by allowing PPC_EARLY_DEBUG_CPM only when SERIAL_CPM=y. Fixes: c374e00e17f1 ("[POWERPC] Add early debug console for CPM serial ports.") Signed-off-by: Randy Dunlap Reviewed-by: Pali Rohár Reviewed-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://msgid.link/20230701054714.30512-1-rdunlap@infradead.org