linux-stable.git/arch/mips/kernel/cpu-probe.c, branch linux-6.6.y

MIPS: Always record SEGBITS in cpu_data.vmbits

2026-04-18T08:39:50+00:00

commit 8374c2cb83b95b3c92f129fd56527225c20a058c upstream.

With a 32-bit kernel running on 64-bit MIPS hardware the hardcoded value
of `cpu_vmbits' only records the size of compatibility useg and does not
reflect the size of native xuseg or the complete range of values allowed
in the VPN2 field of TLB entries.

An upcoming change will need the actual VPN2 value range permitted even
in 32-bit kernel configurations, so always include the `vmbits' member
in `struct cpuinfo_mips' and probe for SEGBITS when running on 64-bit
hardware and resorting to the currently hardcoded value of 31 on 32-bit
processors.  No functional change for users of `cpu_vmbits'.

Signed-off-by: Maciej W. Rozycki 
Signed-off-by: Thomas Bogendoerfer 
Signed-off-by: Sasha Levin

MIPS: Loongson64: Set timer mode in cpu-probe

2024-08-29T15:33:53+00:00

commit 1cb6ab446424649f03c82334634360c2e3043684 upstream.

Loongson64 C and G processors have EXTIMER feature which
is conflicting with CP0 counter.

Although the processor resets in EXTIMER disabled & INTIMER
enabled mode, which is compatible with MIPS CP0 compare, firmware
may attempt to enable EXTIMER and interfere CP0 compare.

Set timer mode back to MIPS compatible mode to fix booting on
systems with such firmware before we have an actual driver for
EXTIMER.

Cc: stable@vger.kernel.org
Signed-off-by: Jiaxun Yang 
Signed-off-by: Thomas Bogendoerfer 
Signed-off-by: Greg Kroah-Hartman

MIPS: Loongson: Fix cpu_probe_loongson() again

2023-07-03T14:05:51+00:00

Commit 7db5e9e9e5e6c10d7d ("MIPS: loongson64: fix FTLB configuration")
move decode_configs() from the beginning of cpu_probe_loongson() to the
end in order to fix FTLB configuration. However, it breaks the CPUCFG
decoding because decode_configs() use "c->options = xxxx" rather than
"c->options |= xxxx", all information get from CPUCFG by decode_cpucfg()
is lost.

This causes error when creating a KVM guest on Loongson-3A4000:
Exception Code: 4 not handled @ PC: 0000000087ad5981, inst: 0xcb7a1898 BadVaddr: 0x0 Status: 0x0

Fix this by moving the c->cputype setting to the beginning and moving
decode_configs() after that.

Fixes: 7db5e9e9e5e6c10d7d ("MIPS: loongson64: fix FTLB configuration")
Cc: stable@vger.kernel.org
Cc: Huang Pei 
Signed-off-by: Huacai Chen 
Signed-off-by: Thomas Bogendoerfer

MIPS: Restore Au1300 support

2023-05-23T08:59:29+00:00

The Au1300, at least the one I have to test, uses the NetLogic vendor
ID, but commit 95b8a5e0111a ("MIPS: Remove NETLOGIC support") also
dropped Au1300 detection.  Restore Au1300 detection.

Tested on DB1300 with Au1380 chip.

Signed-off-by: Manuel Lauss 
Signed-off-by: Thomas Bogendoerfer

MIPS: Octeon: Opt-out 4k_cache feature

2023-04-05T07:45:09+00:00

Octeon has a different cache interface with traditional R4K one,
just opt-out this flag for octeon to avoid run R4K cache initialization
code accidentally.

Also remove ISA level assumption for 4k cache.

Signed-off-by: Jiaxun Yang 
Signed-off-by: Thomas Bogendoerfer

MIPS: Remove VR41xx support

2022-07-14T09:52:29+00:00

No (active) developer owns this hardware, so let's remove Linux support.

Signed-off-by: Thomas Bogendoerfer

MIPS: fix typos in comments

2022-05-04T20:22:59+00:00

Various spelling mistakes in comments.
Detected with the help of Coccinelle.

Signed-off-by: Julia Lawall 
Signed-off-by: Thomas Bogendoerfer

MIPS: Remove TX39XX support

2022-03-01T09:07:22+00:00

No (active) developer owns this hardware, so let's remove Linux support.

Signed-off-by: Thomas Bogendoerfer 
Acked-by: Guenter Roeck 
Reviewed-by: Geert Uytterhoeven 
Tested-by: Geert Uytterhoeven 
Acked-by: Atsushi Nemoto

MIPS: loongson64: fix FTLB configuration

2021-11-25T15:46:31+00:00

It turns out that 'decode_configs' -> 'set_ftlb_enable' is called under
c->cputype unset, which leaves FTLB disabled on BOTH 3A2000 and 3A3000

Fix it by calling "decode_configs" after c->cputype is initialized

Fixes: da1bd29742b1 ("MIPS: Loongson64: Probe CPU features via CPUCFG")
Signed-off-by: Huang Pei 
Signed-off-by: Thomas Bogendoerfer

MIPS: Remove NETLOGIC support

2021-10-24T15:24:47+00:00

No (active) developer owns this hardware, so let's remove Linux support.

Signed-off-by: Thomas Bogendoerfer