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| author | Huacai Chen <chenhc@lemote.com> | 2020-09-21 17:12:27 +0800 |
|---|---|---|
| committer | Thomas Bogendoerfer <tsbogend@alpha.franken.de> | 2020-09-21 22:15:03 +0200 |
| commit | 195615ecc8309082a524433cf552eda722b26c1c (patch) | |
| tree | 08d25c30f8af71ab927275237f96e6fdd4b0abfe /arch/mips/include/asm/stackframe.h | |
| parent | 4e43e5df5850ca8300180f422727e42a5065aaaa (diff) | |
| download | linux-195615ecc8309082a524433cf552eda722b26c1c.tar.gz linux-195615ecc8309082a524433cf552eda722b26c1c.tar.bz2 linux-195615ecc8309082a524433cf552eda722b26c1c.zip | |
MIPS: Loongson-3: Enable COP2 usage in kernel
Loongson-3's COP2 is Multi-Media coprocessor, it is disabled in kernel
mode by default. However, gslq/gssq (16-bytes load/store instructions)
overrides the instruction format of lwc2/swc2. If we wan't to use gslq/
gssq for optimization in kernel, we should enable COP2 usage in kernel.
Please pay attention that in this patch we only enable COP2 in kernel,
which means it will lose ST0_CU2 when a process go to user space (try
to use COP2 in user space will trigger an exception and then grab COP2,
which is similar to FPU). And as a result, we need to modify the context
switching code because the new scheduled process doesn't contain ST0_CU2
in its THERAD_STATUS probably.
For zboot, we disable gslq/gssq be generated by toolchain.
Signed-off-by: Huacai Chen <chenhc@lemote.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Diffstat (limited to 'arch/mips/include/asm/stackframe.h')
| -rw-r--r-- | arch/mips/include/asm/stackframe.h | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/arch/mips/include/asm/stackframe.h b/arch/mips/include/asm/stackframe.h index 3e8d2aaf96af..aa430a6c68b2 100644 --- a/arch/mips/include/asm/stackframe.h +++ b/arch/mips/include/asm/stackframe.h @@ -450,7 +450,7 @@ */ .macro CLI mfc0 t0, CP0_STATUS - li t1, ST0_CU0 | STATMASK + li t1, ST0_KERNEL_CUMASK | STATMASK or t0, t1 xori t0, STATMASK mtc0 t0, CP0_STATUS @@ -463,7 +463,7 @@ */ .macro STI mfc0 t0, CP0_STATUS - li t1, ST0_CU0 | STATMASK + li t1, ST0_KERNEL_CUMASK | STATMASK or t0, t1 xori t0, STATMASK & ~1 mtc0 t0, CP0_STATUS @@ -477,7 +477,7 @@ */ .macro KMODE mfc0 t0, CP0_STATUS - li t1, ST0_CU0 | (STATMASK & ~1) + li t1, ST0_KERNEL_CUMASK | (STATMASK & ~1) #if defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX) andi t2, t0, ST0_IEP srl t2, 2 |