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MIPS: cpu-probe: Avoid probing FPU when CONFIG_MIPS_FP_SUPPORT=n
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When CONFIG_MIPS_FP_SUPPORT=n we don't support floating point so there's
no point in attempting to detect an FPU. Avoid doing so.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/21021/
Cc: linux-mips@linux-mips.org
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Paul Burton committed Nov 9, 2018
1 parent 9ec5593 commit b2e628a
Showing 1 changed file with 41 additions and 13 deletions.
54 changes: 41 additions & 13 deletions arch/mips/kernel/cpu-probe.c
Original file line number Diff line number Diff line change
Expand Up @@ -36,6 +36,8 @@
unsigned int elf_hwcap __read_mostly;
EXPORT_SYMBOL_GPL(elf_hwcap);

#ifdef CONFIG_MIPS_FP_SUPPORT

/*
* Get the FPU Implementation/Revision.
*/
Expand All @@ -58,19 +60,6 @@ static inline int __cpu_has_fpu(void)
return (cpu_get_fpu_id() & FPIR_IMP_MASK) != FPIR_IMP_NONE;
}

static inline unsigned long cpu_get_msa_id(void)
{
unsigned long status, msa_id;

status = read_c0_status();
__enable_fpu(FPU_64BIT);
enable_msa();
msa_id = read_msa_ir();
disable_msa();
write_c0_status(status);
return msa_id;
}

/*
* Determine the FCSR mask for FPU hardware.
*/
Expand Down Expand Up @@ -326,6 +315,45 @@ static int __init fpu_disable(char *s)

__setup("nofpu", fpu_disable);

#else /* !CONFIG_MIPS_FP_SUPPORT */

#define mips_fpu_disabled 1

static inline unsigned long cpu_get_fpu_id(void)
{
return FPIR_IMP_NONE;
}

static inline int __cpu_has_fpu(void)
{
return 0;
}

static void cpu_set_fpu_opts(struct cpuinfo_mips *c)
{
/* no-op */
}

static void cpu_set_nofpu_opts(struct cpuinfo_mips *c)
{
/* no-op */
}

#endif /* CONFIG_MIPS_FP_SUPPORT */

static inline unsigned long cpu_get_msa_id(void)
{
unsigned long status, msa_id;

status = read_c0_status();
__enable_fpu(FPU_64BIT);
enable_msa();
msa_id = read_msa_ir();
disable_msa();
write_c0_status(status);
return msa_id;
}

static int mips_dsp_disabled;

static int __init dsp_disable(char *s)
Expand Down

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