The commit d5370f754875 ("arm64: prefetch: add alternative pattern for
CPUs without a prefetcher") introduced MIDR_IS_CPU_MODEL_RANGE() to be
used in has_no_hw_prefetch() with rv_min=0 which generates a compilation
warning from GCC,

In file included from ./arch/arm64/include/asm/cache.h:8,
               from ./include/linux/cache.h:6,
               from ./include/linux/printk.h:9,
               from ./include/linux/kernel.h:15,
               from ./include/linux/cpumask.h:10,
               from arch/arm64/kernel/cpufeature.c:11:
arch/arm64/kernel/cpufeature.c: In function 'has_no_hw_prefetch':
./arch/arm64/include/asm/cputype.h:59:26: warning: comparison of
unsigned expression >= 0 is always true [-Wtype-limits]
_model == (model) && rv >= (rv_min) && rv <= (rv_max);  \
                        ^~
arch/arm64/kernel/cpufeature.c:889:9: note: in expansion of macro
'MIDR_IS_CPU_MODEL_RANGE'
return MIDR_IS_CPU_MODEL_RANGE(midr, MIDR_THUNDERX,
       ^~~~~~~~~~~~~~~~~~~~~~~

Fix it by converting MIDR_IS_CPU_MODEL_RANGE to a static inline
function.

Signed-off-by: Qian Cai <c...@lca.pw>
---

v3: Convert MIDR_IS_CPU_MODEL_RANGE to a static inline function.
v2: Use "s32" for "rv", so "variant 0/revision 0" can be covered.

 arch/arm64/include/asm/cputype.h | 21 +++++++++++----------
 arch/arm64/kernel/cpufeature.c   |  2 +-
 2 files changed, 12 insertions(+), 11 deletions(-)

diff --git a/arch/arm64/include/asm/cputype.h b/arch/arm64/include/asm/cputype.h
index e7d46631cc42..b1454d117cd2 100644
--- a/arch/arm64/include/asm/cputype.h
+++ b/arch/arm64/include/asm/cputype.h
@@ -51,14 +51,6 @@
 #define MIDR_CPU_MODEL_MASK (MIDR_IMPLEMENTOR_MASK | MIDR_PARTNUM_MASK | \
                             MIDR_ARCHITECTURE_MASK)
 
-#define MIDR_IS_CPU_MODEL_RANGE(midr, model, rv_min, rv_max)           \
-({                                                                     \
-       u32 _model = (midr) & MIDR_CPU_MODEL_MASK;                      \
-       u32 rv = (midr) & (MIDR_REVISION_MASK | MIDR_VARIANT_MASK);     \
-                                                                       \
-       _model == (model) && rv >= (rv_min) && rv <= (rv_max);          \
- })
-
 #define ARM_CPU_IMP_ARM                        0x41
 #define ARM_CPU_IMP_APM                        0x50
 #define ARM_CPU_IMP_CAVIUM             0x43
@@ -159,10 +151,19 @@ struct midr_range {
 #define MIDR_REV(m, v, r) MIDR_RANGE(m, v, r, v, r)
 #define MIDR_ALL_VERSIONS(m) MIDR_RANGE(m, 0, 0, 0xf, 0xf)
 
+static inline bool midr_is_cpu_model_range(u32 midr, u32 model, u32 rv_min,
+                                          u32 rv_max)
+{
+       u32 _model = midr & MIDR_CPU_MODEL_MASK;
+       u32 rv = midr & (MIDR_REVISION_MASK | MIDR_VARIANT_MASK);
+
+       return _model == model && rv >= rv_min && rv <= rv_max;
+}
+
 static inline bool is_midr_in_range(u32 midr, struct midr_range const *range)
 {
-       return MIDR_IS_CPU_MODEL_RANGE(midr, range->model,
-                                range->rv_min, range->rv_max);
+       return midr_is_cpu_model_range(midr, range->model,
+                                      range->rv_min, range->rv_max);
 }
 
 static inline bool
diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index d19d14ba9ae4..95201e5ff5e1 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -886,7 +886,7 @@ static bool has_no_hw_prefetch(const struct 
arm64_cpu_capabilities *entry, int _
        u32 midr = read_cpuid_id();
 
        /* Cavium ThunderX pass 1.x and 2.x */
-       return MIDR_IS_CPU_MODEL_RANGE(midr, MIDR_THUNDERX,
+       return midr_is_cpu_model_range(midr, MIDR_THUNDERX,
                MIDR_CPU_VAR_REV(0, 0),
                MIDR_CPU_VAR_REV(1, MIDR_REVISION_MASK));
 }
-- 
2.20.1 (Apple Git-117)

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