arm64/prefetch: fix a -Wtype-limits warning

BugLink: https://bugs.launchpad.net/bugs/1848046
[ Upstream commit b99286b088ea843b935dcfb29f187697359fe5cd ]

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 <cai@lca.pw>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>
Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>

diff --git a/arch/arm64/include/asm/cputype.h b/arch/arm64/include/asm/cputype.h
index e7d46631cc42ba1bd18adf6a279a2c1f74575e85..b1454d117cd2c69582d519f123fcaa66f5f81c44 100644 (file)
--- 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 b1fdc486aed8239c681acdcab1d98550bbdf60d9..9323bcc40a58a7c34d2ec502c35fad4633a5d118 100644 (file)
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -894,7 +894,7 @@ 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));
 }