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charset=us-ascii Content-Disposition: inline In-Reply-To: <11d99a7c-50f9-4a4d-a75b-ef11cf3371af@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260714_070106_473790_79FEFA36 X-CRM114-Status: GOOD ( 24.23 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi, On Fri, Jul 10, 2026 at 12:41:57PM +0530, Anshuman Khandual wrote: > Please do mention full register field here > > arm64: cpufeature: Detect BBML3 based on ID_AA64MMFR2_EL1.BBM > > On 08/07/26 8:13 PM, Linu Cherian wrote: > > Add MMFR2 ID based BBML3 feature detection, so > > Ditto ^^^^^^^^^^^^ > > > that compliant cpus doesn't need to be added to the > > midr list. > > Could be reworded as : > > Add ID_AA64MMFR2_EL1.BBM based BBML3 feature detection in > cpu_supports_bbml3() so that cpus with the feature would > not have to be added into MIDR based supports_bbml3_list. > Okay, will change. > > > > Signed-off-by: Linu Cherian > > --- > > arch/arm64/kernel/cpufeature.c | 17 +++++++++-------- > > 1 file changed, 9 insertions(+), 8 deletions(-) > > > > diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c > > index e9ecaa036479..3f4a36f152d0 100644 > > --- a/arch/arm64/kernel/cpufeature.c > > +++ b/arch/arm64/kernel/cpufeature.c > > @@ -2133,6 +2133,12 @@ static bool hvhe_possible(const struct arm64_cpu_capabilities *entry, > > > > bool cpu_supports_bbml3(void) > > { > > + u64 mmfr2; > > + > > + mmfr2 = __read_sysreg_by_encoding(SYS_ID_AA64MMFR2_EL1); > > + if (SYS_FIELD_GET(ID_AA64MMFR2_EL1, BBM, mmfr2) >= ID_AA64MMFR2_EL1_BBM_3) > > + return true; > > + > > /* CPUs that support BBML3 but dont advertise through MMFR2 ID */ > > static const struct midr_range supports_bbml3_list[] = { > > MIDR_REV_RANGE(MIDR_CORTEX_X4, 0, 3, 0xf), > > @@ -2153,15 +2159,10 @@ bool cpu_supports_bbml3(void) > > {} > > }; > > > > - if (!is_midr_in_range_list(supports_bbml3_list)) > > - return false; > > - > > - /* > > - * We currently ignore the ID_AA64MMFR2_EL1 register, and only care > > - * about whether the MIDR check passes. > > - */ > > + if (is_midr_in_range_list(supports_bbml3_list)) > > + return true; > > > > - return true; > > + return false; > > } > > > > static bool has_bbml3(const struct arm64_cpu_capabilities *caps, int scope) > > With the minor changes to the commit message above. > > Reviewed-by: Anshuman Khandual