[PATCH 5/5] arm64: Remove CONFIG_ARM64_CNP

[Marc Zyngier]

Now that all the users of CnP are gone, let's perform a final
cleanup by removing the Kconfig entry, the CPU feature, and
the system_supports_cnp() helper.

The only traces left of CnP are ID register definitions, the feature
detection, and the bit definitions. All of which serve as documentation
and can be safely kept.

Signed-off-by: Marc Zyngier <maz at kernel.org>
---
 arch/arm64/Kconfig                  | 14 --------------
 arch/arm64/include/asm/cpufeature.h |  6 ------
 arch/arm64/tools/cpucaps            |  1 -
 3 files changed, 21 deletions(-)

diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 41125ff8ae69..02318ad49a6f 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -1818,20 +1818,6 @@ config ARM64_RAS_EXTN
 	  and access the new registers if the system supports the extension.
 	  Platform RAS features may additionally depend on firmware support.
 
-config ARM64_CNP
-	bool "Enable support for Common Not Private (CNP) translations"
-	default y
-	depends on ARM64_PAN || !ARM64_SW_TTBR0_PAN
-	help
-	  Common Not Private (CNP) allows translation table entries to
-	  be shared between different PEs in the same inner shareable
-	  domain, so the hardware can use this fact to optimise the
-	  caching of such entries in the TLB.
-
-	  Selecting this option allows the CNP feature to be detected
-	  at runtime, and does not affect PEs that do not implement
-	  this feature.
-
 endmenu # "ARMv8.2 architectural features"
 
 menu "ARMv8.3 architectural features"
diff --git a/arch/arm64/include/asm/cpufeature.h b/arch/arm64/include/asm/cpufeature.h
index 6bf013fb110d..172f3d01ef9b 100644
--- a/arch/arm64/include/asm/cpufeature.h
+++ b/arch/arm64/include/asm/cpufeature.h
@@ -786,12 +786,6 @@ static __always_inline bool system_supports_tpidr2(void)
 	return system_supports_sme();
 }
 
-static __always_inline bool system_supports_cnp(void)
-{
-	return IS_ENABLED(CONFIG_ARM64_CNP) &&
-		cpus_have_const_cap(ARM64_HAS_CNP);
-}
-
 static inline bool system_supports_address_auth(void)
 {
 	return IS_ENABLED(CONFIG_ARM64_PTR_AUTH) &&
diff --git a/arch/arm64/tools/cpucaps b/arch/arm64/tools/cpucaps
index a94808ba819c..b5111f76bc72 100644
--- a/arch/arm64/tools/cpucaps
+++ b/arch/arm64/tools/cpucaps
@@ -16,7 +16,6 @@ HAS_AMU_EXTN
 HAS_ARMv8_4_TTL
 HAS_CACHE_DIC
 HAS_CACHE_IDC
-HAS_CNP
 HAS_CRC32
 HAS_DCPODP
 HAS_DCPOP
-- 
2.39.2