[RFC 04/10] arm64/mm: Add FEAT_LPA2 specific ID_AA64MMFR0.TGRAN[2]

Anshuman Khandual anshuman.khandual at arm.com
Tue Jul 13 19:21:25 PDT 2021


PAGE_SIZE support is tested against possible minimum and maximum values for
its respective ID_AA64MMFR0.TGRAN field, depending on whether it is signed
or unsigned. But then FEAT_LPA2 implementation needs to be validated for 4K
and 16K page sizes via feature specific ID_AA64MMFR0.TGRAN values. Hence it
adds FEAT_LPA2 specific ID_AA64MMFR0.TGRAN[2] values per ARM ARM (0487G.A).

Signed-off-by: Anshuman Khandual <anshuman.khandual at arm.com>
---
 arch/arm64/include/asm/sysreg.h | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h
index 5cbfaf6..deecde0 100644
--- a/arch/arm64/include/asm/sysreg.h
+++ b/arch/arm64/include/asm/sysreg.h
@@ -849,16 +849,19 @@
 
 #define ID_AA64MMFR0_TGRAN4_NI		0xf
 #define ID_AA64MMFR0_TGRAN4_SUPPORTED	0x0
+#define ID_AA64MMFR0_TGRAN4_LPA2	0x1
 #define ID_AA64MMFR0_TGRAN64_NI		0xf
 #define ID_AA64MMFR0_TGRAN64_SUPPORTED	0x0
 #define ID_AA64MMFR0_TGRAN16_NI		0x0
 #define ID_AA64MMFR0_TGRAN16_SUPPORTED	0x1
+#define ID_AA64MMFR0_TGRAN16_LPA2	0x2
 #define ID_AA64MMFR0_PARANGE_48		0x5
 #define ID_AA64MMFR0_PARANGE_52		0x6
 
 #define ID_AA64MMFR0_TGRAN_2_SUPPORTED_DEFAULT	0x0
 #define ID_AA64MMFR0_TGRAN_2_SUPPORTED_NONE	0x1
 #define ID_AA64MMFR0_TGRAN_2_SUPPORTED_MIN	0x2
+#define ID_AA64MMFR0_TGRAN_2_SUPPORTED_LPA2	0x3
 #define ID_AA64MMFR0_TGRAN_2_SUPPORTED_MAX	0x7
 
 #ifdef CONFIG_ARM64_PA_BITS_52
@@ -1030,10 +1033,12 @@
 #define ID_AA64MMFR0_TGRAN_SHIFT		ID_AA64MMFR0_TGRAN4_SHIFT
 #define ID_AA64MMFR0_TGRAN_SUPPORTED_MIN	ID_AA64MMFR0_TGRAN4_SUPPORTED
 #define ID_AA64MMFR0_TGRAN_SUPPORTED_MAX	0x7
+#define ID_AA64MMFR0_TGRAN_LPA2			ID_AA64MMFR0_TGRAN4_LPA2
 #elif defined(CONFIG_ARM64_16K_PAGES)
 #define ID_AA64MMFR0_TGRAN_SHIFT		ID_AA64MMFR0_TGRAN16_SHIFT
 #define ID_AA64MMFR0_TGRAN_SUPPORTED_MIN	ID_AA64MMFR0_TGRAN16_SUPPORTED
 #define ID_AA64MMFR0_TGRAN_SUPPORTED_MAX	0xF
+#define ID_AA64MMFR0_TGRAN_LPA2			ID_AA64MMFR0_TGRAN16_LPA2
 #elif defined(CONFIG_ARM64_64K_PAGES)
 #define ID_AA64MMFR0_TGRAN_SHIFT		ID_AA64MMFR0_TGRAN64_SHIFT
 #define ID_AA64MMFR0_TGRAN_SUPPORTED_MIN	ID_AA64MMFR0_TGRAN64_SUPPORTED
-- 
2.7.4




More information about the linux-arm-kernel mailing list