arm64: add pointer authentication register bits

The ARMv8.3 pointer authentication extension adds:

* New fields in ID_AA64ISAR1 to report the presence of pointer
  authentication functionality.

* New control bits in SCTLR_ELx to enable this functionality.

* New system registers to hold the keys necessary for this
  functionality.

* A new ESR_ELx.EC code used when the new instructions are affected by
  configurable traps

This patch adds the relevant definitions to <asm/sysreg.h> and
<asm/esr.h> for these, to be used by subsequent patches.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

arch/arm64/include/asm/esr.h

@@ -30,7 +30,8 @@
 #define ESR_ELx_EC_CP14_LS	(0x06)
 #define ESR_ELx_EC_FP_ASIMD	(0x07)
 #define ESR_ELx_EC_CP10_ID	(0x08)	/* EL2 only */
-/* Unallocated EC: 0x09 - 0x0B */
+#define ESR_ELx_EC_PAC		(0x09)	/* EL2 and above */
+/* Unallocated EC: 0x0A - 0x0B */
 #define ESR_ELx_EC_CP14_64	(0x0C)
 /* Unallocated EC: 0x0d */
 #define ESR_ELx_EC_ILL		(0x0E)

arch/arm64/include/asm/sysreg.h

@@ -188,6 +188,19 @@
 #define SYS_TTBR1_EL1			sys_reg(3, 0, 2, 0, 1)
 #define SYS_TCR_EL1			sys_reg(3, 0, 2, 0, 2)
 
+#define SYS_APIAKEYLO_EL1		sys_reg(3, 0, 2, 1, 0)
+#define SYS_APIAKEYHI_EL1		sys_reg(3, 0, 2, 1, 1)
+#define SYS_APIBKEYLO_EL1		sys_reg(3, 0, 2, 1, 2)
+#define SYS_APIBKEYHI_EL1		sys_reg(3, 0, 2, 1, 3)
+
+#define SYS_APDAKEYLO_EL1		sys_reg(3, 0, 2, 2, 0)
+#define SYS_APDAKEYHI_EL1		sys_reg(3, 0, 2, 2, 1)
+#define SYS_APDBKEYLO_EL1		sys_reg(3, 0, 2, 2, 2)
+#define SYS_APDBKEYHI_EL1		sys_reg(3, 0, 2, 2, 3)
+
+#define SYS_APGAKEYLO_EL1		sys_reg(3, 0, 2, 3, 0)
+#define SYS_APGAKEYHI_EL1		sys_reg(3, 0, 2, 3, 1)
+
 #define SYS_ICC_PMR_EL1			sys_reg(3, 0, 4, 6, 0)
 
 #define SYS_AFSR0_EL1			sys_reg(3, 0, 5, 1, 0)
@@ -437,9 +450,13 @@
 
 /* Common SCTLR_ELx flags. */
 #define SCTLR_ELx_DSSBS	(1UL << 44)
+#define SCTLR_ELx_ENIA	(1U << 31)
+#define SCTLR_ELx_ENIB	(1 << 30)
+#define SCTLR_ELx_ENDA	(1 << 27)
 #define SCTLR_ELx_EE    (1 << 25)
 #define SCTLR_ELx_IESB	(1 << 21)
 #define SCTLR_ELx_WXN	(1 << 19)
+#define SCTLR_ELx_ENDB	(1 << 13)
 #define SCTLR_ELx_I	(1 << 12)
 #define SCTLR_ELx_SA	(1 << 3)
 #define SCTLR_ELx_C	(1 << 2)
@@ -534,11 +551,24 @@
 
 /* id_aa64isar1 */
 #define ID_AA64ISAR1_SB_SHIFT		36
+#define ID_AA64ISAR1_GPI_SHIFT		28
+#define ID_AA64ISAR1_GPA_SHIFT		24
 #define ID_AA64ISAR1_LRCPC_SHIFT	20
 #define ID_AA64ISAR1_FCMA_SHIFT		16
 #define ID_AA64ISAR1_JSCVT_SHIFT	12
+#define ID_AA64ISAR1_API_SHIFT		8
+#define ID_AA64ISAR1_APA_SHIFT		4
 #define ID_AA64ISAR1_DPB_SHIFT		0
 
+#define ID_AA64ISAR1_APA_NI		0x0
+#define ID_AA64ISAR1_APA_ARCHITECTED	0x1
+#define ID_AA64ISAR1_API_NI		0x0
+#define ID_AA64ISAR1_API_IMP_DEF	0x1
+#define ID_AA64ISAR1_GPA_NI		0x0
+#define ID_AA64ISAR1_GPA_ARCHITECTED	0x1
+#define ID_AA64ISAR1_GPI_NI		0x0
+#define ID_AA64ISAR1_GPI_IMP_DEF	0x1
+
 /* id_aa64pfr0 */
 #define ID_AA64PFR0_CSV3_SHIFT		60
 #define ID_AA64PFR0_CSV2_SHIFT		56