arm/cpu: Add sysreg definitions in cpu-sysregs.h

This new header contains macros that define aarch64 registers.
In a subsequent patch, this will be replaced by a more exhaustive
version that will be generated from linux arch/arm64/tools/sysreg
file. Those macros are sufficient to migrate the storage of those
ID regs from named fields in isar struct to an array cell.

[CH: reworked to use different structures]
[CH: moved accessors from the patches first using them to here,
     dropped interaction with writable registers, which will happen
     later]
[CH: use DEF magic suggested by rth]
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Sebastian Ott <sebott@redhat.com>
Signed-off-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Message-id: 20250617153931.1330449-2-cohuck@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

4 files changed, 149 insertions, 0 deletions

diff --git a/target/arm/cpu-sysregs.h b/target/arm/cpu-sysregs.h
new file mode 100644
index 0000000..7877a3b
--- /dev/null
+++ b/target/arm/cpu-sysregs.h
@@ -0,0 +1,42 @@
+/*
+ * Definitions for Arm ID system registers
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+#ifndef ARM_CPU_SYSREGS_H
+#define ARM_CPU_SYSREGS_H
+
+/*
+ * Following is similar to the coprocessor regs encodings, but with an argument
+ * ordering that matches the ARM ARM. We also reuse the various CP_REG_ defines
+ * that actually are the same as the equivalent KVM_REG_ values.
+ */
+#define ENCODE_ID_REG(op0, op1, crn, crm, op2)          \
+    (((op0) << CP_REG_ARM64_SYSREG_OP0_SHIFT) |         \
+     ((op1) << CP_REG_ARM64_SYSREG_OP1_SHIFT) |         \
+     ((crn) << CP_REG_ARM64_SYSREG_CRN_SHIFT) |         \
+     ((crm) << CP_REG_ARM64_SYSREG_CRM_SHIFT) |         \
+     ((op2) << CP_REG_ARM64_SYSREG_OP2_SHIFT))
+
+#define DEF(NAME, OP0, OP1, CRN, CRM, OP2) NAME##_IDX,
+
+typedef enum ARMIDRegisterIdx {
+#include "cpu-sysregs.h.inc"
+    NUM_ID_IDX,
+} ARMIDRegisterIdx;
+
+#undef DEF
+#define DEF(NAME, OP0, OP1, CRN, CRM, OP2) \
+    SYS_##NAME = ENCODE_ID_REG(OP0, OP1, CRN, CRM, OP2),
+
+typedef enum ARMSysRegs {
+#include "cpu-sysregs.h.inc"
+} ARMSysRegs;
+
+#undef DEF
+
+extern const uint32_t id_register_sysreg[NUM_ID_IDX];
+
+int get_sysreg_idx(ARMSysRegs sysreg);
+
+#endif /* ARM_CPU_SYSREGS_H */
diff --git a/target/arm/cpu-sysregs.h.inc b/target/arm/cpu-sysregs.h.inc
new file mode 100644
index 0000000..cb99286
--- /dev/null
+++ b/target/arm/cpu-sysregs.h.inc
@@ -0,0 +1,36 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+DEF(ID_AA64PFR0_EL1, 3, 0, 0, 4, 0)
+DEF(ID_AA64PFR1_EL1, 3, 0, 0, 4, 1)
+DEF(ID_AA64SMFR0_EL1, 3, 0, 0, 4, 5)
+DEF(ID_AA64DFR0_EL1, 3, 0, 0, 5, 0)
+DEF(ID_AA64DFR1_EL1, 3, 0, 0, 5, 1)
+DEF(ID_AA64ISAR0_EL1, 3, 0, 0, 6, 0)
+DEF(ID_AA64ISAR1_EL1, 3, 0, 0, 6, 1)
+DEF(ID_AA64ISAR2_EL1, 3, 0, 0, 6, 2)
+DEF(ID_AA64MMFR0_EL1, 3, 0, 0, 7, 0)
+DEF(ID_AA64MMFR1_EL1, 3, 0, 0, 7, 1)
+DEF(ID_AA64MMFR2_EL1, 3, 0, 0, 7, 2)
+DEF(ID_AA64MMFR3_EL1, 3, 0, 0, 7, 3)
+DEF(ID_PFR0_EL1, 3, 0, 0, 1, 0)
+DEF(ID_PFR1_EL1, 3, 0, 0, 1, 1)
+DEF(ID_DFR0_EL1, 3, 0, 0, 1, 2)
+DEF(ID_MMFR0_EL1, 3, 0, 0, 1, 4)
+DEF(ID_MMFR1_EL1, 3, 0, 0, 1, 5)
+DEF(ID_MMFR2_EL1, 3, 0, 0, 1, 6)
+DEF(ID_MMFR3_EL1, 3, 0, 0, 1, 7)
+DEF(ID_ISAR0_EL1, 3, 0, 0, 2, 0)
+DEF(ID_ISAR1_EL1, 3, 0, 0, 2, 1)
+DEF(ID_ISAR2_EL1, 3, 0, 0, 2, 2)
+DEF(ID_ISAR3_EL1, 3, 0, 0, 2, 3)
+DEF(ID_ISAR4_EL1, 3, 0, 0, 2, 4)
+DEF(ID_ISAR5_EL1, 3, 0, 0, 2, 5)
+DEF(ID_MMFR4_EL1, 3, 0, 0, 2, 6)
+DEF(ID_ISAR6_EL1, 3, 0, 0, 2, 7)
+DEF(MVFR0_EL1, 3, 0, 0, 3, 0)
+DEF(MVFR1_EL1, 3, 0, 0, 3, 1)
+DEF(MVFR2_EL1, 3, 0, 0, 3, 2)
+DEF(ID_PFR2_EL1, 3, 0, 0, 3, 4)
+DEF(ID_DFR1_EL1, 3, 0, 0, 3, 5)
+DEF(ID_MMFR5_EL1, 3, 0, 0, 3, 6)
+DEF(ID_AA64ZFR0_EL1, 3, 0, 0, 4, 4)
+DEF(CTR_EL0, 3, 3, 0, 0, 1)
diff --git a/target/arm/cpu.h b/target/arm/cpu.h
index 302c24e..45409f8 100644
--- a/target/arm/cpu.h
+++ b/target/arm/cpu.h
@@ -32,6 +32,7 @@
 #include "qapi/qapi-types-common.h"
 #include "target/arm/multiprocessing.h"
 #include "target/arm/gtimer.h"
+#include "target/arm/cpu-sysregs.h"
 
 #define EXCP_UDEF            1   /* undefined instruction */
 #define EXCP_SWI             2   /* software interrupt */
@@ -834,6 +835,53 @@ typedef struct {
     uint32_t map, init, supported;
 } ARMVQMap;
 
+/* REG is ID_XXX */
+#define FIELD_DP64_IDREG(ISAR, REG, FIELD, VALUE)                       \
+    ({                                                                  \
+        ARMISARegisters *i_ = (ISAR);                                   \
+        uint64_t regval = i_->idregs[REG ## _EL1_IDX];                  \
+        regval = FIELD_DP64(regval, REG, FIELD, VALUE);                 \
+        i_->idregs[REG ## _EL1_IDX] = regval;                           \
+    })
+
+#define FIELD_DP32_IDREG(ISAR, REG, FIELD, VALUE)                       \
+    ({                                                                  \
+        ARMISARegisters *i_ = (ISAR);                                   \
+        uint64_t regval = i_->idregs[REG ## _EL1_IDX];                  \
+        regval = FIELD_DP32(regval, REG, FIELD, VALUE);                 \
+        i_->idregs[REG ## _EL1_IDX] = regval;                           \
+    })
+
+#define FIELD_EX64_IDREG(ISAR, REG, FIELD)                              \
+    ({                                                                  \
+        const ARMISARegisters *i_ = (ISAR);                             \
+        FIELD_EX64(i_->idregs[REG ## _EL1_IDX], REG, FIELD);            \
+    })
+
+#define FIELD_EX32_IDREG(ISAR, REG, FIELD)                              \
+    ({                                                                  \
+        const ARMISARegisters *i_ = (ISAR);                             \
+        FIELD_EX32(i_->idregs[REG ## _EL1_IDX], REG, FIELD);            \
+    })
+
+#define FIELD_SEX64_IDREG(ISAR, REG, FIELD)                             \
+    ({                                                                  \
+        const ARMISARegisters *i_ = (ISAR);                             \
+        FIELD_SEX64(i_->idregs[REG ## _EL1_IDX], REG, FIELD);           \
+    })
+
+#define SET_IDREG(ISAR, REG, VALUE)                                     \
+    ({                                                                  \
+        ARMISARegisters *i_ = (ISAR);                                   \
+        i_->idregs[REG ## _EL1_IDX] = VALUE;                            \
+    })
+
+#define GET_IDREG(ISAR, REG)                                            \
+    ({                                                                  \
+        const ARMISARegisters *i_ = (ISAR);                             \
+        i_->idregs[REG ## _EL1_IDX];                                    \
+    })
+
 /**
  * ARMCPU:
  * @env: #CPUARMState
@@ -1040,6 +1088,7 @@ struct ArchCPU {
         uint64_t id_aa64zfr0;
         uint64_t id_aa64smfr0;
         uint64_t reset_pmcr_el0;
+        uint64_t idregs[NUM_ID_IDX];
     } isar;
     uint64_t midr;
     uint32_t revidr;
diff --git a/target/arm/cpu64.c b/target/arm/cpu64.c
index 200da1c..77054e0 100644
--- a/target/arm/cpu64.c
+++ b/target/arm/cpu64.c
@@ -36,6 +36,28 @@
 #include "cpu-features.h"
 #include "cpregs.h"
 
+/* convert between <register>_IDX and SYS_<register> */
+#define DEF(NAME, OP0, OP1, CRN, CRM, OP2)      \
+    [NAME##_IDX] = SYS_##NAME,
+
+const uint32_t id_register_sysreg[NUM_ID_IDX] = {
+#include "cpu-sysregs.h.inc"
+};
+
+#undef DEF
+#define DEF(NAME, OP0, OP1, CRN, CRM, OP2) \
+    case SYS_##NAME: return NAME##_IDX;
+
+int get_sysreg_idx(ARMSysRegs sysreg)
+{
+    switch (sysreg) {
+#include "cpu-sysregs.h.inc"
+    }
+    g_assert_not_reached();
+}
+
+#undef DEF
+
 void arm_cpu_sve_finalize(ARMCPU *cpu, Error **errp)
 {
     /*