[Qemu-devel] [PATCH v5 29/37] target-arm: Replace wildcarded cpreg definitions with precise ones for ARMv8

[Peter Maydell <peter.maydell@linaro.org>]

Many of the reginfo definitions in cp_reginfo[] use CP_ANY wildcards.
This is for a combination of reasons:
 * early ARM implementations really did underdecode
 * earlier versions of QEMU underdecoded and we can't tighten
   this up because we don't know if guests really require this or not
 * implementation convenience

For ARMv8 the architecture has tightened things up and system and
coprocessor registers are always specifically decoded. We take
advantage of this opportunity for a clean break by restricting
our CP_ANY wildcarded reginfo to pre-v8 CPUs, and providing
specifically decoded versions where necessary for v8 CPUs.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
---
 target-arm/helper.c | 96 ++++++++++++++++++++++++++++++++++++++++++++++++++---
 1 file changed, 91 insertions(+), 5 deletions(-)

diff --git a/target-arm/helper.c b/target-arm/helper.c
index 20952c3..1d1e7b4 100644
--- a/target-arm/helper.c
+++ b/target-arm/helper.c
@@ -395,11 +395,6 @@ static const ARMCPRegInfo cp_reginfo[] = {
      */
     { .name = "DBGDIDR", .cp = 14, .crn = 0, .crm = 0, .opc1 = 0, .opc2 = 0,
       .access = PL0_R, .type = ARM_CP_CONST, .resetvalue = 0 },
-    /* MMU Domain access control / MPU write buffer control */
-    { .name = "DACR", .cp = 15,
-      .crn = 3, .crm = CP_ANY, .opc1 = CP_ANY, .opc2 = CP_ANY,
-      .access = PL1_RW, .fieldoffset = offsetof(CPUARMState, cp15.c3),
-      .resetvalue = 0, .writefn = dacr_write, .raw_writefn = raw_write, },
     { .name = "FCSEIDR", .cp = 15, .crn = 13, .crm = 0, .opc1 = 0, .opc2 = 0,
       .access = PL1_RW, .fieldoffset = offsetof(CPUARMState, cp15.c13_fcse),
       .resetvalue = 0, .writefn = fcse_write, .raw_writefn = raw_write, },
@@ -408,6 +403,18 @@ static const ARMCPRegInfo cp_reginfo[] = {
       .access = PL1_RW,
       .fieldoffset = offsetof(CPUARMState, cp15.contextidr_el1),
       .resetvalue = 0, .writefn = contextidr_write, .raw_writefn = raw_write, },
+    REGINFO_SENTINEL
+};
+
+static const ARMCPRegInfo not_v8_cp_reginfo[] = {
+    /* NB: Some of these registers exist in v8 but with more precise
+     * definitions that don't use CP_ANY wildcards (mostly in v8_cp_reginfo[]).
+     */
+    /* MMU Domain access control / MPU write buffer control */
+    { .name = "DACR", .cp = 15,
+      .crn = 3, .crm = CP_ANY, .opc1 = CP_ANY, .opc2 = CP_ANY,
+      .access = PL1_RW, .fieldoffset = offsetof(CPUARMState, cp15.c3),
+      .resetvalue = 0, .writefn = dacr_write, .raw_writefn = raw_write, },
     /* ??? This covers not just the impdef TLB lockdown registers but also
      * some v7VMSA registers relating to TEX remap, so it is overly broad.
      */
@@ -1944,6 +1951,78 @@ static const ARMCPRegInfo v8_cp_reginfo[] = {
       .opc0 = 1, .opc2 = 0, .crn = 8, .crm = 7, .opc2 = 7,
       .access = PL1_W, .type = ARM_CP_NO_MIGRATE,
       .writefn = tlbi_aa64_vaa_write },
+    /* 32 bit TLB invalidates, Inner Shareable */
+    { .name = "TLBIALLIS", .cp = 15, .opc1 = 0, .crn = 8, .crm = 3, .opc2 = 0,
+      .type = ARM_CP_NO_MIGRATE, .access = PL1_W, .writefn = tlbiall_write },
+    { .name = "TLBIMVAIS", .cp = 15, .opc1 = 0, .crn = 8, .crm = 3, .opc2 = 1,
+      .type = ARM_CP_NO_MIGRATE, .access = PL1_W, .writefn = tlbimva_write },
+    { .name = "TLBIASIDIS", .cp = 15, .opc1 = 0, .crn = 8, .crm = 3, .opc2 = 2,
+      .type = ARM_CP_NO_MIGRATE, .access = PL1_W, .writefn = tlbiasid_write },
+    { .name = "TLBIMVAAIS", .cp = 15, .opc1 = 0, .crn = 8, .crm = 3, .opc2 = 3,
+      .type = ARM_CP_NO_MIGRATE, .access = PL1_W, .writefn = tlbimvaa_write },
+    { .name = "TLBIMVALIS", .cp = 15, .opc1 = 0, .crn = 8, .crm = 3, .opc2 = 5,
+      .type = ARM_CP_NO_MIGRATE, .access = PL1_W, .writefn = tlbimva_write },
+    { .name = "TLBIMVAALIS", .cp = 15, .opc1 = 0, .crn = 8, .crm = 3, .opc2 = 7,
+      .type = ARM_CP_NO_MIGRATE, .access = PL1_W, .writefn = tlbimvaa_write },
+    /* 32 bit ITLB invalidates */
+    { .name = "ITLBIALL", .cp = 15, .opc1 = 0, .crn = 8, .crm = 5, .opc2 = 0,
+      .type = ARM_CP_NO_MIGRATE, .access = PL1_W, .writefn = tlbiall_write },
+    { .name = "ITLBIMVA", .cp = 15, .opc1 = 0, .crn = 8, .crm = 5, .opc2 = 1,
+      .type = ARM_CP_NO_MIGRATE, .access = PL1_W, .writefn = tlbimva_write },
+    { .name = "ITLBIASID", .cp = 15, .opc1 = 0, .crn = 8, .crm = 5, .opc2 = 2,
+      .type = ARM_CP_NO_MIGRATE, .access = PL1_W, .writefn = tlbiasid_write },
+    /* 32 bit DTLB invalidates */
+    { .name = "DTLBIALL", .cp = 15, .opc1 = 0, .crn = 8, .crm = 6, .opc2 = 0,
+      .type = ARM_CP_NO_MIGRATE, .access = PL1_W, .writefn = tlbiall_write },
+    { .name = "DTLBIMVA", .cp = 15, .opc1 = 0, .crn = 8, .crm = 6, .opc2 = 1,
+      .type = ARM_CP_NO_MIGRATE, .access = PL1_W, .writefn = tlbimva_write },
+    { .name = "DTLBIASID", .cp = 15, .opc1 = 0, .crn = 8, .crm = 6, .opc2 = 2,
+      .type = ARM_CP_NO_MIGRATE, .access = PL1_W, .writefn = tlbiasid_write },
+    /* 32 bit TLB invalidates */
+    { .name = "TLBIALL", .cp = 15, .opc1 = 0, .crn = 8, .crm = 7, .opc2 = 0,
+      .type = ARM_CP_NO_MIGRATE, .access = PL1_W, .writefn = tlbiall_write },
+    { .name = "TLBIMVA", .cp = 15, .opc1 = 0, .crn = 8, .crm = 7, .opc2 = 1,
+      .type = ARM_CP_NO_MIGRATE, .access = PL1_W, .writefn = tlbimva_write },
+    { .name = "TLBIASID", .cp = 15, .opc1 = 0, .crn = 8, .crm = 7, .opc2 = 2,
+      .type = ARM_CP_NO_MIGRATE, .access = PL1_W, .writefn = tlbiasid_write },
+    { .name = "TLBIMVAA", .cp = 15, .opc1 = 0, .crn = 8, .crm = 7, .opc2 = 3,
+      .type = ARM_CP_NO_MIGRATE, .access = PL1_W, .writefn = tlbimvaa_write },
+    { .name = "TLBIMVAL", .cp = 15, .opc1 = 0, .crn = 8, .crm = 7, .opc2 = 5,
+      .type = ARM_CP_NO_MIGRATE, .access = PL1_W, .writefn = tlbimva_write },
+    { .name = "TLBIMVAAL", .cp = 15, .opc1 = 0, .crn = 8, .crm = 7, .opc2 = 7,
+      .type = ARM_CP_NO_MIGRATE, .access = PL1_W, .writefn = tlbimvaa_write },
+    /* 32 bit cache operations */
+    { .name = "ICIALLUIS", .cp = 15, .opc1 = 0, .crn = 7, .crm = 1, .opc2 = 0,
+      .type = ARM_CP_NOP, .access = PL1_W },
+    { .name = "BPIALLUIS", .cp = 15, .opc1 = 0, .crn = 7, .crm = 1, .opc2 = 6,
+      .type = ARM_CP_NOP, .access = PL1_W },
+    { .name = "ICIALLU", .cp = 15, .opc1 = 0, .crn = 7, .crm = 5, .opc2 = 0,
+      .type = ARM_CP_NOP, .access = PL1_W },
+    { .name = "ICIMVAU", .cp = 15, .opc1 = 0, .crn = 7, .crm = 5, .opc2 = 1,
+      .type = ARM_CP_NOP, .access = PL1_W },
+    { .name = "BPIALL", .cp = 15, .opc1 = 0, .crn = 7, .crm = 5, .opc2 = 6,
+      .type = ARM_CP_NOP, .access = PL1_W },
+    { .name = "BPIMVA", .cp = 15, .opc1 = 0, .crn = 7, .crm = 5, .opc2 = 7,
+      .type = ARM_CP_NOP, .access = PL1_W },
+    { .name = "DCIMVAC", .cp = 15, .opc1 = 0, .crn = 7, .crm = 6, .opc2 = 1,
+      .type = ARM_CP_NOP, .access = PL1_W },
+    { .name = "DCISW", .cp = 15, .opc1 = 0, .crn = 7, .crm = 6, .opc2 = 2,
+      .type = ARM_CP_NOP, .access = PL1_W },
+    { .name = "DCCMVAC", .cp = 15, .opc1 = 0, .crn = 7, .crm = 10, .opc2 = 1,
+      .type = ARM_CP_NOP, .access = PL1_W },
+    { .name = "DCCSW", .cp = 15, .opc1 = 0, .crn = 7, .crm = 10, .opc2 = 2,
+      .type = ARM_CP_NOP, .access = PL1_W },
+    { .name = "DCCMVAU", .cp = 15, .opc1 = 0, .crn = 7, .crm = 11, .opc2 = 1,
+      .type = ARM_CP_NOP, .access = PL1_W },
+    { .name = "DCCIMVAC", .cp = 15, .opc1 = 0, .crn = 7, .crm = 14, .opc2 = 1,
+      .type = ARM_CP_NOP, .access = PL1_W },
+    { .name = "DCCISW", .cp = 15, .opc1 = 0, .crn = 7, .crm = 14, .opc2 = 2,
+      .type = ARM_CP_NOP, .access = PL1_W },
+    /* MMU Domain access control / MPU write buffer control */
+    { .name = "DACR", .cp = 15,
+      .opc1 = 0, .crn = 3, .crm = 0, .opc2 = 0,
+      .access = PL1_RW, .fieldoffset = offsetof(CPUARMState, cp15.c3),
+      .resetvalue = 0, .writefn = dacr_write, .raw_writefn = raw_write, },
     /* Dummy implementation of monitor debug system control register:
      * we don't support debug.
      */
@@ -2041,6 +2120,13 @@ void register_cp_regs_for_features(ARMCPU *cpu)
     }
 
     define_arm_cp_regs(cpu, cp_reginfo);
+    if (!arm_feature(env, ARM_FEATURE_V8)) {
+        /* Must go early as it is full of wildcards that may be
+         * overridden by later definitions.
+         */
+        define_arm_cp_regs(cpu, not_v8_cp_reginfo);
+    }
+
     if (arm_feature(env, ARM_FEATURE_V6)) {
         /* The ID registers all have impdef reset values */
         ARMCPRegInfo v6_idregs[] = {
-- 
1.9.0