[Qemu-devel] [PATCH v4 19/33] target-arm: insert Aarch32 cpregs twice into hashtable

[greg.bellows@linaro.org]

From: Fabian Aggeler <aggelerf@ethz.ch>

Prepare for cp register banking by inserting every cp register twice,
once for secure world and once for non-secure world.

Signed-off-by: Fabian Aggeler <aggelerf@ethz.ch>
Signed-off-by: Greg Bellows <greg.bellows@linaro.org>
---
 target-arm/cpu.h       | 14 +++++++++++---
 target-arm/helper.c    | 20 ++++++++++++++++----
 target-arm/translate.c | 19 +++++++++++++------
 3 files changed, 40 insertions(+), 13 deletions(-)

diff --git a/target-arm/cpu.h b/target-arm/cpu.h
index baf6281..76fd7f3 100644
--- a/target-arm/cpu.h
+++ b/target-arm/cpu.h
@@ -847,6 +847,7 @@ void armv7m_nvic_complete_irq(void *opaque, int irq);
  *  Crn, Crm, opc1, opc2 fields
  *  32 or 64 bit register (ie is it accessed via MRC/MCR
  *    or via MRRC/MCRR?)
+ *  non-secure/secure bank (Aarch32 only)
  * We allow 4 bits for opc1 because MRRC/MCRR have a 4 bit field.
  * (In this case crn and opc2 should be zero.)
  * For AArch64, there is no 32/64 bit size distinction;
@@ -864,9 +865,16 @@ void armv7m_nvic_complete_irq(void *opaque, int irq);
 #define CP_REG_AA64_SHIFT 28
 #define CP_REG_AA64_MASK (1 << CP_REG_AA64_SHIFT)
 
-#define ENCODE_CP_REG(cp, is64, crn, crm, opc1, opc2)   \
-    (((cp) << 16) | ((is64) << 15) | ((crn) << 11) |    \
-     ((crm) << 7) | ((opc1) << 3) | (opc2))
+/* To enable banking of coprocessor registers depending on ns-bit we
+ * add a bit to distinguish between secure and non-secure cpregs in the
+ * hashtable.
+ */
+#define CP_REG_NS_SHIFT 27
+#define CP_REG_NS_MASK(nsbit) (nsbit << CP_REG_NS_SHIFT)
+
+#define ENCODE_CP_REG(cp, is64, crn, crm, opc1, opc2, ns)   \
+    (CP_REG_NS_MASK(ns) | ((cp) << 16) | ((is64) << 15) |   \
+     ((crn) << 11) | ((crm) << 7) | ((opc1) << 3) | (opc2))
 
 #define ENCODE_AA64_CP_REG(cp, crn, crm, op0, op1, op2) \
     (CP_REG_AA64_MASK |                                 \
diff --git a/target-arm/helper.c b/target-arm/helper.c
index d3dbf33..5d011fd 100644
--- a/target-arm/helper.c
+++ b/target-arm/helper.c
@@ -2898,7 +2898,7 @@ CpuDefinitionInfoList *arch_query_cpu_definitions(Error **errp)
 
 static void add_cpreg_to_hashtable(ARMCPU *cpu, const ARMCPRegInfo *r,
                                    void *opaque, int state,
-                                   int crm, int opc1, int opc2)
+                                   int crm, int opc1, int opc2, int nsbit)
 {
     /* Private utility function for define_one_arm_cp_reg_with_opaque():
      * add a single reginfo struct to the hash table.
@@ -2932,7 +2932,7 @@ static void add_cpreg_to_hashtable(ARMCPU *cpu, const ARMCPRegInfo *r,
         *key = ENCODE_AA64_CP_REG(r2->cp, r2->crn, crm,
                                   r2->opc0, opc1, opc2);
     } else {
-        *key = ENCODE_CP_REG(r2->cp, is64, r2->crn, crm, opc1, opc2);
+        *key = ENCODE_CP_REG(r2->cp, is64, r2->crn, crm, opc1, opc2, nsbit);
     }
     if (opaque) {
         r2->opaque = opaque;
@@ -3081,8 +3081,20 @@ void define_one_arm_cp_reg_with_opaque(ARMCPU *cpu,
                     if (r->state != state && r->state != ARM_CP_STATE_BOTH) {
                         continue;
                     }
-                    add_cpreg_to_hashtable(cpu, r, opaque, state,
-                                           crm, opc1, opc2);
+                    if (state == ARM_CP_STATE_AA32) {
+                        /* Under Aarch32 CP registers can be common
+                         * (same for secure and non-secure world) or banked.
+                         */
+                        add_cpreg_to_hashtable(cpu, r, opaque, state,
+                                crm, opc1, opc2, !SCR_NS);
+                        add_cpreg_to_hashtable(cpu, r, opaque, state,
+                                crm, opc1, opc2, SCR_NS);
+                    } else {
+                        /* Aarch64 registers get mapped to non-secure instance
+                         * of Aarch32 */
+                        add_cpreg_to_hashtable(cpu, r, opaque, state,
+                                crm, opc1, opc2, SCR_NS);
+                    }
                 }
             }
         }
diff --git a/target-arm/translate.c b/target-arm/translate.c
index f657389..30d9592 100644
--- a/target-arm/translate.c
+++ b/target-arm/translate.c
@@ -6968,7 +6968,7 @@ static int disas_neon_data_insn(CPUARMState * env, DisasContext *s, uint32_t ins
 
 static int disas_coproc_insn(CPUARMState * env, DisasContext *s, uint32_t insn)
 {
-    int cpnum, is64, crn, crm, opc1, opc2, isread, rt, rt2;
+    int cpnum, is64, crn, crm, opc1, opc2, isread, rt, rt2, ns;
     const ARMCPRegInfo *ri;
 
     cpnum = (insn >> 8) & 0xf;
@@ -7012,8 +7012,11 @@ static int disas_coproc_insn(CPUARMState * env, DisasContext *s, uint32_t insn)
     isread = (insn >> 20) & 1;
     rt = (insn >> 12) & 0xf;
 
+    /* Monitor mode is always treated as secure but cp register reads/writes
+     * can access secure and non-secure instances using SCR.NS bit*/
+    ns = IS_NS(s) ? 1 : !USE_SECURE_REG(env);
     ri = get_arm_cp_reginfo(s->cp_regs,
-                            ENCODE_CP_REG(cpnum, is64, crn, crm, opc1, opc2));
+            ENCODE_CP_REG(cpnum, is64, crn, crm, opc1, opc2, ns));
     if (ri) {
         /* Check access permissions */
         if (!cp_access_ok(s->current_pl, ri, isread)) {
@@ -7200,12 +7203,16 @@ static int disas_coproc_insn(CPUARMState * env, DisasContext *s, uint32_t insn)
      */
     if (is64) {
         qemu_log_mask(LOG_UNIMP, "%s access to unsupported AArch32 "
-                      "64 bit system register cp:%d opc1: %d crm:%d\n",
-                      isread ? "read" : "write", cpnum, opc1, crm);
+                      "64 bit system register cp:%d opc1: %d crm:%d "
+                      "(%s)\n",
+                      isread ? "read" : "write", cpnum, opc1, crm,
+                      ns ? "non-secure" : "secure");
     } else {
         qemu_log_mask(LOG_UNIMP, "%s access to unsupported AArch32 "
-                      "system register cp:%d opc1:%d crn:%d crm:%d opc2:%d\n",
-                      isread ? "read" : "write", cpnum, opc1, crn, crm, opc2);
+                      "system register cp:%d opc1:%d crn:%d crm:%d opc2:%d "
+                      "(%s)\n",
+                      isread ? "read" : "write", cpnum, opc1, crn, crm, opc2,
+                      ns ? "non-secure" : "secure");
     }
 
     return 1;
-- 
1.8.3.2