From 5cf2d9042881bb3e352391f2865ae461a415798f Mon Sep 17 00:00:00 2001
From: Denis Drakhnya <numas13@gmail.com>
Date: Tue, 24 Nov 2020 00:02:11 +0200
Subject: [PATCH] target: e2k: Add %idr.

---
 target/e2k/cpu.c    |  1 +
 target/e2k/cpu.h    | 22 ++++++++++++++++++++++
 target/e2k/helper.c |  2 ++
 3 files changed, 25 insertions(+)

diff --git a/target/e2k/cpu.c b/target/e2k/cpu.c
index 7ef83c434f..e4b61e7db0 100644
--- a/target/e2k/cpu.c
+++ b/target/e2k/cpu.c
@@ -56,6 +56,7 @@ static void e2k_cpu_reset(DeviceState *dev)
     env->boff = 8;
     env->bsize = 8;
     env->bcur = 0;
+    env->idr = 0x3a207; // mimic 8c
 }
 
 #ifdef CONFIG_SOFTMMU
diff --git a/target/e2k/cpu.h b/target/e2k/cpu.h
index e3b515181b..a840c0d543 100644
--- a/target/e2k/cpu.h
+++ b/target/e2k/cpu.h
@@ -211,6 +211,27 @@ void e2k_tcg_initialize(void);
 #define UPSR_IUC_OFF 10 /* ignore access right for uncached pages */
 #define UPSR_IUC_BIT (1 << UPSR_IUC_OFF)
 
+#define IDR_MDL_OFF 0 /* CPU model number */
+#define IDR_MDL_END 7
+#define IDR_MDL_LEN (IDR_MDL_END - IDR_MDL_OFF + 1)
+#define IDR_REV_OFF 8 /* revision number */
+#define IDR_REV_END 11
+#define IDR_REV_LEN (IDR_REV_END - IDR_REV_OFF + 1)
+#define IDR_WBL_OFF 12 /* write-back length of L2 */
+#define IDR_WBL_END 14
+#define IDR_WBL_LEN (IDR_WBL_END - IDR_WBL_OFF + 1)
+#define IDR_MS_OFF 15 /* model specific info */
+#define IDR_MS_END 63
+#define IDR_MS_LEN (IDR_MS_END - IDR_MS_OFF + 1)
+
+/* Cache write-back length */
+#define IDR_WBL_0   0x0 /* none CPU internal cache */
+#define IDR_WBL_32  0x1
+#define IDR_WBL_64  0x2
+#define IDR_WBL_128 0x3
+#define IDR_WBL_256 0x4
+#define IDR_WBL_TO_BYTES(wbl) ((wbl) ? (1 << ((wbs) + 4)) : 1)
+
 typedef enum {
     E2K_EXCP_UNIMPL = 0x01,
     E2K_EXCP_SYSCALL = 0x02,
@@ -278,6 +299,7 @@ typedef struct CPUArchState {
     target_ulong nip; /* next instruction address */
     
     uint32_t upsr;
+    uint64_t idr;
 
     uint32_t pfpfr; // Packed Floating Point Flag Register (PFPFR)
     uint32_t fpcr; // Floating point control register (FPCR)
diff --git a/target/e2k/helper.c b/target/e2k/helper.c
index d415840775..4c667f0f5d 100644
--- a/target/e2k/helper.c
+++ b/target/e2k/helper.c
@@ -291,6 +291,8 @@ uint64_t helper_state_reg_get(CPUE2KState *env, int reg)
         return env->ip;
     case 0x83: /* %lsr */
         return env->lsr;
+    case 0x8a: /* %idr */
+        return env->idr;
     default:
         /* TODO: exception */
         qemu_log_mask(LOG_UNIMP, "unknown register 0x%x\n", reg);