[ot] hw/opentitan: ot_otp: remove useless entropy API

rivos-eblot · rivos-eblot · commit 6c121229ceae · 2025-10-29T14:29:46.000+01:00
Move the en_csrng_sw_app_read field to where it belongs: OtOTPHWCfg

Signed-off-by: Emmanuel Blot &lt;eblot@rivosinc.com&gt;
diff --git a/hw/opentitan/ot_csrng.c b/hw/opentitan/ot_csrng.c
@@ -1822,24 +1822,18 @@ static void ot_csrng_regs_write(void *opaque, hwaddr addr, uint64_t val64,
         if (change) {
             xtrace_ot_csrng_info("handling CTRL change", val32);
             ot_csrng_handle_enable(s);
-            bool granted;
             OtOTPClass *oc =
                 OBJECT_GET_CLASS(OtOTPClass, s->otp_ctrl, TYPE_OT_OTP);
-            const OtOTPEntropyCfg *entropy_cfg =
-                oc->get_entropy_cfg(s->otp_ctrl);
-            if (entropy_cfg) {
-                granted =
-                    entropy_cfg->en_csrng_sw_app_read == OT_MULTIBITBOOL8_TRUE;
-            } else {
-                /* defaults to granted if no entropy config in OTP */
-                granted = true;
-            }
-            if (granted) {
+            const OtOTPHWCfg *hw_cfg = oc->get_hw_cfg(s->otp_ctrl);
+            g_assert(hw_cfg);
+            if (hw_cfg->en_csrng_sw_app_read == OT_MULTIBITBOOL8_TRUE) {
                 uint32_t sw_app_en = FIELD_EX32(val32, CTRL, SW_APP_ENABLE);
                 s->sw_app_granted = sw_app_en == OT_MULTIBITBOOL4_TRUE;
                 uint32_t read_int = FIELD_EX32(val32, CTRL, READ_INT_STATE);
                 s->read_int_granted = read_int == OT_MULTIBITBOOL4_TRUE;
             } else {
+                qemu_log_mask(LOG_GUEST_ERROR, "%s: SW APP disabled in OTP\n",
+                              __func__);
                 s->sw_app_granted = false;
                 s->read_int_granted = false;
             }
diff --git a/hw/opentitan/ot_entropy_src.c b/hw/opentitan/ot_entropy_src.c
@@ -1871,10 +1871,6 @@ static void ot_entropy_src_reset_enter(Object *obj, ResetType type)
         ibex_irq_set(&s->alerts[ix], 0);
     }
 
-    OtOTPClass *oc = OBJECT_GET_CLASS(OtOTPClass, s->otp_ctrl, TYPE_OT_OTP);
-    const OtOTPEntropyCfg *entropy_cfg = oc->get_entropy_cfg(s->otp_ctrl);
-    g_assert(entropy_cfg);
-
     ot_entropy_src_change_state(s, ENTROPY_SRC_IDLE);
 }
 
diff --git a/hw/opentitan/ot_otp_dj.c b/hw/opentitan/ot_otp_dj.c
@@ -2926,14 +2926,7 @@ static const OtOTPHWCfg *ot_otp_dj_get_hw_cfg(const OtOTPState *s)
 {
     const OtOTPDjState *ds = OT_OTP_DJ(s);
 
-    return ds->hw_cfg;
-}
-
-static const OtOTPEntropyCfg *ot_otp_dj_get_entropy_cfg(const OtOTPState *s)
-{
-    (void)s;
-    /* not present Darjeeling OTP */
-    return NULL;
+    return (const OtOTPHWCfg *)ds->hw_cfg;
 }
 
 static void ot_otp_dj_request_entropy_bh(void *opaque)
@@ -3550,6 +3543,10 @@ static void ot_otp_dj_pwr_load_hw_cfg(OtOTPDjState *s)
     hw_cfg->en_sram_ifetch =
         s->blk ? (uint8_t)otp->data[R_HW_CFG1_EN_SRAM_IFETCH] :
                  OT_MULTIBITBOOL8_TRUE;
+    /* do not prevent CSRNG app reads if no OTP configuration is loaded */
+    hw_cfg->en_csrng_sw_app_read =
+        s->blk ? (uint8_t)otp->data[R_HW_CFG1_EN_CSRNG_SW_APP_READ] :
+                 OT_MULTIBITBOOL8_TRUE;
 }
 
 static void ot_otp_dj_pwr_load_tokens(OtOTPDjState *s)
@@ -3960,7 +3957,7 @@ static void ot_otp_dj_reset_enter(Object *obj, ResetType type)
      *
      * File back-end storage (loading) is processed from
      * the ot_otp_dj_pwr_otp_bh handler, to ensure data is reloaded from the
-     * backend on each reset, prior to this very reset fuction. This reset
+     * backend on each reset, prior to this very reset function. This reset
      * function should not alter the storage content.
      *
      * Ideally the OTP reset functions should be decoupled from the regular
@@ -3988,6 +3985,7 @@ static void ot_otp_dj_reset_enter(Object *obj, ResetType type)
     s->keygen->edn_sched = false;
 
     memset(s->regs, 0, REGS_COUNT * sizeof(uint32_t));
+    memset(s->hw_cfg, 0, sizeof(*s->hw_cfg));
 
     s->regs[R_DIRECT_ACCESS_REGWEN] = 0x00000001u;
     s->regs[R_CHECK_TRIGGER_REGWEN] = 0x00000001u;
@@ -4070,7 +4068,7 @@ static void ot_otp_dj_realize(DeviceState *dev, Error **errp)
 
     /*
      * Set the OTP drive's permissions now during realization. We can't leave it
-     * until reset because QEMU might have `-deamonize`d and changed directory,
+     * until reset because QEMU might have `-daemonize`d and changed directory,
      * invalidating the filesystem path to the OTP image.
      */
     if (s->blk) {
@@ -4187,7 +4185,6 @@ static void ot_otp_dj_class_init(ObjectClass *klass, void *data)
 
     oc->get_lc_info = &ot_otp_dj_get_lc_info;
     oc->get_hw_cfg = &ot_otp_dj_get_hw_cfg;
-    oc->get_entropy_cfg = &ot_otp_dj_get_entropy_cfg;
     oc->get_otp_key = &ot_otp_dj_get_otp_key;
     oc->get_keymgr_secret = &ot_otp_dj_get_keymgr_secret;
     oc->program_req = &ot_otp_dj_program_req;
diff --git a/hw/opentitan/ot_otp_eg.c b/hw/opentitan/ot_otp_eg.c
@@ -699,7 +699,6 @@ struct OtOTPEgState {
 
     OtOTPStorage *otp;
     OtOTPHWCfg *hw_cfg;
-    OtOTPEntropyCfg *entropy_cfg;
     OtOTPTokens *tokens;
     char *hexstr;
 
@@ -2803,14 +2802,7 @@ static const OtOTPHWCfg *ot_otp_eg_get_hw_cfg(const OtOTPState *s)
 {
     const OtOTPEgState *es = OT_OTP_EG(s);
 
-    return es->hw_cfg;
-}
-
-static const OtOTPEntropyCfg *ot_otp_eg_get_entropy_cfg(const OtOTPState *s)
-{
-    const OtOTPEgState *es = OT_OTP_EG(s);
-
-    return es->entropy_cfg;
+    return (const OtOTPHWCfg *)es->hw_cfg;
 }
 
 static void ot_otp_eg_request_entropy_bh(void *opaque)
@@ -3425,7 +3417,6 @@ static void ot_otp_eg_pwr_load_hw_cfg(OtOTPEgState *s)
 {
     OtOTPStorage *otp = s->otp;
     OtOTPHWCfg *hw_cfg = s->hw_cfg;
-    OtOTPEntropyCfg *entropy_cfg = s->entropy_cfg;
 
     memcpy(hw_cfg->device_id, &otp->data[R_HW_CFG0_DEVICE_ID],
            sizeof(hw_cfg->device_id));
@@ -3436,7 +3427,7 @@ static void ot_otp_eg_pwr_load_hw_cfg(OtOTPEgState *s)
         s->blk ? (uint8_t)otp->data[R_HW_CFG1_EN_SRAM_IFETCH] :
                  OT_MULTIBITBOOL8_TRUE;
     /* do not prevent CSRNG app reads if no OTP configuration is loaded */
-    entropy_cfg->en_csrng_sw_app_read =
+    hw_cfg->en_csrng_sw_app_read =
         s->blk ? (uint8_t)otp->data[R_HW_CFG1_EN_CSRNG_SW_APP_READ] :
                  OT_MULTIBITBOOL8_TRUE;
 }
@@ -3944,7 +3935,7 @@ static void ot_otp_eg_reset_enter(Object *obj, ResetType type)
      *
      * File back-end storage (loading) is processed from
      * the ot_otp_eg_pwr_otp_bh handler, to ensure data is reloaded from the
-     * backend on each reset, prior to this very reset fuction. This reset
+     * backend on each reset, prior to this very reset function. This reset
      * function should not alter the storage content.
      *
      * Ideally the OTP reset functions should be decoupled from the regular
@@ -3972,6 +3963,7 @@ static void ot_otp_eg_reset_enter(Object *obj, ResetType type)
     s->keygen->edn_sched = false;
 
     memset(s->regs, 0, REGS_COUNT * sizeof(uint32_t));
+    memset(s->hw_cfg, 0, sizeof(*s->hw_cfg));
 
     s->regs[R_DIRECT_ACCESS_REGWEN] = 0x1u;
     s->regs[R_CHECK_TRIGGER_REGWEN] = 0x1u;
@@ -4044,7 +4036,7 @@ static void ot_otp_eg_realize(DeviceState *dev, Error **errp)
 
     /*
      * Set the OTP drive's permissions now during realization. We can't leave it
-     * until reset because QEMU might have `-deamonize`d and changed directory,
+     * until reset because QEMU might have `-daemonize`d and changed directory,
      * invalidating the filesystem path to the OTP image.
      */
     if (s->blk) {
@@ -4104,7 +4096,6 @@ static void ot_otp_eg_init(Object *obj)
                             OT_LC_BROADCAST, OT_OTP_LC_BROADCAST_COUNT);
 
     s->hw_cfg = g_new0(OtOTPHWCfg, 1u);
-    s->entropy_cfg = g_new0(OtOTPEntropyCfg, 1u);
     s->tokens = g_new0(OtOTPTokens, 1u);
     s->regs = g_new0(uint32_t, REGS_COUNT);
     s->dai = g_new0(OtOTPDAIController, 1u);
@@ -4163,7 +4154,6 @@ static void ot_otp_eg_class_init(ObjectClass *klass, void *data)
 
     oc->get_lc_info = &ot_otp_eg_get_lc_info;
     oc->get_hw_cfg = &ot_otp_eg_get_hw_cfg;
-    oc->get_entropy_cfg = &ot_otp_eg_get_entropy_cfg;
     oc->get_otp_key = &ot_otp_eg_get_otp_key;
     oc->get_keymgr_secret = &ot_otp_eg_get_keymgr_secret;
     oc->program_req = &ot_otp_eg_program_req;
diff --git a/include/hw/opentitan/ot_otp.h b/include/hw/opentitan/ot_otp.h
@@ -57,7 +57,7 @@ typedef enum {
 #define OT_OTP_HWCFG_SOC_DBG_STATE_BYTES 4u
 
 /*
- * Hardware configuration (for HW_CFG partition)
+ * Hardware configuration (for HW_CFG partitions)
  */
 typedef struct {
     uint8_t device_id[OT_OTP_HWCFG_DEVICE_ID_BYTES];
@@ -66,12 +66,8 @@ typedef struct {
     uint8_t soc_dbg_state[OT_OTP_HWCFG_SOC_DBG_STATE_BYTES];
     /* the following value is stored as OT_MULTIBITBOOL8 */
     uint8_t en_sram_ifetch;
-} OtOTPHWCfg;
-
-typedef struct {
-    /* the following values are stored as OT_MULTIBITBOOL8 */
     uint8_t en_csrng_sw_app_read;
-} OtOTPEntropyCfg;
+} OtOTPHWCfg;
 
 typedef enum {
     OTP_TOKEN_TEST_UNLOCK,
@@ -158,14 +154,6 @@ struct OtOTPClass {
      */
     const OtOTPHWCfg *(*get_hw_cfg)(const OtOTPState *s);
 
-    /*
-     * Retrieve entropy configuration.
-     *
-     * @s the OTP device
-     * @return the entropy config data (may be NULL if not present in OTP)
-     */
-    const OtOTPEntropyCfg *(*get_entropy_cfg)(const OtOTPState *s);
-
     /*
      * Retrieve SRAM scrambling key.
      *

Original file line number	Diff line number	Diff line change
`@@ -1871,10 +1871,6 @@ static void ot_entropy_src_reset_enter(Object *obj, ResetType type)`
`1871`	`1871`	`ibex_irq_set(&s->alerts[ix], 0);`
`1872`	`1872`	`}`
`1873`	`1873`
`1874`		`- OtOTPClass *oc = OBJECT_GET_CLASS(OtOTPClass, s->otp_ctrl, TYPE_OT_OTP);`
`1875`		`- const OtOTPEntropyCfg *entropy_cfg = oc->get_entropy_cfg(s->otp_ctrl);`
`1876`		`- g_assert(entropy_cfg);`
`1877`		`-`
`1878`	`1874`	`ot_entropy_src_change_state(s, ENTROPY_SRC_IDLE);`
`1879`	`1875`	`}`
`1880`	`1876`