Fixes for PUF ROT

wolfSSL · Feb 3, 2025 · 39af424 · 39af424
1 parent 7cf327f
commit 39af424
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Showing 2 changed files with 29 additions and 18 deletions.
diff --git a/hal/zynq.c b/hal/zynq.c
@@ -288,7 +288,11 @@ void wc_Sha3_384_Free(wc_Sha3* sha)
 #endif
 
 /* CSU PUF */
-#define PUF_REG_TIMEOUT 500000
+#ifdef CSU_PUF_ROT
+#define CSU_PUF_SYNDROME_WORDS 386
+#ifndef CSU_PUF_REG_TIMEOUT
+#define CSU_PUF_REG_TIMEOUT    500000
+#endif
 int csu_puf_register(uint32_t* syndrome, uint32_t* syndromeSz, uint32_t* chash,
     uint32_t* aux)
 {
@@ -299,16 +303,19 @@ int csu_puf_register(uint32_t* syndrome, uint32_t* syndromeSz, uint32_t* chash,
     wolfBoot_printf("CSU Puf Register\n");
 #endif
 
-    pmu_mmio_write(CSU_PUF_CFG0, CSU_PUF_CFG0_INIT);
-    pmu_mmio_write(CSU_PUF_CFG1, CSU_PUF_CFG1_INIT);
-    pmu_mmio_write(CSU_PUF_SHUTTER, CSU_PUF_SHUTTER_INIT);
-    pmu_mmio_write(CSU_PUF_CMD, CSU_PUF_CMD_REGISTRATION);
-    while (1) {
+    ret = pmu_mmio_write(CSU_PUF_CFG0, CSU_PUF_CFG0_INIT);
+    if (ret == 0)
+        ret = pmu_mmio_write(CSU_PUF_CFG1, CSU_PUF_CFG1_INIT);
+    if (ret == 0)
+        ret = pmu_mmio_write(CSU_PUF_SHUTTER, CSU_PUF_SHUTTER_INIT);
+    if (ret == 0)
+        ret = pmu_mmio_write(CSU_PUF_CMD, CSU_PUF_CMD_REGISTRATION);
+    while (ret == 0) {
         /* Wait for PUF status done */
         while (((puf_status = pmu_mmio_read(CSU_PUF_STATUS))
                 & CSU_PUF_STATUS_SYN_WRD_RDY_MASK) == 0
-            && ++timeout < PUF_REG_TIMEOUT);
-        if (timeout == PUF_REG_TIMEOUT) {
+            && ++timeout < CSU_PUF_REG_TIMEOUT);
+        if (timeout == CSU_PUF_REG_TIMEOUT) {
             ret = -1; /* timeout */
             break;
         }
@@ -341,14 +348,16 @@ int csu_puf_register(uint32_t* syndrome, uint32_t* syndromeSz, uint32_t* chash,
 
     return ret;
 }
+#endif /* CSU_PUF_ROT */
 
-#define CSU_PUF_SYNDROME_WORDS 386
 int csu_init(void)
 {
-    int ret;
+    int ret = 0;
+#ifdef CSU_PUF_ROT
     uint32_t syndrome[CSU_PUF_SYNDROME_WORDS];
     uint32_t syndromeSz = (uint32_t)sizeof(syndrome);
     uint32_t chash=0, aux=0;
+#endif
     uint32_t reg1  = pmu_mmio_read(CSU_IDCODE);
     uint32_t reg2 = pmu_mmio_read(CSU_VERSION);
 
@@ -371,7 +380,9 @@ int csu_init(void)
     hal_delay_ms(500); /* give time for debugger to break */
 #endif
 
+#ifdef CSU_PUF_ROT
     ret = csu_puf_register(syndrome, &syndromeSz, &chash, &aux);
+#endif
 
     return ret;
 }

diff --git a/hal/zynq.h b/hal/zynq.h
@@ -485,14 +485,14 @@
 #define CSU_PUF_CMD_REGISTRATION 0x1 /* Key registration */
 
 #define CSU_PUF_CFG0_INIT        0x2
-#define CSU_PUF_CFG1_INIT        0x0C230090 /* 0x00080080 */
-#define CSU_PUF_SHUTTER_INIT     0x0100005E /* 0x01000100 */
-
-#define CSU_PUF_STATUS_OVERFLOW_MASK    0x30000000 /* Overflow, if bits are not 0. Reduce SHUT[SOPEN] value. */
-#define CSU_PUF_STATUS_AUX_MASK         0x0FFFFFF0 /* During provisioning, auxiliary sundrome bits are stored here and must be written to the eFuse or boot image. */
-#define CSU_PUF_STATUS_KEY_RDY_MASK     0x00000008
-#define CSU_PUF_STATUS_KEY_ZERO_MASK    0x00000002 /* Indicates that the PUF key has been zeroized */
-#define CSU_PUF_STATUS_SYN_WRD_RDY_MASK 0x00000001 /* Indicates a syndrome word is ready in the PUF_WORD register. */
+#define CSU_PUF_CFG1_INIT        0x0C230090U /* 4K */
+#define CSU_PUF_SHUTTER_INIT     0x00100005E /* 0x01000100 */
+
+#define CSU_PUF_STATUS_OVERFLOW_MASK    (0x3U << 28)     /* Overflow, if bits are not 0. Reduce SHUT[SOPEN] value. */
+#define CSU_PUF_STATUS_AUX_MASK         (0xFFFFFFU << 4) /* During provisioning, auxiliary sundrome bits are stored here and must be written to the eFuse or boot image. */
+#define CSU_PUF_STATUS_KEY_RDY_MASK     (0x1U << 3)      /* Indicates that the key is ready */
+#define CSU_PUF_STATUS_KEY_ZERO_MASK    (0x1U << 1)      /* Indicates that the PUF key has been zeroized */
+#define CSU_PUF_STATUS_SYN_WRD_RDY_MASK (0x1U << 0)      /* Indicates a syndrome word is ready in the PUF_WORD register */
 
 /* SHA3 */
 #define CSU_SHA_START  (CSU_BASE + 0x2000U)