ipl3: add support for iQue hardware RNG

rasky · Dec 17, 2023 · 51e46ae · 51e46ae
1 parent 64a380d
commit 51e46ae
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Showing 2 changed files with 7 additions and 0 deletions.
diff --git a/boot/ipl3.c b/boot/ipl3.c
@@ -275,6 +275,12 @@ void stage1(void)
             // in-use by save state emulation, so we shouldn't access it anyway.
             if (memsize == 0x800000)
                 memsize = 0x7C0000;
+
+            // iQue has a hardware RNG. Use that to fetch 32 bits of entropy
+            uint32_t rng = 0;
+            for (int i=0;i<32;i++)
+                rng = (rng << 1) | (*MI_IQUE_RNG & 1);
+            entropy_add(rng);
         } else {
             // On warm boots, 
             int chip_id = 0;

diff --git a/boot/minidragon.h b/boot/minidragon.h
@@ -111,6 +111,7 @@ typedef uint64_t u_uint64_t __attribute__((aligned(1)));
 #define MI_WMODE_CLEAR_UPPER_MODE           0x1000
 #define MI_VERSION                          ((volatile uint32_t*)0xA4300004)
 #define MI_INTERRUPT                        ((volatile uint32_t*)0xA4300008)
+#define MI_IQUE_RNG                         ((volatile uint32_t*)0xA430002C)
 #define MI_WINTERRUPT_CLR_SP                0x0001
 #define MI_WINTERRUPT_SET_SP                0x0002
 #define MI_WINTERRUPT_CLR_SI                0x0004