robot tbeam cache error fix

Co-authored-by: Copilot <copilot@github.com>

src/platform/esp32/IramMemcpy.c

@@ -0,0 +1,42 @@
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdint.h>
+
+#include "esp_attr.h"
+
+#ifdef ESP32_FORCE_IRAM_MEMSET
+
+/*
+ * T-Beam/classic ESP32 boot workaround
+ * ------------------------------------
+ * During early flash operations the ESP32 disables cache, but some IRAM flash
+ * code paths still reach libc memcpy/memset. If those resolve to flash-resident
+ * implementations, startup can panic with cache-disabled access errors.
+ *
+ * We wrap memcpy/memset for the T-Beam environment. Fast path uses the
+ * normal libc routines when cache is enabled; slow path uses IRAM-safe byte
+ * loops when cache is disabled.
+ */
+
+extern void *__real_memcpy(void *dst, const void *src, size_t n);
+
+static inline bool IRAM_ATTR cache_is_enabled(void)
+{
+    return (*(volatile uint32_t *)0x3FF00040u) & (1u << 3);
+}
+
+extern void *IRAM_ATTR __wrap_memcpy(void *dst, const void *src, size_t n)
+{
+    if (cache_is_enabled()) {
+        return __real_memcpy(dst, src, n);
+    }
+
+    uint8_t *d = (uint8_t *)dst;
+    const uint8_t *s = (const uint8_t *)src;
+    while (n--) {
+        *d++ = *s++;
+    }
+    return dst;
+}
+
+#endif

src/platform/esp32/IramMemset.c

@@ -0,0 +1,42 @@
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdint.h>
+
+#include "esp_attr.h"
+
+#ifdef ESP32_FORCE_IRAM_MEMSET
+
+/*
+ * T-Beam/classic ESP32 boot workaround
+ * ------------------------------------
+ * During early flash operations the ESP32 disables cache, but some IRAM flash
+ * code paths still reach libc memcpy/memset. If those resolve to flash-resident
+ * implementations, startup can panic with cache-disabled access errors.
+ *
+ * We wrap memcpy/memset for the T-Beam environment. Fast path uses the
+ * normal libc routines when cache is enabled; slow path uses IRAM-safe byte
+ * loops when cache is disabled.
+ */
+
+extern void *__real_memset(void *dst, int c, size_t n);
+
+static inline bool IRAM_ATTR cache_is_enabled(void)
+{
+    return (*(volatile uint32_t *)0x3FF00040u) & (1u << 3);
+}
+
+extern void *IRAM_ATTR __wrap_memset(void *dst, int c, size_t n)
+{
+    if (cache_is_enabled()) {
+        return __real_memset(dst, c, n);
+    }
+
+    uint8_t *ptr = (uint8_t *)dst;
+    const uint8_t fill = (uint8_t)c;
+    while (n--) {
+        *ptr++ = fill;
+    }
+    return dst;
+}
+
+#endif