feat(ble): added xor checksum for integrity check performance optimization

(cherry picked from commit c604afa272f9b4e81835562eb812d86288f040c5)

Co-authored-by: Zhou Xiao <zhouxiao@espressif.com>

components/bt/common/ble_log/Kconfig.in

@@ -91,6 +91,12 @@ if BLE_LOG_ENABLED
             checksum of frame head and payload all together by default, or only
             calculate the checksum of frame head to minimize performance decrease
 
+    config BLE_LOG_XOR_CHECKSUM_ENABLED
+        bool "Enable XOR checksum for BLE Log payload integrity check"
+        default y
+        help
+            XOR checksum is introduced for integrity check performance optimization.
+
     config BLE_LOG_ENH_STAT_ENABLED
         bool "Enable enhanced statistics for BLE Log"
         default n

components/bt/common/ble_log/src/ble_log_util.c

@@ -17,7 +17,60 @@ portMUX_TYPE ble_log_spin_lock = portMUX_INITIALIZER_UNLOCKED;
 #endif /* !UNIT_TEST */
 
 /* INTERNAL INTERFACE */
-BLE_LOG_IRAM_ATTR uint32_t ble_log_fast_checksum(const uint8_t *data, size_t len)
+#if CONFIG_BLE_LOG_XOR_CHECKSUM_ENABLED
+#include "esp_compiler.h"
+
+static inline uint32_t ror32(uint32_t word, uint32_t shift)
+{
+    if (unlikely(shift == 0)) {
+        return word;
+    }
+    return (word >> shift) | (word << ((32 - shift) & 0x1F));
+}
+
+__attribute__((optimize("-O3")))
+BLE_LOG_IRAM_ATTR
+uint32_t ble_log_fast_checksum(const uint8_t *data, size_t len)
+{
+    /* Validate input length */
+    if (unlikely(len == 0)) {
+        return 0;
+    }
+
+    /* Step 1: Force 32-bit align read and calculate offset */
+    const uint32_t start_offset_shift = ((uintptr_t)data & 0x3) << 3;
+    const uint32_t *p_aligned = (const uint32_t *)((uintptr_t)data & ~0x3);
+    const uint32_t *p_end_aligned = (const uint32_t *)((uintptr_t)(data + len) & ~0x3);
+
+    /* Step 2: Handle first word with mask (Little endian) */
+    uint32_t checksum = (*p_aligned) & (0xFFFFFFFFU << start_offset_shift);
+
+    /* Step 3: Check if first word is last word */
+    const uint32_t end_offset_shift = ((uintptr_t)(data + len) & 0x3) << 3;
+    const uint32_t end_offset_shift_mask = ~(0xFFFFFFFFU << end_offset_shift);
+    if (unlikely(p_aligned == p_end_aligned)) {
+        if (end_offset_shift) {
+            checksum &= end_offset_shift_mask;
+        }
+    } else {
+        /* Step 4: Handle word in the middle */
+        p_aligned++;
+        while (p_aligned < p_end_aligned) {
+            checksum ^= *p_aligned++;
+        }
+
+        /* Step 5: Handle last word with mask (Little endian) */
+        if (end_offset_shift) {
+            checksum ^= (*p_aligned) & end_offset_shift_mask;
+        }
+    }
+
+    /* Step 6: Rotate the final result */
+    return ror32(checksum, start_offset_shift);
+}
+#else /* !CONFIG_BLE_LOG_XOR_CHECKSUM_ENABLED */
+BLE_LOG_IRAM_ATTR
+uint32_t ble_log_fast_checksum(const uint8_t *data, size_t len)
 {
     uint32_t sum = 0;
     size_t i = 0;
@@ -46,3 +99,4 @@ BLE_LOG_IRAM_ATTR uint32_t ble_log_fast_checksum(const uint8_t *data, size_t len
 
     return sum;
 }
+#endif /* CONFIG_BLE_LOG_XOR_CHECKSUM_ENABLED */

components/bt/common/ble_log/src/internal_include/ble_log_util.h

@@ -130,7 +130,7 @@ bool ble_log_cas_acquire(volatile bool *cas_lock);
 void ble_log_cas_release(volatile bool *cas_lock);
 #endif /* UNIT_TEST */
 
-#define BLE_LOG_VERSION                         (2)
+#define BLE_LOG_VERSION                         (3)
 
 /* TYPEDEF */
 typedef enum {