From 54ac2e007f4482907de01b5bfb5a17ded8722856 Mon Sep 17 00:00:00 2001
From: Dmitry Ilyin <widgetii@users.noreply.github.com>
Date: Mon, 6 Apr 2026 21:34:42 +0300
Subject: [PATCH] Add agent version and capabilities to INFO response

Extend RSP_INFO from 16 to 24 bytes with two new fields:
- agent_version (uint32_t): protocol version, currently 2
- capabilities (uint32_t): bitfield of supported features
  - flash_stream, sector_bitmap, page_skip, set_baud,
    reboot, selfupdate, scan

Host parses extended fields when present (len >= 24).
CLI displays version and capability list in `defib agent info`.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
---
 agent/main.c                | 21 +++++++++++++++++++--
 src/defib/agent/client.py   | 20 +++++++++++++++++++-
 src/defib/agent/protocol.py |  2 +-
 src/defib/cli/app.py        | 14 ++++++++++++++
 4 files changed, 53 insertions(+), 4 deletions(-)

diff --git a/agent/main.c b/agent/main.c
index 0a31205..9191b35 100644
--- a/agent/main.c
+++ b/agent/main.c
@@ -105,8 +105,23 @@ static int addr_readable(uint32_t addr, uint32_t size) {
     return 0;
 }
 
+/* Agent protocol version — increment on protocol changes */
+#define AGENT_VERSION       2
+
+/* Capability flags — advertise supported features */
+#define CAP_FLASH_STREAM    (1 << 0)  /* CMD_FLASH_STREAM with double-buffer */
+#define CAP_SECTOR_BITMAP   (1 << 1)  /* 0xFF sector skip in FLASH_STREAM */
+#define CAP_PAGE_SKIP       (1 << 2)  /* 0xFF page skip in programming */
+#define CAP_SET_BAUD        (1 << 3)  /* CMD_SET_BAUD for high-speed UART */
+#define CAP_REBOOT          (1 << 4)  /* CMD_REBOOT */
+#define CAP_SELFUPDATE      (1 << 5)  /* CMD_SELFUPDATE */
+#define CAP_SCAN            (1 << 6)  /* CMD_SCAN */
+
+#define AGENT_CAPS (CAP_FLASH_STREAM | CAP_SECTOR_BITMAP | CAP_PAGE_SKIP | \
+                    CAP_SET_BAUD | CAP_REBOOT | CAP_SELFUPDATE | CAP_SCAN)
+
 static void handle_info(void) {
-    uint8_t resp[16];
+    uint8_t resp[24];
     /* JEDEC ID in first 4 bytes (3 bytes + padding) */
     resp[0] = flash_info.jedec_id[0];
     resp[1] = flash_info.jedec_id[1];
@@ -115,7 +130,9 @@ static void handle_info(void) {
     write_le32(&resp[4], flash_info.size);
     write_le32(&resp[8], RAM_BASE);
     write_le32(&resp[12], 0x10000);    /* 64KB sector */
-    proto_send(RSP_INFO, resp, 16);
+    write_le32(&resp[16], AGENT_VERSION);
+    write_le32(&resp[20], AGENT_CAPS);
+    proto_send(RSP_INFO, resp, 24);
 }
 
 static void handle_read(const uint8_t *data, uint32_t len) {
diff --git a/src/defib/agent/client.py b/src/defib/agent/client.py
index 2eec246..1b2c4a6 100644
--- a/src/defib/agent/client.py
+++ b/src/defib/agent/client.py
@@ -192,6 +192,15 @@ async def _restore_baud(self) -> None:
             if ok:
                 self._current_baud = FALLBACK_BAUD
 
+    # Agent capability flags (must match agent/main.c)
+    CAP_FLASH_STREAM = 1 << 0
+    CAP_SECTOR_BITMAP = 1 << 1
+    CAP_PAGE_SKIP = 1 << 2
+    CAP_SET_BAUD = 1 << 3
+    CAP_REBOOT = 1 << 4
+    CAP_SELFUPDATE = 1 << 5
+    CAP_SCAN = 1 << 6
+
     async def get_info(self) -> dict[str, int | str]:
         """Request device info from the agent."""
         self._clear_rx_buffers()
@@ -209,13 +218,22 @@ async def get_info(self) -> dict[str, int | str]:
         self._ram_base = ram_base
         self._sector_size = sector_size
 
-        return {
+        result: dict[str, int | str] = {
             "jedec_id": f"{jedec[0]:02x}{jedec[1]:02x}{jedec[2]:02x}",
             "flash_size": flash_size,
             "ram_base": ram_base,
             "sector_size": sector_size,
         }
 
+        # Extended fields (agent version >= 2)
+        if len(data) >= 24:
+            version = struct.unpack("<I", data[16:20])[0]
+            caps = struct.unpack("<I", data[20:24])[0]
+            result["agent_version"] = version
+            result["capabilities"] = caps
+
+        return result
+
     async def read_memory(
         self,
         addr: int,
diff --git a/src/defib/agent/protocol.py b/src/defib/agent/protocol.py
index 8828be1..6a8b59e 100644
--- a/src/defib/agent/protocol.py
+++ b/src/defib/agent/protocol.py
@@ -18,7 +18,7 @@
   0x09  SCAN       — Scan flash health
 
 Responses (device → host):
-  0x81  INFO_RSP — chip_id(4B) + flash_size(4B) + ram_base(4B)
+  0x81  INFO_RSP — chip_id(4B) + flash_size(4B) + ram_base(4B) + sector_size(4B) + version(4B) + caps(4B)
   0x82  DATA     — seq(2B LE) + data(up to 1024B)
   0x83  ACK      — status(1B): 0=OK, 1=CRC error, 2=flash error
   0x84  CRC32_RSP— crc32(4B LE)
diff --git a/src/defib/cli/app.py b/src/defib/cli/app.py
index 1bccb2e..11952e8 100644
--- a/src/defib/cli/app.py
+++ b/src/defib/cli/app.py
@@ -930,6 +930,20 @@ async def _agent_info_async(port: str, output: str) -> None:
         console.print(f"  Flash size:  {int(info.get('flash_size', 0)) // 1024} KB")
         console.print(f"  RAM base:    0x{int(info.get('ram_base', 0)):08x}")
         console.print(f"  Sector size: {int(info.get('sector_size', 0)) // 1024} KB")
+        if "agent_version" in info:
+            caps = int(info.get("capabilities", 0))
+            cap_names = []
+            cap_map = [
+                (1 << 0, "flash_stream"), (1 << 1, "sector_bitmap"),
+                (1 << 2, "page_skip"), (1 << 3, "set_baud"),
+                (1 << 4, "reboot"), (1 << 5, "selfupdate"),
+                (1 << 6, "scan"),
+            ]
+            for bit, name in cap_map:
+                if caps & bit:
+                    cap_names.append(name)
+            console.print(f"  Agent ver:   {info['agent_version']}")
+            console.print(f"  Capabilities: {', '.join(cap_names) or 'none'}")
 
 
 @agent_app.command("read")