From 21abfd4fd2380f5f156e34dcd169a5eba4876c2e Mon Sep 17 00:00:00 2001
From: Arthur Heymans <arthur.heymans@9elements.com>
Date: Fri, 25 Oct 2024 11:17:56 +0200
Subject: [PATCH] Add active flow in sw-emulator app

Signed-off-by: Arthur Heymans <arthur.heymans@9elements.com>
---
 rom/dev/Makefile            | 13 +++++++++
 sw-emulator/app/src/main.rs | 56 ++++++++++++++++++++++++++++++++-----
 2 files changed, 62 insertions(+), 7 deletions(-)

diff --git a/rom/dev/Makefile b/rom/dev/Makefile
index d0263c27a4..c4100d2022 100644
--- a/rom/dev/Makefile
+++ b/rom/dev/Makefile
@@ -125,6 +125,19 @@ run: build-emu build-fw-image build-rom
 		--recovery-image-fw $(TARGET_DIR)/caliptra-rom-test-fw \
 		--device-lifecycle unprovisioned \
 
+run-active: build-emu build-fw-image build-rom
+	cargo \
+		"--config=$(EXTRA_CARGO_CONFIG)" \
+		run \
+		-p caliptra-emu \
+		-- \
+		--req-idevid-csr \
+		--idevid-key-id-algo sha1 \
+		--rom $(TARGET_DIR)/caliptra-rom.bin \
+		--recovery-image-fw $(TARGET_DIR)/caliptra-rom-test-fw \
+		--device-lifecycle unprovisioned \
+		--active-mode \
+
 run-update: build-emu build-fw-image build-rom
 		cargo \
 		"--config=$(EXTRA_CARGO_CONFIG)" \
diff --git a/sw-emulator/app/src/main.rs b/sw-emulator/app/src/main.rs
index 2cae70601c..6e5a4f3939 100644
--- a/sw-emulator/app/src/main.rs
+++ b/sw-emulator/app/src/main.rs
@@ -39,6 +39,9 @@ use tock_registers::register_bitfields;
 /// Firmware Load Command Opcode
 const FW_LOAD_CMD_OPCODE: u32 = 0x4657_4C44;
 
+/// Recovery register interface download Command Opcode
+const RI_DOWNLOAD_FIRMWARE: u32 = 0x5249_4644;
+
 /// The number of CPU clock cycles it takes to write the firmware to the mailbox.
 const FW_WRITE_TICKS: u64 = 1000;
 
@@ -162,6 +165,11 @@ fn main() -> io::Result<()> {
                 .value_parser(value_parser!(u64))
                 .default_value(&(EXPECTED_CALIPTRA_BOOT_TIME_IN_CYCLES.to_string()))
         )
+        .arg(
+            arg!(--"active-mode" ... "Active mode: get image update via recovery register interface")
+                .required(false)
+                .action(ArgAction::SetTrue)
+        )
         .get_matches();
 
     let args_rom = args.get_one::<PathBuf>("rom").unwrap();
@@ -267,6 +275,11 @@ fn main() -> io::Result<()> {
         },
     );
 
+    let active_mode = args.get_flag("active-mode");
+
+    // Clippy seems wrong about this clone not being necessary
+    #[allow(clippy::redundant_clone)]
+    let firmware_buffer = current_fw_buf.clone();
     let bus_args = CaliptraRootBusArgs {
         rom: rom_buffer,
         log_dir: args_log_dir.clone(),
@@ -275,12 +288,20 @@ fn main() -> io::Result<()> {
             0xFF => exit(0x00),
             _ => print!("{}", val as char),
         }),
-        ready_for_fw_cb: ReadyForFwCb::new(move |args| {
-            let firmware_buffer = current_fw_buf.clone();
-            args.schedule_later(FW_WRITE_TICKS, move |mailbox: &mut MailboxInternal| {
-                upload_fw_to_mailbox(mailbox, firmware_buffer);
-            });
-        }),
+        ready_for_fw_cb: if active_mode {
+            ReadyForFwCb::new(move |args| {
+                args.schedule_later(FW_WRITE_TICKS, move |mailbox: &mut MailboxInternal| {
+                    rri_download(mailbox)
+                })
+            })
+        } else {
+            ReadyForFwCb::new(move |args| {
+                let firmware_buffer = firmware_buffer.clone();
+                args.schedule_later(FW_WRITE_TICKS, move |mailbox: &mut MailboxInternal| {
+                    upload_fw_to_mailbox(mailbox, firmware_buffer)
+                });
+            })
+        },
         security_state,
         upload_update_fw: UploadUpdateFwCb::new(move |mailbox: &mut MailboxInternal| {
             upload_fw_to_mailbox(mailbox, update_fw_buf.clone());
@@ -297,7 +318,12 @@ fn main() -> io::Result<()> {
         ..Default::default()
     };
 
-    let root_bus = CaliptraRootBus::new(&clock, bus_args);
+    let mut root_bus = CaliptraRootBus::new(&clock, bus_args);
+    // Populate the RRI data
+    if active_mode {
+        root_bus.recovery.cms_data = Some(current_fw_buf);
+    }
+
     let soc_ifc = unsafe {
         caliptra_registers::soc_ifc::RegisterBlock::new_with_mmio(
             0x3003_0000 as *mut u32,
@@ -457,6 +483,22 @@ fn upload_fw_to_mailbox(mailbox: &mut MailboxInternal, firmware_buffer: Rc<Vec<u
     soc_mbox.execute().write(|w| w.execute(true));
 }
 
+fn rri_download(mailbox: &mut MailboxInternal) {
+    let soc_mbox = mailbox.as_external().regs();
+    // Write the cmd to mailbox.
+
+    assert!(!soc_mbox.lock().read().lock());
+
+    // Set command
+    soc_mbox.cmd().write(|_| RI_DOWNLOAD_FIRMWARE);
+
+    // No data to send so set len to 0
+    soc_mbox.dlen().write(|_| 0);
+
+    // Execute
+    soc_mbox.execute().write(|w| w.execute(true));
+}
+
 fn download_idev_id_csr(
     mailbox: &mut MailboxInternal,
     path: Rc<PathBuf>,