From 1f628e359c08666407fd2e30e4aa193a51ddbc48 Mon Sep 17 00:00:00 2001
From: Jesse Braham <jessebraham@users.noreply.github.com>
Date: Fri, 22 Dec 2023 14:28:21 +0000
Subject: [PATCH] Add support for the ESP32-P4 (#61)

* Add support for the ESP32-P4

* Update the CI workflow to check the ESP32-P4
---
 .github/workflows/ci.yml |  1 +
 Cargo.toml               |  3 ++-
 build.rs                 |  2 ++
 src/lib.rs               | 23 +++++++++++++++++++++++
 4 files changed, 28 insertions(+), 1 deletion(-)

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 45c0bfd..4d66b4c 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -28,6 +28,7 @@ jobs:
             { chip: "esp32c3", target: "riscv32imc-unknown-none-elf" },
             { chip: "esp32c6", target: "riscv32imac-unknown-none-elf" },
             { chip: "esp32h2", target: "riscv32imac-unknown-none-elf" },
+            { chip: "esp32p4", target: "riscv32imafc-unknown-none-elf" },
           ]
 
     steps:
diff --git a/Cargo.toml b/Cargo.toml
index 27ad790..1d68317 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -31,6 +31,7 @@ esp32c2 = []
 esp32c3 = []
 esp32c6 = []
 esp32h2 = []
+esp32p4 = []
 esp32s2 = []
 esp32s3 = []
 esp8266 = []
@@ -38,7 +39,7 @@ esp8266 = []
 # You must enable exactly 1 of the below features to enable to intended
 # communication method (note that "uart" is enabled by default):
 uart        = []
-jtag-serial = ["portable-atomic"] # C3, C6, H2, and S3 only!
+jtag-serial = ["portable-atomic"] # C3, C6, H2, P4, and S3 only!
 no-op       = []
 
 # Enables a `defmt` backend usable with espflash. We force rzcobs encoding to simplify implementation
diff --git a/build.rs b/build.rs
index e970462..0f9e3bc 100644
--- a/build.rs
+++ b/build.rs
@@ -6,6 +6,7 @@ fn main() {
         cfg!(feature = "esp32c3"),
         cfg!(feature = "esp32c6"),
         cfg!(feature = "esp32h2"),
+        cfg!(feature = "esp32p4"),
         cfg!(feature = "esp32s2"),
         cfg!(feature = "esp32s3"),
         cfg!(feature = "esp8266"),
@@ -33,6 +34,7 @@ fn main() {
         && !(cfg!(feature = "esp32c3")
             || cfg!(feature = "esp32c6")
             || cfg!(feature = "esp32h2")
+            || cfg!(feature = "esp32p4")
             || cfg!(feature = "esp32s3"))
     {
         panic!(
diff --git a/src/lib.rs b/src/lib.rs
index 7eb2ff4..244022d 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -90,6 +90,7 @@ impl Printer {
         feature = "esp32c3",
         feature = "esp32c6",
         feature = "esp32h2",
+        feature = "esp32p4",
         feature = "esp32s3"
     )
 ))]
@@ -106,6 +107,11 @@ mod serial_jtag_printer {
     #[cfg(any(feature = "esp32c6", feature = "esp32h2"))]
     const SERIAL_JTAG_CONF_REG: usize = 0x6000_F004;
 
+    #[cfg(feature = "esp32p4")]
+    const SERIAL_JTAG_FIFO_REG: usize = 0x500D_2000;
+    #[cfg(feature = "esp32p4")]
+    const SERIAL_JTAG_CONF_REG: usize = 0x500D_2004;
+
     #[cfg(feature = "esp32s3")]
     const SERIAL_JTAG_FIFO_REG: usize = 0x6003_8000;
     #[cfg(feature = "esp32s3")]
@@ -329,6 +335,23 @@ mod uart_printer {
         }
     }
 
+    #[cfg(feature = "esp32p4")]
+    impl Functions for Device {
+        const TX_ONE_CHAR: usize = 0x4FC0_0054;
+
+        fn flush() {
+            unsafe {
+                const TX_FLUSH: usize = 0x4FC0_0074;
+                const GET_CHANNEL: usize = 0x4FC0_0038;
+
+                let tx_flush: unsafe extern "C" fn(u8) = core::mem::transmute(TX_FLUSH);
+                let get_channel: unsafe extern "C" fn() -> u8 = core::mem::transmute(GET_CHANNEL);
+
+                tx_flush(get_channel());
+            }
+        }
+    }
+
     impl super::Printer {
         pub fn write_bytes_assume_cs(&mut self, bytes: &[u8]) {
             for chunk in bytes.chunks(Device::CHUNK_SIZE) {