From 855b26aa1993f942886cc9b06ad0d77879cb5fd3 Mon Sep 17 00:00:00 2001
From: pca006132 <john.lck40@gmail.com>
Date: Mon, 13 Jul 2020 14:59:56 +0800
Subject: [PATCH] Logger: ported log_buffer.

---
 src/runtime/src/logger.rs | 111 ++++++++++++++++++++++++++++++++++++++
 src/runtime/src/main.rs   |  13 ++++-
 2 files changed, 122 insertions(+), 2 deletions(-)
 create mode 100644 src/runtime/src/logger.rs

diff --git a/src/runtime/src/logger.rs b/src/runtime/src/logger.rs
new file mode 100644
index 00000000..2e3caca4
--- /dev/null
+++ b/src/runtime/src/logger.rs
@@ -0,0 +1,111 @@
+use core::cell::{Cell, RefCell, RefMut};
+use core::fmt::Write;
+use log::{Log, LevelFilter};
+use log_buffer::LogBuffer;
+use libboard_zynq::{println, timer::GlobalTimer};
+
+pub struct LogBufferRef<'a> {
+    buffer:        RefMut<'a, LogBuffer<&'static mut [u8]>>,
+    old_log_level: LevelFilter
+}
+
+impl<'a> LogBufferRef<'a> {
+    fn new(buffer: RefMut<'a, LogBuffer<&'static mut [u8]>>) -> LogBufferRef<'a> {
+        let old_log_level = log::max_level();
+        log::set_max_level(LevelFilter::Off);
+        LogBufferRef { buffer, old_log_level }
+    }
+
+    pub fn is_empty(&self) -> bool {
+        self.buffer.is_empty()
+    }
+
+    pub fn clear(&mut self) {
+        self.buffer.clear()
+    }
+
+    pub fn extract(&mut self) -> &str {
+        self.buffer.extract()
+    }
+}
+
+impl<'a> Drop for LogBufferRef<'a> {
+    fn drop(&mut self) {
+        log::set_max_level(self.old_log_level)
+    }
+}
+
+pub struct BufferLogger {
+    buffer:      RefCell<LogBuffer<&'static mut [u8]>>,
+    uart_filter: Cell<LevelFilter>
+}
+
+static mut LOGGER: Option<BufferLogger> = None;
+
+impl BufferLogger {
+    pub fn new(buffer: &'static mut [u8]) -> BufferLogger {
+        BufferLogger {
+            buffer: RefCell::new(LogBuffer::new(buffer)),
+            uart_filter: Cell::new(LevelFilter::Info),
+        }
+    }
+
+    pub fn register(self) {
+        unsafe {
+            LOGGER = Some(self);
+            log::set_logger(LOGGER.as_ref().unwrap())
+                .expect("global logger can only be initialized once");
+        }
+    }
+
+    pub unsafe fn get_logger() -> &'static mut Option<BufferLogger> {
+        &mut LOGGER
+    }
+
+    pub fn buffer<'a>(&'a self) -> Result<LogBufferRef<'a>, ()> {
+        self.buffer
+            .try_borrow_mut()
+            .map(LogBufferRef::new)
+            .map_err(|_| ())
+    }
+
+    pub fn uart_log_level(&self) -> LevelFilter {
+        self.uart_filter.get()
+    }
+
+    pub fn set_uart_log_level(&self, max_level: LevelFilter) {
+        self.uart_filter.set(max_level)
+    }
+}
+
+// required for impl Log
+unsafe impl Sync for BufferLogger {}
+
+impl Log for BufferLogger {
+    fn enabled(&self, _metadata: &log::Metadata) -> bool {
+        true
+    }
+
+    fn log(&self, record: &log::Record) {
+        if self.enabled(record.metadata()) {
+            let timestamp = unsafe {
+                GlobalTimer::get()
+            }.get_us();
+            let seconds   = timestamp / 1_000_000;
+            let micros    = timestamp % 1_000_000;
+
+            if let Ok(mut buffer) = self.buffer.try_borrow_mut() {
+                writeln!(buffer, "[{:6}.{:06}s] {:>5}({}): {}", seconds, micros,
+                         record.level(), record.target(), record.args()).unwrap();
+            }
+
+            if record.level() <= self.uart_log_level() {
+                println!("[{:6}.{:06}s] {:>5}({}): {}", seconds, micros,
+                         record.level(), record.target(), record.args());
+            }
+        }
+    }
+
+    fn flush(&self) {
+    }
+}
diff --git a/src/runtime/src/main.rs b/src/runtime/src/main.rs
index 4c0c4189..1bef8b79 100644
--- a/src/runtime/src/main.rs
+++ b/src/runtime/src/main.rs
@@ -9,7 +9,7 @@ extern crate alloc;
 use core::{cmp, str};
 use log::{info, warn};
 
-use libboard_zynq::{timer::GlobalTimer, time::Milliseconds, logger, devc, slcr};
+use libboard_zynq::{timer::GlobalTimer, time::Milliseconds, devc, slcr};
 use libsupport_zynq::ram;
 use libregister::RegisterW;
 use nb::block;
@@ -30,6 +30,7 @@ mod moninj;
 mod load_pl;
 mod eh_artiq;
 mod panic;
+mod logger;
 
 fn init_gateware() {
     // Set up PS->PL clocks
@@ -124,11 +125,19 @@ fn init_rtio(timer: GlobalTimer, cfg: &config::Config) {
     }
 }
 
+static mut LOG_BUFFER: [u8; 1<<17] = [0; 1<<17];
+
 #[no_mangle]
 pub fn main_core0() {
     let timer = GlobalTimer::start();
-    let _ = logger::init();
+
+    let buffer_logger = unsafe {
+        logger::BufferLogger::new(&mut LOG_BUFFER[..])
+    };
+    buffer_logger.set_uart_log_level(log::LevelFilter::Debug);
+    buffer_logger.register();
     log::set_max_level(log::LevelFilter::Debug);
+
     info!("NAR3/Zynq7000 starting...");
 
     ram::init_alloc_linker();