[lib][io] Capture early Trusty boot logs
Capture early boot logs and then send them to each print
callback that is registered. This allows early Trusty boot
logs to be seen without requiring uart.
Bug: 221868606
Test: boot, see logs
Change-Id: I40ab533d475fe3500271dc867f152b9356fae456
diff --git a/lib/io/console.c b/lib/io/console.c
index 4c6eaed..fa50450 100644
--- a/lib/io/console.c
+++ b/lib/io/console.c
@@ -74,6 +74,35 @@
static uint8_t console_cbuf_buf[CONSOLE_BUF_LEN];
#endif // CONSOLE_HAS_INPUT_BUFFER
+#if EARLY_LOG_BUFFER_SIZE
+/*
+ * Very early boot logs are captured in a buffer, and then dumped to the
+ * first print callback that is registered
+ */
+
+static char early_log_buffer[EARLY_LOG_BUFFER_SIZE];
+static char* early_log_writeptr = early_log_buffer;
+static char* early_log_end = early_log_buffer + sizeof(early_log_buffer);
+
+static void early_log_print(const char *str, size_t len)
+{
+ size_t remaining = early_log_end - early_log_writeptr;
+ if (remaining == 0) {
+ return;
+ }
+ if (len > remaining) {
+ /*
+ * Don't bother with partial lines, just mark the buffer as full
+ * and drop all further logs
+ */
+ early_log_end = early_log_writeptr;
+ return;
+ }
+ memcpy(early_log_writeptr, str, len);
+ early_log_writeptr += len;
+}
+#endif
+
/* print lock must be held when invoking out, outs, outc */
static void out_count(const char *str, size_t len)
{
@@ -84,6 +113,17 @@
DEBUG_ASSERT(need_lock || lock_held_by == arch_curr_cpu_num());
+ /* copy to the early log buffer if configured */
+#if EARLY_LOG_BUFFER_SIZE
+ if (need_lock) {
+ spin_lock_save(&print_spin_lock, &state, PRINT_LOCK_FLAGS);
+ }
+ early_log_print(str, len);
+ if (need_lock) {
+ spin_unlock_restore(&print_spin_lock, state, PRINT_LOCK_FLAGS);
+ }
+#endif
+
/* print to any registered loggers */
if (!list_is_empty(&print_callbacks)) {
if (need_lock) {
@@ -174,6 +214,17 @@
spin_lock_saved_state_t state;
spin_lock_save(&print_spin_lock, &state, PRINT_LOCK_FLAGS);
+#if EARLY_LOG_BUFFER_SIZE
+ size_t early_log_len = early_log_writeptr - early_log_buffer;
+ if (early_log_len) {
+ if (cb->print) {
+ cb->print(cb, early_log_buffer, early_log_len);
+ }
+ if (cb->commit) {
+ cb->commit(cb);
+ }
+ }
+#endif
list_add_head(&print_callbacks, &cb->entry);
spin_unlock_restore(&print_spin_lock, state, PRINT_LOCK_FLAGS);
diff --git a/lib/io/rules.mk b/lib/io/rules.mk
index 553ac55..4a2e539 100644
--- a/lib/io/rules.mk
+++ b/lib/io/rules.mk
@@ -13,6 +13,12 @@
MODULE_DEFINES += CONSOLE_CALLBACK_DISABLES_SERIAL=1
endif
+# The size of the buffer to capture early boot logs in, which will
+# then be dumped to the first print callback to register.
+# Set to 0 to disable.
+CONSOLE_EARLY_LOG_BUFFER_SIZE ?= 4096
+MODULE_DEFINES += EARLY_LOG_BUFFER_SIZE=$(CONSOLE_EARLY_LOG_BUFFER_SIZE)
+
endif
MODULE_SRCS += \
