Simplify host event processing

Now both copies of the event state live in host_event_commands.c, and
lpc / memmap just shadows the main copy.

BUG=chrome-os-partner:11172
TEST=manual

Boot system.  should see events 0x2000, 0x80, 0x08 get set and then cleared.

At U-boot prompt, type on keyboard.  Should set event 0x1000 get set,
but only on the first keypress (because U-boot doesn't consume that
event).

Then from EC console,
hostevent clear 0x1000 -> see event 0x1000 clear
hostevent clear 0x1000 -> no debug output (it's already clear)
hostevent clearb 0x1000 -> see event copy B 0x1000 clear
hostevent clearb 0x1000 -> no debug output (copy B is already clear)

Change-Id: I855c035865649ba1490cd9027157d5bcdcc9895f
Signed-off-by: Randall Spangler <rspangler@chromium.org>
Reviewed-on: https://gerrit.chromium.org/gerrit/27321

1 files changed, 36 insertions, 14 deletions

diff --git a/common/host_event_commands.c b/common/host_event_commands.c
index b4a161068a..670212c430 100644
--- a/common/host_event_commands.c
+++ b/common/host_event_commands.c
@@ -12,41 +12,59 @@
 #include "lpc.h"
 #include "util.h"
 
-/* Copy B of current events mask.
+/* Console output macros */
+#define CPUTS(outstr) cputs(CC_EVENTS, outstr)
+#define CPRINTF(format, args...) cprintf(CC_EVENTS, format, ## args)
+
+/*
+ * Maintain two copies of the events that are set.
+ *
+ * The primary copy is mirrored in mapped memory and used to trigger interrupts
+ * on the host via ACPI/SCI/SMI/GPIO.
  *
- * This is separate from the main copy, which affects ACPI/SCI/SMI/wake.
+ * The secondary (B) copy is used to track events at a non-interrupt level (for
+ * example, so a user-level process can find out what events have happened
+ * since the last call, even though a kernel-level process is consuming events
+ * from the first copy).
  *
- * Setting an event sets both copies.  Copies are cleared separately. */
+ * Setting an event sets both copies.  Copies are cleared separately.
+ */
+static uint32_t events;
 static uint32_t events_copy_b;
 
 uint32_t host_get_events(void)
 {
-#ifdef CONFIG_LPC
-	return lpc_get_host_events();
-#else
-	uint32_t *mapped_raw_events =
-		(uint32_t *)host_get_memmap(EC_MEMMAP_HOST_EVENTS);
-	return *mapped_raw_events;
-#endif
+	return events;
 }
 
 void host_set_events(uint32_t mask)
 {
+	/* Only print if something's about to change */
+	if ((events & mask) != mask || (events_copy_b & mask) != mask)
+		CPRINTF("[%T event set 0x%08x]\n", mask);
+
+	atomic_or(&events, mask);
 	atomic_or(&events_copy_b, mask);
 
 #ifdef CONFIG_LPC
-	lpc_set_host_events(mask);
+	lpc_set_host_event_state(events);
 #else
-	*(uint32_t *)host_get_memmap(EC_MEMMAP_HOST_EVENTS) |= mask;
+	*(uint32_t *)host_get_memmap(EC_MEMMAP_HOST_EVENTS) = events;
 #endif
 }
 
 void host_clear_events(uint32_t mask)
 {
+	/* Only print if something's about to change */
+	if (events & mask)
+		CPRINTF("[%T event clear 0x%08x]\n", mask);
+
+	atomic_clear(&events, mask);
+
 #ifdef CONFIG_LPC
-	lpc_clear_host_events(mask);
+	lpc_set_host_event_state(events);
 #else
-	*(uint32_t *)host_get_memmap(EC_MEMMAP_HOST_EVENTS) &= ~mask;
+	*(uint32_t *)host_get_memmap(EC_MEMMAP_HOST_EVENTS) = events;
 #endif
 }
 
@@ -58,6 +76,10 @@ void host_clear_events(uint32_t mask)
  */
 static void host_clear_events_b(uint32_t mask)
 {
+	/* Only print if something's about to change */
+	if (events_copy_b & mask)
+		CPRINTF("[%T event clear B 0x%08x]\n", mask);
+
 	atomic_clear(&events_copy_b, mask);
 }