g: tweak usart queuing for stream signing

Guarded by CONFIG_STREAM_SIGNING
Comes at 10K cost in SRAM
Used by nm50

Signed-off-by: mschilder@google.com
BRANCH=cr50
BUG=none
TEST=sign nm50 target dump_state 115200 output w/o overruns

Change-Id: I4db2dec4de8afbeba68d1bc72f43a91fc134ff85
Reviewed-on: https://chromium-review.googlesource.com/823264
Commit-Ready: Marius Schilder <mschilder@chromium.org>
Tested-by: Marius Schilder <mschilder@chromium.org>
Reviewed-by: Marius Schilder <mschilder@chromium.org>
Reviewed-by: Vadim Bendebury <vbendeb@chromium.org>

2 files changed, 32 insertions, 4 deletions

diff --git a/chip/g/usart.c b/chip/g/usart.c
index 598b4d4ed9..667a891e42 100644
--- a/chip/g/usart.c
+++ b/chip/g/usart.c
@@ -16,6 +16,19 @@
 defined(SECTION_IS_RO)))
 #define QUEUE_SIZE 64
 
+#ifdef CONFIG_STREAM_SIGNATURE
+/*
+ * When signing over streaming data, up the relevant queue sizes.
+ */
+#define QUEUE_SIZE_SIG_IN  1024
+#define QUEUE_SIZE_USB_IN  8192
+#define QUEUE_SIZE_UART_IN 1024
+#else
+#define QUEUE_SIZE_SIG_IN  QUEUE_SIZE
+#define QUEUE_SIZE_USB_IN  QUEUE_SIZE
+#define QUEUE_SIZE_UART_IN QUEUE_SIZE
+#endif
+
 
 #ifdef CONFIG_STREAM_USART1
 struct usb_stream_config const ap_usb;
@@ -34,9 +47,11 @@ struct usart_config const ap_uart;
  */
 struct signer_config const sig;
 static struct queue const ap_uart_output =
-	QUEUE_DIRECT(QUEUE_SIZE, uint8_t, ap_uart.producer, sig.consumer);
+	QUEUE_DIRECT(QUEUE_SIZE_SIG_IN, uint8_t, ap_uart.producer,
+		     sig.consumer);
 static struct queue const sig_to_usb =
-	QUEUE_DIRECT(QUEUE_SIZE, uint8_t, sig.producer, ap_usb.consumer);
+	QUEUE_DIRECT(QUEUE_SIZE_USB_IN, uint8_t, sig.producer,
+		     ap_usb.consumer);
 
 SIGNER_CONFIG(sig, stream_uart, sig_to_usb, ap_uart_output);
 
@@ -46,7 +61,8 @@ static struct queue const ap_uart_output =
 #endif
 
 static struct queue const ap_usb_to_uart =
-	QUEUE_DIRECT(QUEUE_SIZE, uint8_t, ap_usb.producer, ap_uart.consumer);
+	QUEUE_DIRECT(QUEUE_SIZE_UART_IN, uint8_t, ap_usb.producer,
+		     ap_uart.consumer);
 
 /*
  * AP UART data is sent to the ap_uart_output queue, and received from
diff --git a/chip/g/usart.h b/chip/g/usart.h
index 133dc7a3af..0be7a920bb 100644
--- a/chip/g/usart.h
+++ b/chip/g/usart.h
@@ -7,10 +7,22 @@
 #include "producer.h"
 #include "registers.h"
 #include "task.h"
+#include "board.h"
 
 #ifndef __CROS_FORWARD_UART_H
 #define __CROS_FORWARD_UART_H
 
+#ifdef CONFIG_STREAM_SIGNATURE
+/*
+ * When configured for signing over streaming data, call the consumer handler
+ * directly to help avoid incoming uart overruns.
+ * Note this will run under interrupt handler so consumer beware.
+ */
+#define CONFIGURE_INTERRUPTS__rx_int(NAME) send_data_to_usb(&NAME)
+#else
+#define CONFIGURE_INTERRUPTS__rx_int(NAME) hook_call_deferred(NAME.deferred, 0)
+#endif
+
 struct usart_config {
 	int uart;
 
@@ -43,7 +55,7 @@ extern struct producer_ops const uart_producer_ops;
 		GR_UART_ISTATECLR(NAME.uart) =				\
 			GC_UART_ISTATECLR_RX_MASK;			\
 		/* Read input FIFO until empty */			\
-		hook_call_deferred(NAME.deferred, 0);			\
+		CONFIGURE_INTERRUPTS__rx_int(NAME);			\
 	}