Add get-protocol-information command

This is necessary to support larger packet sizes for host protocol
ver.3.  The host previously didn't have any way to know how big a
packet the EC could accept / respond with (except on LPC, where the
size is determined by the I/O window).

BUG=chrome-os-partner:20257
BRANCH=none
TEST='ectool protoinfo' returns good info; on link,

  Protocol info:
    protocol versions: 2 3
    max request:   256 bytes
    max response:  256 bytes
    flags: 0x00000000

and on pit,

  Protocol info:
    protocol versions: 2 3
    max request:   544 bytes
    max response:  544 bytes
    flags: 0x00000001

Change-Id: Ic1e3831d9b4a96ffbf365c0d09b6023472de39a9
Signed-off-by: Randall Spangler <rspangler@chromium.org>
Reviewed-on: https://gerrit.chromium.org/gerrit/60703
Reviewed-by: Bill Richardson <wfrichar@chromium.org>

4 files changed, 118 insertions, 12 deletions

diff --git a/chip/lm4/lpc.c b/chip/lm4/lpc.c
index 8e2102b403..6648a56dad 100644
--- a/chip/lm4/lpc.c
+++ b/chip/lm4/lpc.c
@@ -849,3 +849,24 @@ static void lpc_tick(void)
 	task_trigger_irq(LM4_IRQ_LPC);
 }
 DECLARE_HOOK(HOOK_TICK, lpc_tick, HOOK_PRIO_DEFAULT);
+
+/**
+ * Get protocol information
+ */
+static int lpc_get_protocol_info(struct host_cmd_handler_args *args)
+{
+	struct ec_response_get_protocol_info *r = args->response;
+
+	memset(r, 0, sizeof(*r));
+	r->protocol_versions = (1 << 2) | (1 << 3);
+	r->max_request_packet_size = EC_LPC_HOST_PACKET_SIZE;
+	r->max_response_packet_size = EC_LPC_HOST_PACKET_SIZE;
+	r->flags = 0;
+
+	args->response_size = sizeof(*r);
+
+	return EC_SUCCESS;
+}
+DECLARE_HOST_COMMAND(EC_CMD_GET_PROTOCOL_INFO,
+		     lpc_get_protocol_info,
+		     EC_VER_MASK(0));
diff --git a/chip/stm32/spi.c b/chip/stm32/spi.c
index c2a6044da8..4f65820d9a 100644
--- a/chip/stm32/spi.c
+++ b/chip/stm32/spi.c
@@ -63,18 +63,15 @@ enum {
 	 * for a 1MHz clock which is as slow as we would reasonably want it.
 	 */
 	SPI_CMD_RX_TIMEOUT_US	= 8192,
-};
 
-/*
- * Our input and output buffers. These must be large enough for our largest
- * message, including protocol overhead.
- */
-static uint8_t out_msg[EC_HOST_PARAM_SIZE + SPI_MSG_PROTO_LEN];
-static uint8_t in_msg[EC_HOST_PARAM_SIZE + SPI_MSG_PROTO_LEN];
-static uint8_t active;
-static uint8_t enabled;
-static struct host_cmd_handler_args args;
-static struct host_packet spi_packet;
+	/*
+	 * Max data size for request/response packet.  This is big enough
+	 * to handle a request/respose header, flash write offset/size, and
+	 * 512 bytes of flash data.
+	 */
+	SPI_MAX_REQUEST_SIZE = 0x220,
+	SPI_MAX_RESPONSE_SIZE = 0x220,
+};
 
 /*
  * The AP blindly clocks back bytes over the SPI interface looking for the
@@ -93,6 +90,17 @@ static const uint8_t out_preamble[4] = {
 	SPI_MSG_HEADER_BYTE2,  /* This is the byte which matters */
 };
 
+/*
+ * Our input and output buffers. These must be large enough for our largest
+ * message, including protocol overhead.
+ */
+static uint8_t out_msg[SPI_MAX_RESPONSE_SIZE + sizeof(out_preamble)];
+static uint8_t in_msg[SPI_MAX_REQUEST_SIZE];
+static uint8_t active;
+static uint8_t enabled;
+static struct host_cmd_handler_args args;
+static struct host_packet spi_packet;
+
 /**
  * Wait until we have received a certain number of bytes
  *
@@ -228,7 +236,7 @@ static void setup_for_transaction(void)
 }
 
 /**
- * Called to indicate that a command has completed
+ * Called for V2 protocol to indicate that a command has completed
  *
  * Some commands can continue for a while. This function is called by
  * host_command when it completes.
@@ -450,3 +458,24 @@ static void spi_chipset_shutdown(void)
 }
 DECLARE_HOOK(HOOK_CHIPSET_SHUTDOWN, spi_chipset_shutdown, HOOK_PRIO_DEFAULT);
 DECLARE_HOOK(HOOK_CHIPSET_SUSPEND, spi_chipset_shutdown, HOOK_PRIO_DEFAULT);
+
+/**
+ * Get protocol information
+ */
+static int spi_get_protocol_info(struct host_cmd_handler_args *args)
+{
+	struct ec_response_get_protocol_info *r = args->response;
+
+	memset(r, 0, sizeof(*r));
+	r->protocol_versions = (1 << 2) | (1 << 3);
+	r->max_request_packet_size = SPI_MAX_REQUEST_SIZE;
+	r->max_response_packet_size = SPI_MAX_RESPONSE_SIZE;
+	r->flags = EC_PROTOCOL_INFO_IN_PROGRESS_SUPPORTED;
+
+	args->response_size = sizeof(*r);
+
+	return EC_SUCCESS;
+}
+DECLARE_HOST_COMMAND(EC_CMD_GET_PROTOCOL_INFO,
+		     spi_get_protocol_info,
+		     EC_VER_MASK(0));
diff --git a/include/ec_commands.h b/include/ec_commands.h
index 2eb0b7159c..0359bb1270 100644
--- a/include/ec_commands.h
+++ b/include/ec_commands.h
@@ -502,6 +502,29 @@ struct ec_response_test_protocol {
 	uint8_t buf[32];
 } __packed;
 
+/* Get prococol information */
+#define EC_CMD_GET_PROTOCOL_INFO	0x0b
+
+/* Flags for ec_response_get_protocol_info.flags */
+/* EC_RES_IN_PROGRESS may be returned if a command is slow */
+#define EC_PROTOCOL_INFO_IN_PROGRESS_SUPPORTED (1 << 0)
+
+struct ec_response_get_protocol_info {
+	/* Fields which exist if at least protocol version 3 supported */
+
+	/* Bitmask of protocol versions supported (1 << n means version n)*/
+	uint32_t protocol_versions;
+
+	/* Maximum request packet size, in bytes */
+	uint16_t max_request_packet_size;
+
+	/* Maximum response packet size, in bytes */
+	uint16_t max_response_packet_size;
+
+	/* Flags; see EC_PROTOCOL_INFO_* */
+	uint32_t flags;
+} __packed;
+
 /*****************************************************************************/
 /* Flash commands */
 
diff --git a/util/ectool.c b/util/ectool.c
index 953b5b9a6d..39e49d16f5 100644
--- a/util/ectool.c
+++ b/util/ectool.c
@@ -108,6 +108,8 @@ const char help_str[] =
 	"      Rapidly write bytes to port 80\n"
 	"  powerinfo\n"
 	"	Prints power-related information\n"
+	"  protoinfo\n"
+	"       Prints EC host protocol information\n"
 	"  pstoreinfo\n"
 	"      Prints information on the EC host persistent storage\n"
 	"  pstoreread <offset> <size> <outfile>\n"
@@ -2561,6 +2563,36 @@ int cmd_chipinfo(int argc, char *argv[])
 	return 0;
 }
 
+int cmd_proto_info(int argc, char *argv[])
+{
+	struct ec_response_get_protocol_info info;
+	int rv;
+	int i;
+
+	printf("Protocol info:\n");
+
+	rv = ec_command(EC_CMD_GET_PROTOCOL_INFO, 0, NULL, 0,
+			&info, sizeof(info));
+	if (rv < 0) {
+		fprintf(stderr, "Protocol info unavailable.  EC probably only "
+				"supports protocol version 2.\n");
+		return rv;
+	}
+
+	printf("  protocol versions:");
+	for (i = 0; i < 32; i++) {
+		if (info.protocol_versions & (1 << i))
+			printf(" %d", i);
+	}
+	printf("\n");
+
+	printf("  max request:  %4d bytes\n", info.max_request_packet_size);
+	printf("  max response: %4d bytes\n", info.max_response_packet_size);
+	printf("  flags: 0x%08x\n", info.flags);
+	if (info.flags & EC_PROTOCOL_INFO_IN_PROGRESS_SUPPORTED)
+		printf("    EC_RES_IN_PROGRESS supported\n");
+	return 0;
+}
 
 static int ec_hash_help(const char *cmd)
 {
@@ -3049,6 +3081,7 @@ const struct command commands[] = {
 	{"keyscan", cmd_keyscan},
 	{"panicinfo", cmd_panic_info},
 	{"powerinfo", cmd_power_info},
+	{"protoinfo", cmd_proto_info},
 	{"pstoreinfo", cmd_pstore_info},
 	{"pstoreread", cmd_pstore_read},
 	{"pstorewrite", cmd_pstore_write},