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>

1 files changed, 41 insertions, 12 deletions

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));