pd: add sending read info VDM every time source is plugged in

Every time a type-C source is plugged in, send a special VDM to
read device info. Device info will contain RW Hash (sha1), a
unique hardware descriptor (USB_PD_HARDWARE_DEVICE_ID), a
software version number just for debugging (USB_PD_DBG_SW_VERSION),
and a flag for if the device is in RW. This feature is off by
default and can be turned on by defining
CONFIG_USB_PD_READ_INFO_ON_CONNECT, currently defined for samus
and ryu only.

Renamed the read RW_HASH VDM to READ_INFO since it now returns
more than just the hash.

When device info is received, we store the RW hash. In the future
we will use this to check if device needs an update.

BUG=chrome-os-partner:31361
BRANCH=none
TEST=load onto a samus and a zinger. test when you attach zinger
we send a VDM, and we get device info printed to console. also
use "pd 0 hash" to query last hash received.

Change-Id: I0ca57651cf8506ea738b080a6cf8e7b020ef8724
Signed-off-by: Alec Berg <alecaberg@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/213832
Reviewed-by: Randall Spangler <rspangler@chromium.org>
Reviewed-by: Todd Broch <tbroch@chromium.org>

9 files changed, 87 insertions, 24 deletions

diff --git a/board/fruitpie/usb_pd_policy.c b/board/fruitpie/usb_pd_policy.c
index 3292a80a77..0a4b1be7ee 100644
--- a/board/fruitpie/usb_pd_policy.c
+++ b/board/fruitpie/usb_pd_policy.c
@@ -139,7 +139,6 @@ int pd_board_checks(void)
 int pd_custom_vdm(int port, int cnt, uint32_t *payload, uint32_t **rpayload)
 {
 	int cmd = PD_VDO_CMD(payload[0]);
-	int i;
 	ccprintf("VDM/%d [%d] %08x\n", cnt, cmd, payload[0]);
 
 	/* make sure we have some payload */
@@ -152,12 +151,17 @@ int pd_custom_vdm(int port, int cnt, uint32_t *payload, uint32_t **rpayload)
 		*(payload + cnt - 1) = 0;
 		ccprintf("version: %s\n", (char *)(payload+1));
 		break;
-	case VDO_CMD_RW_HASH:
-		ccprintf("RW Hash: ");
-		payload++; /* skip cmd */
-		for (i = 0; i < cnt - 1; i++)
-			ccprintf("%08x ", *payload++);
-		ccprintf("\n");
+	case VDO_CMD_READ_INFO:
+		/* copy hash */
+		if (cnt >= 6)
+			pd_dev_store_rw_hash(port, payload + 1);
+
+		/* if last word is present, it contains lots of info */
+		if (cnt == 7)
+			ccprintf("Dev:%d SW:%d RW:%d\n",
+				 VDO_INFO_HW_DEV_ID(payload[6]),
+				 VDO_INFO_SW_DBG_VER(payload[6]),
+				 VDO_INFO_IS_RW(payload[6]));
 		break;
 	}
 
diff --git a/board/ryu/board.h b/board/ryu/board.h
index 768f71fb1e..7d3b9f5fc3 100644
--- a/board/ryu/board.h
+++ b/board/ryu/board.h
@@ -24,6 +24,7 @@
 #define CONFIG_USB_PD_DUAL_ROLE
 #define CONFIG_USB_PD_FLASH_ERASE_CHECK
 #define CONFIG_USB_PD_INTERNAL_COMP
+#define CONFIG_USB_PD_READ_INFO_ON_CONNECT
 #define CONFIG_USBC_SS_MUX
 #define CONFIG_ADC
 #define CONFIG_HW_CRC
diff --git a/board/samus_pd/board.h b/board/samus_pd/board.h
index 87cef022b9..4cc58a56e4 100644
--- a/board/samus_pd/board.h
+++ b/board/samus_pd/board.h
@@ -25,6 +25,7 @@
 #define CONFIG_USB_PD_DUAL_ROLE
 #define CONFIG_USB_PD_FLASH_ERASE_CHECK
 #define CONFIG_USB_PD_INTERNAL_COMP
+#define CONFIG_USB_PD_READ_INFO_ON_CONNECT
 #define CONFIG_USBC_SS_MUX
 #define CONFIG_ADC
 #define CONFIG_HW_CRC
diff --git a/board/samus_pd/usb_pd_policy.c b/board/samus_pd/usb_pd_policy.c
index 7b56d12435..bf24b2eb07 100644
--- a/board/samus_pd/usb_pd_policy.c
+++ b/board/samus_pd/usb_pd_policy.c
@@ -154,7 +154,6 @@ int pd_board_checks(void)
 int pd_custom_vdm(int port, int cnt, uint32_t *payload, uint32_t **rpayload)
 {
 	int cmd = PD_VDO_CMD(payload[0]);
-	int i;
 	ccprintf("VDM/%d [%d] %08x\n", cnt, cmd, payload[0]);
 
 	/* make sure we have some payload */
@@ -167,12 +166,17 @@ int pd_custom_vdm(int port, int cnt, uint32_t *payload, uint32_t **rpayload)
 		*(payload + cnt - 1) = 0;
 		ccprintf("version: %s\n", (char *)(payload+1));
 		break;
-	case VDO_CMD_RW_HASH:
-		ccprintf("RW Hash: ");
-		payload++; /* skip cmd */
-		for (i = 0; i < cnt - 1; i++)
-			ccprintf("%08x ", *payload++);
-		ccprintf("\n");
+	case VDO_CMD_READ_INFO:
+		/* copy hash */
+		if (cnt >= 6)
+			pd_dev_store_rw_hash(port, payload + 1);
+
+		/* if last word is present, it contains lots of info */
+		if (cnt == 7)
+			ccprintf("Dev:%d SW:%d RW:%d\n",
+				 VDO_INFO_HW_DEV_ID(payload[6]),
+				 VDO_INFO_SW_DBG_VER(payload[6]),
+				 VDO_INFO_IS_RW(payload[6]));
 		break;
 	case VDO_CMD_CURRENT:
 		ccprintf("Current: %dmA\n", payload[1]);
diff --git a/board/zinger/board.h b/board/zinger/board.h
index ead71fb711..f3a0d3dc5f 100644
--- a/board/zinger/board.h
+++ b/board/zinger/board.h
@@ -42,6 +42,10 @@
 #define UARTN CONFIG_UART_CONSOLE
 #define UARTN_BASE STM32_USART_BASE(CONFIG_UART_CONSOLE)
 
+/* USB PD ChromeOS VDM information */
+#define USB_PD_HARDWARE_DEVICE_ID 1
+#define USB_PD_DBG_SW_VERSION     255
+
 #ifndef __ASSEMBLER__
 
 #include "common.h"
diff --git a/board/zinger/usb_pd_policy.c b/board/zinger/usb_pd_policy.c
index a4fcc38fe1..591021bb56 100644
--- a/board/zinger/usb_pd_policy.c
+++ b/board/zinger/usb_pd_policy.c
@@ -369,10 +369,16 @@ int pd_custom_vdm(int port, int cnt, uint32_t *payload, uint32_t **rpayload)
 		pd_power_supply_reset(0);
 		cpu_reset();
 		break;
-	case VDO_CMD_RW_HASH:
+	case VDO_CMD_READ_INFO:
 		hash = flash_hash_rw();
+		/* copy hash into response */
 		memcpy(payload + 1, hash, SHA1_DIGEST_SIZE);
-		rsize = 6;
+		/* copy other info into response */
+		payload[SHA1_DIGEST_SIZE/4 + 1] = VDO_INFO(
+						USB_PD_HARDWARE_DEVICE_ID,
+						USB_PD_DBG_SW_VERSION,
+						!is_ro_mode());
+		rsize = 7;
 		break;
 	case VDO_CMD_FLASH_ERASE:
 		/* do not kill the code under our feet */
diff --git a/common/usb_pd_protocol.c b/common/usb_pd_protocol.c
index 263c9b63e0..387ea20e82 100644
--- a/common/usb_pd_protocol.c
+++ b/common/usb_pd_protocol.c
@@ -13,6 +13,7 @@
 #include "hooks.h"
 #include "host_command.h"
 #include "registers.h"
+#include "sha1.h"
 #include "task.h"
 #include "timer.h"
 #include "util.h"
@@ -220,6 +221,9 @@ static struct pd_protocol {
 	/* next Vendor Defined Message to send */
 	uint32_t vdo_data[VDO_MAX_SIZE];
 	uint8_t vdo_count;
+
+	/* Attached ChromeOS device RW hash */
+	uint32_t dev_rw_hash[SHA1_DIGEST_SIZE/4];
 } pd[PD_PORT_COUNT];
 
 /*
@@ -1019,6 +1023,11 @@ static void pd_vdm_send_state_machine(int port)
 	}
 }
 
+void pd_dev_store_rw_hash(int port, uint32_t *rw_hash)
+{
+	memcpy(pd[port].dev_rw_hash, rw_hash, SHA1_DIGEST_SIZE);
+}
+
 #ifdef CONFIG_USB_PD_DUAL_ROLE
 void pd_set_dual_role(enum pd_dual_role_states state)
 {
@@ -1276,6 +1285,11 @@ void pd_task(void)
 						!(cc1_volt >= PD_SNK_VA);
 					pd_select_polarity(port,
 							   pd[port].polarity);
+#ifdef CONFIG_USB_PD_READ_INFO_ON_CONNECT
+					/* Send google VDM to read info */
+					pd_send_vdm(port, USB_VID_GOOGLE,
+						VDO_CMD_READ_INFO, NULL, 0);
+#endif
 					set_state(port, PD_STATE_SNK_DISCOVERY);
 					timeout = 10*MSEC;
 				}
@@ -1493,9 +1507,9 @@ static int remote_flashing(int argc, char **argv)
 		cmd = VDO_CMD_FLASH_HASH;
 		cnt = argc;
 		ccprintf("HASH ...");
-	} else if (!strcasecmp(argv[3], "rw_hash")) {
-		cmd = VDO_CMD_RW_HASH;
-		ccprintf("RW HASH...");
+	} else if (!strcasecmp(argv[3], "info")) {
+		cmd = VDO_CMD_READ_INFO;
+		ccprintf("INFO...");
 	} else if (!strcasecmp(argv[3], "version")) {
 		cmd = VDO_CMD_VERSION;
 		ccprintf("VERSION...");
@@ -1602,6 +1616,11 @@ static int command_pd(int argc, char **argv)
 	} else if (!strncasecmp(argv[2], "hard", 4)) {
 		set_state(port, PD_STATE_HARD_RESET);
 		task_wake(PORT_TO_TASK_ID(port));
+	} else if (!strncasecmp(argv[2], "hash", 4)) {
+		int i;
+		for (i = 0; i < SHA1_DIGEST_SIZE / 4; i++)
+			ccprintf("%08x ", pd[port].dev_rw_hash[i]);
+		ccprintf("\n");
 	} else if (!strncasecmp(argv[2], "soft", 4)) {
 		execute_soft_reset(port);
 		send_control(port, PD_CTRL_SOFT_RESET);
@@ -1690,7 +1709,8 @@ static int command_pd(int argc, char **argv)
 DECLARE_CONSOLE_COMMAND(pd, command_pd,
 			"<port> "
 			"[tx|bist|charger|dev|dump|dualrole|enable"
-			"|soft|hard|clock|ping|state|vdm [ping | curr]]",
+			"|soft|hash|hard|clock|ping|state"
+			"|vdm [ping | curr]]",
 			"USB PD",
 			NULL);
 
diff --git a/include/config.h b/include/config.h
index 1221a6f6bc..609d0943b2 100644
--- a/include/config.h
+++ b/include/config.h
@@ -941,6 +941,9 @@
 /* Define if this board can act as a dual-role PD port (source and sink) */
 #undef CONFIG_USB_PD_DUAL_ROLE
 
+/* Dynamic USB PD source capability */
+#undef CONFIG_USB_PD_DYNAMIC_SRC_CAP
+
 /* Check whether PD is the sole power source before flash erase operation */
 #undef CONFIG_USB_PD_FLASH_ERASE_CHECK
 
@@ -950,12 +953,12 @@
 /* Define if using internal comparator for PD receive */
 #undef CONFIG_USB_PD_INTERNAL_COMP
 
+/* Define to have PD state machine send read info VDM on connection */
+#undef CONFIG_USB_PD_READ_INFO_ON_CONNECT
+
 /* USB PD transmit uses SPI master */
 #undef CONFIG_USB_PD_TX_USES_SPI_MASTER
 
-/* Dynamic USB PD source capability */
-#undef CONFIG_USB_PD_DYNAMIC_SRC_CAP
-
 /* Support for USB type-c superspeed mux */
 #undef CONFIG_USBC_SS_MUX
 
diff --git a/include/usb_pd.h b/include/usb_pd.h
index 83fee88cf0..4a9376a369 100644
--- a/include/usb_pd.h
+++ b/include/usb_pd.h
@@ -122,7 +122,7 @@ enum pd_errors {
 
 /* ChromeOS specific commands */
 #define VDO_CMD_VERSION      VDO_CMD_VENDOR(0)
-#define VDO_CMD_RW_HASH      VDO_CMD_VENDOR(2)
+#define VDO_CMD_READ_INFO    VDO_CMD_VENDOR(2)
 #define VDO_CMD_REBOOT       VDO_CMD_VENDOR(5)
 #define VDO_CMD_FLASH_ERASE  VDO_CMD_VENDOR(6)
 #define VDO_CMD_FLASH_WRITE  VDO_CMD_VENDOR(7)
@@ -133,6 +133,18 @@ enum pd_errors {
 #define PD_VDO_VID(vdo) ((vdo) >> 16)
 #define PD_VDO_CMD(vdo) ((vdo) & 0x1f)
 
+/*
+ * ChromeOS specific VDO_CMD_READ_INFO responds with device info including:
+ * RW Hash: sha1 of RW hash (20 bytes)
+ * HW Device ID: unique descriptor for each ChromeOS model (2 bytes)
+ * SW Debug Version: Software version useful for debugging (1 byte)
+ * IS RW: True if currently in RW, False otherwise (1 bit)
+ */
+#define VDO_INFO(id, ver, is_rw) ((id) << 16 | (ver) << 8 | (is_rw))
+#define VDO_INFO_HW_DEV_ID(x)    ((x) >> 16)
+#define VDO_INFO_SW_DBG_VER(x)   (((x) >> 8) & 0xff)
+#define VDO_INFO_IS_RW(x)        ((x) & 1)
+
 /* USB Vendor ID assigned to Google Inc. */
 #define USB_VID_GOOGLE 0x18d1
 
@@ -293,6 +305,14 @@ int pd_board_checks(void);
 int pd_custom_vdm(int port, int cnt, uint32_t *payload, uint32_t **rpayload);
 
 /**
+ * Store RW hash of device
+ *
+ * @param port     USB-C port number
+ * @param rw_hash  pointer to sha1 rw_hash
+ */
+void pd_dev_store_rw_hash(int port, uint32_t *rw_hash);
+
+/**
  * Send Vendor Defined Message
  *
  * @param port     USB-C port number