pd: Re-factor common flash vdms.

CL to migrate the flashing VDMs from zinger's custom vdm to
common/usb_pd_flash.c such that other updateable type-C devices can
share.

Additionally adds gaskets to call standard runtime flashing facilities
for USB-PD devices using it.

Signed-off-by: Todd Broch <tbroch@chromium.org>

BRANCH=samus
BUG=chrome-os-partner:31192,chrome-os-partner:31193
TEST=manual,

Try following:
    1. From samus_pd console w/ zinger in port 1

    pd 1 flash version
    pd 1 flash reboot
    pd 1 flash info

    2. From samus linux prompt  w/ zinger in port 1

    ectool --name cros_pd flashpd 1 1 <zinger RW payload>

    Reading 16384 bytes from
    /usr/local/zinger_v1.1.2528-d809e42.ec.RW.bin...
    Erasing expected RW hash
    Rebooting
    Erasing RW flash
    Writing RW flash
    Rebooting PD into new RW
    Complete

    3. Repeat 1&2 above on hoho & dingdong.

Change-Id: I018055fa9de128f937c57debdc21dea026137bcf
Reviewed-on: https://chromium-review.googlesource.com/231835
Reviewed-by: Vincent Palatin <vpalatin@chromium.org>
Reviewed-by: Alec Berg <alecaberg@chromium.org>
Tested-by: Todd Broch <tbroch@chromium.org>
Commit-Queue: Todd Broch <tbroch@chromium.org>

11 files changed, 163 insertions, 165 deletions

diff --git a/board/dingdong/usb_pd_policy.c b/board/dingdong/usb_pd_policy.c
index a09a432492..2a3c027e61 100644
--- a/board/dingdong/usb_pd_policy.c
+++ b/board/dingdong/usb_pd_policy.c
@@ -287,23 +287,18 @@ static int pd_custom_vdm(int port, int cnt, uint32_t *payload,
 			 uint32_t **rpayload)
 {
 	int cmd = PD_VDO_CMD(payload[0]);
-	int rsize = 1;
+	int rsize;
+
+	if (PD_VDO_VID(payload[0]) != USB_VID_GOOGLE || !gfu_mode)
+		return 0;
+
 	CPRINTF("VDM/%d [%d] %08x\n", cnt, cmd, payload[0]);
 
 	*rpayload = payload;
-	switch (cmd) {
-	case VDO_CMD_VERSION:
-		memcpy(payload + 1, &version_data.version, 24);
-		rsize = 7;
-		break;
-	case VDO_CMD_READ_INFO:
-		/* copy info into response */
-		pd_get_info(payload + 1);
-		rsize = 7;
-		break;
-	default:
-		rsize = 0;
-	}
+
+	rsize = pd_custom_flash_vdm(port, cnt, payload);
+	if (!rsize)
+		return 0;
 
 	CPRINTS("DONE");
 	/* respond (positively) to the request */
diff --git a/board/hoho/usb_pd_policy.c b/board/hoho/usb_pd_policy.c
index 50792a0e68..c9525f2ebe 100644
--- a/board/hoho/usb_pd_policy.c
+++ b/board/hoho/usb_pd_policy.c
@@ -286,23 +286,18 @@ static int pd_custom_vdm(int port, int cnt, uint32_t *payload,
 			 uint32_t **rpayload)
 {
 	int cmd = PD_VDO_CMD(payload[0]);
-	int rsize = 1;
+	int rsize;
+
+	if (PD_VDO_VID(payload[0]) != USB_VID_GOOGLE || !gfu_mode)
+		return 0;
+
 	CPRINTF("VDM/%d [%d] %08x\n", cnt, cmd, payload[0]);
 
 	*rpayload = payload;
-	switch (cmd) {
-	case VDO_CMD_VERSION:
-		memcpy(payload + 1, &version_data.version, 24);
-		rsize = 7;
-		break;
-	case VDO_CMD_READ_INFO:
-		/* copy info into response */
-		pd_get_info(payload + 1);
-		rsize = 7;
-		break;
-	default:
-		rsize = 0;
-	}
+
+	rsize = pd_custom_flash_vdm(port, cnt, payload);
+	if (!rsize)
+		return 0;
 
 	CPRINTS("DONE");
 	/* respond (positively) to the request */
diff --git a/board/zinger/board.c b/board/zinger/board.c
index 5dcbef04fb..3ea9850015 100644
--- a/board/zinger/board.c
+++ b/board/zinger/board.c
@@ -9,6 +9,7 @@
 #include "registers.h"
 #include "rsa.h"
 #include "sha256.h"
+#include "system.h"
 #include "task.h"
 #include "usb_pd.h"
 #include "util.h"
@@ -23,10 +24,6 @@ static const void *rw_sig = (void *)CONFIG_FLASH_BASE + CONFIG_FW_RW_OFF
 /* Large 768-Byte buffer for RSA computation : could be re-use afterwards... */
 static uint32_t rsa_workbuf[3 * RSANUMWORDS];
 
-static uint8_t *rw_hash;
-static uint8_t rw_flash_changed;
-static uint32_t info_data[6];
-
 extern void pd_rx_handler(void);
 
 /* RW firmware reset vector */
@@ -60,12 +57,16 @@ int is_ro_mode(void)
 static int check_rw_valid(void)
 {
 	int good;
+	void *rw_hash;
 
 	/* Check if we have a RW firmware flashed */
 	if (*rw_rst == 0xffffffff)
 		return 0;
 
-	good = rsa_verify(&pkey, (void *)rw_sig, (void *)rw_hash, rsa_workbuf);
+	/* calculate hash of RW */
+	rw_hash = flash_hash_rw();
+
+	good = rsa_verify(&pkey, (void *)rw_sig, rw_hash, rsa_workbuf);
 	if (!good) {
 		debug_printf("RSA verify FAILED\n");
 		return 0;
@@ -74,30 +75,6 @@ static int check_rw_valid(void)
 	return 1;
 }
 
-uint32_t *board_get_info(void)
-{
-	if (rw_flash_changed) {
-		/* re-calculate RW hash */
-		rw_hash = flash_hash_rw();
-		rw_flash_changed = 0;
-	}
-
-	/* copy first 20 bytes of RW hash */
-	memcpy(info_data, rw_hash, 5 * sizeof(uint32_t));
-
-	/* copy other info into data msg */
-	info_data[5] = VDO_INFO(CONFIG_USB_PD_HW_DEV_ID_BOARD_MAJOR,
-				CONFIG_USB_PD_HW_DEV_ID_BOARD_MINOR,
-				ver_get_numcommits(), !is_ro_mode());
-
-	return info_data;
-}
-
-void board_rw_contents_change(void)
-{
-	rw_flash_changed = 1;
-}
-
 extern void pd_task(void);
 
 int main(void)
@@ -106,9 +83,6 @@ int main(void)
 	debug_printf("Power supply started ... %s\n",
 		is_ro_mode() ? "RO" : "RW");
 
-	/* calculate hash of RW */
-	rw_hash = flash_hash_rw();
-
 	/* Verify RW firmware and use it if valid */
 	if (is_ro_mode() && check_rw_valid())
 		jump_to_rw();
@@ -118,6 +92,6 @@ int main(void)
 
 	debug_printf("background loop exited !\n");
 	/* we should never reach that point */
-	cpu_reset();
+	system_reset(0);
 	return 0;
 }
diff --git a/board/zinger/board.h b/board/zinger/board.h
index 8d7dcd4268..79d60514eb 100644
--- a/board/zinger/board.h
+++ b/board/zinger/board.h
@@ -109,13 +109,6 @@ int32_t get_rtc_diff(uint32_t rtc0, uint32_t rtc0ss,
 		     uint32_t rtc1, uint32_t rtc1ss);
 void __enter_hibernate(uint32_t seconds, uint32_t microseconds);
 
-/* Reboot the CPU */
-void cpu_reset(void);
-
-/* Board version information functions */
-uint32_t *board_get_info(void);
-void board_rw_contents_change(void);
-
 #endif /* !__ASSEMBLER__ */
 
 #endif /* __BOARD_H */
diff --git a/board/zinger/hardware.c b/board/zinger/hardware.c
index 1238d31a0d..54a92aaccd 100644
--- a/board/zinger/hardware.c
+++ b/board/zinger/hardware.c
@@ -298,16 +298,12 @@ int adc_disable_watchdog(void)
 #define STRT     (1<<6)
 #define CR_LOCK  (1<<7)
 
-int flash_write_rw(int offset, int size, const char *data)
+int flash_physical_write(int offset, int size, const char *data)
 {
-	uint16_t *address = (uint16_t *)
-		(CONFIG_FLASH_BASE + CONFIG_FW_RW_OFF + offset);
+	uint16_t *address = (uint16_t *)(CONFIG_FLASH_BASE + offset);
 	int res = EC_SUCCESS;
 	int i;
 
-	/* notify board of a RW flash contents change */
-	board_rw_contents_change();
-
 	if ((uint32_t)address > CONFIG_FLASH_BASE + CONFIG_FLASH_SIZE)
 		return EC_ERROR_INVAL;
 
@@ -353,14 +349,9 @@ exit_wr:
 	return res;
 }
 
-int flash_erase_rw(void)
+int flash_physical_erase(int offset, int size)
 {
 	int res = EC_SUCCESS;
-	int offset = CONFIG_FW_RW_OFF;
-	int size = CONFIG_FW_RW_SIZE;
-
-	/* notify board of a RW flash contents change */
-	board_rw_contents_change();
 
 	/* unlock CR if needed */
 	if (STM32_FLASH_CR & CR_LOCK) {
diff --git a/board/zinger/runtime.c b/board/zinger/runtime.c
index 0724c68c81..171c706bfa 100644
--- a/board/zinger/runtime.c
+++ b/board/zinger/runtime.c
@@ -205,6 +205,10 @@ void cpu_reset(void)
 		;
 }
 
+void system_reset(int flags)
+{
+	cpu_reset();
+}
 /**
  * Default exception handler, which reports a panic.
  *
diff --git a/board/zinger/usb_pd_policy.c b/board/zinger/usb_pd_policy.c
index e4cb5ea9f4..8442f689d6 100644
--- a/board/zinger/usb_pd_policy.c
+++ b/board/zinger/usb_pd_policy.c
@@ -14,7 +14,6 @@
 #include "timer.h"
 #include "util.h"
 #include "usb_pd.h"
-#include "version.h"
 
 /* ------------------------- Power supply control ------------------------ */
 
@@ -491,69 +490,33 @@ const struct svdm_response svdm_rsp = {
 static int pd_custom_vdm(int port, int cnt, uint32_t *payload,
 			 uint32_t **rpayload)
 {
-	static int flash_offset;
 	int cmd = PD_VDO_CMD(payload[0]);
-	int rsize = 1;
+	int rsize;
 
 	if (PD_VDO_VID(payload[0]) != USB_VID_GOOGLE || !gfu_mode)
 		return 0;
 
 	debug_printf("%T] VDM/%d [%d] %08x\n", cnt, cmd, payload[0]);
-
 	*rpayload = payload;
-	switch (cmd) {
-	case VDO_CMD_VERSION:
-		memcpy(payload + 1, &version_data.version, 24);
-		rsize = 7;
-		break;
-	case VDO_CMD_REBOOT:
-		/* ensure the power supply is in a safe state */
-		pd_power_supply_reset(0);
-		cpu_reset();
-		break;
-	case VDO_CMD_READ_INFO:
-		/* copy info into response */
-		memcpy(payload + 1, board_get_info(), 24);
-		rsize = 7;
-		break;
-	case VDO_CMD_FLASH_ERASE:
-		/* do not kill the code under our feet */
-		if (!is_ro_mode())
+
+	rsize = pd_custom_flash_vdm(port, cnt, payload);
+	if (!rsize) {
+		switch (cmd) {
+		case VDO_CMD_PING_ENABLE:
+			pd_ping_enable(0, payload[1]);
+			rsize = 1;
 			break;
-		flash_offset = 0;
-		flash_erase_rw();
-		break;
-	case VDO_CMD_FLASH_WRITE:
-		/* do not kill the code under our feet */
-		if (!is_ro_mode())
+		case VDO_CMD_CURRENT:
+			/* return last measured current */
+			payload[1] = ADC_TO_CURR_MA(vbus_amp);
+			rsize = 2;
 			break;
-		flash_write_rw(flash_offset, 4*(cnt - 1),
-			       (const char *)(payload+1));
-		flash_offset += 4*(cnt - 1);
-		break;
-	case VDO_CMD_ERASE_SIG:
-		/* this is not touching the code area */
-		{
-			uint32_t zero = 0;
-			int offset;
-			/* zeroes the area containing the RSA signature */
-			for (offset = CONFIG_FW_RW_SIZE - 256;
-			     offset < CONFIG_FW_RW_SIZE; offset += 4)
-				flash_write_rw(offset, 4, (const char *)&zero);
+		default:
+			/* Unknown : do not answer */
+			return 0;
 		}
-		break;
-	case VDO_CMD_PING_ENABLE:
-		pd_ping_enable(0, payload[1]);
-		break;
-	case VDO_CMD_CURRENT:
-		/* return last measured current */
-		payload[1] = ADC_TO_CURR_MA(vbus_amp);
-		rsize = 2;
-		break;
-	default:
-		/* Unknown : do not answer */
-		return 0;
 	}
+
 	debug_printf("%T] DONE\n");
 	/* respond (positively) to the request */
 	payload[0] |= VDO_SRC_RESPONDER;
diff --git a/chip/stm32/build.mk b/chip/stm32/build.mk
index 75f97fb7b2..c2577fe34a 100644
--- a/chip/stm32/build.mk
+++ b/chip/stm32/build.mk
@@ -26,7 +26,8 @@ endif
 # Select between 16-bit and 32-bit timer for clock source
 TIMER_TYPE=$(if $(CONFIG_STM_HWTIMER32),32,)
 
-chip-y=dma.o system.o
+chip-y=dma.o
+chip-$(CONFIG_COMMON_RUNTIME)+=system.o
 chip-y+=jtag-$(CHIP_FAMILY).o clock-$(CHIP_FAMILY).o
 chip-$(CONFIG_SPI)+=spi.o
 chip-$(CONFIG_SPI_MASTER_PORT)+=spi_master.o
@@ -40,9 +41,11 @@ chip-$(HAS_TASK_CONSOLE)+=uart.o
 chip-$(HAS_TASK_KEYSCAN)+=keyboard_raw.o
 chip-$(HAS_TASK_POWERLED)+=power_led.o
 chip-$(CONFIG_FLASH)+=flash-$(CHIP_FAMILY).o
+ifdef CONFIG_FLASH
 chip-$(CHIP_FAMILY_STM32F)+=flash-f.o
 chip-$(CHIP_FAMILY_STM32F0)+=flash-f.o
 chip-$(CHIP_FAMILY_STM32F3)+=flash-f.o
+endif
 chip-$(CONFIG_ADC)+=adc-$(CHIP_FAMILY).o
 chip-$(CONFIG_PWM)+=pwm.o
 chip-$(CONFIG_USB)+=usb.o usb-$(CHIP_FAMILY).o usb_endpoints.o
diff --git a/common/usb_pd_policy.c b/common/usb_pd_policy.c
index 5bcb58dd71..118a04fbed 100644
--- a/common/usb_pd_policy.c
+++ b/common/usb_pd_policy.c
@@ -6,10 +6,14 @@
 #include "atomic.h"
 #include "common.h"
 #include "console.h"
+#include "flash.h"
 #include "gpio.h"
 #include "hooks.h"
 #include "host_command.h"
 #include "registers.h"
+#include "rsa.h"
+#include "sha256.h"
+#include "system.h"
 #include "task.h"
 #include "timer.h"
 #include "util.h"
@@ -26,6 +30,8 @@
 #define CPRINTF(format, args...)
 #endif
 
+static int rw_flash_changed = 1;
+
 #ifdef CONFIG_USB_PD_ALT_MODE
 
 #ifdef CONFIG_USB_PD_ALT_MODE_DFP
@@ -475,3 +481,97 @@ DECLARE_HOST_COMMAND(EC_CMD_USB_PD_DISCOVERY,
 		     hc_remote_pd_discovery,
 		     EC_VER_MASK(0));
 #endif
+
+#define FW_RW_END (CONFIG_FW_RW_OFF + CONFIG_FW_RW_SIZE)
+
+uint8_t *flash_hash_rw(void)
+{
+	static struct sha256_ctx ctx;
+
+	/* re-calculate RW hash when changed as its time consuming */
+	if (rw_flash_changed) {
+		rw_flash_changed = 0;
+		SHA256_init(&ctx);
+		SHA256_update(&ctx, (void *)CONFIG_FLASH_BASE +
+			      CONFIG_FW_RW_OFF,
+			      CONFIG_FW_RW_SIZE - RSANUMBYTES);
+		return SHA256_final(&ctx);
+	} else {
+		return ctx.buf;
+	}
+}
+
+void pd_get_info(uint32_t *info_data)
+{
+	void *rw_hash = flash_hash_rw();
+
+	/* copy first 20 bytes of RW hash */
+	memcpy(info_data, rw_hash, 5 * sizeof(uint32_t));
+	/* copy other info into data msg */
+#if defined(CONFIG_USB_PD_HW_DEV_ID_BOARD_MAJOR) && \
+	defined(CONFIG_USB_PD_HW_DEV_ID_BOARD_MINOR)
+	info_data[5] = VDO_INFO(CONFIG_USB_PD_HW_DEV_ID_BOARD_MAJOR,
+				CONFIG_USB_PD_HW_DEV_ID_BOARD_MINOR,
+				ver_get_numcommits(),
+				(system_get_image_copy() != SYSTEM_IMAGE_RO));
+#else
+	info_data[5] = 0;
+#endif
+}
+
+int pd_custom_flash_vdm(int port, int cnt, uint32_t *payload)
+{
+	static int flash_offset;
+	int rsize = 1; /* default is just VDM header returned */
+
+	switch (PD_VDO_CMD(payload[0])) {
+	case VDO_CMD_VERSION:
+		memcpy(payload + 1, &version_data.version, 24);
+		rsize = 7;
+		break;
+	case VDO_CMD_REBOOT:
+		/* ensure the power supply is in a safe state */
+		pd_power_supply_reset(0);
+		system_reset(0);
+		break;
+	case VDO_CMD_READ_INFO:
+		/* copy info into response */
+		pd_get_info(payload + 1);
+		rsize = 7;
+		break;
+	case VDO_CMD_FLASH_ERASE:
+		/* do not kill the code under our feet */
+		if (system_get_image_copy() != SYSTEM_IMAGE_RO)
+			break;
+		flash_offset = CONFIG_FW_RW_OFF;
+		flash_physical_erase(CONFIG_FW_RW_OFF, CONFIG_FW_RW_SIZE);
+		rw_flash_changed = 1;
+		break;
+	case VDO_CMD_FLASH_WRITE:
+		/* do not kill the code under our feet */
+		if ((system_get_image_copy() != SYSTEM_IMAGE_RO) ||
+		    (flash_offset < CONFIG_FW_RW_OFF))
+			break;
+		flash_physical_write(flash_offset, 4*(cnt - 1),
+				     (const char *)(payload+1));
+		flash_offset += 4*(cnt - 1);
+		rw_flash_changed = 1;
+		break;
+	case VDO_CMD_ERASE_SIG:
+		/* this is not touching the code area */
+		{
+			uint32_t zero = 0;
+			int offset;
+			/* zeroes the area containing the RSA signature */
+			for (offset = FW_RW_END - RSANUMBYTES;
+			     offset < FW_RW_END; offset += 4)
+				flash_physical_write(offset, 4,
+						     (const char *)&zero);
+		}
+		break;
+	default:
+		/* Unknown : do not answer */
+		return 0;
+	}
+	return rsize;
+}
diff --git a/common/usb_pd_protocol.c b/common/usb_pd_protocol.c
index d24a8ef524..131a441913 100644
--- a/common/usb_pd_protocol.c
+++ b/common/usb_pd_protocol.c
@@ -15,8 +15,6 @@
 #include "hooks.h"
 #include "host_command.h"
 #include "registers.h"
-#include "rsa.h"
-#include "sha256.h"
 #include "system.h"
 #include "task.h"
 #include "timer.h"
@@ -1329,35 +1327,6 @@ void pd_dev_store_rw_hash(int port, uint16_t dev_id, uint32_t *rw_hash)
 		pd_dev_dump_info(dev_id, (uint8_t *)rw_hash);
 }
 
-uint8_t *flash_hash_rw(void)
-{
-	static struct sha256_ctx ctx;
-	SHA256_init(&ctx);
-	SHA256_update(&ctx, (void *)CONFIG_FLASH_BASE + CONFIG_FW_RW_OFF,
-		    CONFIG_FW_RW_SIZE - RSANUMBYTES);
-	return SHA256_final(&ctx);
-}
-
-void pd_get_info(uint32_t *info_data)
-{
-	void *hash;
-
-	/* calculate RW hash */
-	hash = flash_hash_rw();
-	/* copy first 20 bytes of RW hash */
-	memcpy(info_data, hash, 5 * sizeof(uint32_t));
-	/* copy other info into data msg */
-#if defined(CONFIG_USB_PD_HW_DEV_ID_BOARD_MAJOR) && \
-	defined(CONFIG_USB_PD_HW_DEV_ID_BOARD_MINOR)
-	info_data[5] = VDO_INFO(CONFIG_USB_PD_HW_DEV_ID_BOARD_MAJOR,
-				CONFIG_USB_PD_HW_DEV_ID_BOARD_MINOR,
-				ver_get_numcommits(),
-				(system_get_image_copy() != SYSTEM_IMAGE_RO));
-#else
-	info_data[5] = 0;
-#endif
-}
-
 #ifdef CONFIG_USB_PD_DUAL_ROLE
 void pd_set_dual_role(enum pd_dual_role_states state)
 {
diff --git a/include/usb_pd.h b/include/usb_pd.h
index 9b6ddaac83..7418988236 100644
--- a/include/usb_pd.h
+++ b/include/usb_pd.h
@@ -821,6 +821,16 @@ int pd_vdm(int port, int cnt, uint32_t *payload, uint32_t **rpayload);
 int pd_svdm(int port, int cnt, uint32_t *payload, uint32_t **rpayload);
 
 /**
+ * Handle Custom VDMs for flashing.
+ *
+ * @param port     USB-C port number
+ * @param cnt      number of data objects in the payload.
+ * @param payload  payload data.
+ * @return if >0, number of VDOs to send back.
+ */
+int pd_custom_flash_vdm(int port, int cnt, uint32_t *payload);
+
+/**
  * Exit alternate mode
  *
  * @param port     USB-C port number
@@ -1165,4 +1175,5 @@ void pd_soft_reset(void);
  * @param port USB-C port number
  */
 void pd_set_new_power_request(int port);
+
 #endif  /* __USB_PD_H */