Revert "Add OTP support"

This reverts commit 1b25735b732e7766aceb3f060e4ca205aba6d358.

BUG=b:200823466
TEST=make buildall -j

Change-Id: I2e29902d7026c63f23871af0141a3ee7d319852d
Signed-off-by: Mary Ruthven <mruthven@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/3273456
Reviewed-by: Vadim Sukhomlinov <sukhomlinov@chromium.org>

8 files changed, 32 insertions, 101 deletions

diff --git a/chip/g/usb.c b/chip/g/usb.c
index 377eb8a470..d12566e701 100644
--- a/chip/g/usb.c
+++ b/chip/g/usb.c
@@ -1531,7 +1531,7 @@ static int usb_set_serial(const char *serialno)
 		return EC_ERROR_INVAL;
 
 	/* Convert into unicode usb string desc. */
-	for (i = 0; i < CONFIG_SERIALNO_LEN; i++) {
+	for (i = 0; i < USB_STRING_LEN; i++) {
 		sd->_data[i] = serialno[i];
 		if (serialno[i] == 0)
 			break;
diff --git a/common/flash.c b/common/flash.c
index f2ab3dcd27..ae08fdbd5f 100644
--- a/common/flash.c
+++ b/common/flash.c
@@ -11,7 +11,6 @@
 #include "gpio.h"
 #include "hooks.h"
 #include "host_command.h"
-#include "otp.h"
 #include "rwsig.h"
 #include "shared_mem.h"
 #include "system.h"
@@ -41,6 +40,7 @@
 /* NOTE: It's not expected that RO and RW will support
  * differing PSTATE versions. */
 #define PERSIST_STATE_VERSION 3  /* Expected persist_state.version */
+#define SERIALNO_MAX 28
 
 /* Flags for persist_state.flags */
 /* Protect persist state and RO firmware at boot */
@@ -53,11 +53,7 @@ struct persist_state {
 	uint8_t flags;              /* Lock flags (PERSIST_FLAG_*) */
 	uint8_t valid_fields;       /* Flags for valid data. */
 	uint8_t reserved;           /* Reserved; set 0 */
-#ifdef CONFIG_SERIALNO_LEN
-	uint8_t serialno[CONFIG_SERIALNO_LEN]; /* Serial number. */
-#else
-	uint8_t padding[4 % CONFIG_FLASH_WRITE_SIZE];
-#endif
+	uint8_t serialno[SERIALNO_MAX]; /* Serial number. */
 };
 /* written with flash_physical_write, need to respect alignment constraints */
 #ifndef CHIP_FAMILY_STM32L /* STM32L1xx is somewhat lying to us */
@@ -226,11 +222,10 @@ static uint32_t flash_read_pstate(void)
 	}
 }
 
-#ifdef CONFIG_SERIALNO_LEN
 /**
  * Read and return persistent serial number.
  */
-const char *flash_read_pstate_serial(void)
+static const char *flash_read_pstate_serial(void)
 {
 	const struct persist_state *pstate =
 		(const struct persist_state *)
@@ -241,9 +236,8 @@ const char *flash_read_pstate_serial(void)
 		return (const char *)(pstate->serialno);
 	}
 
-	return NULL;
+	return 0;
 }
-#endif
 
 /**
  * Write persistent state after erasing.
@@ -324,14 +318,13 @@ static int flash_write_pstate(uint32_t flags)
 	return flash_write_pstate_data(&newpstate);
 }
 
-#ifdef CONFIG_SERIALNO_LEN
 /**
  * Write persistent serial number to pstate, erasing if necessary.
  *
  * @param serialno		New iascii serial number to set in pstate.
  * @return EC_SUCCESS, or nonzero if error.
  */
-int flash_write_pstate_serial(const char *serialno)
+static int flash_write_pstate_serial(const char *serialno)
 {
 	int i;
 	struct persist_state newpstate;
@@ -348,18 +341,17 @@ int flash_write_pstate_serial(const char *serialno)
 	validate_pstate_struct(&newpstate);
 
 	/* Copy in serialno. */
-	for (i = 0; i < CONFIG_SERIALNO_LEN - 1; i++) {
+	for (i = 0; i < SERIALNO_MAX - 1; i++) {
 		newpstate.serialno[i] = serialno[i];
 		if (serialno[i] == 0)
 			break;
 	}
-	for (; i < CONFIG_SERIALNO_LEN; i++)
+	for (; i < SERIALNO_MAX; i++)
 		newpstate.serialno[i] = 0;
 	newpstate.valid_fields |= PSTATE_VALID_SERIALNO;
 
 	return flash_write_pstate_data(&newpstate);
 }
-#endif
 
 
 
@@ -547,6 +539,24 @@ int flash_erase(int offset, int size)
 	return flash_physical_erase(offset, size);
 }
 
+const char *flash_read_serial(void)
+{
+#if defined(CONFIG_FLASH_PSTATE) && defined(CONFIG_FLASH_PSTATE_BANK)
+	return flash_read_pstate_serial();
+#else
+	return 0;
+#endif
+}
+
+int flash_write_serial(const char *serialno)
+{
+#if defined(CONFIG_FLASH_PSTATE) && defined(CONFIG_FLASH_PSTATE_BANK)
+	return flash_write_pstate_serial(serialno);
+#else
+	return EC_ERROR_UNIMPLEMENTED;
+#endif
+}
+
 int flash_protect_at_boot(uint32_t new_flags)
 {
 #ifdef CONFIG_FLASH_PSTATE
diff --git a/common/system.c b/common/system.c
index a636813e2b..0aba47d1fb 100644
--- a/common/system.c
+++ b/common/system.c
@@ -15,7 +15,6 @@
 #include "host_command.h"
 #include "i2c.h"
 #include "lpc.h"
-#include "otp.h"
 #include "rwsig.h"
 #include "spi_flash.h"
 #ifdef CONFIG_MPU
@@ -1292,34 +1291,3 @@ int system_can_boot_ap(void)
 	/* For fixed AC system */
 	return 1;
 }
-
-#ifdef CONFIG_SERIALNO_LEN
-/* By default, read serial number from flash, can be overridden. */
-#if defined(CONFIG_FLASH_PSTATE) && defined(CONFIG_FLASH_PSTATE_BANK)
-__attribute__((weak))
-const char *board_read_serial(void)
-{
-	return flash_read_pstate_serial();
-}
-#elif defined(CONFIG_OTP)
-__attribute__((weak))
-const char *board_read_serial(void)
-{
-	return otp_read_serial();
-}
-#endif
-
-#if defined(CONFIG_FLASH_PSTATE) && defined(CONFIG_FLASH_PSTATE_BANK)
-__attribute__((weak))
-int board_write_serial(const char *serialno)
-{
-	return flash_write_pstate_serial(serialno);
-}
-#elif defined(CONFIG_OTP)
-__attribute__((weak))
-int board_write_serial(const char *serialno)
-{
-	return otp_write_serial(serialno);
-}
-#endif
-#endif  /* CONFIG_SERIALNO_LEN */
diff --git a/include/config.h b/include/config.h
index 98331cb453..128c0dc88b 100644
--- a/include/config.h
+++ b/include/config.h
@@ -2658,9 +2658,6 @@
 /* Support one-wire interface */
 #undef CONFIG_ONEWIRE
 
-/* Support One Time Protection structure */
-#undef CONFIG_OTP
-
 /* Support PECI interface to x86 processor */
 #undef CONFIG_PECI
 
@@ -2924,9 +2921,6 @@
 #undef CONFIG_RW_SIG_ADDR
 #undef CONFIG_RW_SIG_SIZE
 
-/* Size of the serial number if needed */
-#undef CONFIG_SERIALNO_LEN
-
 /****************************************************************************/
 /* Shared objects library. */
 
@@ -4603,10 +4597,6 @@
 #error "CONFIG_AUX_TIMER_PERIOD_MS must be at least 2x HOOK_TICK_INTERVAL_MS"
 #endif
 
-#ifdef CONFIG_USB_SERIALNO
-#define CONFIG_SERIALNO_LEN 28
-#endif
-
 #ifndef CONFIG_EC_MAX_SENSOR_FREQ_MILLIHZ
 #define CONFIG_EC_MAX_SENSOR_FREQ_MILLIHZ \
 	CONFIG_EC_MAX_SENSOR_FREQ_DEFAULT_MILLIHZ
diff --git a/include/flash.h b/include/flash.h
index e2c572d38f..0566c5914a 100644
--- a/include/flash.h
+++ b/include/flash.h
@@ -320,18 +320,17 @@ int flash_set_protect(uint32_t mask, uint32_t flags);
  * Get the serial number from flash.
  *
  * @return char * ascii serial number string.
- *     NULL if error.
  */
-const char *flash_read_pstate_serial(void);
+const char *flash_read_serial(void);
 
 /**
  * Set the serial number in flash.
  *
- * @param serialno	ascii serial number string.
+ * @param serialno	ascii serial number string < 30 char.
  *
  * @return success status.
  */
-int flash_write_pstate_serial(const char *serialno);
+int flash_write_serial(const char *serialno);
 
 /**
  * Lock or unlock HW necessary for mapped storage read.
diff --git a/include/otp.h b/include/otp.h
deleted file mode 100644
index 7851411202..0000000000
--- a/include/otp.h
+++ /dev/null
@@ -1,32 +0,0 @@
-/* Copyright 2017 The Chromium OS Authors. All rights reserved.
- * Use of this source code is governed by a BSD-style license that can be
- * found in the LICENSE file.
- */
-
-/* OTP memory module for Chrome EC */
-
-#ifndef __CROS_EC_OTP_H
-#define __CROS_EC_OTP_H
-
-/*
- * OTP: One Time Programable memory is used for storing persistent data.
- */
-
-/**
- * Set the serial number in OTP memory.
- *
- * @param serialno	ascii serial number string.
- *
- * @return success status.
- */
-int otp_write_serial(const char *serialno);
-
-/**
- * Get the serial number from flash.
- *
- * @return char * ascii serial number string.
- *     NULL if error.
- */
-const char *otp_read_serial(void);
-
-#endif  /* __CROS_EC_OTP_H */
diff --git a/include/system.h b/include/system.h
index 98b580e19a..bf9e19130a 100644
--- a/include/system.h
+++ b/include/system.h
@@ -270,15 +270,10 @@ int system_get_chip_unique_id(uint8_t **id);
 
 /**
  * Optional board-level callback functions to read a unique serial number per
- * chip. Default implementation reads from flash/otp (flash/otp_read_serial).
+ * chip. Default implementation reads from flash (flash_read_serial).
  */
 const char *board_read_serial(void) __attribute__((weak));
 
-/**
- * Optional board-level callback functions to write a unique serial number per
- * chip. Default implementation reads from flash/otp (flash/otp_write_serial).
- */
-int board_write_serial(const char *serial) __attribute__((weak));
 /*
  * Common bbram entries. Chips don't necessarily need to implement
  * all of these, error will be returned from system_get/set_bbram if
diff --git a/include/usb_descriptor.h b/include/usb_descriptor.h
index 153c648085..06dfdbc0ed 100644
--- a/include/usb_descriptor.h
+++ b/include/usb_descriptor.h
@@ -312,10 +312,11 @@ struct usb_setup_packet {
 
 #ifdef CONFIG_USB_SERIALNO
 /* String Descriptor for USB, for editable strings. */
+#define USB_STRING_LEN 28
 struct usb_string_desc {
 	uint8_t _len;
 	uint8_t _type;
-	wchar_t _data[CONFIG_SERIALNO_LEN];
+	wchar_t _data[USB_STRING_LEN];
 };
 #define USB_WR_STRING_DESC(str) \
 	(&(struct usb_string_desc) { \