am335x, guardian: software update available status is stored in AM3352 RTC scracth register

RTC second scratch register[32-bit]:
  -zero byte hold boot count value
  -first byte hold update available state
  -second byte hold version
  -third byte hold magic number

Signed-off-by: Gireesh Hiremath <Gireesh.Hiremath@in.bosch.com>

Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Link: https://lore.kernel.org/r/20210611161350.2141-17-Gireesh.Hiremath@in.bosch.com
Gbp-Pq: Topic apertis/guardian
Gbp-Pq: Name am335x-guardian-software-update-available-status-is-store.patch
diff --git a/drivers/bootcount/Kconfig b/drivers/bootcount/Kconfig
index b5ccea0..0de2b7b 100644
--- a/drivers/bootcount/Kconfig
+++ b/drivers/bootcount/Kconfig
@@ -42,6 +42,25 @@
 	  This requires the RTC clocks, etc, to be enabled prior to use and
 	  not all boards with this IP block on it will have the RTC in use.
 
+config BOOTCOUNT_AM33XX_NVMEM
+	bool "Boot counter in AM33XX RTC IP block with upgrade_available flag"
+	depends on AM33XX
+        select SPL_AM33XX_ENABLE_RTC32K_OSC if AM33XX
+	help
+	  Add support for maintaining bootcount,upgrade_available,
+	  version and BOOTMAGIC in a AM33xx RTC IP block
+	  scratch register2.
+
+	  A bootcount driver for the RTC IP block found on many TI platforms.
+	  This requires the RTC clocks, etc, to be enabled prior to use and
+	  not all boards with this IP block on it will have the RTC in use.
+
+	  If there is upgrade in software then "upgrade_available" is 1,
+	  "bootcount" is incremented otherwise "upgrade_available" and
+	  "bootcount" is  always 0. So the Userspace Application must set
+	  the "upgrade_available" and "bootcount" variable to 0, if a boot
+	  was successfully.
+
 config BOOTCOUNT_ENV
 	bool "Boot counter in environment"
 	help
@@ -177,16 +196,25 @@
 
 config SYS_BOOTCOUNT_ADDR
 	hex "RAM address used for reading and writing the boot counter"
-	default 0x44E3E000 if BOOTCOUNT_AM33XX
+	default 0x44E3E000 if BOOTCOUNT_AM33XX || BOOTCOUNT_AM33XX_NVMEM
 	default 0xE0115FF8 if ARCH_LS1043A || ARCH_LS1021A
 	depends on BOOTCOUNT_AM33XX || BOOTCOUNT_GENERIC || BOOTCOUNT_EXT || \
-		   BOOTCOUNT_I2C
+		   BOOTCOUNT_I2C || BOOTCOUNT_AM33XX_NVMEM
 	help
 	  Set the address used for reading and writing the boot counter.
 
 config SYS_BOOTCOUNT_MAGIC
 	hex "Magic value for the boot counter"
-	default 0xB001C041
+	default 0xB001C041 if BOOTCOUNT_GENERIC || BOOTCOUNT_EXT || \
+			      BOOTCOUNT_AM33XX || BOOTCOUNT_ENV || \
+			      BOOTCOUNT_RAM || BOOTCOUNT_I2C || \
+			      BOOTCOUNT_AT91 || DM_BOOTCOUNT
+	default 0xB0 if BOOTCOUNT_AM33XX_NVMEM
+	depends on BOOTCOUNT_GENERIC || BOOTCOUNT_EXT || \
+		   BOOTCOUNT_AM33XX || BOOTCOUNT_ENV || \
+		   BOOTCOUNT_RAM || BOOTCOUNT_I2C || \
+		   BOOTCOUNT_AT91 || DM_BOOTCOUNT || \
+		   BOOTCOUNT_AM33XX_NVMEM
 	help
 	  Set the magic value used for the boot counter.