u-boot/drivers/bootcount/bootcount_nvmem.c
Gireesh Hiremath caf9478624 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
2021-07-15 17:56:03 +05:30

57 lines
1.4 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* (C) Copyright 2011
* Heiko Schocher, DENX Software Engineering, hs@denx.de.
* (C) Copyright 2018 Robert Bosch Power Tools GmbH.
*
* 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.
*/
#include <bootcount.h>
#include <asm/davinci_rtc.h>
#define BC_VERSION 2
void bootcount_store(ulong bootcount)
{
u8 upgrade_available = 0;
ulong val = 0;
struct davinci_rtc *reg =
(struct davinci_rtc *)CONFIG_SYS_BOOTCOUNT_ADDR;
val = raw_bootcount_load(&reg->scratch2);
upgrade_available = (val >> 8) & 0x000000ff;
/* Only update bootcount during upgrade process */
if (!upgrade_available)
bootcount = 0;
val = (bootcount & 0x000000ff) |
(upgrade_available << 8) |
(BC_VERSION << 16) |
(CONFIG_SYS_BOOTCOUNT_MAGIC << 24);
/*
* write RTC kick registers to enable write
* for RTC Scratch registers. Scratch register 2 is
* used for bootcount value.
*/
writel(RTC_KICK0R_WE, &reg->kick0r);
writel(RTC_KICK1R_WE, &reg->kick1r);
raw_bootcount_store(&reg->scratch2, val);
}
ulong bootcount_load(void)
{
unsigned long val = 0;
struct davinci_rtc *reg =
(struct davinci_rtc *)CONFIG_SYS_BOOTCOUNT_ADDR;
val = raw_bootcount_load(&reg->scratch2);
if ((val >> 24) != CONFIG_SYS_BOOTCOUNT_MAGIC)
return 0;
else
return val & 0x000000ff;
}