According to i.MX7ULP Reference Manual we should wait for WDOG unlock
and reconfiguration to complete.
Section "59.5.3 Configure Watchdog" provides the following example:
DisableInterrupts; //disable global interrupt
WDOG_CNT = 0xD928C520; //unlock watchdog
while(WDOG_CS[ULK]==0); //wait until registers are unlocked
WDOG_TOVAL = 256; //set timeout value
WDOG_CS = WDOG_CS_EN(1) | WDOG_CS_CLK(1) | WDOG_CS_INT(1) |
WDOG_CS_WIN(0) | WDOG_CS_UPDATE(1);
while(WDOG_CS[RCS]==0); //wait until new configuration takes effect
EnableInterrupts; //enable global interrupt
Update U-Boot WDOG driver to align with i.MX7ULP reference manual.
Use 32 bits accessing to CS register. According to RM, the bits in
this register only can write once after unlock. So using 8 bits access
will cause problem.
Reviewed-by: Ye Li <ye.li@nxp.com>
Signed-off-by: Breno Lima <breno.lima@nxp.com>
Signed-off-by: Peng Fan <peng.fan@nxp.com>
According to i.MX7ULP Reference Manual the second word write for both
UNLOCK and REFRESH operations must occur in maximum 16 bus clock.
The current code is using writel() function which has a DMB barrier to
order the memory access. The DMB between two words write may introduce
some delay in certain circumstance, causing a WDOG timeout due to 16 bus
clock window requirement.
Replace writel() function by __raw_writel() to achieve a faster memory
access and avoid such issue.
Reviewed-by: Ye Li <ye.li@nxp.com>
Signed-off-by: Breno Lima <breno.lima@nxp.com>
Historically, the reset_cpu() function had an `addr` parameter which was
meant to pass in an address of the reset vector location, where the CPU
should reset to. This feature is no longer used anywhere in U-Boot as
all reset_cpu() implementations now ignore the passed value. Generic
code has been added which always calls reset_cpu() with `0` which means
this feature can no longer be used easily anyway.
Over time, many implementations seem to have "misunderstood" the
existence of this parameter as a way to customize/parameterize the reset
(e.g. COLD vs WARM resets). As this is not properly supported, the
code will almost always not do what it is intended to (because all
call-sites just call reset_cpu() with 0).
To avoid confusion and to clean up the codebase from unused left-overs
of the past, remove the `addr` parameter entirely. Code which intends
to support different kinds of resets should be rewritten as a sysreset
driver instead.
This transformation was done with the following coccinelle patch:
@@
expression argvalue;
@@
- reset_cpu(argvalue)
+ reset_cpu()
@@
identifier argname;
type argtype;
@@
- reset_cpu(argtype argname)
+ reset_cpu(void)
{ ... }
Signed-off-by: Harald Seiler <hws@denx.de>
Reviewed-by: Simon Glass <sjg@chromium.org>
When U-Boot started using SPDX tags we were among the early adopters and
there weren't a lot of other examples to borrow from. So we picked the
area of the file that usually had a full license text and replaced it
with an appropriate SPDX-License-Identifier: entry. Since then, the
Linux Kernel has adopted SPDX tags and they place it as the very first
line in a file (except where shebangs are used, then it's second line)
and with slightly different comment styles than us.
In part due to community overlap, in part due to better tag visibility
and in part for other minor reasons, switch over to that style.
This commit changes all instances where we have a single declared
license in the tag as both the before and after are identical in tag
contents. There's also a few places where I found we did not have a tag
and have introduced one.
Signed-off-by: Tom Rini <trini@konsulko.com>
We have a large number of places where while we historically referenced
gd in the code we no longer do, as well as cases where the code added
that line "just in case" during development and never dropped it.
Signed-off-by: Tom Rini <trini@konsulko.com>
This driver implements the HW WATCHDOG functions. Which needs
to set CONFIG_HW_WATCHDOG to use them. This is disabled by default for
mx7ulp.
Use watchdog for reset cpu. Implement this in the driver.
Need to define CONFIG_ULP_WATCHDOG to build it.
Signed-off-by: Peng Fan <peng.fan@nxp.com>
Signed-off-by: Ye Li <ye.li@nxp.com>
Cc: Stefano Babic <sbabic@denx.de>
