Hi Paul,
On 4. 08. 25 19:30, Paul Geurts wrote:
>> The family of PCA9450 PMICs have the ability to perform system resets.
>> Restarting via PMIC is preferred method of restarting the system as all
>> the peripherals are brought to a know state after a power-cycle. The
>> PCA9450 features a cold restart procedure which is initiated by an I2C
>> command 0x14 to the SW_RST register.
>>
>> Support in Linux for restarting via PCA9450 PMIC has been added by
>> Linux commit 6157e62b07d9 ("regulator: pca9450: Add restart handler").
>>
>> Now add support for it also in the U-Boot via sysreset framework.
>>
>> Signed-off-by: Primoz Fiser <primoz.fi...@norik.com>
>> ---
>> drivers/power/pmic/pca9450.c | 42 ++++++++++++++++++++++++++++++++++++
>> include/power/pca9450.h | 2 ++
>> 2 files changed, 44 insertions(+)
>>
>> diff --git a/drivers/power/pmic/pca9450.c b/drivers/power/pmic/pca9450.c
>> index 9d875f8bdbe8..abc39d0a1946 100644
>> --- a/drivers/power/pmic/pca9450.c
>> +++ b/drivers/power/pmic/pca9450.c
>> @@ -7,15 +7,18 @@
>> #include <errno.h>
>> #include <dm.h>
>> #include <dm/device_compat.h>
>> +#include <dm/lists.h>
>> #include <i2c.h>
>> #include <linux/err.h>
>> #include <log.h>
>> #include <asm/global_data.h>
>> #include <asm-generic/gpio.h>
>> +#include <linux/delay.h>
>> #include <linux/printk.h>
>> #include <power/pmic.h>
>> #include <power/regulator.h>
>> #include <power/pca9450.h>
>> +#include <sysreset.h>
>>
>> DECLARE_GLOBAL_DATA_PTR;
>>
>> @@ -101,6 +104,14 @@ static int pca9450_probe(struct udevice *dev)
>> }
>> }
>>
>> + if (CONFIG_IS_ENABLED(SYSRESET)) {
>> + ret = device_bind_driver_to_node(dev, "pca9450_sysreset",
>> + "pca9450_sysreset",
>> + dev_ofnode(dev), NULL);
>> + if (ret)
>> + return ret;
>> + }
>> +
>> if (ofnode_read_bool(dev_ofnode(dev), "nxp,wdog_b-warm-reset"))
>> reset_ctrl = PCA9450_PMIC_RESET_WDOG_B_CFG_WARM;
>> else
>> @@ -134,3 +145,34 @@ U_BOOT_DRIVER(pmic_pca9450) = {
>> .ops = &pca9450_ops,
>> .priv_auto = sizeof(struct pca9450_priv),
>> };
>> +
>> +#ifdef CONFIG_SYSRESET
>> +static int pca9450_sysreset_request(struct udevice *dev, enum sysreset_t
>> type)
>> +{
>> + u8 cmd = PCA9450_SW_RST_COLD_RST;
>> +
>> + if (type != SYSRESET_COLD)
>
> The PCA9450 calls it "cold reset", but it is technically SYSRESET_POWER.
> There is no option for it in the sysreset do_reset, but maybe there should be.
Yeah, the default is SYSRESET_COLD.
Additionally, there is only support for warm rst type (SYSRESET_WARM) in
do_reset for now.
I decided not to implement it to keep it as simple as possible and in
sync with your Linux support.
>
>> + return -EPROTONOSUPPORT;
>> +
>> + if (pmic_write(dev->parent, PCA9450_SW_RST, &cmd, 1)) {
>> + dev_err(dev, "reset command failed\n");
>> + } else {
>> + /* tRESTART is 250ms, delay 300ms just to be sure */
>> + mdelay(300);
>> + /* Should not get here, warn if we do */
>> + dev_warn(dev, "didn't respond to reset command\n");
>> + }
>> +
>> + return -EINPROGRESS;
>> +}
>> +
>> +static struct sysreset_ops pca9450_sysreset_ops = {
>> + .request = pca9450_sysreset_request,
>
> When using the PCA9450 to perform a cold reset, the CPU boot status shall
> _always_ be POR, as that is what the CPU detects. This means the boot status
> should also come from the PCA9450 when enabling CONFIG_SYSRESET option.
>
> I think implementing pca9450_sysreset_ops.get_status() to read the
> PWRON_STAT register should do the trick, but I am not that familiar with the
> sysreset in U-Boot.
You read my mind :)
I have support for get_status() already prepared but I am waiting for
this patch to get applied first.
Your Reviewed-by tag would help here if possible?
>
>> +};
>> +
>> +U_BOOT_DRIVER(pca9450_sysreset) = {
>> + .name = "pca9450_sysreset",
>> + .id = UCLASS_SYSRESET,
>> + .ops = &pca9450_sysreset_ops,
>> +};
>> +#endif /* CONFIG_SYSRESET */
>> diff --git a/include/power/pca9450.h b/include/power/pca9450.h
>> index e5ab09fb8c83..9119ef793b1f 100644
>> --- a/include/power/pca9450.h
>> +++ b/include/power/pca9450.h
>> @@ -75,4 +75,6 @@ enum {
>> #define PCA9450_PMIC_RESET_WDOG_B_CFG_WARM 0x40
>> #define PCA9450_PMIC_RESET_WDOG_B_CFG_COLD_LDO12 0x80
>>
>> +#define PCA9450_SW_RST_COLD_RST 0x14
>> +
>> #endif
>>
>
> Thanks for porting it to U-Boot :-)
You're welcome.
Thanks for adding support in Linux.
BR,
Primoz
>
> br,
> Paul
--
Primoz Fiser
phone: +386-41-390-545
email: primoz.fi...@norik.com
--
Norik systems d.o.o.
Your embedded software partner
Slovenia, EU
phone: +386-41-540-545
email: i...@norik.com
