Hi, On Wed, Mar 04, 2026 at 11:33:02PM +0530, Shivendra Pratap wrote: > Current reboot-mode supports a single 32-bit argument for any > supported mode. Some reboot-mode based drivers may require > passing two independent 32-bit arguments during a reboot > sequence, for uses-cases, where a mode requires an additional > argument. Such drivers may not be able to use the reboot-mode > driver. For example, ARM PSCI vendor-specific resets, need two > arguments for its operation – reset_type and cookie, to complete > the reset operation. If a driver wants to implement this > firmware-based reset, it cannot use reboot-mode framework. > > Introduce 64-bit magic values in reboot-mode driver to > accommodate up-to two 32-bit arguments in below format. > | Higher 32 bit | Lower 32 bit | > | arg2 | arg1 | > > Update current reboot-mode drivers for 64-bit magic. > > Signed-off-by: Shivendra Pratap > --- Reviewed-by: Sebastian Reichel -- Sebastian > drivers/power/reset/nvmem-reboot-mode.c | 8 ++++---- > drivers/power/reset/qcom-pon.c | 6 +++--- > drivers/power/reset/reboot-mode.c | 16 +++++++++------- > drivers/power/reset/syscon-reboot-mode.c | 6 +++--- > include/linux/reboot-mode.h | 15 ++++++++++++++- > 5 files changed, 33 insertions(+), 18 deletions(-) > > diff --git a/drivers/power/reset/nvmem-reboot-mode.c b/drivers/power/reset/nvmem-reboot-mode.c > index d260715fccf67f9f072bb56c5defbf885750650e..bd05d660490c686b43134f82f1eadd7665403d20 100644 > --- a/drivers/power/reset/nvmem-reboot-mode.c > +++ b/drivers/power/reset/nvmem-reboot-mode.c > @@ -17,10 +17,10 @@ struct nvmem_reboot_mode { > struct nvmem_cell *cell; > }; > > -static int nvmem_reboot_mode_write(struct reboot_mode_driver *reboot, > - unsigned int magic) > +static int nvmem_reboot_mode_write(struct reboot_mode_driver *reboot, u64 magic) > { > struct nvmem_reboot_mode *nvmem_rbm; > + u32 magic_arg1 = REBOOT_MODE_ARG1(magic); > size_t buf_len; > void *buf; > int ret; > @@ -32,10 +32,10 @@ static int nvmem_reboot_mode_write(struct reboot_mode_driver *reboot, > return PTR_ERR(buf); > kfree(buf); > > - if (buf_len > sizeof(magic)) > + if (buf_len > sizeof(magic_arg1)) > return -EINVAL; > > - ret = nvmem_cell_write(nvmem_rbm->cell, &magic, buf_len); > + ret = nvmem_cell_write(nvmem_rbm->cell, &magic_arg1, buf_len); > if (ret < 0) > dev_err(reboot->dev, "update reboot mode bits failed\n"); > > diff --git a/drivers/power/reset/qcom-pon.c b/drivers/power/reset/qcom-pon.c > index 7e108982a582e8243c5c806bd4a793646b87189f..57b36e6186f80aff947fd7f5aae5ce280c65dc6b 100644 > --- a/drivers/power/reset/qcom-pon.c > +++ b/drivers/power/reset/qcom-pon.c > @@ -27,17 +27,17 @@ struct qcom_pon { > long reason_shift; > }; > > -static int qcom_pon_reboot_mode_write(struct reboot_mode_driver *reboot, > - unsigned int magic) > +static int qcom_pon_reboot_mode_write(struct reboot_mode_driver *reboot, u64 magic) > { > struct qcom_pon *pon = container_of > (reboot, struct qcom_pon, reboot_mode); > + u32 magic_arg1 = REBOOT_MODE_ARG1(magic); > int ret; > > ret = regmap_update_bits(pon->regmap, > pon->baseaddr + PON_SOFT_RB_SPARE, > GENMASK(7, pon->reason_shift), > - magic << pon->reason_shift); > + magic_arg1 << pon->reason_shift); > if (ret < 0) > dev_err(pon->dev, "update reboot mode bits failed\n"); > > diff --git a/drivers/power/reset/reboot-mode.c b/drivers/power/reset/reboot-mode.c > index d033043f5250a4de152a7786ef37e88a0ace3bbb..f5ab6eab210bcd9670441a4d2a301d9efdf2f322 100644 > --- a/drivers/power/reset/reboot-mode.c > +++ b/drivers/power/reset/reboot-mode.c > @@ -19,12 +19,11 @@ > > struct mode_info { > const char *mode; > - u32 magic; > + u64 magic; > struct list_head list; > }; > > -static unsigned int get_reboot_mode_magic(struct reboot_mode_driver *reboot, > - const char *cmd) > +static u64 get_reboot_mode_magic(struct reboot_mode_driver *reboot, const char *cmd) > { > const char *normal = "normal"; > struct mode_info *info; > @@ -56,7 +55,7 @@ static int reboot_mode_notify(struct notifier_block *this, > unsigned long mode, void *cmd) > { > struct reboot_mode_driver *reboot; > - unsigned int magic; > + u64 magic; > > reboot = container_of(this, struct reboot_mode_driver, reboot_notifier); > magic = get_reboot_mode_magic(reboot, cmd); > @@ -78,7 +77,7 @@ int reboot_mode_register(struct reboot_mode_driver *reboot) > struct property *prop; > struct device_node *np = reboot->dev->of_node; > size_t len = strlen(PREFIX); > - u32 magic; > + u32 magic[2] = {0}; > int ret; > > INIT_LIST_HEAD(&reboot->head); > @@ -87,7 +86,10 @@ int reboot_mode_register(struct reboot_mode_driver *reboot) > if (strncmp(prop->name, PREFIX, len)) > continue; > > - if (device_property_read_u32(reboot->dev, prop->name, &magic)) { > + size_t count = device_property_count_u32(reboot->dev, prop->name); > + > + if (!count || count > ARRAY_SIZE(magic) || > + device_property_read_u32_array(reboot->dev, prop->name, magic, count)) { > pr_debug("reboot mode %s without magic number\n", prop->name); > continue; > } > @@ -98,7 +100,7 @@ int reboot_mode_register(struct reboot_mode_driver *reboot) > goto error; > } > > - info->magic = magic; > + info->magic = REBOOT_MODE_MAGIC(magic[0], magic[1]); > info->mode = kstrdup_const(prop->name + len, GFP_KERNEL); > if (!info->mode) { > ret = -ENOMEM; > diff --git a/drivers/power/reset/syscon-reboot-mode.c b/drivers/power/reset/syscon-reboot-mode.c > index e0772c9f70f7a19cd8ec8a0b7fdbbaa7ba44afd0..9f4b18c5e46f6a8bf197773ceceb80b250f57541 100644 > --- a/drivers/power/reset/syscon-reboot-mode.c > +++ b/drivers/power/reset/syscon-reboot-mode.c > @@ -20,16 +20,16 @@ struct syscon_reboot_mode { > u32 mask; > }; > > -static int syscon_reboot_mode_write(struct reboot_mode_driver *reboot, > - unsigned int magic) > +static int syscon_reboot_mode_write(struct reboot_mode_driver *reboot, u64 magic) > { > struct syscon_reboot_mode *syscon_rbm; > + u32 magic_arg1 = REBOOT_MODE_ARG1(magic); > int ret; > > syscon_rbm = container_of(reboot, struct syscon_reboot_mode, reboot); > > ret = regmap_update_bits(syscon_rbm->map, syscon_rbm->offset, > - syscon_rbm->mask, magic); > + syscon_rbm->mask, magic_arg1); > if (ret < 0) > dev_err(reboot->dev, "update reboot mode bits failed\n"); > > diff --git a/include/linux/reboot-mode.h b/include/linux/reboot-mode.h > index 4a2abb38d1d612ec0fdf05eb18c98b210f631b7f..2ce189fdfff4b396d7cc6f175b30016781ae4fe9 100644 > --- a/include/linux/reboot-mode.h > +++ b/include/linux/reboot-mode.h > @@ -2,10 +2,23 @@ > #ifndef __REBOOT_MODE_H__ > #define __REBOOT_MODE_H__ > > +#include > +#include > +#include > + > +/* Construct 64-bit reboot magic: arg2 in upper 32 bits, arg1 in lower 32 */ > +#define REBOOT_MODE_MAGIC(arg1, arg2) \ > + (FIELD_PREP(GENMASK_ULL(31, 0), (arg1)) | \ > + FIELD_PREP(GENMASK_ULL(63, 32), (arg2))) > +/* Get 32 bit arg1 from 64 bit magic */ > +#define REBOOT_MODE_ARG1(magic) FIELD_GET(GENMASK_ULL(31, 0), magic) > +/* Get 32 bit arg2 from 64 bit magic */ > +#define REBOOT_MODE_ARG2(magic) FIELD_GET(GENMASK_ULL(63, 32), magic) > + > struct reboot_mode_driver { > struct device *dev; > struct list_head head; > - int (*write)(struct reboot_mode_driver *reboot, unsigned int magic); > + int (*write)(struct reboot_mode_driver *reboot, u64 magic); > struct notifier_block reboot_notifier; > }; > > > -- > 2.34.1 >