This series adds SBI SRST extension support to Linux RISC-V.
These patches can be found in riscv_sbi_srst_v6 branch at:
https://github.com/avpatel/linux
Changes since v5:
- Factored-out pr_info() related change into separate patch
- Added cover letter
Changes since v4:
- We should compare both major and minor number to ensure that
SBI spec version is 0.3 (or above) for detecting SRST extension.
Changes since v3:
- Rebased on Linux-5.12-rc1
- Check SBI spec version when probing for SRST extension
Changes since v2:
- Rebased on Linux-5.10-rc5
- Updated patch as-per SBI SRST extension available in the latest
SBI v0.3-draft specification
Changes since v1:
- Updated patch as-per latest SBI SRST extension draft spec where
we have only one SBI call with "reset_type" parameter
Anup Patel (2):
RISC-V: Don't print SBI version for all detected extensions
RISC-V: Use SBI SRST extension when available
arch/riscv/include/asm/sbi.h | 24 +++++++++++++++++++++
arch/riscv/kernel/sbi.c | 41 +++++++++++++++++++++++++++++++++---
2 files changed, 62 insertions(+), 3 deletions(-)
--
2.25.1
The SBI SRST extension provides a standard way to poweroff and
reboot the system irrespective to whether Linux RISC-V S-mode
is running natively (HS-mode) or inside Guest/VM (VS-mode).
The SBI SRST extension is available in latest SBI v0.3-draft
specification at: https://github.com/riscv/riscv-sbi-doc.
This patch extends Linux RISC-V SBI implementation to detect
and use SBI SRST extension.
Signed-off-by: Anup Patel <[email protected]>
Reviewed-by: Atish Patra <[email protected]>
---
arch/riscv/include/asm/sbi.h | 24 ++++++++++++++++++++++++
arch/riscv/kernel/sbi.c | 35 +++++++++++++++++++++++++++++++++++
2 files changed, 59 insertions(+)
diff --git a/arch/riscv/include/asm/sbi.h b/arch/riscv/include/asm/sbi.h
index 99895d9c3bdd..79fa9f28b786 100644
--- a/arch/riscv/include/asm/sbi.h
+++ b/arch/riscv/include/asm/sbi.h
@@ -27,6 +27,7 @@ enum sbi_ext_id {
SBI_EXT_IPI = 0x735049,
SBI_EXT_RFENCE = 0x52464E43,
SBI_EXT_HSM = 0x48534D,
+ SBI_EXT_SRST = 0x53525354,
};
enum sbi_ext_base_fid {
@@ -70,6 +71,21 @@ enum sbi_hsm_hart_status {
SBI_HSM_HART_STATUS_STOP_PENDING,
};
+enum sbi_ext_srst_fid {
+ SBI_EXT_SRST_RESET = 0,
+};
+
+enum sbi_srst_reset_type {
+ SBI_SRST_RESET_TYPE_SHUTDOWN = 0,
+ SBI_SRST_RESET_TYPE_COLD_REBOOT,
+ SBI_SRST_RESET_TYPE_WARM_REBOOT,
+};
+
+enum sbi_srst_reset_reason {
+ SBI_SRST_RESET_REASON_NONE = 0,
+ SBI_SRST_RESET_REASON_SYS_FAILURE,
+};
+
#define SBI_SPEC_VERSION_DEFAULT 0x1
#define SBI_SPEC_VERSION_MAJOR_SHIFT 24
#define SBI_SPEC_VERSION_MAJOR_MASK 0x7f
@@ -145,6 +161,14 @@ static inline unsigned long sbi_minor_version(void)
return sbi_spec_version & SBI_SPEC_VERSION_MINOR_MASK;
}
+/* Make SBI version */
+static inline unsigned long sbi_mk_version(unsigned long major,
+ unsigned long minor)
+{
+ return ((major & SBI_SPEC_VERSION_MAJOR_MASK) <<
+ SBI_SPEC_VERSION_MAJOR_SHIFT) | minor;
+}
+
int sbi_err_map_linux_errno(int err);
#else /* CONFIG_RISCV_SBI */
static inline int sbi_remote_fence_i(const unsigned long *hart_mask) { return -1; }
diff --git a/arch/riscv/kernel/sbi.c b/arch/riscv/kernel/sbi.c
index c0dcebdd30ec..e94ea8053984 100644
--- a/arch/riscv/kernel/sbi.c
+++ b/arch/riscv/kernel/sbi.c
@@ -7,6 +7,7 @@
#include <linux/init.h>
#include <linux/pm.h>
+#include <linux/reboot.h>
#include <asm/sbi.h>
#include <asm/smp.h>
@@ -501,6 +502,32 @@ int sbi_remote_hfence_vvma_asid(const unsigned long *hart_mask,
}
EXPORT_SYMBOL(sbi_remote_hfence_vvma_asid);
+static void sbi_srst_reset(unsigned long type, unsigned long reason)
+{
+ sbi_ecall(SBI_EXT_SRST, SBI_EXT_SRST_RESET, type, reason,
+ 0, 0, 0, 0);
+ pr_warn("%s: type=0x%lx reason=0x%lx failed\n",
+ __func__, type, reason);
+}
+
+static int sbi_srst_reboot(struct notifier_block *this,
+ unsigned long mode, void *cmd)
+{
+ sbi_srst_reset((mode == REBOOT_WARM || mode == REBOOT_SOFT) ?
+ SBI_SRST_RESET_TYPE_WARM_REBOOT :
+ SBI_SRST_RESET_TYPE_COLD_REBOOT,
+ SBI_SRST_RESET_REASON_NONE);
+ return NOTIFY_DONE;
+}
+
+static struct notifier_block sbi_srst_reboot_nb;
+
+static void sbi_srst_power_off(void)
+{
+ sbi_srst_reset(SBI_SRST_RESET_TYPE_SHUTDOWN,
+ SBI_SRST_RESET_REASON_NONE);
+}
+
/**
* sbi_probe_extension() - Check if an SBI extension ID is supported or not.
* @extid: The extension ID to be probed.
@@ -593,6 +620,14 @@ void __init sbi_init(void)
} else {
__sbi_rfence = __sbi_rfence_v01;
}
+ if ((sbi_spec_version >= sbi_mk_version(0, 3)) &&
+ (sbi_probe_extension(SBI_EXT_SRST) > 0)) {
+ pr_info("SBI SRST extension detected\n");
+ pm_power_off = sbi_srst_power_off;
+ sbi_srst_reboot_nb.notifier_call = sbi_srst_reboot;
+ sbi_srst_reboot_nb.priority = 192;
+ register_restart_handler(&sbi_srst_reboot_nb);
+ }
} else {
__sbi_set_timer = __sbi_set_timer_v01;
__sbi_send_ipi = __sbi_send_ipi_v01;
--
2.25.1
The sbi_init() already prints SBI version before detecting
various SBI extensions so we don't need to print SBI version
for all detected SBI extensions.
Signed-off-by: Anup Patel <[email protected]>
---
arch/riscv/kernel/sbi.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/arch/riscv/kernel/sbi.c b/arch/riscv/kernel/sbi.c
index f4a7db3d309e..c0dcebdd30ec 100644
--- a/arch/riscv/kernel/sbi.c
+++ b/arch/riscv/kernel/sbi.c
@@ -577,19 +577,19 @@ void __init sbi_init(void)
sbi_get_firmware_id(), sbi_get_firmware_version());
if (sbi_probe_extension(SBI_EXT_TIME) > 0) {
__sbi_set_timer = __sbi_set_timer_v02;
- pr_info("SBI v0.2 TIME extension detected\n");
+ pr_info("SBI TIME extension detected\n");
} else {
__sbi_set_timer = __sbi_set_timer_v01;
}
if (sbi_probe_extension(SBI_EXT_IPI) > 0) {
__sbi_send_ipi = __sbi_send_ipi_v02;
- pr_info("SBI v0.2 IPI extension detected\n");
+ pr_info("SBI IPI extension detected\n");
} else {
__sbi_send_ipi = __sbi_send_ipi_v01;
}
if (sbi_probe_extension(SBI_EXT_RFENCE) > 0) {
__sbi_rfence = __sbi_rfence_v02;
- pr_info("SBI v0.2 RFENCE extension detected\n");
+ pr_info("SBI RFENCE extension detected\n");
} else {
__sbi_rfence = __sbi_rfence_v01;
}
--
2.25.1
On Mon, Mar 15, 2021 at 4:07 AM Anup Patel <[email protected]> wrote:
>
> The sbi_init() already prints SBI version before detecting
> various SBI extensions so we don't need to print SBI version
> for all detected SBI extensions.
>
> Signed-off-by: Anup Patel <[email protected]>
> ---
> arch/riscv/kernel/sbi.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/arch/riscv/kernel/sbi.c b/arch/riscv/kernel/sbi.c
> index f4a7db3d309e..c0dcebdd30ec 100644
> --- a/arch/riscv/kernel/sbi.c
> +++ b/arch/riscv/kernel/sbi.c
> @@ -577,19 +577,19 @@ void __init sbi_init(void)
> sbi_get_firmware_id(), sbi_get_firmware_version());
> if (sbi_probe_extension(SBI_EXT_TIME) > 0) {
> __sbi_set_timer = __sbi_set_timer_v02;
> - pr_info("SBI v0.2 TIME extension detected\n");
> + pr_info("SBI TIME extension detected\n");
> } else {
> __sbi_set_timer = __sbi_set_timer_v01;
> }
> if (sbi_probe_extension(SBI_EXT_IPI) > 0) {
> __sbi_send_ipi = __sbi_send_ipi_v02;
> - pr_info("SBI v0.2 IPI extension detected\n");
> + pr_info("SBI IPI extension detected\n");
> } else {
> __sbi_send_ipi = __sbi_send_ipi_v01;
> }
> if (sbi_probe_extension(SBI_EXT_RFENCE) > 0) {
> __sbi_rfence = __sbi_rfence_v02;
> - pr_info("SBI v0.2 RFENCE extension detected\n");
> + pr_info("SBI RFENCE extension detected\n");
> } else {
> __sbi_rfence = __sbi_rfence_v01;
> }
> --
> 2.25.1
>
>
> _______________________________________________
> linux-riscv mailing list
> [email protected]
> http://lists.infradead.org/mailman/listinfo/linux-riscv
Reviewed-by: Atish Patra <[email protected]>
--
Regards,
Atish
On Mon, 15 Mar 2021 04:04:59 PDT (-0700), Anup Patel wrote:
> The sbi_init() already prints SBI version before detecting
> various SBI extensions so we don't need to print SBI version
> for all detected SBI extensions.
>
> Signed-off-by: Anup Patel <[email protected]>
> ---
> arch/riscv/kernel/sbi.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/arch/riscv/kernel/sbi.c b/arch/riscv/kernel/sbi.c
> index f4a7db3d309e..c0dcebdd30ec 100644
> --- a/arch/riscv/kernel/sbi.c
> +++ b/arch/riscv/kernel/sbi.c
> @@ -577,19 +577,19 @@ void __init sbi_init(void)
> sbi_get_firmware_id(), sbi_get_firmware_version());
> if (sbi_probe_extension(SBI_EXT_TIME) > 0) {
> __sbi_set_timer = __sbi_set_timer_v02;
> - pr_info("SBI v0.2 TIME extension detected\n");
> + pr_info("SBI TIME extension detected\n");
> } else {
> __sbi_set_timer = __sbi_set_timer_v01;
> }
> if (sbi_probe_extension(SBI_EXT_IPI) > 0) {
> __sbi_send_ipi = __sbi_send_ipi_v02;
> - pr_info("SBI v0.2 IPI extension detected\n");
> + pr_info("SBI IPI extension detected\n");
> } else {
> __sbi_send_ipi = __sbi_send_ipi_v01;
> }
> if (sbi_probe_extension(SBI_EXT_RFENCE) > 0) {
> __sbi_rfence = __sbi_rfence_v02;
> - pr_info("SBI v0.2 RFENCE extension detected\n");
> + pr_info("SBI RFENCE extension detected\n");
> } else {
> __sbi_rfence = __sbi_rfence_v01;
> }
Thanks. I'm just putting this one on for-next so you don't have to carry
around the diff.
On Wed, Mar 17, 2021 at 10:38 AM Palmer Dabbelt <[email protected]> wrote:
>
> On Mon, 15 Mar 2021 04:04:59 PDT (-0700), Anup Patel wrote:
> > The sbi_init() already prints SBI version before detecting
> > various SBI extensions so we don't need to print SBI version
> > for all detected SBI extensions.
> >
> > Signed-off-by: Anup Patel <[email protected]>
> > ---
> > arch/riscv/kernel/sbi.c | 6 +++---
> > 1 file changed, 3 insertions(+), 3 deletions(-)
> >
> > diff --git a/arch/riscv/kernel/sbi.c b/arch/riscv/kernel/sbi.c
> > index f4a7db3d309e..c0dcebdd30ec 100644
> > --- a/arch/riscv/kernel/sbi.c
> > +++ b/arch/riscv/kernel/sbi.c
> > @@ -577,19 +577,19 @@ void __init sbi_init(void)
> > sbi_get_firmware_id(), sbi_get_firmware_version());
> > if (sbi_probe_extension(SBI_EXT_TIME) > 0) {
> > __sbi_set_timer = __sbi_set_timer_v02;
> > - pr_info("SBI v0.2 TIME extension detected\n");
> > + pr_info("SBI TIME extension detected\n");
> > } else {
> > __sbi_set_timer = __sbi_set_timer_v01;
> > }
> > if (sbi_probe_extension(SBI_EXT_IPI) > 0) {
> > __sbi_send_ipi = __sbi_send_ipi_v02;
> > - pr_info("SBI v0.2 IPI extension detected\n");
> > + pr_info("SBI IPI extension detected\n");
> > } else {
> > __sbi_send_ipi = __sbi_send_ipi_v01;
> > }
> > if (sbi_probe_extension(SBI_EXT_RFENCE) > 0) {
> > __sbi_rfence = __sbi_rfence_v02;
> > - pr_info("SBI v0.2 RFENCE extension detected\n");
> > + pr_info("SBI RFENCE extension detected\n");
> > } else {
> > __sbi_rfence = __sbi_rfence_v01;
> > }
>
> Thanks. I'm just putting this one on for-next so you don't have to carry
> around the diff.
Thanks Palmer.