On 3/5/21 12:50 AM, Sean Anderson wrote:
On 3/4/21 12:00 PM, Heinrich Schuchardt wrote:
Provide sysreset driver using the SBI system reset extension.
Signed-off-by: Heinrich Schuchardt xypron.glpk@gmx.de
MAINTAINERS | 1 + arch/riscv/include/asm/sbi.h | 1 + arch/riscv/lib/sbi.c | 21 +++++-- drivers/sysreset/Kconfig | 11 ++++ drivers/sysreset/Makefile | 1 + drivers/sysreset/sysreset_sbi.c | 102 ++++++++++++++++++++++++++++++++ lib/efi_loader/Kconfig | 2 +- 7 files changed, 134 insertions(+), 5 deletions(-) create mode 100644 drivers/sysreset/sysreset_sbi.c
diff --git a/MAINTAINERS b/MAINTAINERS index de499940e5..192db06ff9 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -985,6 +985,7 @@ T: git https://source.denx.de/u-boot/custodians/u-boot-riscv.git F: arch/riscv/ F: cmd/riscv/ F: doc/usage/sbi.rst +F: drivers/sysreset/sysreset_sbi.c F: drivers/timer/andes_plmt_timer.c F: drivers/timer/sifive_clint_timer.c F: tools/prelink-riscv.c diff --git a/arch/riscv/include/asm/sbi.h b/arch/riscv/include/asm/sbi.h index c598bb11ce..058e2e23a8 100644 --- a/arch/riscv/include/asm/sbi.h +++ b/arch/riscv/include/asm/sbi.h @@ -150,5 +150,6 @@ void sbi_set_timer(uint64_t stime_value); long sbi_get_spec_version(void); int sbi_get_impl_id(void); int sbi_probe_extension(int ext); +void sbi_srst_reset(unsigned long type, unsigned long reason);
#endif diff --git a/arch/riscv/lib/sbi.c b/arch/riscv/lib/sbi.c index 77845a73ca..8508041f2a 100644 --- a/arch/riscv/lib/sbi.c +++ b/arch/riscv/lib/sbi.c @@ -8,13 +8,14 @@ */
#include <common.h> +#include <efi_loader.h> #include <asm/encoding.h> #include <asm/sbi.h>
-struct sbiret sbi_ecall(int ext, int fid, unsigned long arg0, - unsigned long arg1, unsigned long arg2, - unsigned long arg3, unsigned long arg4, - unsigned long arg5) +struct sbiret __efi_runtime sbi_ecall(int ext, int fid, unsigned long arg0, + unsigned long arg1, unsigned long arg2, + unsigned long arg3, unsigned long arg4, + unsigned long arg5) { struct sbiret ret;
@@ -108,6 +109,18 @@ int sbi_probe_extension(int extid) return -ENOTSUPP; }
+/**
- sbi_srst_reset() - invoke system reset extension
- @type: type of reset
- @reason: reason for reset
- */
+void __efi_runtime sbi_srst_reset(unsigned long type, unsigned long reason) +{ + sbi_ecall(SBI_EXT_SRST, SBI_EXT_SRST_RESET, type, reason, + 0, 0, 0, 0); +}
#ifdef CONFIG_SBI_V01
/** diff --git a/drivers/sysreset/Kconfig b/drivers/sysreset/Kconfig index 0e5c7c9971..05a7e26300 100644 --- a/drivers/sysreset/Kconfig +++ b/drivers/sysreset/Kconfig @@ -79,6 +79,17 @@ config SYSRESET_PSCI Enable PSCI SYSTEM_RESET function call. To use this, PSCI firmware must be running on your system.
+config SYSRESET_SBI + bool "Enable support for SBI System Reset" + depends on RISCV_SMODE && SBI_V02 + select SYSRESET_CMD_POWEROFF if CMD_POWEROFF + help + Enable system reset and poweroff via the SBI system reset extension. + If the SBI implemention provides the extension, is board specific. + The extension was introduced in version 0.3 of the SBI specification. + The SBI system reset driver supports the UEFI ResetSystem() service + at runtime.
config SYSRESET_SOCFPGA bool "Enable support for Intel SOCFPGA family" depends on ARCH_SOCFPGA && (TARGET_SOCFPGA_GEN5 || TARGET_SOCFPGA_ARRIA10) diff --git a/drivers/sysreset/Makefile b/drivers/sysreset/Makefile index de81c399d7..8e00be0779 100644 --- a/drivers/sysreset/Makefile +++ b/drivers/sysreset/Makefile @@ -13,6 +13,7 @@ obj-$(CONFIG_SYSRESET_MPC83XX) += sysreset_mpc83xx.o obj-$(CONFIG_SYSRESET_MICROBLAZE) += sysreset_microblaze.o obj-$(CONFIG_SYSRESET_OCTEON) += sysreset_octeon.o obj-$(CONFIG_SYSRESET_PSCI) += sysreset_psci.o +obj-$(CONFIG_SYSRESET_SBI) += sysreset_sbi.o obj-$(CONFIG_SYSRESET_SOCFPGA) += sysreset_socfpga.o obj-$(CONFIG_SYSRESET_SOCFPGA_SOC64) += sysreset_socfpga_soc64.o obj-$(CONFIG_SYSRESET_TI_SCI) += sysreset-ti-sci.o diff --git a/drivers/sysreset/sysreset_sbi.c b/drivers/sysreset/sysreset_sbi.c new file mode 100644 index 0000000000..87fbc3ea3e --- /dev/null +++ b/drivers/sysreset/sysreset_sbi.c @@ -0,0 +1,102 @@ +// SPDX-License-Identifier: GPL-2.0+ +/*
- Copyright 2021, Heinrich Schuchardt xypron.glpk@gmx.de
- */
+#include <common.h> +#include <dm.h> +#include <errno.h> +#include <efi_loader.h> +#include <log.h> +#include <sysreset.h> +#include <asm/sbi.h>
+static long __efi_runtime_data have_reset;
+static int sbi_sysreset_request(struct udevice *dev, enum sysreset_t type) +{ + enum sbi_srst_reset_type reset_type;
+ if (!have_reset) + return -ENOENT;
Is this necessary? This should never be called if there is no reset, since we just fail to probe.
Thank you for reviewing.
Yes, we can skip it.
+ switch (type) { + case SYSRESET_WARM: + reset_type = SBI_SRST_RESET_TYPE_WARM_REBOOT; + break; + case SYSRESET_COLD: + reset_type = SBI_SRST_RESET_TYPE_COLD_REBOOT; + break; + case SYSRESET_POWER_OFF: + reset_type = SBI_SRST_RESET_TYPE_SHUTDOWN; + break; + default: + log_err("SBI has no system reset extension\n"); + return -ENOSYS; + }
+ sbi_srst_reset(reset_type, SBI_SRST_RESET_REASON_NONE);
+ return -EINPROGRESS; +}
+efi_status_t efi_reset_system_init(void) +{ + return EFI_SUCCESS; +}
+void __efi_runtime EFIAPI efi_reset_system(enum efi_reset_type type, + efi_status_t reset_status, + unsigned long data_size, + void *reset_data)
As an aside, is there a reason why the generic (weak) efi_reset_system does not just call sysreset_walk_halt(type)?
efi_reset_system is invoked at UEFI runtime. Most functions of U-Boot are no longer in memory after ExitBootServices(). Only functions in the __efi_runtime section may be called.
+{ + enum sbi_srst_reset_type reset_type;
+ if (have_reset) + switch (type) { + case SYSRESET_WARM: + reset_type = SBI_SRST_RESET_TYPE_WARM_REBOOT; + break; + case SYSRESET_COLD: + reset_type = SBI_SRST_RESET_TYPE_COLD_REBOOT; + break; + case SYSRESET_POWER_OFF: + reset_type = SBI_SRST_RESET_TYPE_SHUTDOWN; + break; + default: + goto hang;
Why do we hang by default? For comparison, sysreset_x86 has
if (reset_type == EFI_RESET_COLD || reset_type == EFI_RESET_PLATFORM_SPECIFIC) value = SYS_RST | RST_CPU | FULL_RST; else /* assume EFI_RESET_WARM since we cannot return an error */ value = SYS_RST | RST_CPU;
ok
+ }
+ sbi_srst_reset(reset_type, SBI_SRST_RESET_REASON_NONE);
Should we instead do
enum sbi_srst_reset_reason reset_reason; if (reset_status == EFI_SUCCESS) reset_reason = SBI_SRST_RESET_REASON_NONE; else reset_reason = SBI_SRST_RESET_REASON_SYS_FAILURE; sbi_srst_reset(reset_type, reset_status == EFI_SUCCESS ? SBI_SRST_RESET_REASON_NONE : SBI_SRST_RESET_REASON_SYS_FAILURE);
since we have reset status available?
Makes sense.
+hang: + while (1) + ; +}
+static int sbi_sysreset_probe(struct udevice *dev) +{ + have_reset = sbi_probe_extension(SBI_EXT_SRST); + if (have_reset) + return 0;
+ log_err("SBI has no system reset extension\n");
Is this an error? It's perfectly normal for SBI implementations to lack support for some extensions. Perhaps a warning/info would be better.
We shouldn't have chosen this driver in the configuration if the SBI does not support it.
I will change this to a warning.
+ return -ENOENT; +}
+static const struct udevice_id sbi_sysreset_ids[] = { + { .compatible = "riscv" },
This compatible string is already in-use for RISC-V CPUs. And if this isn't supposed to have a device tree binding, do we even need of_match?
I discussed this with Simon in
https://lists.denx.de/pipermail/u-boot/2021-March/443270.html
Instead of adding code to the board files we should have a device-tree node. A reasonable compatible string would be "riscv,sbi-sysreset".
+ { } +};
+static struct sysreset_ops sbi_sysreset_ops = { + .request = sbi_sysreset_request, +};
+U_BOOT_DRIVER(sbi_sysreset) = { + .name = "sbi-sysreset", + .id = UCLASS_SYSRESET, + .of_match = sbi_sysreset_ids, + .ops = &sbi_sysreset_ops, + .probe = sbi_sysreset_probe, +}; diff --git a/lib/efi_loader/Kconfig b/lib/efi_loader/Kconfig index e729f727df..7e76435339 100644 --- a/lib/efi_loader/Kconfig +++ b/lib/efi_loader/Kconfig @@ -277,7 +277,7 @@ config EFI_HAVE_RUNTIME_RESET bool default y depends on ARCH_BCM283X || FSL_LAYERSCAPE || PSCI_RESET || \ - SANDBOX || SYSRESET_X86 + SANDBOX || SYSRESET_SBI || SYSRESET_X86
As a general note, perhaps it is better to set this from other Kconfigs? How long will this list get?
This seems to be a matter of taste.
Best regards
Heinrich
--Sean
config EFI_GRUB_ARM32_WORKAROUND bool "Workaround for GRUB on 32bit ARM" -- 2.30.1