Re: [PATCH v5 3/4] sysreset: provide SBI based sysreset driver

On 9/10/21 10:15 AM, Heinrich Schuchardt wrote:

Provide sysreset driver using the SBI system reset extension.

Signed-off-by: Heinrich Schuchardt heinrich.schuchardt@canonical.com

v5:

• don't add __efi_runtime
• use '=' not ':' in array initialization with enum indices

v4:

• remove the UEFI SystemReset() implementation
• simplify the code using an array to translate reset types
• remove a superfluos check to determine if the device was probed

---

MAINTAINERS | 1 + arch/riscv/cpu/cpu.c | 13 ++++++++- arch/riscv/include/asm/sbi.h | 1 + arch/riscv/lib/sbi.c | 12 ++++++++ drivers/sysreset/Kconfig | 12 ++++++++ drivers/sysreset/Makefile | 1 + drivers/sysreset/sysreset_sbi.c | 51 +++++++++++++++++++++++++++++++++ 7 files changed, 90 insertions(+), 1 deletion(-) create mode 100644 drivers/sysreset/sysreset_sbi.c

diff --git a/MAINTAINERS b/MAINTAINERS index 4cf0c33c5d..88d7aa2bc7 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -1017,6 +1017,7 @@ 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/cpu/cpu.c b/arch/riscv/cpu/cpu.c index c894ac10b5..8e49b6d736 100644 --- a/arch/riscv/cpu/cpu.c +++ b/arch/riscv/cpu/cpu.c @@ -6,6 +6,7 @@ #include <common.h> #include <cpu.h> #include <dm.h> +#include <dm/lists.h> #include <init.h> #include <log.h> #include <asm/encoding.h> @@ -138,7 +139,17 @@ int arch_cpu_init_dm(void)

int arch_early_init_r(void) {

• return riscv_cpu_probe();

• int ret;

• ret = riscv_cpu_probe();

• if (ret)

• return ret;
  

• if (IS_ENABLED(CONFIG_SYSRESET_SBI))

• device_bind_driver(gd->dm_root, "sbi-sysreset",
  

• 		   "sbi-sysreset", NULL);
  

• return 0; }

  /**

diff --git a/arch/riscv/include/asm/sbi.h b/arch/riscv/include/asm/sbi.h index 34a115afc3..5030892b47 100644 --- a/arch/riscv/include/asm/sbi.h +++ b/arch/riscv/include/asm/sbi.h @@ -153,5 +153,6 @@ 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..2b53896b8a 100644 --- a/arch/riscv/lib/sbi.c +++ b/arch/riscv/lib/sbi.c @@ -108,6 +108,18 @@ int sbi_probe_extension(int extid) return -ENOTSUPP; }

+/**

• • sbi_srst_reset() - invoke system reset extension
• • @type: type of reset
• • @reason: reason for reset
• */

+void 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 ac77ffbc8b..43a948cfcd 100644 --- a/drivers/sysreset/Kconfig +++ b/drivers/sysreset/Kconfig @@ -85,6 +85,18 @@ 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.
  

•  The extension was introduced in version 0.3 of the SBI specification.
  

•  If the SBI implementation provides the extension, is board specific.
  

•  The RISC-V platform specification mandates the extension for rich
  

•  operating system platforms.
  

• 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..5e8090d62b --- /dev/null +++ b/drivers/sysreset/sysreset_sbi.c @@ -0,0 +1,51 @@ +// SPDX-License-Identifier: GPL-2.0+ +/*

• • Copyright 2021, Heinrich Schuchardt heinrich.schuchardt@canonical.com
• */

+#include <common.h> +#include <dm.h> +#include <errno.h> +#include <log.h> +#include <sysreset.h> +#include <asm/sbi.h>

+static enum sbi_srst_reset_type reset_type_map[SYSRESET_COUNT] = {

• [SYSRESET_WARM] = SBI_SRST_RESET_TYPE_WARM_REBOOT,
• [SYSRESET_COLD] = SBI_SRST_RESET_TYPE_COLD_REBOOT,
• [SYSRESET_POWER] = SBI_SRST_RESET_TYPE_COLD_REBOOT,
• [SYSRESET_POWER_OFF] = SBI_SRST_RESET_TYPE_SHUTDOWN,

+};

+static int sbi_sysreset_request(struct udevice *dev, enum sysreset_t type) +{

• enum sbi_srst_reset_type reset_type;
• reset_type = reset_type_map[type];
• sbi_srst_reset(reset_type, SBI_SRST_RESET_REASON_NONE);
• return -EINPROGRESS;

+}

+static int sbi_sysreset_probe(struct udevice *dev) +{

• long have_reset;
• have_reset = sbi_probe_extension(SBI_EXT_SRST);
• if (have_reset)

• return 0;
  

• log_warning("SBI has no system reset extension\n");
• return -ENOENT;

+}

+static struct sysreset_ops sbi_sysreset_ops = {

• .request = sbi_sysreset_request,

+};

+U_BOOT_DRIVER(sbi_sysreset) = {

• .name = "sbi-sysreset",
• .id = UCLASS_SYSRESET,
• .ops = &sbi_sysreset_ops,
• .probe = sbi_sysreset_probe,

+};

Reviewed-by: Sean Anderson seanga2@gmail.com