Am 6. September 2021 07:22:21 MESZ schrieb Bin Meng <bmeng...@gmail.com>: >On Mon, Sep 6, 2021 at 12:45 PM Heinrich Schuchardt <xypron.g...@gmx.de> wrote: >> >> Am 6. September 2021 03:47:39 MESZ schrieb Bin Meng <bmeng...@gmail.com>: >> >On Mon, Sep 6, 2021 at 1:21 AM Heinrich Schuchardt <xypron.g...@gmx.de> >> >wrote: >> >> >> >> On 9/5/21 7:00 PM, Bin Meng wrote: >> >> > Hi Heinrich, >> >> > >> >> > On Mon, Sep 6, 2021 at 12:50 AM Heinrich Schuchardt >> >> > <xypron.g...@gmx.de> wrote: >> >> >> >> >> >> On 9/5/21 1:59 PM, Bin Meng wrote: >> >> >>> On Sun, Sep 5, 2021 at 4:38 PM Heinrich Schuchardt >> >> >>> <xypron.g...@gmx.de> wrote: >> >> >>>> >> >> >>>> Provide sysreset driver using the SBI system reset extension. >> >> >>>> >> >> >>> >> >> >>> This patch should be split into 2 patches, one for adding the sysreset >> >> >>> DM driver, and the other one for EFI support. >> >> >>> >> >> >>>> Signed-off-by: Heinrich Schuchardt <xypron.g...@gmx.de> >> >> >>>> --- >> >> >>>> v3: >> >> >>>> no change >> >> >>>> --- >> >> >>>> MAINTAINERS | 1 + >> >> >>>> arch/riscv/cpu/cpu.c | 13 ++++- >> >> >>>> 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 | 96 >> >> >>>> +++++++++++++++++++++++++++++++++ >> >> >>>> lib/efi_loader/Kconfig | 2 +- >> >> >>>> 8 files changed, 140 insertions(+), 6 deletions(-) >> >> >>>> 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 e9caa78d17..69cddda245 100644 >> >> >>>> --- a/arch/riscv/include/asm/sbi.h >> >> >>>> +++ b/arch/riscv/include/asm/sbi.h >> >> >>>> @@ -154,5 +154,6 @@ 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 ac77ffbc8b..6782331181 100644 >> >> >>>> --- a/drivers/sysreset/Kconfig >> >> >>>> +++ b/drivers/sysreset/Kconfig >> >> >>>> @@ -85,6 +85,17 @@ 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 implementation 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..fec5a66515 >> >> >>>> --- /dev/null >> >> >>>> +++ b/drivers/sysreset/sysreset_sbi.c >> >> >>>> @@ -0,0 +1,96 @@ >> >> >>>> +// SPDX-License-Identifier: GPL-2.0+ >> >> >>>> +/* >> >> >>>> + * Copyright 2021, Heinrich Schuchardt <xypron.g...@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; >> >> >>>> + >> >> >>>> + 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; >> >> >>>> +} >> >> >>> >> >> >>> Is there a better place for the EFI stuff? >> >> >> >> >> >> Bin, thanks for reviewing the series. >> >> >> >> >> >> This seems to be related to you comment above about splitting into two >> >> >> patches. >> >> > >> >> > Yep. >> >> > >> >> >> We put have the same set of EFI runtime functions for system >> >> >> reset in: >> >> >> >> >> >> drivers/sysreset/sysreset_x86.c >> >> >> drivers/firmware/psci.c >> >> >> arch/arm/mach-bcm283x/reset.c >> >> >> arch/arm/cpu/armv8/fsl-layerscape/cpu.c >> >> > >> >> > I didn't realize that. But this does not look correct to me. >> >> > >> >> > EFI reset should be independent of the system reset drivers. For >> >> > example, on RISC-V SRST is optional so not every SBI implements this. >> >> > On SiFive Unleashed, the "gpio-restart" driver is used for reset (see >> >> > sysreset_gpio.c). >> >> >> >> The EFI functions that you see in this patch are for the runtime, i.e. >> >> after ExitBootServices(). >> >> >> >> When you issue the reboot or poweroff command in Linux it will call the >> >> UEFI runtime. At this point all driver model code is gone. So we cannot >> >> call any DM U-Boot driver. This is why these two functions are marked as >> >> __efi_runtime. >> >> When using a system with multiple GiB of memory one could argue that freeing >> a MiB of boottime U-Boot memory at ExitBootServices is not worth the effort. >> >> On the other side having a very small runtime to consider for security >> analysis also has its merrits. > >Agree, but my point is that current U-Boot EFI loader approach of >marking runtime functions with __efi_runtime is not scalable. You have >to trace down all callees to make sure they are marked with >__efi_runtime by an __efi_runtime caller, like you did in this patch. >But my test on EFI loader on x86 Linux in the past suggested that we >missed something in the calling path. > >> Using platform independent reset methods like PSCI and SBI allows to limit >> the runtime code base. We should avoid board specific code. > >There are platforms without PSCI and SBI but want EFI support. > >> But could you, please, answer my original question: Where do you want the >> SBI runtime code placed? >> > >I still think we should implement the EFI reset via DM APIs, so as I >mentioned the runtime codes can be put in the common efi_loader >directory.
After ExitBootServices Linux calls SetVirtualAdressMap. The DM code would have to update all pointers it uses afterwards according to Linux' memory mapping. So instead of spreading __efi_runtime you will be spreading pointer update code. This will lead to an increase of the U-Boot binary size for all boards and add complexity. I am in doubt here. Best regards Heinrich
