On 5/18/22 23:03, Ard Biesheuvel wrote:
On Wed, 18 May 2022 at 11:57, Sunil V L <sunilvl@xxxxxxxxxxxxxxxx> wrote:This patch adds the support for getting the boot hart ID in Linux EFI stub using RISCV_EFI_BOOT_PROTOCOL. This protocol is preferred method over existing DT based solution since it works irrespective of DT or ACPI. The specification of the protocol is hosted at: https://github.com/riscv-non-isa/riscv-uefi Signed-off-by: Sunil V L <sunilvl@xxxxxxxxxxxxxxxx> Acked-by: Palmer Dabbelt <palmer@xxxxxxxxxxxx> Reviewed-by: Heinrich Schuchardt <heinrich.schuchardt@xxxxxxxxxxxxx> --- drivers/firmware/efi/libstub/efistub.h | 7 ++++++ drivers/firmware/efi/libstub/riscv-stub.c | 29 +++++++++++++++++++---- include/linux/efi.h | 1 + 3 files changed, 32 insertions(+), 5 deletions(-) diff --git a/drivers/firmware/efi/libstub/efistub.h b/drivers/firmware/efi/libstub/efistub.h index edb77b0621ea..aced62a0907e 100644 --- a/drivers/firmware/efi/libstub/efistub.h +++ b/drivers/firmware/efi/libstub/efistub.h @@ -720,6 +720,13 @@ union efi_tcg2_protocol { } mixed_mode; }; +struct riscv_efi_boot_protocol { + u64 revision; + + efi_status_t (__efiapi * get_boot_hartid)(struct riscv_efi_boot_protocol *this, + size_t *boot_hartid);size_t is not a EFI type, and your spec uses UINTN here, which is equivalent to 'unsigned long'. However, jump_kernel_func() takes a unsigned int for the hartid. Please clean this up.
unsigned long and size_t have the same number of bits. This seems to be a question of taste where we should follow the maintainer.
jump_kernel_func() assuming boot hart ID to be an unsigned int is not in line with the RISC-V ISA which allows to use all xlen bits.
+}; + typedef union efi_load_file_protocol efi_load_file_protocol_t; typedef union efi_load_file_protocol efi_load_file2_protocol_t; diff --git a/drivers/firmware/efi/libstub/riscv-stub.c b/drivers/firmware/efi/libstub/riscv-stub.c index 9c460843442f..012504f6f9a4 100644 --- a/drivers/firmware/efi/libstub/riscv-stub.c +++ b/drivers/firmware/efi/libstub/riscv-stub.c @@ -23,7 +23,7 @@ typedef void __noreturn (*jump_kernel_func)(unsigned int, unsigned long); -static u32 hartid; +static size_t hartid;and herestatic int get_boot_hartid_from_fdt(void) { @@ -47,14 +47,33 @@ static int get_boot_hartid_from_fdt(void) return 0; } +static efi_status_t get_boot_hartid_from_efi(void) +{ + efi_guid_t boot_protocol_guid = RISCV_EFI_BOOT_PROTOCOL_GUID; + efi_status_t status; + struct riscv_efi_boot_protocol *boot_protocol; + + status = efi_bs_call(locate_protocol, &boot_protocol_guid, NULL, + (void **)&boot_protocol); + if (status == EFI_SUCCESS) { + status = efi_call_proto(boot_protocol, + get_boot_hartid, &hartid);
A lot of the kernel code seems to be unfit to handle hart IDs exceeding INT_MAX (e.g. sbi_cpu_is_stopped()). Until this is fixed we have to treat hartid > INT_MAX as an error.
Best regards Heinrich
+ } + return status; +} + efi_status_t check_platform_features(void) { int ret; + efi_status_t status; - ret = get_boot_hartid_from_fdt(); - if (ret) { - efi_err("/chosen/boot-hartid missing or invalid!\n"); - return EFI_UNSUPPORTED; + status = get_boot_hartid_from_efi(); + if (status != EFI_SUCCESS) { + ret = get_boot_hartid_from_fdt(); + if (ret) { + efi_err("Failed to get boot hartid!\n"); + return EFI_UNSUPPORTED; + } } return EFI_SUCCESS; } diff --git a/include/linux/efi.h b/include/linux/efi.h index ccd4d3f91c98..9822c730207c 100644 --- a/include/linux/efi.h +++ b/include/linux/efi.h @@ -380,6 +380,7 @@ void efi_native_runtime_setup(void); #define EFI_CONSOLE_OUT_DEVICE_GUID EFI_GUID(0xd3b36f2c, 0xd551, 0x11d4, 0x9a, 0x46, 0x00, 0x90, 0x27, 0x3f, 0xc1, 0x4d) #define APPLE_PROPERTIES_PROTOCOL_GUID EFI_GUID(0x91bd12fe, 0xf6c3, 0x44fb, 0xa5, 0xb7, 0x51, 0x22, 0xab, 0x30, 0x3a, 0xe0) #define EFI_TCG2_PROTOCOL_GUID EFI_GUID(0x607f766c, 0x7455, 0x42be, 0x93, 0x0b, 0xe4, 0xd7, 0x6d, 0xb2, 0x72, 0x0f) +#define RISCV_EFI_BOOT_PROTOCOL_GUID EFI_GUID(0xccd15fec, 0x6f73, 0x4eec, 0x83, 0x95, 0x3e, 0x69, 0xe4, 0xb9, 0x40, 0xbf) #define EFI_LOAD_FILE_PROTOCOL_GUID EFI_GUID(0x56ec3091, 0x954c, 0x11d2, 0x8e, 0x3f, 0x00, 0xa0, 0xc9, 0x69, 0x72, 0x3b) #define EFI_LOAD_FILE2_PROTOCOL_GUID EFI_GUID(0x4006c0c1, 0xfcb3, 0x403e, 0x99, 0x6d, 0x4a, 0x6c, 0x87, 0x24, 0xe0, 0x6d) #define EFI_RT_PROPERTIES_TABLE_GUID EFI_GUID(0xeb66918a, 0x7eef, 0x402a, 0x84, 0x2e, 0x93, 0x1d, 0x21, 0xc3, 0x8a, 0xe9) -- 2.25.1
