[U-Boot] [PATCH 06/14] efi_loader: Add runtime services

Leif Lindholm
2016-01-21T17:20:18Z

On Fri, Jan 15, 2016 at 06:06:12AM +0100, Alexander Graf wrote:
> After booting has finished, EFI allows firmware to still interact with the OS
> using the "runtime services". These callbacks live in a separate address space,
> since they are available long after U-Boot has been overwritten by the OS.
>
> This patch adds enough framework for arbitrary code inside of U-Boot to become
> a runtime service with the right section attributes set. For now, we don't make
> use of it yet though.
>
> We could maybe in the future map U-boot environment variables to EFI variables
> here.
>
> Signed-off-by: Alexander Graf <agraf@suse.de>

Just a couple of return value issues:

> ---
>
> v1 -> v2:
>
> - Fix runtime service sections
> - Add runtime detach
> - Enable runtime relocations
> - Add get_time
> - Fix relocation
> - Fix 32bit
> - Add am335x support
> - Move section definition to header
> - Add systab to runtime section
> - Add self-relocation hook table
> - Fix self-relocation
> - Relocate efi_runtime section early during bootup
> - Fix return values for a number of callbacks to be more UEFI compliant
> - Move to GPLv2+
> ---
> arch/arm/config.mk | 4 +
> arch/arm/cpu/armv8/u-boot.lds | 16 +++
> arch/arm/cpu/u-boot.lds | 30 +++++
> arch/arm/lib/sections.c | 4 +
> board/ti/am335x/u-boot.lds | 30 +++++
> common/board_r.c | 4 +
> include/efi_loader.h | 10 ++
> lib/efi_loader/efi_boottime.c | 6 +-
> lib/efi_loader/efi_runtime.c | 300 ++++++++++++++++++++++++++++++++++++++++++
> 9 files changed, 401 insertions(+), 3 deletions(-)
> create mode 100644 lib/efi_loader/efi_runtime.c
>

...

> diff --git a/lib/efi_loader/efi_runtime.c b/lib/efi_loader/efi_runtime.c
> new file mode 100644
> index 0000000..b7aa1e9
> --- /dev/null
> +++ b/lib/efi_loader/efi_runtime.c
> @@ -0,0 +1,300 @@
> +/*
> + * EFI application runtime services
> + *
> + * Copyright (c) 2016 Alexander Graf
> + *
> + * SPDX-License-Identifier: GPL-2.0+
> + */
> +
> +#include <common.h>
> +#include <efi_loader.h>
> +#include <command.h>
> +#include <asm/global_data.h>
> +#include <rtc.h>
> +
> +/* For manual relocation support */
> +DECLARE_GLOBAL_DATA_PTR;
> +
> +static efi_status_t EFI_RUNTIME_TEXT efi_unimplemented(void);
> +static efi_status_t EFI_RUNTIME_TEXT efi_device_error(void);
> +static efi_status_t EFI_RUNTIME_TEXT efi_invalid_parameter(void);
> +
> +#if defined(CONFIG_ARM64)
> +#define R_RELATIVE 1027
> +#define R_MASK 0xffffffffULL
> +#define IS_RELA 1
> +#elif defined(CONFIG_ARM)
> +#define R_RELATIVE 23
> +#define R_MASK 0xffULL
> +#else
> +#error Need to add relocation awareness
> +#endif
> +
> +struct elf_rel {
> + ulong *offset;
> + ulong info;
> +};
> +
> +struct elf_rela {
> + ulong *offset;
> + ulong info;
> + long addend;
> +};
> +
> +/*
> + * EFI Runtime code lives in 2 stages. In the first stage, U-Boot and an EFI
> + * payload are running concurrently at the same time. In this mode, we can
> + * handle a good number of runtime callbacks
> + */
> +
> +static void efi_reset_system(enum efi_reset_type reset_type,
> + efi_status_t reset_status, unsigned long data_size,
> + void *reset_data)
> +{
> + EFI_ENTRY("%d %lx %lx %p", reset_type, reset_status, data_size, reset_data);
> +
> + switch (reset_type) {
> + case EFI_RESET_COLD:
> + case EFI_RESET_WARM:
> + do_reset(NULL, 0, 0, NULL);
> + break;
> + case EFI_RESET_SHUTDOWN:
> + /* We don't have anything to map this to */
> + break;
> + }
> +
> + EFI_EXIT(EFI_SUCCESS);
> +}
> +
> +static efi_status_t efi_get_time(struct efi_time *time,
> + struct efi_time_cap *capabilities)
> +{
> +#ifdef CONFIG_CMD_DATE
> +
> + struct rtc_time tm;
> + int r;
> +#ifdef CONFIG_DM_RTC
> + struct udevice *dev;
> +#endif
> +
> + EFI_ENTRY("%p %p", time, capabilities);
> +
> +#ifdef CONFIG_DM_RTC
> + r = uclass_get_device(UCLASS_RTC, 0, &dev);
> + if (r)
> + return EFI_EXIT(EFI_UNSUPPORTED);

EFI_DEVICE_ERROR?

> +#endif
> +
> +#ifdef CONFIG_DM_RTC
> + r = dm_rtc_get(dev, &tm);
> +#else
> + r = rtc_get(&tm);
> +#endif
> + if (r)
> + return EFI_EXIT(EFI_UNSUPPORTED);

EFI_DEVICE_ERROR?

> +
> + memset(time, 0, sizeof(*time));
> + time->year = tm.tm_year;
> + time->month = tm.tm_mon;
> + time->day = tm.tm_mday;
> + time->hour = tm.tm_hour;
> + time->minute = tm.tm_min;
> + time->daylight = tm.tm_isdst;
> +
> + return EFI_EXIT(EFI_SUCCESS);
> +
> +#else /* CONFIG_CMD_DATE */
> +
> + return EFI_DEVICE_ERROR;
> +
> +#endif /* CONFIG_CMD_DATE */
> +}