[U-Boot] [PATCH v2 42/47] x86: Handle running as EFI payload

[Bin Meng]

On Fri, Jul 31, 2015 at 11:31 PM, Simon Glass <sjg at chromium.org> wrote:
> When U-Boot runs as an EFI payload it needs to avoid setting up the CPU
> again. Also U-Boot currently does not handle interrupts for many devices, so
> run with interrupts disabled.
>
> Signed-off-by: Simon Glass <sjg at chromium.org>
> ---
>
> Changes in v2:
> - Add a note that bootm does not work when running as an EFI app
> - Move EFI CAR settings to arch/x86/lib/efi/Kconfig
> - Rename CONFIG_ARCH_EFI to CONFIG_EFI_APP
>
>  arch/x86/Kconfig          |  6 ++++++
>  arch/x86/cpu/cpu.c        | 21 +++++++++++++--------
>  arch/x86/cpu/interrupts.c | 10 ++++++++--
>  arch/x86/lib/bootm.c      |  5 +++++
>  arch/x86/lib/efi/Kconfig  | 11 +++++++++++
>  5 files changed, 43 insertions(+), 10 deletions(-)
>  create mode 100644 arch/x86/lib/efi/Kconfig
>
> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> index f124d58..01ed760 100644
> --- a/arch/x86/Kconfig
> +++ b/arch/x86/Kconfig
> @@ -194,6 +194,7 @@ config X86_RAMTEST
>
>  config HAVE_FSP
>         bool "Add an Firmware Support Package binary"
> +       depends on !EFI
>         help
>           Select this option to add an Firmware Support Package binary to
>           the resulting U-Boot image. It is a binary blob which U-Boot uses
> @@ -309,6 +310,7 @@ menu "System tables"
>
>  config GENERATE_PIRQ_TABLE
>         bool "Generate a PIRQ table"
> +       depends on !EFI
>         default n
>         help
>           Generate a PIRQ routing table for this board. The PIRQ routing table
> @@ -319,6 +321,7 @@ config GENERATE_PIRQ_TABLE
>
>  config GENERATE_SFI_TABLE
>         bool "Generate a SFI (Simple Firmware Interface) table"
> +       depends on !EFI
>         help
>           The Simple Firmware Interface (SFI) provides a lightweight method
>           for platform firmware to pass information to the operating system
> @@ -333,6 +336,7 @@ config GENERATE_SFI_TABLE
>
>  config GENERATE_MP_TABLE
>         bool "Generate an MP (Multi-Processor) table"
> +       depends on !EFI
>         default n
>         help
>           Generate an MP (Multi-Processor) table for this board. The MP table
> @@ -383,4 +387,6 @@ config PCIE_ECAM_SIZE
>           so a default 0x10000000 size covers all of the 256 buses which is the
>           maximum number of PCI buses as defined by the PCI specification.
>
> +source "arch/x86/lib/efi/Kconfig"
> +
>  endmenu
> diff --git a/arch/x86/cpu/cpu.c b/arch/x86/cpu/cpu.c
> index d233a45..129777c 100644
> --- a/arch/x86/cpu/cpu.c
> +++ b/arch/x86/cpu/cpu.c
> @@ -330,13 +330,15 @@ int x86_cpu_init_f(void)
>         const u32 em_rst = ~X86_CR0_EM;
>         const u32 mp_ne_set = X86_CR0_MP | X86_CR0_NE;
>
> -       /* initialize FPU, reset EM, set MP and NE */
> -       asm ("fninit\n" \
> -            "movl %%cr0, %%eax\n" \
> -            "andl %0, %%eax\n" \
> -            "orl  %1, %%eax\n" \
> -            "movl %%eax, %%cr0\n" \
> -            : : "i" (em_rst), "i" (mp_ne_set) : "eax");
> +       if (ll_boot_init()) {
> +               /* initialize FPU, reset EM, set MP and NE */
> +               asm ("fninit\n" \
> +               "movl %%cr0, %%eax\n" \
> +               "andl %0, %%eax\n" \
> +               "orl  %1, %%eax\n" \
> +               "movl %%eax, %%cr0\n" \
> +               : : "i" (em_rst), "i" (mp_ne_set) : "eax");
> +       }
>
>         /* identify CPU via cpuid and store the decoded info into gd->arch */
>         if (has_cpuid()) {
> @@ -712,5 +714,8 @@ __weak int x86_init_cpus(void)
>
>  int cpu_init_r(void)
>  {
> -       return x86_init_cpus();
> +       if (ll_boot_init())
> +               return x86_init_cpus();
> +
> +       return 0;
>  }
> diff --git a/arch/x86/cpu/interrupts.c b/arch/x86/cpu/interrupts.c
> index a112938..9217307 100644
> --- a/arch/x86/cpu/interrupts.c
> +++ b/arch/x86/cpu/interrupts.c
> @@ -258,8 +258,14 @@ int interrupt_init(void)
>         /* Initialize core interrupt and exception functionality of CPU */
>         cpu_init_interrupts();
>
> -       /* It is now safe to enable interrupts */
> -       enable_interrupts();
> +       /*
> +        * It is now safe to enable interrupts.
> +        *
> +        * TODO(sjg at chromium.org): But we don't handle these correctly when
> +        * booted from EFI.
> +        */
> +       if (ll_boot_init())
> +               enable_interrupts();
>  #endif
>
>         return 0;
> diff --git a/arch/x86/lib/bootm.c b/arch/x86/lib/bootm.c
> index 445ee6e..f441c84 100644
> --- a/arch/x86/lib/bootm.c
> +++ b/arch/x86/lib/bootm.c
> @@ -164,7 +164,11 @@ int boot_linux_kernel(ulong setup_base, ulong load_address, bool image_64bit)
>                 * the data segments are 0x18, 4GB flat, and read/write.
>                 * U-boot is setting them up that way for itself in
>                 * arch/i386/cpu/cpu.c.
> +               *
> +               * Note that we cannot currently boot a kernel while running as
> +               * an EFI application. Please use the payload option for that.
>                 */
> +#ifndef CONFIG_EFI_APP
>                 __asm__ __volatile__ (
>                 "movl $0, %%ebp\n"
>                 "cli\n"
> @@ -173,6 +177,7 @@ int boot_linux_kernel(ulong setup_base, ulong load_address, bool image_64bit)
>                 [boot_params] "S"(setup_base),
>                 "b"(0), "D"(0)
>                 );
> +#endif
>         }
>
>         /* We can't get to here */
> diff --git a/arch/x86/lib/efi/Kconfig b/arch/x86/lib/efi/Kconfig
> new file mode 100644
> index 0000000..e0975d3
> --- /dev/null
> +++ b/arch/x86/lib/efi/Kconfig
> @@ -0,0 +1,11 @@
> +if EFI
> +
> +config SYS_CAR_ADDR
> +       hex
> +       default 0x100000
> +
> +config SYS_CAR_SIZE
> +       hex
> +       default 0x20000
> +
> +endif
> --

Reviewed-by: Bin Meng <bmeng.cn at gmail.com>