[U-Boot] [PATCH v8 1/3] armv8: Support loading 32-bit OS in AArch32 execution state

Ryan Harkin ryan.harkin at linaro.org
Wed Jan 11 09:59:02 CET 2017


Hi Alison,

I wasn't sure where about in this thread to reply to this patch, so I
thought here was as good as any...

I know I tested this commit and it works for me. However, my colleague
Tixy has spotted a recent warning on the kernel dmesg output that only
arrived with an update to u-boot:

[    0.000000] WARNING: x1-x3 nonzero in violation of boot protocol:
[    0.000000]     x1: 0000000000000000
[    0.000000]     x2: 0000000000000000
[    0.000000]     x3: 0000000080080000
[    0.000000] This indicates a broken bootloader or old kernel

This happens on our ARM64 kernels, both the 4.4 based kernel and the
4.9.0 based kernel. They boot, it's with the extra warning.

I bisected it down to the change in this email thread, upstream as
commit ec6617c39741adc6c54952564579e32c3c09c66f in the master repo.

And I can see below in many places that the code is using x3 for the
first time. I'm not sure which one is causing the warning in the
kernel, but I guess we need to reset x3 to zero before jumping to the
kernel?

I'm happy to test any fixes if you wish to send them to me.

Thanks,
Ryan.



On 10 November 2016 at 02:49, Alison Wang <b18965 at freescale.com> wrote:
> To support loading a 32-bit OS, the execution state will change from
> AArch64 to AArch32 when jumping to kernel.
>
> The architecture information will be got through checking FIT image,
> then U-Boot will load 32-bit OS or 64-bit OS automatically.
>
> Signed-off-by: Ebony Zhu <ebony.zhu at nxp.com>
> Signed-off-by: Alison Wang <alison.wang at nxp.com>
> Signed-off-by: Chenhui Zhao <chenhui.zhao at nxp.com>
> ---
> Changes in v8:
> - Fix the issue when U-Boot is running in EL2 or EL1.
>
> Changes in v7:
> - Move the call for armv8_switch_to_el2_m into this patch.
>
> Changes in v6:
> - Modified armv8_switch_to_el1(). It will always jump to ep when switching to AArch64 or AArch32 modes.
> - Make other platforms compatible with the new armv8_switch_to_el2() and armv8_switch_to_el1().
>
> Changes in v5:
> - Modified armv8_switch_to_el2(). It will always jump to ep when switching to AArch64 or AArch32 modes.
>
> Changes in v4:
> - Correct config ARM64_SUPPORT_AARCH32.
> - Omit arch and ftaddr arguments.
> - Rename "xreg5" to "tmp".
> - Use xxx_RES1 to combine all RES1 fields in xxx register.
> - Use an immediate cmp directly.
> - Use #ifdef for CONFIG_ARM64_SUPPORT_AARCH32.
>
> Changes in v3:
> - Comments the functions and the arguments.
> - Rename the real parameters.
> - Use the macros instead of the magic values.
> - Remove the redundant codes.
> - Clean up all of the mess in boot_jump_linux().
> - Add CONFIG_ARM64_SUPPORT_AARCH32 to detect for some ARM64 system doesn't support AArch32 state.
>
> Changes in v2:
> - armv8_switch_to_el2_aarch32() is removed. armv8_switch_to_el2_m is used
>   to switch to AArch64 EL2 or AArch32 Hyp.
> - armv8_switch_to_el1_aarch32() is removed. armv8_switch_to_el1_m is used
>   to switch to AArch64 EL1 or AArch32 SVC.
>
>  arch/arm/Kconfig                              |   6 +
>  arch/arm/cpu/armv8/fsl-layerscape/lowlevel.S  |  61 +++++++--
>  arch/arm/cpu/armv8/start.S                    |   8 ++
>  arch/arm/cpu/armv8/transition.S               |  23 +++-
>  arch/arm/include/asm/arch-fsl-layerscape/mp.h |   4 +
>  arch/arm/include/asm/macro.h                  | 176 +++++++++++++++++++-------
>  arch/arm/include/asm/system.h                 | 119 ++++++++++++++++-
>  arch/arm/lib/bootm.c                          |  39 +++++-
>  arch/arm/mach-rmobile/lowlevel_init_gen3.S    |   9 +-
>  common/image-fit.c                            |  19 ++-
>  10 files changed, 396 insertions(+), 68 deletions(-)
>
> diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
> index d7a9b11..18c23c0 100644
> --- a/arch/arm/Kconfig
> +++ b/arch/arm/Kconfig
> @@ -126,6 +126,12 @@ config ENABLE_ARM_SOC_BOOT0_HOOK
>           ARM_SOC_BOOT0_HOOK which contains the required assembler
>           preprocessor code.
>
> +config ARM64_SUPPORT_AARCH32
> +       bool "ARM64 system support AArch32 execution state"
> +       default y if ARM64 && !TARGET_THUNDERX_88XX
> +       help
> +         This ARM64 system supports AArch32 execution state.
> +
>  choice
>         prompt "Target select"
>         default TARGET_HIKEY
> diff --git a/arch/arm/cpu/armv8/fsl-layerscape/lowlevel.S b/arch/arm/cpu/armv8/fsl-layerscape/lowlevel.S
> index 5700b1f..8e6ad4b 100644
> --- a/arch/arm/cpu/armv8/fsl-layerscape/lowlevel.S
> +++ b/arch/arm/cpu/armv8/fsl-layerscape/lowlevel.S
> @@ -13,6 +13,7 @@
>  #ifdef CONFIG_MP
>  #include <asm/arch/mp.h>
>  #endif
> +#include <asm/u-boot.h>
>
>  ENTRY(lowlevel_init)
>         mov     x29, lr                 /* Save LR */
> @@ -339,11 +340,6 @@ ENTRY(secondary_boot_func)
>          gic_wait_for_interrupt_m x0, w1
>  #endif
>
> -       bl secondary_switch_to_el2
> -#ifdef CONFIG_ARMV8_SWITCH_TO_EL1
> -       bl secondary_switch_to_el1
> -#endif
> -
>  slave_cpu:
>         wfe
>         ldr     x0, [x11]
> @@ -356,19 +352,64 @@ slave_cpu:
>         tbz     x1, #25, cpu_is_le
>         rev     x0, x0                  /* BE to LE conversion */
>  cpu_is_le:
> -       br      x0                      /* branch to the given address */
> +       ldr     x5, [x11, #24]
> +       ldr     x6, =IH_ARCH_DEFAULT
> +       cmp     x6, x5
> +       b.eq    1f
> +
> +#ifdef CONFIG_ARMV8_SWITCH_TO_EL1
> +       adr     x3, secondary_switch_to_el1
> +       ldr     x4, =ES_TO_AARCH64
> +#else
> +       ldr     x3, [x11]
> +       ldr     x4, =ES_TO_AARCH32
> +#endif
> +       bl      secondary_switch_to_el2
> +
> +1:
> +#ifdef CONFIG_ARMV8_SWITCH_TO_EL1
> +       adr     x3, secondary_switch_to_el1
> +#else
> +       ldr     x3, [x11]
> +#endif
> +       ldr     x4, =ES_TO_AARCH64
> +       bl      secondary_switch_to_el2
> +
>  ENDPROC(secondary_boot_func)
>
>  ENTRY(secondary_switch_to_el2)
> -       switch_el x0, 1f, 0f, 0f
> +       switch_el x5, 1f, 0f, 0f
>  0:     ret
> -1:     armv8_switch_to_el2_m x0
> +1:     armv8_switch_to_el2_m x3, x4, x5
>  ENDPROC(secondary_switch_to_el2)
>
>  ENTRY(secondary_switch_to_el1)
> -       switch_el x0, 0f, 1f, 0f
> +       mrs     x0, mpidr_el1
> +       ubfm    x1, x0, #8, #15
> +       ubfm    x2, x0, #0, #1
> +       orr     x10, x2, x1, lsl #2     /* x10 has LPID */
> +
> +       lsl     x1, x10, #6
> +       ldr     x0, =__spin_table
> +       /* physical address of this cpus spin table element */
> +       add     x11, x1, x0
> +
> +       ldr     x3, [x11]
> +
> +       ldr     x5, [x11, #24]
> +       ldr     x6, =IH_ARCH_DEFAULT
> +       cmp     x6, x5
> +       b.eq    2f
> +
> +       ldr     x4, =ES_TO_AARCH32
> +       bl      switch_to_el1
> +
> +2:     ldr     x4, =ES_TO_AARCH64
> +
> +switch_to_el1:
> +       switch_el x5, 0f, 1f, 0f
>  0:     ret
> -1:     armv8_switch_to_el1_m x0, x1
> +1:     armv8_switch_to_el1_m x3, x4, x5
>  ENDPROC(secondary_switch_to_el1)
>
>         /* Ensure that the literals used by the secondary boot code are
> diff --git a/arch/arm/cpu/armv8/start.S b/arch/arm/cpu/armv8/start.S
> index 19c771d..4f5f6d8 100644
> --- a/arch/arm/cpu/armv8/start.S
> +++ b/arch/arm/cpu/armv8/start.S
> @@ -251,9 +251,17 @@ WEAK(lowlevel_init)
>         /*
>          * All slaves will enter EL2 and optionally EL1.
>          */
> +       adr     x3, lowlevel_in_el2
> +       ldr     x4, =ES_TO_AARCH64
>         bl      armv8_switch_to_el2
> +
> +lowlevel_in_el2:
>  #ifdef CONFIG_ARMV8_SWITCH_TO_EL1
> +       adr     x3, lowlevel_in_el1
> +       ldr     x4, =ES_TO_AARCH64
>         bl      armv8_switch_to_el1
> +
> +lowlevel_in_el1:
>  #endif
>
>  #endif /* CONFIG_ARMV8_MULTIENTRY */
> diff --git a/arch/arm/cpu/armv8/transition.S b/arch/arm/cpu/armv8/transition.S
> index 253a39b..bbccf2b 100644
> --- a/arch/arm/cpu/armv8/transition.S
> +++ b/arch/arm/cpu/armv8/transition.S
> @@ -11,13 +11,24 @@
>  #include <asm/macro.h>
>
>  ENTRY(armv8_switch_to_el2)
> -       switch_el x0, 1f, 0f, 0f
> -0:     ret
> -1:     armv8_switch_to_el2_m x0
> +       switch_el x5, 1f, 0f, 0f
> +0:
> +       /*
> +        * x3 is kernel entry point or switch_to_el1
> +        * if CONFIG_ARMV8_SWITCH_TO_EL1 is defined.
> +         * When running in EL2 now, jump to the
> +        * address saved in x3.
> +        */
> +       br x3
> +1:     armv8_switch_to_el2_m x3, x4, x5
>  ENDPROC(armv8_switch_to_el2)
>
>  ENTRY(armv8_switch_to_el1)
> -       switch_el x0, 0f, 1f, 0f
> -0:     ret
> -1:     armv8_switch_to_el1_m x0, x1
> +       switch_el x5, 0f, 1f, 0f
> +0:
> +       /* x3 is kernel entry point. When running in EL1
> +        * now, jump to the address saved in x3.
> +        */
> +       br x3
> +1:     armv8_switch_to_el1_m x3, x4, x5
>  ENDPROC(armv8_switch_to_el1)
> diff --git a/arch/arm/include/asm/arch-fsl-layerscape/mp.h b/arch/arm/include/asm/arch-fsl-layerscape/mp.h
> index f7306ff..ebf84b6 100644
> --- a/arch/arm/include/asm/arch-fsl-layerscape/mp.h
> +++ b/arch/arm/include/asm/arch-fsl-layerscape/mp.h
> @@ -36,4 +36,8 @@ void secondary_boot_func(void);
>  int is_core_online(u64 cpu_id);
>  u32 cpu_pos_mask(void);
>  #endif
> +
> +#define IH_ARCH_ARM            2       /* ARM */
> +#define IH_ARCH_ARM64          22      /* ARM64 */
> +
>  #endif /* _FSL_LAYERSCAPE_MP_H */
> diff --git a/arch/arm/include/asm/macro.h b/arch/arm/include/asm/macro.h
> index 9bb0efa..2553e3e 100644
> --- a/arch/arm/include/asm/macro.h
> +++ b/arch/arm/include/asm/macro.h
> @@ -8,6 +8,11 @@
>
>  #ifndef __ASM_ARM_MACRO_H__
>  #define __ASM_ARM_MACRO_H__
> +
> +#ifdef CONFIG_ARM64
> +#include <asm/system.h>
> +#endif
> +
>  #ifdef __ASSEMBLY__
>
>  /*
> @@ -135,13 +140,21 @@ lr        .req    x30
>  #endif
>  .endm
>
> -.macro armv8_switch_to_el2_m, xreg1
> -       /* 64bit EL2 | HCE | SMD | RES1 (Bits[5:4]) | Non-secure EL0/EL1 */
> -       mov     \xreg1, #0x5b1
> -       msr     scr_el3, \xreg1
> +/*
> + * Switch from EL3 to EL2 for ARMv8
> + * @ep:     kernel entry point
> + * @flag:   The execution state flag for lower exception
> + *          level, ES_TO_AARCH64 or ES_TO_AARCH32
> + * @tmp:    temporary register
> + *
> + * For loading 32-bit OS, x1 is machine nr and x2 is ftaddr.
> + * For loading 64-bit OS, x0 is physical address to the FDT blob.
> + * They will be passed to the guest.
> + */
> +.macro armv8_switch_to_el2_m, ep, flag, tmp
>         msr     cptr_el3, xzr           /* Disable coprocessor traps to EL3 */
> -       mov     \xreg1, #0x33ff
> -       msr     cptr_el2, \xreg1        /* Disable coprocessor traps to EL2 */
> +       mov     \tmp, #CPTR_EL2_RES1
> +       msr     cptr_el2, \tmp          /* Disable coprocessor traps to EL2 */
>
>         /* Initialize Generic Timers */
>         msr     cntvoff_el2, xzr
> @@ -152,45 +165,90 @@ lr        .req    x30
>          * and RES0 bits (31,30,27,26,24,21,20,17,15-13,10-6) +
>          * EE,WXN,I,SA,C,A,M to 0
>          */
> -       mov     \xreg1, #0x0830
> -       movk    \xreg1, #0x30C5, lsl #16
> -       msr     sctlr_el2, \xreg1
> +       ldr     \tmp, =(SCTLR_EL2_RES1 | SCTLR_EL2_EE_LE |\
> +                       SCTLR_EL2_WXN_DIS | SCTLR_EL2_ICACHE_DIS |\
> +                       SCTLR_EL2_SA_DIS | SCTLR_EL2_DCACHE_DIS |\
> +                       SCTLR_EL2_ALIGN_DIS | SCTLR_EL2_MMU_DIS)
> +       msr     sctlr_el2, \tmp
> +
> +       mov     \tmp, sp
> +       msr     sp_el2, \tmp            /* Migrate SP */
> +       mrs     \tmp, vbar_el3
> +       msr     vbar_el2, \tmp          /* Migrate VBAR */
> +
> +       /* Check switch to AArch64 EL2 or AArch32 Hypervisor mode */
> +       cmp     \flag, #ES_TO_AARCH32
> +       b.eq    1f
> +
> +       /*
> +        * The next lower exception level is AArch64, 64bit EL2 | HCE |
> +        * SMD | RES1 (Bits[5:4]) | Non-secure EL0/EL1.
> +        */
> +       ldr     \tmp, =(SCR_EL3_RW_AARCH64 | SCR_EL3_HCE_EN |\
> +                       SCR_EL3_SMD_DIS | SCR_EL3_RES1 |\
> +                       SCR_EL3_NS_EN)
> +       msr     scr_el3, \tmp
>
>         /* Return to the EL2_SP2 mode from EL3 */
> -       mov     \xreg1, sp
> -       msr     sp_el2, \xreg1          /* Migrate SP */
> -       mrs     \xreg1, vbar_el3
> -       msr     vbar_el2, \xreg1        /* Migrate VBAR */
> -       mov     \xreg1, #0x3c9
> -       msr     spsr_el3, \xreg1        /* EL2_SP2 | D | A | I | F */
> -       msr     elr_el3, lr
> +       ldr     \tmp, =(SPSR_EL_DEBUG_MASK | SPSR_EL_SERR_MASK |\
> +                       SPSR_EL_IRQ_MASK | SPSR_EL_FIQ_MASK |\
> +                       SPSR_EL_M_AARCH64 | SPSR_EL_M_EL2H)
> +       msr     spsr_el3, \tmp
> +       msr     elr_el3, \ep
> +       eret
> +
> +1:
> +       /*
> +        * The next lower exception level is AArch32, 32bit EL2 | HCE |
> +        * SMD | RES1 (Bits[5:4]) | Non-secure EL0/EL1.
> +        */
> +       ldr     \tmp, =(SCR_EL3_RW_AARCH32 | SCR_EL3_HCE_EN |\
> +                       SCR_EL3_SMD_DIS | SCR_EL3_RES1 |\
> +                       SCR_EL3_NS_EN)
> +       msr     scr_el3, \tmp
> +
> +       /* Return to AArch32 Hypervisor mode */
> +       ldr     \tmp, =(SPSR_EL_END_LE | SPSR_EL_ASYN_MASK |\
> +                       SPSR_EL_IRQ_MASK | SPSR_EL_FIQ_MASK |\
> +                       SPSR_EL_T_A32 | SPSR_EL_M_AARCH32 |\
> +                       SPSR_EL_M_HYP)
> +       msr     spsr_el3, \tmp
> +       msr     elr_el3, \ep
>         eret
>  .endm
>
> -.macro armv8_switch_to_el1_m, xreg1, xreg2
> +/*
> + * Switch from EL2 to EL1 for ARMv8
> + * @ep:     kernel entry point
> + * @flag:   The execution state flag for lower exception
> + *          level, ES_TO_AARCH64 or ES_TO_AARCH32
> + * @tmp:    temporary register
> + *
> + * For loading 32-bit OS, x1 is machine nr and x2 is ftaddr.
> + * For loading 64-bit OS, x0 is physical address to the FDT blob.
> + * They will be passed to the guest.
> + */
> +.macro armv8_switch_to_el1_m, ep, flag, tmp
>         /* Initialize Generic Timers */
> -       mrs     \xreg1, cnthctl_el2
> -       orr     \xreg1, \xreg1, #0x3    /* Enable EL1 access to timers */
> -       msr     cnthctl_el2, \xreg1
> +       mrs     \tmp, cnthctl_el2
> +       /* Enable EL1 access to timers */
> +       orr     \tmp, \tmp, #(CNTHCTL_EL2_EL1PCEN_EN |\
> +               CNTHCTL_EL2_EL1PCTEN_EN)
> +       msr     cnthctl_el2, \tmp
>         msr     cntvoff_el2, xzr
>
>         /* Initilize MPID/MPIDR registers */
> -       mrs     \xreg1, midr_el1
> -       mrs     \xreg2, mpidr_el1
> -       msr     vpidr_el2, \xreg1
> -       msr     vmpidr_el2, \xreg2
> +       mrs     \tmp, midr_el1
> +       msr     vpidr_el2, \tmp
> +       mrs     \tmp, mpidr_el1
> +       msr     vmpidr_el2, \tmp
>
>         /* Disable coprocessor traps */
> -       mov     \xreg1, #0x33ff
> -       msr     cptr_el2, \xreg1        /* Disable coprocessor traps to EL2 */
> +       mov     \tmp, #CPTR_EL2_RES1
> +       msr     cptr_el2, \tmp          /* Disable coprocessor traps to EL2 */
>         msr     hstr_el2, xzr           /* Disable coprocessor traps to EL2 */
> -       mov     \xreg1, #3 << 20
> -       msr     cpacr_el1, \xreg1       /* Enable FP/SIMD at EL1 */
> -
> -       /* Initialize HCR_EL2 */
> -       mov     \xreg1, #(1 << 31)              /* 64bit EL1 */
> -       orr     \xreg1, \xreg1, #(1 << 29)      /* Disable HVC */
> -       msr     hcr_el2, \xreg1
> +       mov     \tmp, #CPACR_EL1_FPEN_EN
> +       msr     cpacr_el1, \tmp         /* Enable FP/SIMD at EL1 */
>
>         /* SCTLR_EL1 initialization
>          *
> @@ -199,18 +257,50 @@ lr        .req    x30
>          * UCI,EE,EOE,WXN,nTWE,nTWI,UCT,DZE,I,UMA,SED,ITD,
>          * CP15BEN,SA0,SA,C,A,M to 0
>          */
> -       mov     \xreg1, #0x0800
> -       movk    \xreg1, #0x30d0, lsl #16
> -       msr     sctlr_el1, \xreg1
> +       ldr     \tmp, =(SCTLR_EL1_RES1 | SCTLR_EL1_UCI_DIS |\
> +                       SCTLR_EL1_EE_LE | SCTLR_EL1_WXN_DIS |\
> +                       SCTLR_EL1_NTWE_DIS | SCTLR_EL1_NTWI_DIS |\
> +                       SCTLR_EL1_UCT_DIS | SCTLR_EL1_DZE_DIS |\
> +                       SCTLR_EL1_ICACHE_DIS | SCTLR_EL1_UMA_DIS |\
> +                       SCTLR_EL1_SED_EN | SCTLR_EL1_ITD_EN |\
> +                       SCTLR_EL1_CP15BEN_DIS | SCTLR_EL1_SA0_DIS |\
> +                       SCTLR_EL1_SA_DIS | SCTLR_EL1_DCACHE_DIS |\
> +                       SCTLR_EL1_ALIGN_DIS | SCTLR_EL1_MMU_DIS)
> +       msr     sctlr_el1, \tmp
> +
> +       mov     \tmp, sp
> +       msr     sp_el1, \tmp            /* Migrate SP */
> +       mrs     \tmp, vbar_el2
> +       msr     vbar_el1, \tmp          /* Migrate VBAR */
> +
> +       /* Check switch to AArch64 EL1 or AArch32 Supervisor mode */
> +       cmp     \flag, #ES_TO_AARCH32
> +       b.eq    1f
> +
> +       /* Initialize HCR_EL2 */
> +       ldr     \tmp, =(HCR_EL2_RW_AARCH64 | HCR_EL2_HCD_DIS)
> +       msr     hcr_el2, \tmp
>
>         /* Return to the EL1_SP1 mode from EL2 */
> -       mov     \xreg1, sp
> -       msr     sp_el1, \xreg1          /* Migrate SP */
> -       mrs     \xreg1, vbar_el2
> -       msr     vbar_el1, \xreg1        /* Migrate VBAR */
> -       mov     \xreg1, #0x3c5
> -       msr     spsr_el2, \xreg1        /* EL1_SP1 | D | A | I | F */
> -       msr     elr_el2, lr
> +       ldr     \tmp, =(SPSR_EL_DEBUG_MASK | SPSR_EL_SERR_MASK |\
> +                       SPSR_EL_IRQ_MASK | SPSR_EL_FIQ_MASK |\
> +                       SPSR_EL_M_AARCH64 | SPSR_EL_M_EL1H)
> +       msr     spsr_el2, \tmp
> +       msr     elr_el2, \ep
> +       eret
> +
> +1:
> +       /* Initialize HCR_EL2 */
> +       ldr     \tmp, =(HCR_EL2_RW_AARCH32 | HCR_EL2_HCD_DIS)
> +       msr     hcr_el2, \tmp
> +
> +       /* Return to AArch32 Supervisor mode from EL2 */
> +       ldr     \tmp, =(SPSR_EL_END_LE | SPSR_EL_ASYN_MASK |\
> +                       SPSR_EL_IRQ_MASK | SPSR_EL_FIQ_MASK |\
> +                       SPSR_EL_T_A32 | SPSR_EL_M_AARCH32 |\
> +                       SPSR_EL_M_SVC)
> +       msr     spsr_el2, \tmp
> +       msr     elr_el2, \ep
>         eret
>  .endm
>
> diff --git a/arch/arm/include/asm/system.h b/arch/arm/include/asm/system.h
> index c3c88d2..1c3f74d 100644
> --- a/arch/arm/include/asm/system.h
> +++ b/arch/arm/include/asm/system.h
> @@ -18,6 +18,95 @@
>  #define CR_WXN         (1 << 19)       /* Write Permision Imply XN     */
>  #define CR_EE          (1 << 25)       /* Exception (Big) Endian       */
>
> +#define ES_TO_AARCH64          1
> +#define ES_TO_AARCH32          0
> +
> +/*
> + * SCR_EL3 bits definitions
> + */
> +#define SCR_EL3_RW_AARCH64     (1 << 10) /* Next lower level is AArch64     */
> +#define SCR_EL3_RW_AARCH32     (0 << 10) /* Lower lowers level are AArch32  */
> +#define SCR_EL3_HCE_EN         (1 << 8)  /* Hypervisor Call enable          */
> +#define SCR_EL3_SMD_DIS                (1 << 7)  /* Secure Monitor Call disable     */
> +#define SCR_EL3_RES1           (3 << 4)  /* Reserved, RES1                  */
> +#define SCR_EL3_NS_EN          (1 << 0)  /* EL0 and EL1 in Non-scure state  */
> +
> +/*
> + * SPSR_EL3/SPSR_EL2 bits definitions
> + */
> +#define SPSR_EL_END_LE         (0 << 9)  /* Exception Little-endian          */
> +#define SPSR_EL_DEBUG_MASK     (1 << 9)  /* Debug exception masked           */
> +#define SPSR_EL_ASYN_MASK      (1 << 8)  /* Asynchronous data abort masked   */
> +#define SPSR_EL_SERR_MASK      (1 << 8)  /* System Error exception masked    */
> +#define SPSR_EL_IRQ_MASK       (1 << 7)  /* IRQ exception masked             */
> +#define SPSR_EL_FIQ_MASK       (1 << 6)  /* FIQ exception masked             */
> +#define SPSR_EL_T_A32          (0 << 5)  /* AArch32 instruction set A32      */
> +#define SPSR_EL_M_AARCH64      (0 << 4)  /* Exception taken from AArch64     */
> +#define SPSR_EL_M_AARCH32      (1 << 4)  /* Exception taken from AArch32     */
> +#define SPSR_EL_M_SVC          (0x3)     /* Exception taken from SVC mode    */
> +#define SPSR_EL_M_HYP          (0xa)     /* Exception taken from HYP mode    */
> +#define SPSR_EL_M_EL1H         (5)       /* Exception taken from EL1h mode   */
> +#define SPSR_EL_M_EL2H         (9)       /* Exception taken from EL2h mode   */
> +
> +/*
> + * CPTR_EL2 bits definitions
> + */
> +#define CPTR_EL2_RES1          (3 << 12 | 0x3ff)           /* Reserved, RES1 */
> +
> +/*
> + * SCTLR_EL2 bits definitions
> + */
> +#define SCTLR_EL2_RES1         (3 << 28 | 3 << 22 | 1 << 18 | 1 << 16 |\
> +                                1 << 11 | 3 << 4)          /* Reserved, RES1 */
> +#define SCTLR_EL2_EE_LE                (0 << 25) /* Exception Little-endian          */
> +#define SCTLR_EL2_WXN_DIS      (0 << 19) /* Write permission is not XN       */
> +#define SCTLR_EL2_ICACHE_DIS   (0 << 12) /* Instruction cache disabled       */
> +#define SCTLR_EL2_SA_DIS       (0 << 3)  /* Stack Alignment Check disabled   */
> +#define SCTLR_EL2_DCACHE_DIS   (0 << 2)  /* Data cache disabled              */
> +#define SCTLR_EL2_ALIGN_DIS    (0 << 1)  /* Alignment check disabled         */
> +#define SCTLR_EL2_MMU_DIS      (0)       /* MMU disabled                     */
> +
> +/*
> + * CNTHCTL_EL2 bits definitions
> + */
> +#define CNTHCTL_EL2_EL1PCEN_EN (1 << 1)  /* Physical timer regs accessible   */
> +#define CNTHCTL_EL2_EL1PCTEN_EN        (1 << 0)  /* Physical counter accessible      */
> +
> +/*
> + * HCR_EL2 bits definitions
> + */
> +#define HCR_EL2_RW_AARCH64     (1 << 31) /* EL1 is AArch64                   */
> +#define HCR_EL2_RW_AARCH32     (0 << 31) /* Lower levels are AArch32         */
> +#define HCR_EL2_HCD_DIS                (1 << 29) /* Hypervisor Call disabled         */
> +
> +/*
> + * CPACR_EL1 bits definitions
> + */
> +#define CPACR_EL1_FPEN_EN      (3 << 20) /* SIMD and FP instruction enabled  */
> +
> +/*
> + * SCTLR_EL1 bits definitions
> + */
> +#define SCTLR_EL1_RES1         (3 << 28 | 3 << 22 | 1 << 20 |\
> +                                1 << 11) /* Reserved, RES1                   */
> +#define SCTLR_EL1_UCI_DIS      (0 << 26) /* Cache instruction disabled       */
> +#define SCTLR_EL1_EE_LE                (0 << 25) /* Exception Little-endian          */
> +#define SCTLR_EL1_WXN_DIS      (0 << 19) /* Write permission is not XN       */
> +#define SCTLR_EL1_NTWE_DIS     (0 << 18) /* WFE instruction disabled         */
> +#define SCTLR_EL1_NTWI_DIS     (0 << 16) /* WFI instruction disabled         */
> +#define SCTLR_EL1_UCT_DIS      (0 << 15) /* CTR_EL0 access disabled          */
> +#define SCTLR_EL1_DZE_DIS      (0 << 14) /* DC ZVA instruction disabled      */
> +#define SCTLR_EL1_ICACHE_DIS   (0 << 12) /* Instruction cache disabled       */
> +#define SCTLR_EL1_UMA_DIS      (0 << 9)  /* User Mask Access disabled        */
> +#define SCTLR_EL1_SED_EN       (0 << 8)  /* SETEND instruction enabled       */
> +#define SCTLR_EL1_ITD_EN       (0 << 7)  /* IT instruction enabled           */
> +#define SCTLR_EL1_CP15BEN_DIS  (0 << 5)  /* CP15 barrier operation disabled  */
> +#define SCTLR_EL1_SA0_DIS      (0 << 4)  /* Stack Alignment EL0 disabled     */
> +#define SCTLR_EL1_SA_DIS       (0 << 3)  /* Stack Alignment EL1 disabled     */
> +#define SCTLR_EL1_DCACHE_DIS   (0 << 2)  /* Data cache disabled              */
> +#define SCTLR_EL1_ALIGN_DIS    (0 << 1)  /* Alignment check disabled         */
> +#define SCTLR_EL1_MMU_DIS      (0)       /* MMU disabled                     */
> +
>  #ifndef __ASSEMBLY__
>
>  u64 get_page_table_size(void);
> @@ -98,8 +187,34 @@ int __asm_flush_l3_dcache(void);
>  int __asm_invalidate_l3_icache(void);
>  void __asm_switch_ttbr(u64 new_ttbr);
>
> -void armv8_switch_to_el2(void);
> -void armv8_switch_to_el1(void);
> +/*
> + * Switch from EL3 to EL2 for ARMv8
> + *
> + * @args:        For loading 64-bit OS, fdt address.
> + *               For loading 32-bit OS, zero.
> + * @mach_nr:     For loading 64-bit OS, zero.
> + *               For loading 32-bit OS, machine nr
> + * @fdt_addr:    For loading 64-bit OS, zero.
> + *               For loading 32-bit OS, fdt address.
> + * @entry_point: kernel entry point
> + * @es_flag:     execution state flag, ES_TO_AARCH64 or ES_TO_AARCH32
> + */
> +void armv8_switch_to_el2(u64 args, u64 mach_nr, u64 fdt_addr,
> +                        u64 entry_point, u64 es_flag);
> +/*
> + * Switch from EL2 to EL1 for ARMv8
> + *
> + * @args:        For loading 64-bit OS, fdt address.
> + *               For loading 32-bit OS, zero.
> + * @mach_nr:     For loading 64-bit OS, zero.
> + *               For loading 32-bit OS, machine nr
> + * @fdt_addr:    For loading 64-bit OS, zero.
> + *               For loading 32-bit OS, fdt address.
> + * @entry_point: kernel entry point
> + * @es_flag:     execution state flag, ES_TO_AARCH64 or ES_TO_AARCH32
> + */
> +void armv8_switch_to_el1(u64 args, u64 mach_nr, u64 fdt_addr,
> +                        u64 entry_point, u64 es_flag);
>  void gic_init(void);
>  void gic_send_sgi(unsigned long sgino);
>  void wait_for_wakeup(void);
> diff --git a/arch/arm/lib/bootm.c b/arch/arm/lib/bootm.c
> index 53c3141..7015573 100644
> --- a/arch/arm/lib/bootm.c
> +++ b/arch/arm/lib/bootm.c
> @@ -193,10 +193,6 @@ static void do_nonsec_virt_switch(void)
>  {
>         smp_kick_all_cpus();
>         dcache_disable();       /* flush cache before swtiching to EL2 */
> -       armv8_switch_to_el2();
> -#ifdef CONFIG_ARMV8_SWITCH_TO_EL1
> -       armv8_switch_to_el1();
> -#endif
>  }
>  #endif
>
> @@ -273,6 +269,24 @@ bool armv7_boot_nonsec(void)
>  }
>  #endif
>
> +#ifdef CONFIG_ARM64
> +#ifdef CONFIG_ARMV8_SWITCH_TO_EL1
> +static void switch_to_el1(void)
> +{
> +       if ((IH_ARCH_DEFAULT == IH_ARCH_ARM64) &&
> +           (images.os.arch == IH_ARCH_ARM))
> +               armv8_switch_to_el1(0, (u64)gd->bd->bi_arch_number,
> +                                   (u64)images.ft_addr,
> +                                   (u64)images.ep,
> +                                   ES_TO_AARCH32);
> +       else
> +               armv8_switch_to_el1((u64)images.ft_addr, 0, 0,
> +                                   images.ep,
> +                                   ES_TO_AARCH64);
> +}
> +#endif
> +#endif
> +
>  /* Subcommand: GO */
>  static void boot_jump_linux(bootm_headers_t *images, int flag)
>  {
> @@ -292,7 +306,22 @@ static void boot_jump_linux(bootm_headers_t *images, int flag)
>
>         if (!fake) {
>                 do_nonsec_virt_switch();
> -               kernel_entry(images->ft_addr, NULL, NULL, NULL);
> +
> +#ifdef CONFIG_ARMV8_SWITCH_TO_EL1
> +               armv8_switch_to_el2((u64)images->ft_addr, 0, 0,
> +                                   (u64)switch_to_el1, ES_TO_AARCH64);
> +#else
> +               if ((IH_ARCH_DEFAULT == IH_ARCH_ARM64) &&
> +                   (images->os.arch == IH_ARCH_ARM))
> +                       armv8_switch_to_el2(0, (u64)gd->bd->bi_arch_number,
> +                                           (u64)images->ft_addr,
> +                                           (u64)images->ep,
> +                                           ES_TO_AARCH32);
> +               else
> +                       armv8_switch_to_el2((u64)images->ft_addr, 0, 0,
> +                                           images->ep,
> +                                           ES_TO_AARCH64);
> +#endif
>         }
>  #else
>         unsigned long machid = gd->bd->bi_arch_number;
> diff --git a/arch/arm/mach-rmobile/lowlevel_init_gen3.S b/arch/arm/mach-rmobile/lowlevel_init_gen3.S
> index 88ff56e..11acce0 100644
> --- a/arch/arm/mach-rmobile/lowlevel_init_gen3.S
> +++ b/arch/arm/mach-rmobile/lowlevel_init_gen3.S
> @@ -61,11 +61,18 @@ ENTRY(lowlevel_init)
>         /*
>          * All slaves will enter EL2 and optionally EL1.
>          */
> +       adr     x3, lowlevel_in_el2
> +       ldr     x4, =ES_TO_AARCH64
>         bl      armv8_switch_to_el2
> +
> +lowlevel_in_el2:
>  #ifdef CONFIG_ARMV8_SWITCH_TO_EL1
> +       adr     x3, lowlevel_in_el1
> +       ldr     x4, =ES_TO_AARCH64
>         bl      armv8_switch_to_el1
> -#endif
>
> +lowlevel_in_el1:
> +#endif
>  #endif /* CONFIG_ARMV8_MULTIENTRY */
>
>         bl      s_init
> diff --git a/common/image-fit.c b/common/image-fit.c
> index 77dc011..ea56d5b 100644
> --- a/common/image-fit.c
> +++ b/common/image-fit.c
> @@ -27,6 +27,7 @@ DECLARE_GLOBAL_DATA_PTR;
>  #include <u-boot/md5.h>
>  #include <u-boot/sha1.h>
>  #include <u-boot/sha256.h>
> +#include <generated/autoconf.h>
>
>  /*****************************************************************************/
>  /* New uImage format routines */
> @@ -1161,11 +1162,18 @@ int fit_image_check_os(const void *fit, int noffset, uint8_t os)
>  int fit_image_check_arch(const void *fit, int noffset, uint8_t arch)
>  {
>         uint8_t image_arch;
> +       int aarch32_support = 0;
> +
> +#ifdef CONFIG_ARM64_SUPPORT_AARCH32
> +       aarch32_support = 1;
> +#endif
>
>         if (fit_image_get_arch(fit, noffset, &image_arch))
>                 return 0;
>         return (arch == image_arch) ||
> -               (arch == IH_ARCH_I386 && image_arch == IH_ARCH_X86_64);
> +               (arch == IH_ARCH_I386 && image_arch == IH_ARCH_X86_64) ||
> +               (arch == IH_ARCH_ARM64 && image_arch == IH_ARCH_ARM &&
> +                aarch32_support);
>  }
>
>  /**
> @@ -1614,6 +1622,9 @@ int fit_image_load(bootm_headers_t *images, ulong addr,
>         int type_ok, os_ok;
>         ulong load, data, len;
>         uint8_t os;
> +#ifndef USE_HOSTCC
> +       uint8_t os_arch;
> +#endif
>         const char *prop_name;
>         int ret;
>
> @@ -1697,6 +1708,12 @@ int fit_image_load(bootm_headers_t *images, ulong addr,
>                 return -ENOEXEC;
>         }
>  #endif
> +
> +#ifndef USE_HOSTCC
> +       fit_image_get_arch(fit, noffset, &os_arch);
> +       images->os.arch = os_arch;
> +#endif
> +
>         if (image_type == IH_TYPE_FLATDT &&
>             !fit_image_check_comp(fit, noffset, IH_COMP_NONE)) {
>                 puts("FDT image is compressed");
> --
> 2.1.0.27.g96db324
>


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