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

Alison Wang alison.wang at nxp.com
Thu Jan 12 06:55:56 CET 2017


Hi, Ryan,

	Thanks for your feedback. I will do some investigation and give you my solution.


Best Regards,
Alison Wang

> -----Original Message-----
> From: Ryan Harkin [mailto:ryan.harkin at linaro.org]
> Sent: Wednesday, January 11, 2017 4:59 PM
> To: Alison Wang <b18965 at freescale.com>
> Cc: york sun <york.sun at nxp.com>; Alexander Graf <agraf at suse.de>; Scott
> Wood <scott.wood at nxp.com>; Stuart Yoder <stuart.yoder at nxp.com>; Leo Li
> <leoyang.li at nxp.com>; David Feng <fenghua at phytium.com.cn>; Michal Simek
> <monstr at monstr.eu>; thomas.ab at samsung.com; mk7.kang at samsung.com; U-Boot
> ML <u-boot at lists.denx.de>; Alison Wang <alison.wang at nxp.com>; Jason Jin
> <jason.jin at nxp.com>; Jon Medhurst (Tixy) <tixy at linaro.org>
> Subject: Re: [PATCH v8 1/3] armv8: Support loading 32-bit OS in AArch32
> execution state
> 
> 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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