Subject: [RFC PATCH v2 1/1] arm64: Add boot time configuration of Intermediate Physical Address size

From: [email-masked] (Catalin Marinas)
Date: Wed, 12 Mar 2014 16:54:12 +0000

On Tue, Mar 11, 2014 at 10:11:20AM +0000, Radha Mohan wrote:
> Any more comments?

It looks fine to me but I'd like an ack from Marc as well on the KVM
bits.

Patch below for reference. Thanks.

> On Fri, Mar 7, 2014 at 2:19 PM,  <[email-masked]> wrote:
> > From: Radha Mohan Chintakuntla <[email-masked]>
> >
> > ARMv8 supports a range of physical address bit sizes. The PARange bits
> > from ID_AA64MMFR0_EL1 register are read during boot-time and the
> > intermediate physical address size bits are written in the translation
> > control registers (TCR_EL1 and VTCR_EL2).
> >
> > There is no change in the VA bits and levels of translation.
> >
> > Signed-off-by: Radha Mohan Chintakuntla <[email-masked]>
> > ---
> >  arch/arm64/include/asm/kvm_arm.h       |   15 ++++++---------
> >  arch/arm64/include/asm/pgtable-hwdef.h |    5 ++---
> >  arch/arm64/kvm/hyp-init.S              |    6 ++++++
> >  arch/arm64/mm/proc.S                   |    8 +++++++-
> >  4 files changed, 21 insertions(+), 13 deletions(-)
> >
> > diff --git a/arch/arm64/include/asm/kvm_arm.h b/arch/arm64/include/asm/kvm_arm.h
> > index 0eb3986..21ef48d 100644
> > --- a/arch/arm64/include/asm/kvm_arm.h
> > +++ b/arch/arm64/include/asm/kvm_arm.h
> > @@ -106,7 +106,6 @@
> >
> >  /* VTCR_EL2 Registers bits */
> >  #define VTCR_EL2_PS_MASK       (7 << 16)
> > -#define VTCR_EL2_PS_40B                (2 << 16)
> >  #define VTCR_EL2_TG0_MASK      (1 << 14)
> >  #define VTCR_EL2_TG0_4K                (0 << 14)
> >  #define VTCR_EL2_TG0_64K       (1 << 14)
> > @@ -129,10 +128,9 @@
> >   * 64kB pages (TG0 = 1)
> >   * 2 level page tables (SL = 1)
> >   */
> > -#define VTCR_EL2_FLAGS         (VTCR_EL2_PS_40B | VTCR_EL2_TG0_64K | \
> > -                                VTCR_EL2_SH0_INNER | VTCR_EL2_ORGN0_WBWA | \
> > -                                VTCR_EL2_IRGN0_WBWA | VTCR_EL2_SL0_LVL1 | \
> > -                                VTCR_EL2_T0SZ_40B)
> > +#define VTCR_EL2_FLAGS         (VTCR_EL2_TG0_64K | VTCR_EL2_SH0_INNER | \
> > +                                VTCR_EL2_ORGN0_WBWA | VTCR_EL2_IRGN0_WBWA | \
> > +                                VTCR_EL2_SL0_LVL1 | VTCR_EL2_T0SZ_40B)
> >  #define VTTBR_X                (38 - VTCR_EL2_T0SZ_40B)
> >  #else
> >  /*
> > @@ -142,10 +140,9 @@
> >   * 4kB pages (TG0 = 0)
> >   * 3 level page tables (SL = 1)
> >   */
> > -#define VTCR_EL2_FLAGS         (VTCR_EL2_PS_40B | VTCR_EL2_TG0_4K | \
> > -                                VTCR_EL2_SH0_INNER | VTCR_EL2_ORGN0_WBWA | \
> > -                                VTCR_EL2_IRGN0_WBWA | VTCR_EL2_SL0_LVL1 | \
> > -                                VTCR_EL2_T0SZ_40B)
> > +#define VTCR_EL2_FLAGS         (VTCR_EL2_TG0_4K | VTCR_EL2_SH0_INNER | \
> > +                                VTCR_EL2_ORGN0_WBWA | VTCR_EL2_IRGN0_WBWA | \
> > +                                VTCR_EL2_SL0_LVL1 | VTCR_EL2_T0SZ_40B)
> >  #define VTTBR_X                (37 - VTCR_EL2_T0SZ_40B)
> >  #endif
> >
> > diff --git a/arch/arm64/include/asm/pgtable-hwdef.h b/arch/arm64/include/asm/pgtable-hwdef.h
> > index b1d2e26..f7af66b 100644
> > --- a/arch/arm64/include/asm/pgtable-hwdef.h
> > +++ b/arch/arm64/include/asm/pgtable-hwdef.h
> > @@ -100,9 +100,9 @@
> >  #define PTE_HYP                        PTE_USER
> >
> >  /*
> > - * 40-bit physical address supported.
> > + * Highest possible physical address supported.
> >   */
> > -#define PHYS_MASK_SHIFT                (40)
> > +#define PHYS_MASK_SHIFT                (48)
> >  #define PHYS_MASK              ((UL(1) << PHYS_MASK_SHIFT) - 1)
> >
> >  /*
> > @@ -122,7 +122,6 @@
> >  #define TCR_SHARED             ((UL(3) << 12) | (UL(3) << 28))
> >  #define TCR_TG0_64K            (UL(1) << 14)
> >  #define TCR_TG1_64K            (UL(1) << 30)
> > -#define TCR_IPS_40BIT          (UL(2) << 32)
> >  #define TCR_ASID16             (UL(1) << 36)
> >  #define TCR_TBI0               (UL(1) << 37)
> >
> > diff --git a/arch/arm64/kvm/hyp-init.S b/arch/arm64/kvm/hyp-init.S
> > index 2b0244d..d968796 100644
> > --- a/arch/arm64/kvm/hyp-init.S
> > +++ b/arch/arm64/kvm/hyp-init.S
> > @@ -68,6 +68,12 @@ __do_hyp_init:
> >         msr     tcr_el2, x4
> >
> >         ldr     x4, =VTCR_EL2_FLAGS
> > +       /*
> > +        * Read the PARange bits from ID_AA64MMFR0_EL1 and set the PS bits in
> > +        * VTCR_EL2.
> > +        */
> > +       mrs     x5, ID_AA64MMFR0_EL1
> > +       bfi     x4, x5, #16, #3
> >         msr     vtcr_el2, x4
> >
> >         mrs     x4, mair_el1
> > diff --git a/arch/arm64/mm/proc.S b/arch/arm64/mm/proc.S
> > index e0ef63c..e085ee6 100644
> > --- a/arch/arm64/mm/proc.S
> > +++ b/arch/arm64/mm/proc.S
> > @@ -209,8 +209,14 @@ ENTRY(__cpu_setup)
> >          * Set/prepare TCR and TTBR. We use 512GB (39-bit) address range for
> >          * both user and kernel.
> >          */
> > -       ldr     x10, =TCR_TxSZ(VA_BITS) | TCR_FLAGS | TCR_IPS_40BIT | \
> > +       ldr     x10, =TCR_TxSZ(VA_BITS) | TCR_FLAGS | \
> >                       TCR_ASID16 | TCR_TBI0 | (1 << 31)
> > +       /*
> > +        * Read the PARange bits from ID_AA64MMFR0_EL1 and set the IPS bits in
> > +        * TCR_EL1.
> > +        */
> > +       mrs     x9, ID_AA64MMFR0_EL1
> > +       bfi     x10, x9, #32, #3
> >  #ifdef CONFIG_ARM64_64K_PAGES
> >         orr     x10, x10, TCR_TG0_64K
> >         orr     x10, x10, TCR_TG1_64K
> > --
> > 1.7.1