Commit 811595a2 authored by Peter Maydell's avatar Peter Maydell
Browse files

target-arm: Fix reset and migration of TTBCR(S) 



Commit 6459b94c broke reset and migration of the AArch32
TTBCR(S) register if the guest used non-LPAE page tables. This is
because the AArch32 TTBCR register definition is marked as ARM_CP_ALIAS,
meaning that the AArch64 variant has to handle migration and reset.
Although AArch64 TCR_EL3 doesn't need to care about the mask and
base_mask fields, AArch32 may do so, and so we must use the special
TTBCR reset and raw write functions to ensure they are set correctly.

This doesn't affect TCR_EL2, because the AArch32 equivalent of that
is HTCR, which never uses the non-LPAE page table variant.

Signed-off-by: default avatarPeter Maydell <peter.maydell@linaro.org>
Reported-by: default avatarPranith Kumar <bobby.prani+qemu@gmail.com>
Reviewed-by: default avatarSergey Fedorov <sergey.fedorov@linaro.org>
Message-id: 1465488181-31977-1-git-send-email-peter.maydell@linaro.org
parent 8433dee0

target-arm/helper.c

+4 −1
Original line number Diff line number Diff line
@@ -3765,8 +3765,11 @@ static const ARMCPRegInfo el3_cp_reginfo[] = { 
      .opc0 = 3, .opc1 = 6, .crn = 2, .crm = 0, .opc2 = 2,

      .access = PL3_RW,

      /* no .writefn needed as this can't cause an ASID change;

       * no .raw_writefn or .resetfn needed as we never use mask/base_mask

       * we must provide a .raw_writefn and .resetfn because we handle

       * reset and migration for the AArch32 TTBCR(S), which might be

       * using mask and base_mask.

       */

      .resetfn = vmsa_ttbcr_reset, .raw_writefn = vmsa_ttbcr_raw_write,

      .fieldoffset = offsetof(CPUARMState, cp15.tcr_el[3]) },

    { .name = "ELR_EL3", .state = ARM_CP_STATE_AA64,

      .type = ARM_CP_ALIAS,