• Paul Burton's avatar
    MIPS: mm: Fix MIPS32 36b physical addressing (alchemy, netlogic) · 7b2cb64f
    Paul Burton authored
    There are 2 distinct cases in which a kernel for a MIPS32 CPU
    (CONFIG_CPU_MIPS32=y) may use 64 bit physical addresses
    (CONFIG_PHYS_ADDR_T_64BIT=y):
    
      - 36 bit physical addressing as used by RMI Alchemy & Netlogic XLP/XLR
        CPUs.
    
      - MIPS32r5 eXtended Physical Addressing (XPA).
    
    These 2 cases are distinct in that they require different behaviour from
    the kernel - the EntryLo registers have different formats. Until Linux
    v4.1 we only supported the first case, with code conditional upon the 2
    aforementioned Kconfig variables being set. Commit c5b36783 ("MIPS:
    Add support for XPA.") added support for the second case, but did so by
    modifying the code that existed for the first case rather than treating
    the 2 cases as distinct. Since the EntryLo registers have different
    formats this breaks the 36 bit Alchemy/XLP/XLR case. Fix this by
    splitting the 2 cases, with XPA cases now being conditional upon
    CONFIG_XPA and the non-XPA case matching the code as it existed prior to
    commit c5b36783 ("MIPS: Add support for XPA.").
    Signed-off-by: default avatarPaul Burton <paul.burton@imgtec.com>
    Reported-by: default avatarManuel Lauss <manuel.lauss@gmail.com>
    Tested-by: default avatarManuel Lauss <manuel.lauss@gmail.com>
    Fixes: c5b36783 ("MIPS: Add support for XPA.")
    Cc: James Hogan <james.hogan@imgtec.com>
    Cc: David Daney <david.daney@cavium.com>
    Cc: Huacai Chen <chenhc@lemote.com>
    Cc: Maciej W. Rozycki <macro@linux-mips.org>
    Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
    Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
    Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
    Cc: David Hildenbrand <dahi@linux.vnet.ibm.com>
    Cc: Andrew Morton <akpm@linux-foundation.org>
    Cc: Ingo Molnar <mingo@kernel.org>
    Cc: Alex Smith <alex.smith@imgtec.com>
    Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
    Cc: stable@vger.kernel.org # v4.1+
    Cc: linux-mips@linux-mips.org
    Cc: linux-kernel@vger.kernel.org
    Patchwork: https://patchwork.linux-mips.org/patch/13119/Signed-off-by: default avatarRalf Baechle <ralf@linux-mips.org>
    7b2cb64f
pgtable.h 17.3 KB