• Tony Lindgren's avatar
    pstore-ram: Allow optional mapping with pgprot_noncached · 027bc8b0
    Tony Lindgren authored
    On some ARMs the memory can be mapped pgprot_noncached() and still
    be working for atomic operations. As pointed out by Colin Cross
    <ccross@android.com>, in some cases you do want to use
    pgprot_noncached() if the SoC supports it to see a debug printk
    just before a write hanging the system.
    On ARMs, the atomic operations on strongly ordered memory are
    implementation defined. So let's provide an optional kernel parameter
    for configuring pgprot_noncached(), and use pgprot_writecombine() by
    Cc: Arnd Bergmann <arnd@arndb.de>
    Cc: Rob Herring <robherring2@gmail.com>
    Cc: Randy Dunlap <rdunlap@infradead.org>
    Cc: Anton Vorontsov <anton@enomsg.org>
    Cc: Colin Cross <ccross@android.com>
    Cc: Olof Johansson <olof@lixom.net>
    Cc: Russell King <linux@arm.linux.org.uk>
    Cc: stable@vger.kernel.org
    Acked-by: default avatarKees Cook <keescook@chromium.org>
    Signed-off-by: default avatarTony Lindgren <tony@atomide.com>
    Signed-off-by: default avatarTony Luck <tony.luck@intel.com>
ramoops.txt 5.21 KB