[lkml]   [2007]   [Apr]   [3]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
    Patch in this message
    Subject[PATCH 1/4] Implement mtrr_save_fixed_ranges()
    This patch implements mtrr_save_fixed_ranges() which can be called
    from anywhere anytime to retrieve the fixed-range MTRRs from the
    current CPU and saves these MTRR values to the MTRR state struct.

    This function calls get_fixed_ranges(), passing mtrr_state.fixed_ranges
    which is the element of the static struct which stores our current
    backup of the fixed-range MTRR values which all CPUs shall be

    Because mtrr_save_fixed_ranges calls get_fixed_ranges() after
    kernel initialisation time, __init needs to be removed from
    the declaration of get_fixed_ranges().

    Signed-off-by: Bernhard Kaindl <>

    --- linux-2.6.20.orig/arch/i386/kernel/cpu/mtrr/generic.c
    +++ linux-2.6.20/arch/i386/kernel/cpu/mtrr/generic.c
    @@ -37,7 +37,11 @@ get_mtrr_var_range(unsigned int index, s
    rdmsr(MTRRphysMask_MSR(index), vr->mask_lo, vr->mask_hi);

    -static void __init
    + * Retrieves the current fixed-range MTRRs from the current CPU
    + * \param frs address where to write the current MTRR contents
    + */
    +static void
    get_fixed_ranges(mtrr_type * frs)
    unsigned int *p = (unsigned int *) frs;
    @@ -51,6 +55,16 @@ get_fixed_ranges(mtrr_type * frs)
    rdmsr(MTRRfix4K_C0000_MSR + i, p[6 + i * 2], p[7 + i * 2]);

    + * Updates our copy of the state of the fixed-range MTRR values
    + * with the current fixed-range MTRR contents from the current CPU
    + * \param info dummy needed for use by smp_call_function_single()
    + */
    +void mtrr_save_fixed_ranges(void *info)
    + get_fixed_ranges(mtrr_state.fixed_ranges);
    static void __init print_fixed(unsigned base, unsigned step, const mtrr_type*types)
    unsigned i;
    Index: linux-2.6.20/include/asm-i386/mtrr.h
    --- linux-2.6.20.orig/include/asm-i386/mtrr.h
    +++ linux-2.6.20/include/asm-i386/mtrr.h
    @@ -69,6 +69,7 @@ struct mtrr_gentry

    /* The following functions are for use by other drivers */
    # ifdef CONFIG_MTRR
    +extern void mtrr_save_fixed_ranges(void *);
    extern int mtrr_add (unsigned long base, unsigned long size,
    unsigned int type, char increment);
    extern int mtrr_add_page (unsigned long base, unsigned long size,
    @@ -79,6 +80,7 @@ extern void mtrr_centaur_report_mcr(int
    extern void mtrr_ap_init(void);
    extern void mtrr_bp_init(void);
    # else
    +#define mtrr_save_fixed_ranges(arg) do {} while (0)
    static __inline__ int mtrr_add (unsigned long base, unsigned long size,
    unsigned int type, char increment)
    Index: linux-2.6.20/include/asm-x86_64/proto.h
    --- linux-2.6.20.orig/include/asm-x86_64/proto.h
    +++ linux-2.6.20/include/asm-x86_64/proto.h
    @@ -19,9 +19,11 @@ extern void mcheck_init(struct cpuinfo_x
    #ifdef CONFIG_MTRR
    extern void mtrr_ap_init(void);
    extern void mtrr_bp_init(void);
    +extern void mtrr_save_fixed_ranges(void *);
    #define mtrr_ap_init() do {} while (0)
    #define mtrr_bp_init() do {} while (0)
    +#define mtrr_save_fixed_ranges(arg) do {} while (0)
    extern void init_memory_mapping(unsigned long start, unsigned long end);

    In this current implementation, which is used in other patches,
    mtrr_save_fixed_ranges() accepts a dummy void pointer because
    in the current implementation of one of these patches, this
    function may be called from smp_call_function_single() which
    requires that this function takes a void pointer argument.
    If CONFIG_MTRR is not set, we define mtrr_save_fixed_ranges
    as an empty statement because there is nothing to do.
    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to
    More majordomo info at
    Please read the FAQ at

     \ /
      Last update: 2007-04-03 16:23    [W:0.023 / U:2.340 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site