diff options
Diffstat (limited to 'kernel/arch/ia64/lib/clear_page.S')
| -rw-r--r-- | kernel/arch/ia64/lib/clear_page.S | 76 |
1 files changed, 76 insertions, 0 deletions
diff --git a/kernel/arch/ia64/lib/clear_page.S b/kernel/arch/ia64/lib/clear_page.S new file mode 100644 index 000000000..2d814e7ed --- /dev/null +++ b/kernel/arch/ia64/lib/clear_page.S @@ -0,0 +1,76 @@ +/* + * Copyright (C) 1999-2002 Hewlett-Packard Co + * Stephane Eranian <eranian@hpl.hp.com> + * David Mosberger-Tang <davidm@hpl.hp.com> + * Copyright (C) 2002 Ken Chen <kenneth.w.chen@intel.com> + * + * 1/06/01 davidm Tuned for Itanium. + * 2/12/02 kchen Tuned for both Itanium and McKinley + * 3/08/02 davidm Some more tweaking + */ + +#include <asm/asmmacro.h> +#include <asm/page.h> + +#ifdef CONFIG_ITANIUM +# define L3_LINE_SIZE 64 // Itanium L3 line size +# define PREFETCH_LINES 9 // magic number +#else +# define L3_LINE_SIZE 128 // McKinley L3 line size +# define PREFETCH_LINES 12 // magic number +#endif + +#define saved_lc r2 +#define dst_fetch r3 +#define dst1 r8 +#define dst2 r9 +#define dst3 r10 +#define dst4 r11 + +#define dst_last r31 + +GLOBAL_ENTRY(clear_page) + .prologue + .regstk 1,0,0,0 + mov r16 = PAGE_SIZE/L3_LINE_SIZE-1 // main loop count, -1=repeat/until + .save ar.lc, saved_lc + mov saved_lc = ar.lc + + .body + mov ar.lc = (PREFETCH_LINES - 1) + mov dst_fetch = in0 + adds dst1 = 16, in0 + adds dst2 = 32, in0 + ;; +.fetch: stf.spill.nta [dst_fetch] = f0, L3_LINE_SIZE + adds dst3 = 48, in0 // executing this multiple times is harmless + br.cloop.sptk.few .fetch + ;; + addl dst_last = (PAGE_SIZE - PREFETCH_LINES*L3_LINE_SIZE), dst_fetch + mov ar.lc = r16 // one L3 line per iteration + adds dst4 = 64, in0 + ;; +#ifdef CONFIG_ITANIUM + // Optimized for Itanium +1: stf.spill.nta [dst1] = f0, 64 + stf.spill.nta [dst2] = f0, 64 + cmp.lt p8,p0=dst_fetch, dst_last + ;; +#else + // Optimized for McKinley +1: stf.spill.nta [dst1] = f0, 64 + stf.spill.nta [dst2] = f0, 64 + stf.spill.nta [dst3] = f0, 64 + stf.spill.nta [dst4] = f0, 128 + cmp.lt p8,p0=dst_fetch, dst_last + ;; + stf.spill.nta [dst1] = f0, 64 + stf.spill.nta [dst2] = f0, 64 +#endif + stf.spill.nta [dst3] = f0, 64 +(p8) stf.spill.nta [dst_fetch] = f0, L3_LINE_SIZE + br.cloop.sptk.few 1b + ;; + mov ar.lc = saved_lc // restore lc + br.ret.sptk.many rp +END(clear_page) |