Re: [PATCH 9/11] Atari: add ndelay() (used by isp116x-hcd)

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On Thu, May 24, 2012 at 2:53 AM, Michael Schmitz
<schmitz@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx> wrote:
+#if defined(CONFIG_M68000) || defined(CONFIG_COLDFIRE)
+/*
+ * The simpler m68k and ColdFire processors do not have a 32*32->64
+ * multiply instruction. So we need to handle them a little differently.
+ * We use a bit of shifting and a single 32*32->32 multiply to get close.
+ * This is a macro so that the const version can factor out the first
+ * multiply and shift.
+ */
+#define        HZSCALE         (268435456 / (1000000 / HZ))
+
+#define ndelay(n) __delay( DIV_ROUND_UP( (n) * ((((HZSCALE) >> 11) * (loops_per_jiffy >> 11)) >> 6), 1000 ) );
+
+#endif

Why do you need this? CONFIG_M68000 and CONFIG_COLDFIRE are not set?

You end up using the default implementation in include/linux/delay.h.

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds
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