static void cache_init()

in kernel/cpu/init.c [107:191]

• 47 lines of code
• 7 McCabe index (conditional complexity)

static void cache_init(void)
{
	unsigned long ccr, flags;

	jump_to_uncached();
	ccr = __raw_readl(SH_CCR);

	/*
	 * At this point we don't know whether the cache is enabled or not - a
	 * bootloader may have enabled it.  There are at least 2 things that
	 * could be dirty in the cache at this point:
	 * 1. kernel command line set up by boot loader
	 * 2. spilled registers from the prolog of this function
	 * => before re-initialising the cache, we must do a purge of the whole
	 * cache out to memory for safety.  As long as nothing is spilled
	 * during the loop to lines that have already been done, this is safe.
	 * - RPC
	 */
	if (ccr & CCR_CACHE_ENABLE) {
		unsigned long ways, waysize, addrstart;

		waysize = current_cpu_data.dcache.sets;

#ifdef CCR_CACHE_ORA
		/*
		 * If the OC is already in RAM mode, we only have
		 * half of the entries to flush..
		 */
		if (ccr & CCR_CACHE_ORA)
			waysize >>= 1;
#endif

		waysize <<= current_cpu_data.dcache.entry_shift;

#ifdef CCR_CACHE_EMODE
		/* If EMODE is not set, we only have 1 way to flush. */
		if (!(ccr & CCR_CACHE_EMODE))
			ways = 1;
		else
#endif
			ways = current_cpu_data.dcache.ways;

		addrstart = CACHE_OC_ADDRESS_ARRAY;
		do {
			unsigned long addr;

			for (addr = addrstart;
			     addr < addrstart + waysize;
			     addr += current_cpu_data.dcache.linesz)
				__raw_writel(0, addr);

			addrstart += current_cpu_data.dcache.way_incr;
		} while (--ways);
	}

	/*
	 * Default CCR values .. enable the caches
	 * and invalidate them immediately..
	 */
	flags = CCR_CACHE_ENABLE | CCR_CACHE_INVALIDATE;

#ifdef CCR_CACHE_EMODE
	/* Force EMODE if possible */
	if (current_cpu_data.dcache.ways > 1)
		flags |= CCR_CACHE_EMODE;
	else
		flags &= ~CCR_CACHE_EMODE;
#endif

#if defined(CONFIG_CACHE_WRITETHROUGH)
	/* Write-through */
	flags |= CCR_CACHE_WT;
#elif defined(CONFIG_CACHE_WRITEBACK)
	/* Write-back */
	flags |= CCR_CACHE_CB;
#else
	/* Off */
	flags &= ~CCR_CACHE_ENABLE;
#endif

	l2_cache_init();

	__raw_writel(flags, SH_CCR);
	back_to_cached();
}