setup.c

linux 内核源代码

 */

static unsigned long __init build_iSeries_Memory_Map(void)
{
	u32 loadAreaFirstChunk, loadAreaLastChunk, loadAreaSize;
	u32 nextPhysChunk;
	u32 hptFirstChunk, hptLastChunk, hptSizeChunks, hptSizePages;
	u32 totalChunks,moreChunks;
	u32 currChunk, thisChunk, absChunk;
	u32 currDword;
	u32 chunkBit;
	u64 map;
	struct MemoryBlock mb[32];
	unsigned long numMemoryBlocks, curBlock;

	/* Chunk size on iSeries is 256K bytes */
	totalChunks = (u32)HvLpConfig_getMsChunks();
	mschunks_alloc(totalChunks);

	/*
	 * Get absolute address of our load area
	 * and map it to physical address 0
	 * This guarantees that the loadarea ends up at physical 0
	 * otherwise, it might not be returned by PLIC as the first
	 * chunks
	 */

	loadAreaFirstChunk = (u32)addr_to_chunk(itLpNaca.xLoadAreaAddr);
	loadAreaSize =  itLpNaca.xLoadAreaChunks;

	/*
	 * Only add the pages already mapped here.
	 * Otherwise we might add the hpt pages
	 * The rest of the pages of the load area
	 * aren't in the HPT yet and can still
	 * be assigned an arbitrary physical address
	 */
	if ((loadAreaSize * 64) > HvPagesToMap)
		loadAreaSize = HvPagesToMap / 64;

	loadAreaLastChunk = loadAreaFirstChunk + loadAreaSize - 1;

	/*
	 * TODO Do we need to do something if the HPT is in the 64MB load area?
	 * This would be required if the itLpNaca.xLoadAreaChunks includes
	 * the HPT size
	 */

	printk("Mapping load area - physical addr = 0000000000000000\n"
		"                    absolute addr = %016lx\n",
		chunk_to_addr(loadAreaFirstChunk));
	printk("Load area size %dK\n", loadAreaSize * 256);

	for (nextPhysChunk = 0; nextPhysChunk < loadAreaSize; ++nextPhysChunk)
		mschunks_map.mapping[nextPhysChunk] =
			loadAreaFirstChunk + nextPhysChunk;

	/*
	 * Get absolute address of our HPT and remember it so
	 * we won't map it to any physical address
	 */
	hptFirstChunk = (u32)addr_to_chunk(HvCallHpt_getHptAddress());
	hptSizePages = (u32)HvCallHpt_getHptPages();
	hptSizeChunks = hptSizePages >>
		(MSCHUNKS_CHUNK_SHIFT - HW_PAGE_SHIFT);
	hptLastChunk = hptFirstChunk + hptSizeChunks - 1;

	printk("HPT absolute addr = %016lx, size = %dK\n",
			chunk_to_addr(hptFirstChunk), hptSizeChunks * 256);

	/*
	 * Determine if absolute memory has any
	 * holes so that we can interpret the
	 * access map we get back from the hypervisor
	 * correctly.
	 */
	numMemoryBlocks = iSeries_process_mainstore_vpd(mb, 32);

	/*
	 * Process the main store access map from the hypervisor
	 * to build up our physical -> absolute translation table
	 */
	curBlock = 0;
	currChunk = 0;
	currDword = 0;
	moreChunks = totalChunks;

	while (moreChunks) {
		map = HvCallSm_get64BitsOfAccessMap(itLpNaca.xLpIndex,
				currDword);
		thisChunk = currChunk;
		while (map) {
			chunkBit = map >> 63;
			map <<= 1;
			if (chunkBit) {
				--moreChunks;
				while (thisChunk >= mb[curBlock].logicalEnd) {
					++curBlock;
					if (curBlock >= numMemoryBlocks)
						panic("out of memory blocks");
				}
				if (thisChunk < mb[curBlock].logicalStart)
					panic("memory block error");

				absChunk = mb[curBlock].absStart +
					(thisChunk - mb[curBlock].logicalStart);
				if (((absChunk < hptFirstChunk) ||
				     (absChunk > hptLastChunk)) &&
				    ((absChunk < loadAreaFirstChunk) ||
				     (absChunk > loadAreaLastChunk))) {
					mschunks_map.mapping[nextPhysChunk] =
						absChunk;
					++nextPhysChunk;
				}
			}
			++thisChunk;
		}
		++currDword;
		currChunk += 64;
	}

	/*
	 * main store size (in chunks) is
	 *   totalChunks - hptSizeChunks
	 * which should be equal to
	 *   nextPhysChunk
	 */
	return chunk_to_addr(nextPhysChunk);
}

/*
 * Document me.
 */
static void __init iSeries_setup_arch(void)
{
	if (get_lppaca()->shared_proc) {
		ppc_md.idle_loop = iseries_shared_idle;
		printk(KERN_DEBUG "Using shared processor idle loop\n");
	} else {
		ppc_md.idle_loop = iseries_dedicated_idle;
		printk(KERN_DEBUG "Using dedicated idle loop\n");
	}

	/* Setup the Lp Event Queue */
	setup_hvlpevent_queue();

	printk("Max  logical processors = %d\n",
			itVpdAreas.xSlicMaxLogicalProcs);
	printk("Max physical processors = %d\n",
			itVpdAreas.xSlicMaxPhysicalProcs);
}

static void iSeries_show_cpuinfo(struct seq_file *m)
{
	seq_printf(m, "machine\t\t: 64-bit iSeries Logical Partition\n");
}

static void __init iSeries_progress(char * st, unsigned short code)
{
	printk("Progress: [%04x] - %s\n", (unsigned)code, st);
	mf_display_progress(code);
}

static void __init iSeries_fixup_klimit(void)
{
	/*
	 * Change klimit to take into account any ram disk
	 * that may be included
	 */
	if (naca.xRamDisk)
		klimit = KERNELBASE + (u64)naca.xRamDisk +
			(naca.xRamDiskSize * HW_PAGE_SIZE);
}

static int __init iSeries_src_init(void)
{
        /* clear the progress line */
	if (firmware_has_feature(FW_FEATURE_ISERIES))
		ppc_md.progress(" ", 0xffff);
        return 0;
}

late_initcall(iSeries_src_init);

static inline void process_iSeries_events(void)
{
	asm volatile ("li 0,0x5555; sc" : : : "r0", "r3");
}

static void yield_shared_processor(void)
{
	unsigned long tb;

	HvCall_setEnabledInterrupts(HvCall_MaskIPI |
				    HvCall_MaskLpEvent |
				    HvCall_MaskLpProd |
				    HvCall_MaskTimeout);

	tb = get_tb();
	/* Compute future tb value when yield should expire */
	HvCall_yieldProcessor(HvCall_YieldTimed, tb+tb_ticks_per_jiffy);

	/*
	 * The decrementer stops during the yield.  Force a fake decrementer
	 * here and let the timer_interrupt code sort out the actual time.
	 */
	get_lppaca()->int_dword.fields.decr_int = 1;
	ppc64_runlatch_on();
	process_iSeries_events();
}

static void iseries_shared_idle(void)
{
	while (1) {
		tick_nohz_stop_sched_tick();
		while (!need_resched() && !hvlpevent_is_pending()) {
			local_irq_disable();
			ppc64_runlatch_off();

			/* Recheck with irqs off */
			if (!need_resched() && !hvlpevent_is_pending())
				yield_shared_processor();

			HMT_medium();
			local_irq_enable();
		}

		ppc64_runlatch_on();
		tick_nohz_restart_sched_tick();

		if (hvlpevent_is_pending())
			process_iSeries_events();

		preempt_enable_no_resched();
		schedule();
		preempt_disable();
	}
}

static void iseries_dedicated_idle(void)
{
	set_thread_flag(TIF_POLLING_NRFLAG);

	while (1) {
		tick_nohz_stop_sched_tick();
		if (!need_resched()) {
			while (!need_resched()) {
				ppc64_runlatch_off();
				HMT_low();

				if (hvlpevent_is_pending()) {
					HMT_medium();
					ppc64_runlatch_on();
					process_iSeries_events();
				}
			}

			HMT_medium();
		}

		ppc64_runlatch_on();
		tick_nohz_restart_sched_tick();
		preempt_enable_no_resched();
		schedule();
		preempt_disable();
	}
}

static void __iomem *iseries_ioremap(phys_addr_t address, unsigned long size,
				     unsigned long flags)
{
	return (void __iomem *)address;
}

static void iseries_iounmap(volatile void __iomem *token)
{
}

static int __init iseries_probe(void)
{
	unsigned long root = of_get_flat_dt_root();
	if (!of_flat_dt_is_compatible(root, "IBM,iSeries"))
		return 0;

	hpte_init_iSeries();
	/* iSeries does not support 16M pages */
	cur_cpu_spec->cpu_features &= ~CPU_FTR_16M_PAGE;

	return 1;
}

define_machine(iseries) {
	.name		= "iSeries",
	.setup_arch	= iSeries_setup_arch,
	.show_cpuinfo	= iSeries_show_cpuinfo,
	.init_IRQ	= iSeries_init_IRQ,
	.get_irq	= iSeries_get_irq,
	.init_early	= iSeries_init_early,
	.pcibios_fixup	= iSeries_pci_final_fixup,
	.restart	= mf_reboot,
	.power_off	= mf_power_off,
	.halt		= mf_power_off,
	.get_boot_time	= iSeries_get_boot_time,
	.set_rtc_time	= iSeries_set_rtc_time,
	.get_rtc_time	= iSeries_get_rtc_time,
	.calibrate_decr	= generic_calibrate_decr,
	.progress	= iSeries_progress,
	.probe		= iseries_probe,
	.ioremap	= iseries_ioremap,
	.iounmap	= iseries_iounmap,
	/* XXX Implement enable_pmcs for iSeries */
};

void * __init iSeries_early_setup(void)
{
	unsigned long phys_mem_size;

	/* Identify CPU type. This is done again by the common code later
	 * on but calling this function multiple times is fine.
	 */
	identify_cpu(0, mfspr(SPRN_PVR));

	powerpc_firmware_features |= FW_FEATURE_ISERIES;
	powerpc_firmware_features |= FW_FEATURE_LPAR;

	iSeries_fixup_klimit();

	/*
	 * Initialize the table which translate Linux physical addresses to
	 * AS/400 absolute addresses
	 */
	phys_mem_size = build_iSeries_Memory_Map();

	iSeries_get_cmdline();

	return (void *) __pa(build_flat_dt(phys_mem_size));
}

static void hvputc(char c)
{
	if (c == '\n')
		hvputc('\r');

	HvCall_writeLogBuffer(&c, 1);
}

void __init udbg_init_iseries(void)
{
	udbg_putc = hvputc;
}