setup.c

linux-2.6.15.6

	ppc64_interrupt_controller = IC_INVALID;
	for (np = NULL; (np = of_find_node_by_name(np, "interrupt-controller"));) {
		typep = (char *)get_property(np, "compatible", NULL);
		if (strstr(typep, "open-pic"))
			ppc64_interrupt_controller = IC_OPEN_PIC;
		else if (strstr(typep, "ppc-xicp"))
			ppc64_interrupt_controller = IC_PPC_XIC;
		else
			printk("pSeries_discover_pic: failed to recognize"
			       " interrupt-controller\n");
		break;
	}
}

static void pSeries_mach_cpu_die(void)
{
	local_irq_disable();
	idle_task_exit();
	/* Some hardware requires clearing the CPPR, while other hardware does not
	 * it is safe either way
	 */
	pSeriesLP_cppr_info(0, 0);
	rtas_stop_self();
	/* Should never get here... */
	BUG();
	for(;;);
}

static int pseries_set_dabr(unsigned long dabr)
{
	return plpar_hcall_norets(H_SET_DABR, dabr);
}

static int pseries_set_xdabr(unsigned long dabr)
{
	/* We want to catch accesses from kernel and userspace */
	return plpar_hcall_norets(H_SET_XDABR, dabr,
			H_DABRX_KERNEL | H_DABRX_USER);
}

/*
 * Early initialization.  Relocation is on but do not reference unbolted pages
 */
static void __init pSeries_init_early(void)
{
	void *comport;
	int iommu_off = 0;
	unsigned int default_speed;
	u64 physport;

	DBG(" -> pSeries_init_early()\n");

	fw_feature_init();
	
	if (platform_is_lpar())
		hpte_init_lpar();
	else {
		hpte_init_native();
		iommu_off = (of_chosen &&
			     get_property(of_chosen, "linux,iommu-off", NULL));
	}

	generic_find_legacy_serial_ports(&physport, &default_speed);

	if (platform_is_lpar())
		find_udbg_vterm();
	else if (physport) {
		/* Map the uart for udbg. */
		comport = (void *)ioremap(physport, 16);
		udbg_init_uart(comport, default_speed);

		DBG("Hello World !\n");
	}

	if (firmware_has_feature(FW_FEATURE_DABR))
		ppc_md.set_dabr = pseries_set_dabr;
	else if (firmware_has_feature(FW_FEATURE_XDABR))
		ppc_md.set_dabr = pseries_set_xdabr;

	iommu_init_early_pSeries();

	pSeries_discover_pic();

	DBG(" <- pSeries_init_early()\n");
}


static int pSeries_check_legacy_ioport(unsigned int baseport)
{
	struct device_node *np;

#define I8042_DATA_REG	0x60
#define FDC_BASE	0x3f0


	switch(baseport) {
	case I8042_DATA_REG:
		np = of_find_node_by_type(NULL, "8042");
		if (np == NULL)
			return -ENODEV;
		of_node_put(np);
		break;
	case FDC_BASE:
		np = of_find_node_by_type(NULL, "fdc");
		if (np == NULL)
			return -ENODEV;
		of_node_put(np);
		break;
	}
	return 0;
}

/*
 * Called very early, MMU is off, device-tree isn't unflattened
 */
extern struct machdep_calls pSeries_md;

static int __init pSeries_probe(int platform)
{
	if (platform != PLATFORM_PSERIES &&
	    platform != PLATFORM_PSERIES_LPAR)
		return 0;

	/* if we have some ppc_md fixups for LPAR to do, do
	 * it here ...
	 */

	return 1;
}

DECLARE_PER_CPU(unsigned long, smt_snooze_delay);

static inline void dedicated_idle_sleep(unsigned int cpu)
{
	struct paca_struct *ppaca = &paca[cpu ^ 1];

	/* Only sleep if the other thread is not idle */
	if (!(ppaca->lppaca.idle)) {
		local_irq_disable();

		/*
		 * We are about to sleep the thread and so wont be polling any
		 * more.
		 */
		clear_thread_flag(TIF_POLLING_NRFLAG);
		smp_mb__after_clear_bit();

		/*
		 * SMT dynamic mode. Cede will result in this thread going
		 * dormant, if the partner thread is still doing work.  Thread
		 * wakes up if partner goes idle, an interrupt is presented, or
		 * a prod occurs.  Returning from the cede enables external
		 * interrupts.
		 */
		if (!need_resched())
			cede_processor();
		else
			local_irq_enable();
		set_thread_flag(TIF_POLLING_NRFLAG);
	} else {
		/*
		 * Give the HV an opportunity at the processor, since we are
		 * not doing any work.
		 */
		poll_pending();
	}
}

static void pseries_dedicated_idle(void)
{ 
	struct paca_struct *lpaca = get_paca();
	unsigned int cpu = smp_processor_id();
	unsigned long start_snooze;
	unsigned long *smt_snooze_delay = &__get_cpu_var(smt_snooze_delay);
	set_thread_flag(TIF_POLLING_NRFLAG);

	while (1) {
		/*
		 * Indicate to the HV that we are idle. Now would be
		 * a good time to find other work to dispatch.
		 */
		lpaca->lppaca.idle = 1;

		if (!need_resched()) {
			start_snooze = get_tb() +
				*smt_snooze_delay * tb_ticks_per_usec;

			while (!need_resched() && !cpu_is_offline(cpu)) {
				ppc64_runlatch_off();

				/*
				 * Go into low thread priority and possibly
				 * low power mode.
				 */
				HMT_low();
				HMT_very_low();

				if (*smt_snooze_delay != 0 &&
				    get_tb() > start_snooze) {
					HMT_medium();
					dedicated_idle_sleep(cpu);
				}

			}

			HMT_medium();
		}

		lpaca->lppaca.idle = 0;
		ppc64_runlatch_on();

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

		if (cpu_is_offline(cpu) && system_state == SYSTEM_RUNNING)
			cpu_die();
	}
}

static void pseries_shared_idle(void)
{
	struct paca_struct *lpaca = get_paca();
	unsigned int cpu = smp_processor_id();

	while (1) {
		/*
		 * Indicate to the HV that we are idle. Now would be
		 * a good time to find other work to dispatch.
		 */
		lpaca->lppaca.idle = 1;

		while (!need_resched() && !cpu_is_offline(cpu)) {
			local_irq_disable();
			ppc64_runlatch_off();

			/*
			 * Yield the processor to the hypervisor.  We return if
			 * an external interrupt occurs (which are driven prior
			 * to returning here) or if a prod occurs from another
			 * processor. When returning here, external interrupts
			 * are enabled.
			 *
			 * Check need_resched() again with interrupts disabled
			 * to avoid a race.
			 */
			if (!need_resched())
				cede_processor();
			else
				local_irq_enable();

			HMT_medium();
		}

		lpaca->lppaca.idle = 0;
		ppc64_runlatch_on();

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

		if (cpu_is_offline(cpu) && system_state == SYSTEM_RUNNING)
			cpu_die();
	}
}

static int pSeries_pci_probe_mode(struct pci_bus *bus)
{
	if (platform_is_lpar())
		return PCI_PROBE_DEVTREE;
	return PCI_PROBE_NORMAL;
}

#ifdef CONFIG_KEXEC
static void pseries_kexec_cpu_down(int crash_shutdown, int secondary)
{
	/* Don't risk a hypervisor call if we're crashing */
	if (!crash_shutdown) {
		unsigned long vpa = __pa(&get_paca()->lppaca);

		if (unregister_vpa(hard_smp_processor_id(), vpa)) {
			printk("VPA deregistration of cpu %u (hw_cpu_id %d) "
					"failed\n", smp_processor_id(),
					hard_smp_processor_id());
		}
	}

	if (ppc64_interrupt_controller == IC_OPEN_PIC)
		mpic_teardown_this_cpu(secondary);
	else
		xics_teardown_cpu(secondary);
}
#endif

struct machdep_calls __initdata pSeries_md = {
	.probe			= pSeries_probe,
	.setup_arch		= pSeries_setup_arch,
	.init_early		= pSeries_init_early,
	.show_cpuinfo		= pSeries_show_cpuinfo,
	.log_error		= pSeries_log_error,
	.pcibios_fixup		= pSeries_final_fixup,
	.pci_probe_mode		= pSeries_pci_probe_mode,
	.irq_bus_setup		= pSeries_irq_bus_setup,
	.restart		= rtas_restart,
	.power_off		= rtas_power_off,
	.halt			= rtas_halt,
	.panic			= rtas_os_term,
	.cpu_die		= pSeries_mach_cpu_die,
	.get_boot_time		= rtas_get_boot_time,
	.get_rtc_time		= rtas_get_rtc_time,
	.set_rtc_time		= rtas_set_rtc_time,
	.calibrate_decr		= generic_calibrate_decr,
	.progress		= rtas_progress,
	.check_legacy_ioport	= pSeries_check_legacy_ioport,
	.system_reset_exception = pSeries_system_reset_exception,
	.machine_check_exception = pSeries_machine_check_exception,
#ifdef CONFIG_KEXEC
	.kexec_cpu_down		= pseries_kexec_cpu_down,
#endif
};