X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=arch%2Fpowerpc%2Fplatforms%2Fpseries%2Fsetup.c;h=5eb55ef1c91cd20a99ffe811596458c7d8acf326;hb=706c8c93ba4865a19e981b9770151a7a63c15794;hp=984241bb776c222c76b6e9d1ab8c939fb7391565;hpb=0941d57aa7034ef7010bd523752c2e3bee569ef1;p=linux-2.6 diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c index 984241bb77..5eb55ef1c9 100644 --- a/arch/powerpc/platforms/pseries/setup.c +++ b/arch/powerpc/platforms/pseries/setup.c @@ -60,7 +60,6 @@ #include #include #include "xics.h" -#include #include #include #include @@ -70,6 +69,7 @@ #include "plpar_wrappers.h" #include "ras.h" +#include "firmware.h" #ifdef DEBUG #define DBG(fmt...) udbg_printf(fmt) @@ -81,8 +81,8 @@ extern void find_udbg_vterm(void); int fwnmi_active; /* TRUE if an FWNMI handler is present */ -static void pseries_shared_idle(void); -static void pseries_dedicated_idle(void); +static void pseries_shared_idle_sleep(void); +static void pseries_dedicated_idle_sleep(void); struct mpic *pSeries_mpic; @@ -236,17 +236,16 @@ static void __init pSeries_setup_arch(void) vpa_init(boot_cpuid); if (get_lppaca()->shared_proc) { printk(KERN_INFO "Using shared processor idle loop\n"); - ppc_md.idle_loop = pseries_shared_idle; + ppc_md.power_save = pseries_shared_idle_sleep; } else { printk(KERN_INFO "Using dedicated idle loop\n"); - ppc_md.idle_loop = pseries_dedicated_idle; + ppc_md.power_save = pseries_dedicated_idle_sleep; } } else { printk(KERN_INFO "Using default idle loop\n"); - ppc_md.idle_loop = default_idle; } - if (platform_is_lpar()) + if (firmware_has_feature(FW_FEATURE_LPAR)) ppc_md.enable_pmcs = pseries_lpar_enable_pmcs; else ppc_md.enable_pmcs = power4_enable_pmcs; @@ -262,49 +261,6 @@ static int __init pSeries_init_panel(void) } arch_initcall(pSeries_init_panel); - -/* Build up the firmware features bitmask using the contents of - * device-tree/ibm,hypertas-functions. Ultimately this functionality may - * be moved into prom.c prom_init(). - */ -static void __init fw_feature_init(void) -{ - struct device_node *dn; - char *hypertas, *s; - int len, i; - - DBG(" -> fw_feature_init()\n"); - - dn = of_find_node_by_path("/rtas"); - if (dn == NULL) { - printk(KERN_ERR "WARNING! Cannot find RTAS in device-tree!\n"); - goto out; - } - - hypertas = get_property(dn, "ibm,hypertas-functions", &len); - if (hypertas == NULL) - goto out; - - for (s = hypertas; s < hypertas + len; s += strlen(s) + 1) { - for (i = 0; i < FIRMWARE_MAX_FEATURES; i++) { - /* check value against table of strings */ - if (!firmware_features_table[i].name || - strcmp(firmware_features_table[i].name, s)) - continue; - - /* we have a match */ - ppc64_firmware_features |= - firmware_features_table[i].val; - break; - } - } - -out: - of_node_put(dn); - DBG(" <- fw_feature_init()\n"); -} - - static void __init pSeries_discover_pic(void) { struct device_node *np; @@ -363,21 +319,16 @@ static int pseries_set_xdabr(unsigned long dabr) */ static void __init pSeries_init_early(void) { - int iommu_off = 0; - DBG(" -> pSeries_init_early()\n"); fw_feature_init(); - if (platform_is_lpar()) + if (firmware_has_feature(FW_FEATURE_LPAR)) hpte_init_lpar(); - else { + else hpte_init_native(); - iommu_off = (of_chosen && - get_property(of_chosen, "linux,iommu-off", NULL)); - } - if (platform_is_lpar()) + if (firmware_has_feature(FW_FEATURE_LPAR)) find_udbg_vterm(); if (firmware_has_feature(FW_FEATURE_DABR)) @@ -421,158 +372,128 @@ static int pSeries_check_legacy_ioport(unsigned int baseport) /* * Called very early, MMU is off, device-tree isn't unflattened */ -extern struct machdep_calls pSeries_md; -static int __init pSeries_probe(int platform) +static int __init pSeries_probe_hypertas(unsigned long node, + const char *uname, int depth, + void *data) { - if (platform != PLATFORM_PSERIES && - platform != PLATFORM_PSERIES_LPAR) - return 0; + if (depth != 1 || + (strcmp(uname, "rtas") != 0 && strcmp(uname, "rtas@0") != 0)) + return 0; - /* if we have some ppc_md fixups for LPAR to do, do - * it here ... - */ + if (of_get_flat_dt_prop(node, "ibm,hypertas-functions", NULL) != NULL) + powerpc_firmware_features |= FW_FEATURE_LPAR; - return 1; + return 1; } -DECLARE_PER_CPU(unsigned long, smt_snooze_delay); - -static inline void dedicated_idle_sleep(unsigned int cpu) +static int __init pSeries_probe(void) { - struct lppaca *plppaca = &lppaca[cpu ^ 1]; + char *dtype = of_get_flat_dt_prop(of_get_flat_dt_root(), + "device_type", NULL); + if (dtype == NULL) + return 0; + if (strcmp(dtype, "chrp")) + return 0; - /* Only sleep if the other thread is not idle */ - if (!(plppaca->idle)) { - local_irq_disable(); + DBG("pSeries detected, looking for LPAR capability...\n"); - /* - * 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(); - } + /* Now try to figure out if we are running on LPAR */ + of_scan_flat_dt(pSeries_probe_hypertas, NULL); + + DBG("Machine is%s LPAR !\n", + (powerpc_firmware_features & FW_FEATURE_LPAR) ? "" : " not"); + + return 1; } -static void pseries_dedicated_idle(void) + +DECLARE_PER_CPU(unsigned long, smt_snooze_delay); + +static void pseries_dedicated_idle_sleep(void) { 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. - */ - get_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(); - } - - get_lppaca()->idle = 0; - ppc64_runlatch_on(); - preempt_enable_no_resched(); - schedule(); - preempt_disable(); + /* + * Indicate to the HV that we are idle. Now would be + * a good time to find other work to dispatch. + */ + get_lppaca()->idle = 1; - if (cpu_is_offline(cpu) && system_state == SYSTEM_RUNNING) - cpu_die(); - } -} + /* + * We come in with interrupts disabled, and need_resched() + * has been checked recently. If we should poll for a little + * while, do so. + */ + if (*smt_snooze_delay) { + start_snooze = get_tb() + + *smt_snooze_delay * tb_ticks_per_usec; + local_irq_enable(); + set_thread_flag(TIF_POLLING_NRFLAG); -static void pseries_shared_idle(void) -{ - unsigned int cpu = smp_processor_id(); + while (get_tb() < start_snooze) { + if (need_resched() || cpu_is_offline(cpu)) + goto out; + ppc64_runlatch_off(); + HMT_low(); + HMT_very_low(); + } - while (1) { - /* - * Indicate to the HV that we are idle. Now would be - * a good time to find other work to dispatch. - */ - get_lppaca()->idle = 1; + HMT_medium(); + clear_thread_flag(TIF_POLLING_NRFLAG); + smp_mb(); + local_irq_disable(); + if (need_resched() || cpu_is_offline(cpu)) + goto out; + } - while (!need_resched() && !cpu_is_offline(cpu)) { - local_irq_disable(); - ppc64_runlatch_off(); + /* + * Cede if the other thread is not idle, so that it can + * go single-threaded. If the other thread is idle, + * we ask the hypervisor if it has pending work it + * wants to do and cede if it does. Otherwise we keep + * polling in order to reduce interrupt latency. + * + * Doing the cede when the other thread is active will + * result in this thread going dormant, meaning the other + * thread gets to run in single-threaded (ST) mode, which + * is slightly faster than SMT mode with this thread at + * very low priority. The cede enables interrupts, which + * doesn't matter here. + */ + if (!lppaca[cpu ^ 1].idle || poll_pending() == H_PENDING) + cede_processor(); - /* - * 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(); - } +out: + HMT_medium(); + get_lppaca()->idle = 0; +} - get_lppaca()->idle = 0; - ppc64_runlatch_on(); +static void pseries_shared_idle_sleep(void) +{ + /* + * Indicate to the HV that we are idle. Now would be + * a good time to find other work to dispatch. + */ + get_lppaca()->idle = 1; - preempt_enable_no_resched(); - schedule(); - preempt_disable(); + /* + * 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. + */ + cede_processor(); - if (cpu_is_offline(cpu) && system_state == SYSTEM_RUNNING) - cpu_die(); - } + get_lppaca()->idle = 0; } static int pSeries_pci_probe_mode(struct pci_bus *bus) { - if (platform_is_lpar()) + if (firmware_has_feature(FW_FEATURE_LPAR)) return PCI_PROBE_DEVTREE; return PCI_PROBE_NORMAL; } @@ -598,7 +519,8 @@ static void pseries_kexec_cpu_down(int crash_shutdown, int secondary) } #endif -struct machdep_calls __initdata pSeries_md = { +define_machine(pseries) { + .name = "pSeries", .probe = pSeries_probe, .setup_arch = pSeries_setup_arch, .init_early = pSeries_init_early,