From: Benjamin Herrenschmidt Date: Tue, 5 Jul 2016 05:03:49 +0000 (+1000) Subject: powerpc: Put exception configuration in a common place X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=d3cbff1b5a90afe6cb201aa2187c9609e21f92ad;p=deliverable%2Flinux.git powerpc: Put exception configuration in a common place The various calls to establish exception endianness and AIL are now done from a single point using already established CPU and FW feature bits to decide what to do. Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Michael Ellerman --- diff --git a/arch/powerpc/include/asm/hvcall.h b/arch/powerpc/include/asm/hvcall.h index 0bc9c284aa10..708edebcf147 100644 --- a/arch/powerpc/include/asm/hvcall.h +++ b/arch/powerpc/include/asm/hvcall.h @@ -431,17 +431,6 @@ static inline unsigned long cmo_get_page_size(void) { return CMO_PageSize; } - -extern long pSeries_enable_reloc_on_exc(void); -extern long pSeries_disable_reloc_on_exc(void); - -extern long pseries_big_endian_exceptions(void); - -#else - -#define pSeries_enable_reloc_on_exc() do {} while (0) -#define pSeries_disable_reloc_on_exc() do {} while (0) - #endif /* CONFIG_PPC_PSERIES */ #endif /* __ASSEMBLY__ */ diff --git a/arch/powerpc/include/asm/opal.h b/arch/powerpc/include/asm/opal.h index b656bb192b63..ee05bd203630 100644 --- a/arch/powerpc/include/asm/opal.h +++ b/arch/powerpc/include/asm/opal.h @@ -234,6 +234,7 @@ extern int early_init_dt_scan_opal(unsigned long node, const char *uname, int depth, void *data); extern int early_init_dt_scan_recoverable_ranges(unsigned long node, const char *uname, int depth, void *data); +extern void opal_configure_cores(void); extern int opal_get_chars(uint32_t vtermno, char *buf, int count); extern int opal_put_chars(uint32_t vtermno, const char *buf, int total_len); diff --git a/arch/powerpc/include/asm/setup.h b/arch/powerpc/include/asm/setup.h index e9d384cbd021..654d64c9f3ac 100644 --- a/arch/powerpc/include/asm/setup.h +++ b/arch/powerpc/include/asm/setup.h @@ -26,6 +26,18 @@ void initmem_init(void); void setup_panic(void); #define ARCH_PANIC_TIMEOUT 180 +#ifdef CONFIG_PPC_PSERIES +extern void pseries_enable_reloc_on_exc(void); +extern void pseries_disable_reloc_on_exc(void); +extern void pseries_big_endian_exceptions(void); +extern void pseries_little_endian_exceptions(void); +#else +static inline void pseries_enable_reloc_on_exc(void) {} +static inline void pseries_disable_reloc_on_exc(void) {} +static inline void pseries_big_endian_exceptions(void) {} +static inline void pseries_little_endian_exceptions(void) {} +#endif /* CONFIG_PPC_PSERIES */ + #endif /* !__ASSEMBLY__ */ #endif /* _ASM_POWERPC_SETUP_H */ diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c index 155dbcce8ef8..4ffd090633de 100644 --- a/arch/powerpc/kernel/setup_64.c +++ b/arch/powerpc/kernel/setup_64.c @@ -69,6 +69,7 @@ #include #include #include +#include #ifdef DEBUG #define DBG(fmt...) udbg_printf(fmt) @@ -205,23 +206,50 @@ static void fixup_boot_paca(void) get_paca()->data_offset = 0; } -static void cpu_ready_for_interrupts(void) +static void configure_exceptions(void) { - /* Set IR and DR in PACA MSR */ - get_paca()->kernel_msr = MSR_KERNEL; - /* - * Enable AIL if supported, and we are in hypervisor mode. If we are - * not in hypervisor mode, we enable relocation-on interrupts later - * in pSeries_setup_arch() using the H_SET_MODE hcall. + * Setup the trampolines from the lowmem exception vectors + * to the kdump kernel when not using a relocatable kernel. */ - if (cpu_has_feature(CPU_FTR_HVMODE) && - cpu_has_feature(CPU_FTR_ARCH_207S)) { - unsigned long lpcr = mfspr(SPRN_LPCR); - mtspr(SPRN_LPCR, lpcr | LPCR_AIL_3); + setup_kdump_trampoline(); + + /* Under a PAPR hypervisor, we need hypercalls */ + if (firmware_has_feature(FW_FEATURE_SET_MODE)) { + /* Enable AIL if possible */ + pseries_enable_reloc_on_exc(); + + /* + * Tell the hypervisor that we want our exceptions to + * be taken in little endian mode. + * + * We don't call this for big endian as our calling convention + * makes us always enter in BE, and the call may fail under + * some circumstances with kdump. + */ +#ifdef __LITTLE_ENDIAN__ + pseries_little_endian_exceptions(); +#endif + } else { + /* Set endian mode using OPAL */ + if (firmware_has_feature(FW_FEATURE_OPAL)) + opal_configure_cores(); + + /* Enable AIL if supported, and we are in hypervisor mode */ + if (cpu_has_feature(CPU_FTR_HVMODE) && + cpu_has_feature(CPU_FTR_ARCH_207S)) { + unsigned long lpcr = mfspr(SPRN_LPCR); + mtspr(SPRN_LPCR, lpcr | LPCR_AIL_3); + } } } +static void cpu_ready_for_interrupts(void) +{ + /* Set IR and DR in PACA MSR */ + get_paca()->kernel_msr = MSR_KERNEL; +} + /* * Early initialization entry point. This is called by head.S * with MMU translation disabled. We rely on the "feature" of @@ -277,10 +305,10 @@ void __init early_setup(unsigned long dt_ptr) probe_machine(); /* - * Setup the trampolines from the lowmem exception vectors - * to the kdump kernel when not using a relocatable kernel. + * Configure exception handlers. This include setting up trampolines + * if needed, setting exception endian mode, etc... */ - setup_kdump_trampoline(); + configure_exceptions(); /* Initialize the hash table or TLB handling */ early_init_mmu(); diff --git a/arch/powerpc/kvm/book3s_pr.c b/arch/powerpc/kvm/book3s_pr.c index 8e4f64f0b774..c4f7d6b86b9e 100644 --- a/arch/powerpc/kvm/book3s_pr.c +++ b/arch/powerpc/kvm/book3s_pr.c @@ -35,7 +35,7 @@ #include #include #include -#include +#include #include #include #include @@ -1690,7 +1690,7 @@ static int kvmppc_core_init_vm_pr(struct kvm *kvm) if (firmware_has_feature(FW_FEATURE_SET_MODE)) { spin_lock(&kvm_global_user_count_lock); if (++kvm_global_user_count == 1) - pSeries_disable_reloc_on_exc(); + pseries_disable_reloc_on_exc(); spin_unlock(&kvm_global_user_count_lock); } return 0; @@ -1706,7 +1706,7 @@ static void kvmppc_core_destroy_vm_pr(struct kvm *kvm) spin_lock(&kvm_global_user_count_lock); BUG_ON(kvm_global_user_count == 0); if (--kvm_global_user_count == 0) - pSeries_enable_reloc_on_exc(); + pseries_enable_reloc_on_exc(); spin_unlock(&kvm_global_user_count_lock); } } diff --git a/arch/powerpc/platforms/powernv/opal.c b/arch/powerpc/platforms/powernv/opal.c index da40d6bdb0e6..8b4fc68cebcb 100644 --- a/arch/powerpc/platforms/powernv/opal.c +++ b/arch/powerpc/platforms/powernv/opal.c @@ -57,7 +57,7 @@ static struct atomic_notifier_head opal_msg_notifier_head[OPAL_MSG_TYPE_MAX]; static uint32_t opal_heartbeat; static struct task_struct *kopald_tsk; -static void opal_reinit_cores(void) +void opal_configure_cores(void) { /* Do the actual re-init, This will clobber all FPRs, VRs, etc... * @@ -70,6 +70,10 @@ static void opal_reinit_cores(void) #else opal_reinit_cpus(OPAL_REINIT_CPUS_HILE_LE); #endif + + /* Restore some bits */ + if (cur_cpu_spec->cpu_restore) + cur_cpu_spec->cpu_restore(); } int __init early_init_dt_scan_opal(unsigned long node, @@ -106,13 +110,6 @@ int __init early_init_dt_scan_opal(unsigned long node, panic("OPAL != V3 detected, no longer supported.\n"); } - /* Reinit all cores with the right endian */ - opal_reinit_cores(); - - /* Restore some bits */ - if (cur_cpu_spec->cpu_restore) - cur_cpu_spec->cpu_restore(); - return 1; } diff --git a/arch/powerpc/platforms/pseries/lpar.c b/arch/powerpc/platforms/pseries/lpar.c index 03ff9867a610..03c732afef34 100644 --- a/arch/powerpc/platforms/pseries/lpar.c +++ b/arch/powerpc/platforms/pseries/lpar.c @@ -261,24 +261,8 @@ static void pSeries_lpar_hptab_clear(void) * This is also called on boot when a fadump happens. In that case we * must not change the exception endian mode. */ - if (firmware_has_feature(FW_FEATURE_SET_MODE) && !is_fadump_active()) { - long rc; - - rc = pseries_big_endian_exceptions(); - /* - * At this point it is unlikely panic() will get anything - * out to the user, but at least this will stop us from - * continuing on further and creating an even more - * difficult to debug situation. - * - * There is a known problem when kdump'ing, if cpus are offline - * the above call will fail. Rather than panicking again, keep - * going and hope the kdump kernel is also little endian, which - * it usually is. - */ - if (rc && !kdump_in_progress()) - panic("Could not enable big endian exceptions"); - } + if (firmware_has_feature(FW_FEATURE_SET_MODE) && !is_fadump_active()) + pseries_big_endian_exceptions(); #endif } diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c index 9cc9b88fce79..ba7dc126b5e5 100644 --- a/arch/powerpc/platforms/pseries/setup.c +++ b/arch/powerpc/platforms/pseries/setup.c @@ -319,15 +319,23 @@ static void pseries_lpar_idle(void) * to ever be a problem in practice we can move this into a kernel thread to * finish off the process later in boot. */ -long pSeries_enable_reloc_on_exc(void) +void pseries_enable_reloc_on_exc(void) { long rc; unsigned int delay, total_delay = 0; while (1) { rc = enable_reloc_on_exceptions(); - if (!H_IS_LONG_BUSY(rc)) - return rc; + if (!H_IS_LONG_BUSY(rc)) { + if (rc == H_P2) { + pr_info("Relocation on exceptions not" + " supported\n"); + } else if (rc != H_SUCCESS) { + pr_warn("Unable to enable relocation" + " on exceptions: %ld\n", rc); + } + break; + } delay = get_longbusy_msecs(rc); total_delay += delay; @@ -335,66 +343,81 @@ long pSeries_enable_reloc_on_exc(void) pr_warn("Warning: Giving up waiting to enable " "relocation on exceptions (%u msec)!\n", total_delay); - return rc; + return; } mdelay(delay); } } -EXPORT_SYMBOL(pSeries_enable_reloc_on_exc); +EXPORT_SYMBOL(pseries_enable_reloc_on_exc); -long pSeries_disable_reloc_on_exc(void) +void pseries_disable_reloc_on_exc(void) { long rc; while (1) { rc = disable_reloc_on_exceptions(); if (!H_IS_LONG_BUSY(rc)) - return rc; + break; mdelay(get_longbusy_msecs(rc)); } + if (rc != H_SUCCESS) + pr_warning("Warning: Failed to disable relocation on " + "exceptions: %ld\n", rc); } -EXPORT_SYMBOL(pSeries_disable_reloc_on_exc); +EXPORT_SYMBOL(pseries_disable_reloc_on_exc); #ifdef CONFIG_KEXEC static void pSeries_machine_kexec(struct kimage *image) { - long rc; - - if (firmware_has_feature(FW_FEATURE_SET_MODE)) { - rc = pSeries_disable_reloc_on_exc(); - if (rc != H_SUCCESS) - pr_warning("Warning: Failed to disable relocation on " - "exceptions: %ld\n", rc); - } + if (firmware_has_feature(FW_FEATURE_SET_MODE)) + pseries_disable_reloc_on_exc(); default_machine_kexec(image); } #endif #ifdef __LITTLE_ENDIAN__ -long pseries_big_endian_exceptions(void) +void pseries_big_endian_exceptions(void) { long rc; while (1) { rc = enable_big_endian_exceptions(); if (!H_IS_LONG_BUSY(rc)) - return rc; + break; mdelay(get_longbusy_msecs(rc)); } + + /* + * At this point it is unlikely panic() will get anything + * out to the user, since this is called very late in kexec + * but at least this will stop us from continuing on further + * and creating an even more difficult to debug situation. + * + * There is a known problem when kdump'ing, if cpus are offline + * the above call will fail. Rather than panicking again, keep + * going and hope the kdump kernel is also little endian, which + * it usually is. + */ + if (rc && !kdump_in_progress()) + panic("Could not enable big endian exceptions"); } -static long pseries_little_endian_exceptions(void) +void pseries_little_endian_exceptions(void) { long rc; while (1) { rc = enable_little_endian_exceptions(); if (!H_IS_LONG_BUSY(rc)) - return rc; + break; mdelay(get_longbusy_msecs(rc)); } + if (rc) { + ppc_md.progress("H_SET_MODE LE exception fail", 0); + panic("Could not enable little endian exceptions"); + } } #endif @@ -464,18 +487,6 @@ static void __init pSeries_setup_arch(void) } ppc_md.pcibios_root_bridge_prepare = pseries_root_bridge_prepare; - - if (firmware_has_feature(FW_FEATURE_SET_MODE)) { - long rc; - - rc = pSeries_enable_reloc_on_exc(); - if (rc == H_P2) { - pr_info("Relocation on exceptions not supported\n"); - } else if (rc != H_SUCCESS) { - pr_warn("Unable to enable relocation on exceptions: " - "%ld\n", rc); - } - } } static int __init pSeries_init_panel(void) @@ -678,23 +689,6 @@ static int __init pSeries_probe(void) pr_debug("pSeries detected, looking for LPAR capability...\n"); - -#ifdef __LITTLE_ENDIAN__ - if (firmware_has_feature(FW_FEATURE_SET_MODE)) { - long rc; - /* - * Tell the hypervisor that we want our exceptions to - * be taken in little endian mode. If this fails we don't - * want to use BUG() because it will trigger an exception. - */ - rc = pseries_little_endian_exceptions(); - if (rc) { - ppc_md.progress("H_SET_MODE LE exception fail", 0); - panic("Could not enable little endian exceptions"); - } - } -#endif - if (firmware_has_feature(FW_FEATURE_LPAR)) hpte_init_lpar(); else