From c7754d465b1feade85b5f1c4492781a30f6652a2 Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Tue, 15 May 2007 17:03:54 -0700 Subject: [SPARC64]: Add hypervisor API negotiation and fix console bugs. Hypervisor interfaces need to be negotiated in order to use some API calls reliably. So add a small set of interfaces to request API versions and query current settings. This allows us to fix some bugs in the hypervisor console: 1) If we can negotiate API group CORE of at least major 1 minor 1 we can use con_read and con_write which can improve console performance quite a bit. 2) When we do a console write request, we should hold the spinlock around the whole request, not a byte at a time. What would happen is that it's easy for output from different cpus to get mixed with each other. 3) Use consistent udelay() based polling, udelay(1) each loop with a limit of 1000 polls to handle stuck hypervisor console. Signed-off-by: David S. Miller --- arch/sparc64/kernel/Makefile | 2 +- arch/sparc64/kernel/entry.S | 94 +++++++++++++++++++++ arch/sparc64/kernel/hvapi.c | 189 +++++++++++++++++++++++++++++++++++++++++++ arch/sparc64/kernel/setup.c | 3 + 4 files changed, 287 insertions(+), 1 deletion(-) create mode 100644 arch/sparc64/kernel/hvapi.c (limited to 'arch') diff --git a/arch/sparc64/kernel/Makefile b/arch/sparc64/kernel/Makefile index 6bf6fb65bc20..c749dccacc32 100644 --- a/arch/sparc64/kernel/Makefile +++ b/arch/sparc64/kernel/Makefile @@ -12,7 +12,7 @@ obj-y := process.o setup.o cpu.o idprom.o \ irq.o ptrace.o time.o sys_sparc.o signal.o \ unaligned.o central.o pci.o starfire.o semaphore.o \ power.o sbus.o iommu_common.o sparc64_ksyms.o chmc.o \ - visemul.o prom.o of_device.o + visemul.o prom.o of_device.o hvapi.o obj-$(CONFIG_STACKTRACE) += stacktrace.o obj-$(CONFIG_PCI) += ebus.o isa.o pci_common.o pci_iommu.o \ diff --git a/arch/sparc64/kernel/entry.S b/arch/sparc64/kernel/entry.S index c15a3edcb826..732b77cb71f8 100644 --- a/arch/sparc64/kernel/entry.S +++ b/arch/sparc64/kernel/entry.S @@ -1843,3 +1843,97 @@ sun4v_cpu_state: mov %o1, %o0 1: retl nop + + /* %o0: API group number + * %o1: pointer to unsigned long major number storage + * %o2: pointer to unsigned long minor number storage + * + * returns %o0: status + */ + .globl sun4v_get_version +sun4v_get_version: + mov HV_CORE_GET_VER, %o5 + mov %o1, %o3 + mov %o2, %o4 + ta HV_CORE_TRAP + stx %o1, [%o3] + retl + stx %o2, [%o4] + + /* %o0: API group number + * %o1: desired major number + * %o2: desired minor number + * %o3: pointer to unsigned long actual minor number storage + * + * returns %o0: status + */ + .globl sun4v_set_version +sun4v_set_version: + mov HV_CORE_SET_VER, %o5 + mov %o3, %o4 + ta HV_CORE_TRAP + retl + stx %o1, [%o4] + + /* %o0: pointer to unsigned long status + * + * returns %o0: signed character + */ + .globl sun4v_con_getchar +sun4v_con_getchar: + mov %o0, %o4 + mov HV_FAST_CONS_GETCHAR, %o5 + clr %o0 + clr %o1 + ta HV_FAST_TRAP + stx %o0, [%o4] + retl + sra %o1, 0, %o0 + + /* %o0: signed long character + * + * returns %o0: status + */ + .globl sun4v_con_putchar +sun4v_con_putchar: + mov HV_FAST_CONS_PUTCHAR, %o5 + ta HV_FAST_TRAP + retl + sra %o0, 0, %o0 + + /* %o0: buffer real address + * %o1: buffer size + * %o2: pointer to unsigned long bytes_read + * + * returns %o0: status + */ + .globl sun4v_con_read +sun4v_con_read: + mov %o2, %o4 + mov HV_FAST_CONS_READ, %o5 + ta HV_FAST_TRAP + brnz %o0, 1f + cmp %o1, -1 /* break */ + be,a,pn %icc, 1f + mov %o1, %o0 + cmp %o1, -2 /* hup */ + be,a,pn %icc, 1f + mov %o1, %o0 + stx %o1, [%o4] +1: retl + nop + + /* %o0: buffer real address + * %o1: buffer size + * %o2: pointer to unsigned long bytes_written + * + * returns %o0: status + */ + .globl sun4v_con_write +sun4v_con_write: + mov %o2, %o4 + mov HV_FAST_CONS_WRITE, %o5 + ta HV_FAST_TRAP + stx %o1, [%o4] + retl + nop diff --git a/arch/sparc64/kernel/hvapi.c b/arch/sparc64/kernel/hvapi.c new file mode 100644 index 000000000000..f03ffc829c7a --- /dev/null +++ b/arch/sparc64/kernel/hvapi.c @@ -0,0 +1,189 @@ +/* hvapi.c: Hypervisor API management. + * + * Copyright (C) 2007 David S. Miller + */ +#include +#include +#include +#include + +#include +#include + +/* If the hypervisor indicates that the API setting + * calls are unsupported, by returning HV_EBADTRAP or + * HV_ENOTSUPPORTED, we assume that API groups with the + * PRE_API flag set are major 1 minor 0. + */ +struct api_info { + unsigned long group; + unsigned long major; + unsigned long minor; + unsigned int refcnt; + unsigned int flags; +#define FLAG_PRE_API 0x00000001 +}; + +static struct api_info api_table[] = { + { .group = HV_GRP_SUN4V, .flags = FLAG_PRE_API }, + { .group = HV_GRP_CORE, .flags = FLAG_PRE_API }, + { .group = HV_GRP_INTR, }, + { .group = HV_GRP_SOFT_STATE, }, + { .group = HV_GRP_PCI, .flags = FLAG_PRE_API }, + { .group = HV_GRP_LDOM, }, + { .group = HV_GRP_SVC_CHAN, .flags = FLAG_PRE_API }, + { .group = HV_GRP_NCS, .flags = FLAG_PRE_API }, + { .group = HV_GRP_NIAG_PERF, .flags = FLAG_PRE_API }, + { .group = HV_GRP_FIRE_PERF, }, + { .group = HV_GRP_DIAG, .flags = FLAG_PRE_API }, +}; + +static DEFINE_SPINLOCK(hvapi_lock); + +static struct api_info *__get_info(unsigned long group) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(api_table); i++) { + if (api_table[i].group == group) + return &api_table[i]; + } + return NULL; +} + +static void __get_ref(struct api_info *p) +{ + p->refcnt++; +} + +static void __put_ref(struct api_info *p) +{ + if (--p->refcnt == 0) { + unsigned long ignore; + + sun4v_set_version(p->group, 0, 0, &ignore); + p->major = p->minor = 0; + } +} + +/* Register a hypervisor API specification. It indicates the + * API group and desired major+minor. + * + * If an existing API registration exists '0' (success) will + * be returned if it is compatible with the one being registered. + * Otherwise a negative error code will be returned. + * + * Otherwise an attempt will be made to negotiate the requested + * API group/major/minor with the hypervisor, and errors returned + * if that does not succeed. + */ +int sun4v_hvapi_register(unsigned long group, unsigned long major, + unsigned long *minor) +{ + struct api_info *p; + unsigned long flags; + int ret; + + spin_lock_irqsave(&hvapi_lock, flags); + p = __get_info(group); + ret = -EINVAL; + if (p) { + if (p->refcnt) { + ret = -EINVAL; + if (p->major == major) { + *minor = p->minor; + ret = 0; + } + } else { + unsigned long actual_minor; + unsigned long hv_ret; + + hv_ret = sun4v_set_version(group, major, *minor, + &actual_minor); + ret = -EINVAL; + if (hv_ret == HV_EOK) { + *minor = actual_minor; + p->major = major; + p->minor = actual_minor; + ret = 0; + } else if (hv_ret == HV_EBADTRAP || + HV_ENOTSUPPORTED) { + if (p->flags & FLAG_PRE_API) { + if (major == 1) { + p->major = 1; + p->minor = 0; + *minor = 0; + ret = 0; + } + } + } + } + + if (ret == 0) + __get_ref(p); + } + spin_unlock_irqrestore(&hvapi_lock, flags); + + return ret; +} +EXPORT_SYMBOL(sun4v_hvapi_register); + +void sun4v_hvapi_unregister(unsigned long group) +{ + struct api_info *p; + unsigned long flags; + + spin_lock_irqsave(&hvapi_lock, flags); + p = __get_info(group); + if (p) + __put_ref(p); + spin_unlock_irqrestore(&hvapi_lock, flags); +} +EXPORT_SYMBOL(sun4v_hvapi_unregister); + +int sun4v_hvapi_get(unsigned long group, + unsigned long *major, + unsigned long *minor) +{ + struct api_info *p; + unsigned long flags; + int ret; + + spin_lock_irqsave(&hvapi_lock, flags); + ret = -EINVAL; + p = __get_info(group); + if (p && p->refcnt) { + *major = p->major; + *minor = p->minor; + ret = 0; + } + spin_unlock_irqrestore(&hvapi_lock, flags); + + return ret; +} +EXPORT_SYMBOL(sun4v_hvapi_get); + +void __init sun4v_hvapi_init(void) +{ + unsigned long group, major, minor; + + group = HV_GRP_SUN4V; + major = 1; + minor = 0; + if (sun4v_hvapi_register(group, major, &minor)) + goto bad; + + group = HV_GRP_CORE; + major = 1; + minor = 1; + if (sun4v_hvapi_register(group, major, &minor)) + goto bad; + + return; + +bad: + prom_printf("HVAPI: Cannot register API group " + "%lx with major(%u) minor(%u)\n", + group, major, minor); + prom_halt(); +} diff --git a/arch/sparc64/kernel/setup.c b/arch/sparc64/kernel/setup.c index 451028341c75..dea9c3c9ec5f 100644 --- a/arch/sparc64/kernel/setup.c +++ b/arch/sparc64/kernel/setup.c @@ -269,6 +269,7 @@ void __init per_cpu_patch(void) void __init sun4v_patch(void) { + extern void sun4v_hvapi_init(void); struct sun4v_1insn_patch_entry *p1; struct sun4v_2insn_patch_entry *p2; @@ -300,6 +301,8 @@ void __init sun4v_patch(void) p2++; } + + sun4v_hvapi_init(); } #ifdef CONFIG_SMP -- cgit v1.2.2