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authorDavid S. Miller <davem@davemloft.net>2009-01-21 21:30:23 -0800
committerDavid S. Miller <davem@davemloft.net>2009-01-28 17:13:57 -0800
commit3eb8057bbafc64dbf09d5c18513aa80c1b7f2fcb (patch)
tree77852bad482b27316d7333a2633b3fec61a4797b /arch/sparc/kernel/pcr.c
parent5376071069ec8a7e6a8112beab16fc24f5139475 (diff)
sparc64: Move generic PCR support code to seperate file.
It all lives in the oprofile support code currently and we will need to share this stuff with NMI watchdog and perf_counter support. Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'arch/sparc/kernel/pcr.c')
-rw-r--r--arch/sparc/kernel/pcr.c140
1 files changed, 140 insertions, 0 deletions
diff --git a/arch/sparc/kernel/pcr.c b/arch/sparc/kernel/pcr.c
new file mode 100644
index 000000000000..c4f24703b165
--- /dev/null
+++ b/arch/sparc/kernel/pcr.c
@@ -0,0 +1,140 @@
+/* pcr.c: Generic sparc64 performance counter infrastructure.
+ *
+ * Copyright (C) 2009 David S. Miller (davem@davemloft.net)
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/irq.h>
+
+#include <asm/pil.h>
+#include <asm/pcr.h>
+
+/* This code is shared between various users of the performance
+ * counters. Users will be oprofile, pseudo-NMI watchdog, and the
+ * perf_counter support layer.
+ */
+
+/* Performance counter interrupts run unmasked at PIL level 15.
+ * Therefore we can't do things like wakeups and other work
+ * that expects IRQ disabling to be adhered to in locking etc.
+ *
+ * Therefore in such situations we defer the work by signalling
+ * a lower level cpu IRQ.
+ */
+void deferred_pcr_work_irq(int irq, struct pt_regs *regs)
+{
+ clear_softint(1 << PIL_DEFERRED_PCR_WORK);
+}
+
+void schedule_deferred_pcr_work(void)
+{
+ set_softint(1 << PIL_DEFERRED_PCR_WORK);
+}
+
+const struct pcr_ops *pcr_ops;
+EXPORT_SYMBOL_GPL(pcr_ops);
+
+static u64 direct_pcr_read(void)
+{
+ u64 val;
+
+ read_pcr(val);
+ return val;
+}
+
+static void direct_pcr_write(u64 val)
+{
+ write_pcr(val);
+}
+
+static const struct pcr_ops direct_pcr_ops = {
+ .read = direct_pcr_read,
+ .write = direct_pcr_write,
+};
+
+static void n2_pcr_write(u64 val)
+{
+ unsigned long ret;
+
+ ret = sun4v_niagara2_setperf(HV_N2_PERF_SPARC_CTL, val);
+ if (val != HV_EOK)
+ write_pcr(val);
+}
+
+static const struct pcr_ops n2_pcr_ops = {
+ .read = direct_pcr_read,
+ .write = n2_pcr_write,
+};
+
+static unsigned long perf_hsvc_group;
+static unsigned long perf_hsvc_major;
+static unsigned long perf_hsvc_minor;
+
+static int __init register_perf_hsvc(void)
+{
+ if (tlb_type == hypervisor) {
+ switch (sun4v_chip_type) {
+ case SUN4V_CHIP_NIAGARA1:
+ perf_hsvc_group = HV_GRP_NIAG_PERF;
+ break;
+
+ case SUN4V_CHIP_NIAGARA2:
+ perf_hsvc_group = HV_GRP_N2_CPU;
+ break;
+
+ default:
+ return -ENODEV;
+ }
+
+
+ perf_hsvc_major = 1;
+ perf_hsvc_minor = 0;
+ if (sun4v_hvapi_register(perf_hsvc_group,
+ perf_hsvc_major,
+ &perf_hsvc_minor)) {
+ printk("perfmon: Could not register hvapi.\n");
+ return -ENODEV;
+ }
+ }
+ return 0;
+}
+
+static void __init unregister_perf_hsvc(void)
+{
+ if (tlb_type != hypervisor)
+ return;
+ sun4v_hvapi_unregister(perf_hsvc_group);
+}
+
+int __init pcr_arch_init(void)
+{
+ int err = register_perf_hsvc();
+
+ if (err)
+ return err;
+
+ switch (tlb_type) {
+ case hypervisor:
+ pcr_ops = &n2_pcr_ops;
+ break;
+
+ case spitfire:
+ case cheetah:
+ case cheetah_plus:
+ pcr_ops = &direct_pcr_ops;
+ break;
+
+ default:
+ err = -ENODEV;
+ goto out_unregister;
+ }
+
+ return 0;
+
+out_unregister:
+ unregister_perf_hsvc();
+ return err;
+}
+
+arch_initcall(pcr_arch_init);