Tarun, > -----Original Message----- > From: linux-omap-owner@xxxxxxxxxxxxxxx [mailto:linux-omap-owner@xxxxxxxxxxxxxxx] On Behalf Of > Manjunatha GK > Sent: Thursday, April 01, 2010 8:54 PM > To: linux-omap@xxxxxxxxxxxxxxx > Cc: DebBarma, Tarun Kanti; Siarhei Siamashka; G, Manjunath Kondaiah > Subject: [PATCH] OMAP GPTimer for OProfile(Errata#628216) > > From: DebBarma, Tarun Kanti <tarun.kanti@xxxxxx> > > [ARM Cortex-A8 Errata 628216] > If a Perf Counter OVFL occurs simultaneously with an update to a CP14 or > CP15 register, the OVFL status can be lost. > > In order to workaround problem in Cortex-A8 Performance Counter, OMAP > GPTIMER is used by OProfile. > > Signed-off-by: Tarun Kanti DebBarma <tarun.kanti@xxxxxx> > Cc: Siarhei Siamashka <siarhei.siamashka@xxxxxxxxx> > Cc: Manjunatha GK <manjugk@xxxxxx> > --- > arch/arm/Kconfig | 59 +++++++++++++++--- > arch/arm/oprofile/Makefile | 1 + > arch/arm/oprofile/common.c | 4 + > arch/arm/oprofile/op_arm_model.h | 1 + > arch/arm/oprofile/op_model_omap_gptimer.c | 96 +++++++++++++++++++++++++++++ > 5 files changed, 153 insertions(+), 8 deletions(-) > create mode 100644 arch/arm/oprofile/op_model_omap_gptimer.c > > diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig > index 410d3e3..a753c8c 100644 > --- a/arch/arm/Kconfig > +++ b/arch/arm/Kconfig > @@ -175,27 +175,70 @@ config ARM_L1_CACHE_SHIFT_6 > help > Setting ARM L1 cache line size to 64 Bytes. > > -if OPROFILE > +menuconfig INSTRUMENTATION > + bool "Instrumentation Support" > + default y > + ---help--- > + Say Y here to get to see options related to performance measurement, > + system-wide debugging and testing. This option alone does not add any > + kernel code. > + > + If you say N, all options in this submenu will be skipped and > + disabled. If you're trying to debug the kernel itself, check the > + Kernel Hacking menu. > + > +if INSTRUMENTATION > + > +config PROFILING > + bool "Profiling support" > + help > + Say Y here to enable the extended profiling support mechanisms > + used by profilers such as OProfile. > + > +config OPROFILE > + tristate "OProfile system profiling" > + depends on PROFILING > + help > + OProfile is a profiling system capable of profiling the > + whole system, including the kernel, kernel modules, libraries, > + and applications. > + > + If unsure, say N. > +choice > + prompt "Oprofile Mode" > + depends on OPROFILE > + default OPROFILE_OMAP_GPTIMER > > config OPROFILE_ARMV6 > - def_bool y > + bool "Oprofile ARMv6" > depends on CPU_V6 && !SMP > select OPROFILE_ARM11_CORE > > config OPROFILE_MPCORE > - def_bool y > + bool "Oprofile MPcore" > depends on CPU_V6 && SMP > select OPROFILE_ARM11_CORE > > -config OPROFILE_ARM11_CORE > - bool > - > config OPROFILE_ARMV7 > - def_bool y > + bool "Oprofile ARMv7" > depends on CPU_V7 && !SMP > + help > + Uses Performance counters for profiling > + > +config OPROFILE_OMAP_GPTIMER > + bool "Oprofile GPTimer" > + depends on ARCH_OMAP > + select OMAP_32K_TIMER > + select OMAP_DM_TIMER > + help > + Uses GPTIMER for profiling. Currently this is the preferred > + way since Performance counters have known bugs in Cortex-A8 > +endchoice > + > +config OPROFILE_ARM11_CORE > bool > > -endif > +endif # INSTRUMENTATION Do you need so many KConfig entries?? > config VECTORS_BASE > hex > diff --git a/arch/arm/oprofile/Makefile b/arch/arm/oprofile/Makefile > index 88e31f5..fc2bc02 100644 > --- a/arch/arm/oprofile/Makefile > +++ b/arch/arm/oprofile/Makefile > @@ -8,6 +8,7 @@ DRIVER_OBJS = $(addprefix ../../../drivers/oprofile/, \ > > oprofile-y := $(DRIVER_OBJS) common.o backtrace.o > oprofile-$(CONFIG_CPU_XSCALE) += op_model_xscale.o > +oprofile-$(CONFIG_OPROFILE_OMAP_GPTIMER) += op_model_omap_gptimer.o > oprofile-$(CONFIG_OPROFILE_ARM11_CORE) += op_model_arm11_core.o > oprofile-$(CONFIG_OPROFILE_ARMV6) += op_model_v6.o > oprofile-$(CONFIG_OPROFILE_MPCORE) += op_model_mpcore.o > diff --git a/arch/arm/oprofile/common.c b/arch/arm/oprofile/common.c > index 3fcd752..9eb2b9b 100644 > --- a/arch/arm/oprofile/common.c > +++ b/arch/arm/oprofile/common.c > @@ -133,6 +133,10 @@ int __init oprofile_arch_init(struct oprofile_operations *ops) > > ops->backtrace = arm_backtrace; > > +#ifdef CONFIG_OPROFILE_OMAP_GPTIMER > + spec = &op_omap_gptimer_spec; > +#endif > + > #ifdef CONFIG_CPU_XSCALE > spec = &op_xscale_spec; > #endif > diff --git a/arch/arm/oprofile/op_arm_model.h b/arch/arm/oprofile/op_arm_model.h > index 8c4e4f6..55f22e4 100644 > --- a/arch/arm/oprofile/op_arm_model.h > +++ b/arch/arm/oprofile/op_arm_model.h > @@ -24,6 +24,7 @@ struct op_arm_model_spec { > extern struct op_arm_model_spec op_xscale_spec; > #endif > > +extern struct op_arm_model_spec op_omap_gptimer_spec; > extern struct op_arm_model_spec op_armv6_spec; > extern struct op_arm_model_spec op_mpcore_spec; > extern struct op_arm_model_spec op_armv7_spec; > diff --git a/arch/arm/oprofile/op_model_omap_gptimer.c b/arch/arm/oprofile/op_model_omap_gptimer.c > new file mode 100644 > index 0000000..49bab30 > --- /dev/null > +++ b/arch/arm/oprofile/op_model_omap_gptimer.c > @@ -0,0 +1,96 @@ > +/** > + * OMAP gptimer based event monitor driver for oprofile > + * > + * Copyright (C) 2009 Nokia Corporation > + * Author: Siarhei Siamashka <siarhei.siamashka@xxxxxxxxx> > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License version 2 as > + * published by the Free Software Foundation. > + * > + */ > + > +#include <linux/types.h> > +#include <linux/oprofile.h> > +#include <linux/interrupt.h> > +#include <linux/irq.h> > +#include <plat/dmtimer.h> > + > +#include "op_counter.h" > +#include "op_arm_model.h" > + > +static struct omap_dm_timer *gptimer; > + > +static int gptimer_init(void) > +{ > + return 0; > +} > + > +static int gptimer_setup(void) > +{ > + return 0; > +} > + > +static irqreturn_t gptimer_interrupt(int irq, void *arg) > +{ > + omap_dm_timer_write_status(gptimer, OMAP_TIMER_INT_OVERFLOW); > + oprofile_add_sample(get_irq_regs(), 0); > + return IRQ_HANDLED; > +} > + > +static int gptimer_start(void) > +{ > + int err; > + u32 count = counter_config[0].count; > + > + BUG_ON(gptimer != NULL); > + /* First try to request timers from CORE power domain for OMAP3 */ If any timer is ok, why specific timer ? > + if (cpu_is_omap34xx()) { > + gptimer = omap_dm_timer_request_specific(10); > + if (gptimer == NULL) > + gptimer = omap_dm_timer_request_specific(11); > + } > + /* Just any timer would be fine */ > + if (gptimer == NULL) > + gptimer = omap_dm_timer_request(); > + > + if (gptimer == NULL) > + return -ENODEV; > + > + omap_dm_timer_set_source(gptimer, OMAP_TIMER_SRC_32_KHZ); With Sys clock this can give better resolution o.w any accuracy below ~30 uS is lost. > + err = request_irq(omap_dm_timer_get_irq(gptimer), gptimer_interrupt, > + IRQF_DISABLED, "oprofile gptimer", NULL); > + if (err) { > + omap_dm_timer_free(gptimer); > + gptimer = NULL; > + printk(KERN_ERR "oprofile: unable to request gptimer IRQ\n"); > + return err; > + } > + > + /* opcontrol sets default value as 100000 which makes the sample rate > + * too low, hence resetting > + */ > + if ((count < 0) || (count == 100000)) > + count = 1; > + > + omap_dm_timer_set_load_start(gptimer, 1, 0xffffffff - count); > + omap_dm_timer_set_int_enable(gptimer, OMAP_TIMER_INT_OVERFLOW); > + return 0; > +} > + > +static void gptimer_stop(void) > +{ > + omap_dm_timer_set_int_enable(gptimer, 0); > + free_irq(omap_dm_timer_get_irq(gptimer), NULL); > + omap_dm_timer_free(gptimer); > + gptimer = NULL; > +} > + > +struct op_arm_model_spec op_omap_gptimer_spec = { > + .init = gptimer_init, > + .num_counters = 1, > + .setup_ctrs = gptimer_setup, > + .start = gptimer_start, > + .stop = gptimer_stop, > + .name = "arm/armv6", This is done for Cortex-A8 right which is armv7 > +}; > -- > 1.6.0.4 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-omap" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
