linaro-dev November 2010

linaro-dev@lists.linaro.org

73 participants
81 discussions

by Ira Rosen

Hi, After working fine for a while, the board crashed during the weekend, and I am getting the following error: Texas Instruments X-Loader 1.4.4ss (Sep 30 2010 - 14:44:32) Beagle xM Rev A Reading boot sector not there u-boot.bin not found or blank nand contents - attempting serial boot . . . ## Ready for binary (kermit) download to 0x80008000 at 115200 bps.. The SD card was formatted and reinstalled: ./linaro-media-create --mmc /dev/mmcblk0 --dev beagle --binary image/linaro-m-headless-tar-*.tar.gz --hwpack ../hwpack_linaro-omap3_20101105-75_armel_supported.tar.gz but it didn't help. The card seems to be OK: root@idol-laptop:~# df Filesystem 1K-blocks Used Available Use% Mounted on /dev/sda2 144183992 38735348 98124484 29% / none 1574348 372 1573976 1% /dev none 1578568 5204 1573364 1% /dev/shm none 1578568 120 1578448 1% /var/run none 1578568 0 1578568 0% /var/lock none 1578568 0 1578568 0% /lib/init/rw /dev/mmcblk0p2 3731768 360100 3182104 11% /media/rootfs /dev/mmcblk0p1 71133 8481 62653 12% /media/boot ls -l /media/boot/ total 8480 -rwxr-xr-x 1 idol idol 397 2010-11-21 11:39 boot.ini -rwxr-xr-x 1 idol idol 397 2010-11-21 11:39 boot.scr -rwxr-xr-x 1 idol idol 18360 2010-11-21 11:39 MLO -rwxr-xr-x 1 idol idol 192204 2010-11-21 11:39 u-boot.bin -rwxr-xr-x 1 idol idol 3704228 2010-11-21 11:39 uImage -rwxr-xr-x 1 idol idol 4766721 2010-11-21 11:39 uInitrd ls -l /media/rootfs/ total 784 drwxr-xr-x 2 root root 4096 2010-11-21 06:46 bin drwxr-xr-x 2 root root 4096 2010-11-21 11:36 boot drwxr-xr-x 4 root root 4096 2010-11-21 06:42 dev drwxr-xr-x 60 root root 4096 2010-11-21 11:41 etc drwxr-xr-x 2 root root 4096 2010-10-07 11:15 home lrwxrwxrwx 1 root root 39 2010-11-21 11:39 initrd.img -> boot/initrd.img-2.6.35-1006-linaro-omap drwxr-xr-x 10 root root 4096 2010-11-21 06:45 lib drwx------ 2 root root 16384 2010-11-21 11:36 lost+found -rw-r--r-- 1 root root 708215 2010-11-21 06:48 md5sum.txt drwxr-xr-x 2 root root 4096 2010-11-21 06:41 media drwxr-xr-x 2 root root 4096 2010-10-07 11:15 mnt drwxr-xr-x 2 root root 4096 2010-11-21 06:41 opt drwxr-xr-x 2 root root 4096 2010-10-07 11:15 proc drwx------ 2 root root 4096 2010-11-21 11:59 root drwxr-xr-x 2 root root 4096 2010-11-21 11:34 sbin drwxr-xr-x 2 root root 4096 2010-05-09 21:20 selinux drwxr-xr-x 2 root root 4096 2010-11-21 06:41 srv drwxr-xr-x 2 root root 4096 2010-09-25 00:05 sys drwxrwxrwt 2 root root 4096 2010-11-21 11:36 tmp drwxr-xr-x 10 root root 4096 2010-11-21 06:41 usr drwxr-xr-x 13 root root 4096 2010-11-21 06:38 var lrwxrwxrwx 1 root root 36 2010-11-21 11:41 vmlinuz -> boot/vmlinuz-2.6.35-1006-linaro-omap fdisk -l Disk /dev/mmcblk0: 3959 MB, 3959422976 bytes 255 heads, 63 sectors/track, 481 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x00042b57 Device Boot Start End Blocks Id System /dev/mmcblk0p1 * 1 9 72261 c W95 FAT32 (LBA) /dev/mmcblk0p2 10 481 3791340 83 Linux Any clue? Thanks, Ira

13 years, 11 months

[PATCH V2] ARM: SAMSUNG: Add support for clock debugging through debug-fs interface

by Amit Daniel Kachhap

This patch adds support for clock information exposed to debug-fs interface. Signed-off-by: Amit Daniel Kachhap <amit.daniel(a)samsung.com> --- Code modified for V2 version are, a)Inserted the debug-fs code inside macro CONFIG_PM_DEBUG as suggested by yong.shen(a)linaro.org. b)Removed macro CONFIG_PLAT_SAMSUNG and implemented other coding standards as suggested by kgene.kim(a)samsung.com arch/arm/plat-samsung/clock.c | 91 ++++++++++++++++++++++++++++ arch/arm/plat-samsung/include/plat/clock.h | 3 + 2 files changed, 94 insertions(+), 0 deletions(-) diff --git a/arch/arm/plat-samsung/clock.c b/arch/arm/plat-samsung/clock.c index e8d20b0..029a49d 100644 --- a/arch/arm/plat-samsung/clock.c +++ b/arch/arm/plat-samsung/clock.c @@ -39,6 +39,9 @@ #include <linux/clk.h> #include <linux/spinlock.h> #include <linux/io.h> +#if defined(CONFIG_DEBUG_FS) +#include <linux/debugfs.h> +#endif #include <mach/hardware.h> #include <asm/irq.h> @@ -447,3 +450,91 @@ int __init s3c24xx_register_baseclocks(unsigned long xtal) return 0; } +#if defined(CONFIG_PM_DEBUG) && defined(CONFIG_DEBUG_FS) +/* debugfs support to trace clock tree hierarchy and attributes */ + +static struct dentry *clk_debugfs_root; + +static int clk_debugfs_register_one(struct clk *c) +{ + int err; + struct dentry *d, *child, *child_tmp; + struct clk *pa = c->parent; + char s[255]; + char *p = s; + + p += sprintf(p, "%s", c->name); + /*Append id field with name also*/ + if (c->id >= 0) + sprintf(p, ":%d", c->id); + + d = debugfs_create_dir(s, pa ? pa->dent : clk_debugfs_root); + if (!d) + return -ENOMEM; + + c->dent = d; + + d = debugfs_create_u8("usecount", S_IRUGO, c->dent, (u8 *)&c->usage); + if (!d) { + err = -ENOMEM; + goto err_out; + } + d = debugfs_create_u32("rate", S_IRUGO, c->dent, (u32 *)&c->rate); + if (!d) { + err = -ENOMEM; + goto err_out; + } + return 0; + +err_out: + d = c->dent; + list_for_each_entry_safe(child, child_tmp, &d->d_subdirs, d_u.d_child) + debugfs_remove(child); + debugfs_remove(c->dent); + return err; +} + +static int clk_debugfs_register(struct clk *c) +{ + int err; + struct clk *pa = c->parent; + + if (pa && !pa->dent) { + err = clk_debugfs_register(pa); + if (err) + return err; + } + + if (!c->dent) { + err = clk_debugfs_register_one(c); + if (err) + return err; + } + return 0; +} + +static int __init clk_debugfs_init(void) +{ + struct clk *c; + struct dentry *d; + int err; + + d = debugfs_create_dir("clock", NULL); + if (!d) + return -ENOMEM; + clk_debugfs_root = d; + + list_for_each_entry(c, &clocks, list) { + err = clk_debugfs_register(c); + if (err) + goto err_out; + } + return 0; +err_out: + debugfs_remove_recursive(clk_debugfs_root); + return err; +} +late_initcall(clk_debugfs_init); + +#endif /* defined(CONFIG_PM_DEBUG) && defined(CONFIG_DEBUG_FS) */ + diff --git a/arch/arm/plat-samsung/include/plat/clock.h b/arch/arm/plat-samsung/include/plat/clock.h index 0fbcd0e..9a82b88 100644 --- a/arch/arm/plat-samsung/include/plat/clock.h +++ b/arch/arm/plat-samsung/include/plat/clock.h @@ -47,6 +47,9 @@ struct clk { struct clk_ops *ops; int (*enable)(struct clk *, int enable); +#if defined(CONFIG_PM_DEBUG) && defined(CONFIG_DEBUG_FS) + struct dentry *dent; /* For visible tree hierarchy */ +#endif }; /* other clocks which may be registered by board support */ -- 1.6.2.5

13 years, 11 months

license for setup_sdcard.sh

by John Rigby

Hi Robert, The Linaro project has a script that started as your setup_sdcard.sh called linaro_media_create. As part of our release process we need to have licenses for our files and since our script is based on yours, your choice of license affects what choices we have. So long story short, your file has no license included so care to add one or just tell us what the license is so we can give our script a compatible if not identical one? Thanks John

14 years

Direct link to latest image

by Loïc Minier

Hey folks I'd like to mirror and test the latest build of http://snapshots.linaro.org/10.11-daily/linaro-headless/ but I have two issues with this: * having some kind of direct link to the latest image so that I don't need to parse the HTML to get the latest build; something like /latest/ or /current/ would help here * having a constant name for the data as to be rsync friendly; that is, if the image is named linaro-m-headless-tar-20100923-0.tar.gz and linaro-m-headless-tar-20100924-0.tar.gz the next day, it's hard to convince rsync that the data file from the 24th can be mostly inferred from the contents of the 23th; if it was named linaro-m-headless-tar.tar.gz, I would have no problem Where should I be filing bugs to track these requests, and who should I harass to get these resolved? :-) Thanks! -- Loïc Minier

14 years

[PATCH] OMAP PM: Optimize cpufreq transition latency

by Vishwanath BS

Currently cpufreq transition latency value does not really reflect the actual OMAP OPP transition delay. This patch has the actual latency value. I did profile the DVFS latency on OMAP3430, OMAP3630 and OMAP4 for worstcase(MPU and Core together) and found that in none of these platforms, transiton value goes beyong 10ms. Added a buffer of 20ms to avoid too frequent ondemand timer expiry. With this change, performance of ondemand governor is improved when tested using cpufreqbench tool. Without this patch, cpufreq-bench reported ondemand performance as 40% of performance governor, and with this patch it's around 70% (using below procedure). cpufreq-bench: http://lwn.net/Articles/339862/ http://ftp.riken.go.jp/archives/Linux/suse/people/ckornacker/cpufreq-bench/ Command used for performance testing: cpufreq-bench -l 50000 -s 100000 -x 50000 -y 100000 -g ondemand -r 5 -n 5 -v Signed-off-by: Vishwanath BS <vishwanath.bs(a)ti.com> --- arch/arm/plat-omap/cpu-omap.c | 4 ++-- 1 files changed, 2 insertions(+), 2 deletions(-) mode change 100644 => 100755 arch/arm/plat-omap/cpu-omap.c diff --git a/arch/arm/plat-omap/cpu-omap.c b/arch/arm/plat-omap/cpu-omap.c old mode 100644 new mode 100755 index c47faf8..d3fc423 --- a/arch/arm/plat-omap/cpu-omap.c +++ b/arch/arm/plat-omap/cpu-omap.c @@ -158,8 +158,8 @@ static int __init omap_cpu_init(struct cpufreq_policy *policy) policy->max = policy->cpuinfo.max_freq; policy->cur = omap_getspeed(0); - /* FIXME: what's the actual transition time? */ - policy->cpuinfo.transition_latency = 300 * 1000; + /* Program the actual transition time for worstcase */ + policy->cpuinfo.transition_latency = 30 * 1000; return 0; } -- 1.7.0.4

14 years

Please include ux500 core into linux-next

by Linus Walleij

Hi Stephen, please consider to start merging our ux500-core branch into linux-next: git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-stericsson.git Branch: ux500-core (NB: there is a "next" branch, which include patches to multiple subsystems, don't merge that, this is just the ux500 core.) I rebase this regularly to Torvalds' -rc tags, hope that's OK. All code is being reviewed on the linux-arm-kernel list, and the patches here are intended for pull request to Russell King who in turn take them upstream. I hope this procedure is acceptable. We currently have some of these patches in Russells patch tracker as well, but they will be taken out in favor of the pull approach once this branch lands in -next. Yours, Linus Walleij

14 years

git.linaro.org gitweb busted?

by john stultz

When I use http://git.linaro.org/gitweb I'm getting xml errors when I click through on to any of the git repos. ie: http://git.linaro.org/gitweb?p=linux/arm_next.git;a=summary XML Parsing Error: undefined entity Location: http://git.linaro.org/gitweb?p=linux/arm_next.git;a=summary Line Number 41, Column 20: <div class="title"> </div> -------------------^ Any thoughts on whats gone wrong? thanks -john

14 years

Minutes & actions: Kernel Working Group meeting of Nov 29, 2010

by Mounir Bsaibes

Greetings, Enclosed you'll find a link to the agenda, minutes and actions from the Linaro kernel working group weekly meeting of November 29, 2010. https://wiki.linaro.org/WorkingGroups/KernelConsolidation/Meetings/2010-11-… == Summary == * Focusing on completing of the blueprints Definitions (Specifications). * Started the implementation phase of the blueprints. * Working on pushing patches upstream: * u-boot patches * PIO driver * 5500 flash related code * One Android patch submitted by John was accepted into -tip * Thumb2 SMP/Uniprocessor runtime switch on Versatile Express, also on multiple ARM platforms with single kernel. * Fixed and opened bugs * Fixed two Linaro bugs on iMX51 uboot * opened a bug against toolchain code sourcery. * Packaged a kernel, 2.6.37-rc3 made all the Ubuntu sauce apply cleanly!!! packaged kernel will be done every few weeks in general. Loic does non-packaged nightly kernel builds for more frequent testing. * Working on definition document on what the Linaro tree really is: what is accepted, what it can be used for, what it really is. People seem to be getting more comfortable with the Linaro tree. Regards, Mounir

14 years

Re: [PATCH][ ARM cpu hotplug 1/2 ] extract common code for arm cpu hotplug

by Vincent Guittot

The goal of this patch is to remove as much duplicated code as possible in each platform hotplug file. I have also tried to keep in mind that current platform upstreamed code make nearly no power management in their current implementation. I have added a new interface and a new file in order to -Keep the current interface as it is. So each platform could move to common code when they want -Have a dedicated file for arm hotplug function in which we can add all code that must be executed on an arm core whatever the platform (flushing cache, SCU disabling and handling spurious wake up as a staring point). I agree that the current code is quite small for now and we can wonder if a dedicated file is useful, code might be put in kernel/smp.c file. The next step is also to add some hotplug tracepoints and I would prefer to add the tracepoints only in a platform independent code. With the common code, a new arm platform can have the hotplug feature with less than 20 lines (power management not included) and can be sure that minimal actions will be handled by the common Arm code. We can also keep the platform_cpu_die has the platform entry point and move the common part into kernel/smp.c file. We still have few duplicated code (spurious wake-up) but this seems to be acceptable. I have taken your example into account and have updated the patch accordingly Vincent On 29 November 2010 11:41, Russell King - ARM Linux <linux(a)arm.linux.org.uk> wrote: > On Mon, Nov 29, 2010 at 10:54:35AM +0100, Vincent Guittot wrote: >> This patch extracts the common code of the cpu hotplug feature across >> arm platforms. The goal is to only keep the specific stuff of the >> platform in the sub-architecture. I have created a hotplug.c file in >> the arm/common directory after studying the cpu hotplug code of >> omap2, realview, s5pv310, ux500 and tegra. I have extracted 3 main >> platform dependent functions: >> -platform_enter_lowpower which prepares the platform for low power. >> -platform_do_lowpower on which the cpu will loop until it becomes >> really plugged (spurious wake up). This function must returned the cpu >> Id in order to leave the unplug state. >> -platform_leave_lowpower which restore the platform context. > > I still do not like this patch. The only thing that is worth doing is > this. This leaves less than 256 bytes of object code in the Realview > hotplug.c, most of which is the stuff to handle the low power mode > which you haven't dealt with in your patch either. > > I see no point in adding another API on top of the already existing > and simple API. > Signed-off-by: Vincent Guittot <vincent.guittot(a)linaro.org> --- arch/arm/kernel/smp.c | 35 ++++++++++++++++++++---- arch/arm/mach-omap2/omap-hotplug.c | 28 ------------------- arch/arm/mach-realview/hotplug.c | 29 -------------------- arch/arm/mach-s5pv310/hotplug.c | 29 -------------------- arch/arm/mach-tegra/hotplug.c | 30 --------------------- arch/arm/mach-ux500/hotplug.c | 51 +++++------------------------------- 6 files changed, 36 insertions(+), 166 deletions(-) diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c index 8c19595..03042db 100644 --- a/arch/arm/kernel/smp.c +++ b/arch/arm/kernel/smp.c @@ -24,6 +24,7 @@ #include <linux/irq.h> #include <linux/percpu.h> #include <linux/clockchips.h> +#include <linux/completion.h> #include <asm/atomic.h> #include <asm/cacheflush.h> @@ -213,11 +214,13 @@ int __cpu_disable(void) { unsigned int cpu = smp_processor_id(); struct task_struct *p; - int ret; - ret = platform_cpu_disable(cpu); - if (ret) - return ret; + /* + * we don't allow CPU 0 to be shutdown (it is still too special + * e.g. clock tick interrupts) + */ + if (cpu == 0) + return -EPERM; /* * Take this CPU offline. Once we clear this, we can't return, @@ -252,14 +255,16 @@ int __cpu_disable(void) return 0; } +static DECLARE_COMPLETION(cpu_killed); + /* * called on the thread which is asking for a CPU to be shutdown - * waits until shutdown has completed, or it is timed out. */ void __cpu_die(unsigned int cpu) { - if (!platform_cpu_kill(cpu)) - printk("CPU%u: unable to kill\n", cpu); + if (!wait_for_completion_timeout(&cpu_killed, 5000)) + printk(KERN_NOTICE "CPU%u: cpu didn't die\n", cpu); } /* @@ -273,14 +278,32 @@ void __cpu_die(unsigned int cpu) void __ref cpu_die(void) { unsigned int cpu = smp_processor_id(); +#ifdef DEBUG + unsigned int this_cpu = hard_smp_processor_id(); +#endif local_irq_disable(); idle_task_exit(); + printk(KERN_NOTICE "CPU%u: shutdown\n", cpu); + complete(&cpu_killed); + +#ifdef DEBUG + if (cpu != this_cpu) { + printk(KERN_CRIT "Eek! platform_cpu_die is going to run on %u, should be %u\n", + this_cpu, cpu); + BUG(); + } +#endif + + flush_cache_all(); + wmb(); + /* * actual CPU shutdown procedure is at least platform (if not * CPU) specific */ + platform_cpu_die(cpu); /* diff --git a/arch/arm/mach-omap2/omap-hotplug.c b/arch/arm/mach-omap2/omap-hotplug.c index 6cee456..00f4190 100644 --- a/arch/arm/mach-omap2/omap-hotplug.c +++ b/arch/arm/mach-omap2/omap-hotplug.c @@ -17,35 +17,15 @@ #include <linux/kernel.h> #include <linux/errno.h> #include <linux/smp.h> -#include <linux/completion.h> -#include <asm/cacheflush.h> #include <mach/omap4-common.h> -static DECLARE_COMPLETION(cpu_killed); - -int platform_cpu_kill(unsigned int cpu) -{ - return wait_for_completion_timeout(&cpu_killed, 5000); -} - /* * platform-specific code to shutdown a CPU * Called with IRQs disabled */ void platform_cpu_die(unsigned int cpu) { - unsigned int this_cpu = hard_smp_processor_id(); - - if (cpu != this_cpu) { - pr_crit("platform_cpu_die running on %u, should be %u\n", - this_cpu, cpu); - BUG(); - } - pr_notice("CPU%u: shutdown\n", cpu); - complete(&cpu_killed); - flush_cache_all(); - dsb(); /* * we're ready for shutdown now, so do it @@ -69,11 +49,3 @@ void platform_cpu_die(unsigned int cpu) } } -int platform_cpu_disable(unsigned int cpu) -{ - /* - * we don't allow CPU 0 to be shutdown (it is still too special - * e.g. clock tick interrupts) - */ - return cpu == 0 ? -EPERM : 0; -} diff --git a/arch/arm/mach-realview/hotplug.c b/arch/arm/mach-realview/hotplug.c index f95521a..580cf7c 100644 --- a/arch/arm/mach-realview/hotplug.c +++ b/arch/arm/mach-realview/hotplug.c @@ -11,19 +11,16 @@ #include <linux/kernel.h> #include <linux/errno.h> #include <linux/smp.h> -#include <linux/completion.h> #include <asm/cacheflush.h> extern volatile int pen_release; -static DECLARE_COMPLETION(cpu_killed); static inline void cpu_enter_lowpower(void) { unsigned int v; - flush_cache_all(); asm volatile( " mcr p15, 0, %1, c7, c5, 0\n" " mcr p15, 0, %1, c7, c10, 4\n" @@ -93,11 +90,6 @@ static inline void platform_do_lowpower(unsigned int cpu) } } -int platform_cpu_kill(unsigned int cpu) -{ - return wait_for_completion_timeout(&cpu_killed, 5000); -} - /* * platform-specific code to shutdown a CPU * @@ -105,18 +97,6 @@ int platform_cpu_kill(unsigned int cpu) */ void platform_cpu_die(unsigned int cpu) { -#ifdef DEBUG - unsigned int this_cpu = hard_smp_processor_id(); - - if (cpu != this_cpu) { - printk(KERN_CRIT "Eek! platform_cpu_die running on %u, should be %u\n", - this_cpu, cpu); - BUG(); - } -#endif - - printk(KERN_NOTICE "CPU%u: shutdown\n", cpu); - complete(&cpu_killed); /* * we're ready for shutdown now, so do it @@ -130,12 +110,3 @@ void platform_cpu_die(unsigned int cpu) */ cpu_leave_lowpower(); } - -int platform_cpu_disable(unsigned int cpu) -{ - /* - * we don't allow CPU 0 to be shutdown (it is still too special - * e.g. clock tick interrupts) - */ - return cpu == 0 ? -EPERM : 0; -} diff --git a/arch/arm/mach-s5pv310/hotplug.c b/arch/arm/mach-s5pv310/hotplug.c index 03652c3..59eafad 100644 --- a/arch/arm/mach-s5pv310/hotplug.c +++ b/arch/arm/mach-s5pv310/hotplug.c @@ -13,19 +13,16 @@ #include <linux/kernel.h> #include <linux/errno.h> #include <linux/smp.h> -#include <linux/completion.h> #include <asm/cacheflush.h> extern volatile int pen_release; -static DECLARE_COMPLETION(cpu_killed); static inline void cpu_enter_lowpower(void) { unsigned int v; - flush_cache_all(); asm volatile( " mcr p15, 0, %1, c7, c5, 0\n" " mcr p15, 0, %1, c7, c10, 4\n" @@ -96,11 +93,6 @@ static inline void platform_do_lowpower(unsigned int cpu) } } -int platform_cpu_kill(unsigned int cpu) -{ - return wait_for_completion_timeout(&cpu_killed, 5000); -} - /* * platform-specific code to shutdown a CPU * @@ -108,19 +100,6 @@ int platform_cpu_kill(unsigned int cpu) */ void platform_cpu_die(unsigned int cpu) { -#ifdef DEBUG - unsigned int this_cpu = hard_smp_processor_id(); - - if (cpu != this_cpu) { - printk(KERN_CRIT "Eek! platform_cpu_die running on %u, should be %u\n", - this_cpu, cpu); - BUG(); - } -#endif - - printk(KERN_NOTICE "CPU%u: shutdown\n", cpu); - complete(&cpu_killed); - /* * we're ready for shutdown now, so do it */ @@ -134,11 +113,3 @@ void platform_cpu_die(unsigned int cpu) cpu_leave_lowpower(); } -int platform_cpu_disable(unsigned int cpu) -{ - /* - * we don't allow CPU 0 to be shutdown (it is still too special - * e.g. clock tick interrupts) - */ - return cpu == 0 ? -EPERM : 0; -} diff --git a/arch/arm/mach-tegra/hotplug.c b/arch/arm/mach-tegra/hotplug.c index 8e7f115..7e5eb3d 100644 --- a/arch/arm/mach-tegra/hotplug.c +++ b/arch/arm/mach-tegra/hotplug.c @@ -11,17 +11,14 @@ #include <linux/kernel.h> #include <linux/errno.h> #include <linux/smp.h> -#include <linux/completion.h> #include <asm/cacheflush.h> -static DECLARE_COMPLETION(cpu_killed); static inline void cpu_enter_lowpower(void) { unsigned int v; - flush_cache_all(); asm volatile( " mcr p15, 0, %1, c7, c5, 0\n" " mcr p15, 0, %1, c7, c10, 4\n" @@ -92,11 +89,6 @@ static inline void platform_do_lowpower(unsigned int cpu) } } -int platform_cpu_kill(unsigned int cpu) -{ - return wait_for_completion_timeout(&cpu_killed, 5000); -} - /* * platform-specific code to shutdown a CPU * @@ -104,19 +96,6 @@ int platform_cpu_kill(unsigned int cpu) */ void platform_cpu_die(unsigned int cpu) { -#ifdef DEBUG - unsigned int this_cpu = hard_smp_processor_id(); - - if (cpu != this_cpu) { - printk(KERN_CRIT "Eek! platform_cpu_die running on %u, should be %u\n", - this_cpu, cpu); - BUG(); - } -#endif - - printk(KERN_NOTICE "CPU%u: shutdown\n", cpu); - complete(&cpu_killed); - /* * we're ready for shutdown now, so do it */ @@ -129,12 +108,3 @@ void platform_cpu_die(unsigned int cpu) */ cpu_leave_lowpower(); } - -int platform_cpu_disable(unsigned int cpu) -{ - /* - * we don't allow CPU 0 to be shutdown (it is still too special - * e.g. clock tick interrupts) - */ - return cpu == 0 ? -EPERM : 0; -} diff --git a/arch/arm/mach-ux500/hotplug.c b/arch/arm/mach-ux500/hotplug.c index b782a03..37b443b 100644 --- a/arch/arm/mach-ux500/hotplug.c +++ b/arch/arm/mach-ux500/hotplug.c @@ -6,23 +6,22 @@ * Based on ARM realview platform * * Author: Sundar Iyer <sundar.iyer(a)stericsson.com> + * Author: vincent.guittot <vincent.guittot(a)stericsson.com> * */ #include <linux/kernel.h> #include <linux/errno.h> #include <linux/smp.h> -#include <linux/completion.h> - -#include <asm/cacheflush.h> extern volatile int pen_release; -static DECLARE_COMPLETION(cpu_killed); - -static inline void platform_do_lowpower(unsigned int cpu) +/* + * platform-specific code to shutdown a CPU + * + * Called with IRQs disabled + */ +void platform_cpu_die(unsigned int cpu) { - flush_cache_all(); - /* we put the platform to just WFI */ for (;;) { __asm__ __volatile__("dsb\n\t" "wfi\n\t" @@ -36,40 +35,4 @@ static inline void platform_do_lowpower(unsigned int cpu) } } -int platform_cpu_kill(unsigned int cpu) -{ - return wait_for_completion_timeout(&cpu_killed, 5000); -} - -/* - * platform-specific code to shutdown a CPU - * - * Called with IRQs disabled - */ -void platform_cpu_die(unsigned int cpu) -{ -#ifdef DEBUG - unsigned int this_cpu = hard_smp_processor_id(); - - if (cpu != this_cpu) { - printk(KERN_CRIT "Eek! platform_cpu_die running on %u, should be %u\n", - this_cpu, cpu); - BUG(); - } -#endif - - printk(KERN_NOTICE "CPU%u: shutdown\n", cpu); - complete(&cpu_killed); - - /* directly enter low power state, skipping secure registers */ - platform_do_lowpower(cpu); -} -int platform_cpu_disable(unsigned int cpu) -{ - /* - * we don't allow CPU 0 to be shutdown (it is still too special - * e.g. clock tick interrupts) - */ - return cpu == 0 ? -EPERM : 0; -} -- 1.7.0.4

14 years

NEON power consumption

by Michael Hope

I sat down and measured the power consumption of the NEON unit on an OMAP3. Method and results are here: https://wiki.linaro.org/MichaelHope/Sandbox/NEONPower The board takes 2.37 W and the NEON unit adds an extra 120 mW. Assuming the core takes 1 W, then the code needs to run 12 % faster with NEON on to be a net power win. Note that the results are inaccurate but valid enough. -- Michael

14 years

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linaro-dev November 2010