kernel.git/arch/powerpc/platforms/pseries/setup.c, branch linux-3.10.y

powerpc: Default arch idle could cede processor on pseries

2013-09-27T00:18:01Z

commit 363edbe2614aa90df706c0f19ccfa2a6c06af0be upstream. When adding cpuidle support to pSeries, we introduced two regressions: - The new cpuidle backend driver only works under hypervisors supporting the "SLPLAR" option, which isn't the case of the old POWER4 hypervisor and the HV "light" used on js2x blades - The cpuidle driver registers fairly late, meaning that for a significant portion of the boot process, we end up having all threads spinning. This slows down the boot process and increases the overall resource usage if the hypervisor has shared processors. This fixes both by implementing a "default" idle that will cede to the hypervisor when possible, in a very simple way without all the bells and whisles of cpuidle. Reported-by: Paul Mackerras Signed-off-by: Vaidyanathan Srinivasan Acked-by: Deepthi Dharwar Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Greg Kroah-Hartman

powerpc/pseries: Perform proper max_bus_speed detection

2013-05-05T23:25:38Z

On pseries machines the detection for max_bus_speed should be done through an OpenFirmware property. This patch adds a function to perform this detection and a hook to perform dynamic adding of the function only for pseries. This is done by overwriting the weak pcibios_root_bridge_prepare function which is called by pci_create_root_bus(). From: Lucas Kannebley Tavares Signed-off-by: Kleber Sacilotto de Souza Signed-off-by: Benjamin Herrenschmidt

powerpc/pseries: Update firmware_has_feature() to check architecture vector 5 bits

2013-04-26T06:08:22Z

The firmware_has_feature() function makes it easy to check for supported features of the hypervisor. This patch extends the capability of firmware_has_feature() to include checking for specified bits in vector 5 of the architecture vector as reported in the device tree. As part of this the #defines used for the architecture vector are re-defined such that each option has the index into vector 5 and the feature bit encoded into it. This makes checking for architecture bits when initiating data for firmware_has_feature much easier. Signed-off-by: Nathan Fontenot Signed-off-by: Benjamin Herrenschmidt

Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc

2013-02-24T01:09:55Z

Pull powerpc updates from Benjamin Herrenschmidt: "So from the depth of frozen Minnesota, here's the powerpc pull request for 3.9. It has a few interesting highlights, in addition to the usual bunch of bug fixes, minor updates, embedded device tree updates and new boards: - Hand tuned asm implementation of SHA1 (by Paulus & Michael Ellerman) - Support for Doorbell interrupts on Power8 (kind of fast thread-thread IPIs) by Ian Munsie - Long overdue cleanup of the way we handle relocation of our open firmware trampoline (prom_init.c) on 64-bit by Anton Blanchard - Support for saving/restoring & context switching the PPR (Processor Priority Register) on server processors that support it. This allows the kernel to preserve thread priorities established by userspace. By Haren Myneni. - DAWR (new watchpoint facility) support on Power8 by Michael Neuling - Ability to change the DSCR (Data Stream Control Register) which controls cache prefetching on a running process via ptrace by Alexey Kardashevskiy - Support for context switching the TAR register on Power8 (new branch target register meant to be used by some new specific userspace perf event interrupt facility which is yet to be enabled) by Ian Munsie. - Improve preservation of the CFAR register (which captures the origin of a branch) on various exception conditions by Paulus. - Move the Bestcomm DMA driver from arch powerpc to drivers/dma where it belongs by Philippe De Muyter - Support for Transactional Memory on Power8 by Michael Neuling (based on original work by Matt Evans). For those curious about the feature, the patch contains a pretty good description." (See commit db8ff907027b: "powerpc: Documentation for transactional memory on powerpc" for the mentioned description added to the file Documentation/powerpc/transactional_memory.txt) * 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (140 commits) powerpc/kexec: Disable hard IRQ before kexec powerpc/85xx: l2sram - Add compatible string for BSC9131 platform powerpc/85xx: bsc9131 - Correct typo in SDHC device node powerpc/e500/qemu-e500: enable coreint powerpc/mpic: allow coreint to be determined by MPIC version powerpc/fsl_pci: Store the pci ctlr device ptr in the pci ctlr struct powerpc/85xx: Board support for ppa8548 powerpc/fsl: remove extraneous DIU platform functions arch/powerpc/platforms/85xx/p1022_ds.c: adjust duplicate test powerpc: Documentation for transactional memory on powerpc powerpc: Add transactional memory to pseries and ppc64 defconfigs powerpc: Add config option for transactional memory powerpc: Add transactional memory to POWER8 cpu features powerpc: Add new transactional memory state to the signal context powerpc: Hook in new transactional memory code powerpc: Routines for FP/VSX/VMX unavailable during a transaction powerpc: Add transactional memory unavaliable execption handler powerpc: Add reclaim and recheckpoint functions for context switching transactional memory processes powerpc: Add FP/VSX and VMX register load functions for transactional memory powerpc: Add helper functions for transactional memory context switching ...

cputime: Generic on-demand virtual cputime accounting

2013-01-27T18:23:27Z

If we want to stop the tick further idle, we need to be able to account the cputime without using the tick. Virtual based cputime accounting solves that problem by hooking into kernel/user boundaries. However implementing CONFIG_VIRT_CPU_ACCOUNTING require low level hooks and involves more overhead. But we already have a generic context tracking subsystem that is required for RCU needs by archs which plan to shut down the tick outside idle. This patch implements a generic virtual based cputime accounting that relies on these generic kernel/user hooks. There are some upsides of doing this: - This requires no arch code to implement CONFIG_VIRT_CPU_ACCOUNTING if context tracking is already built (already necessary for RCU in full tickless mode). - We can rely on the generic context tracking subsystem to dynamically (de)activate the hooks, so that we can switch anytime between virtual and tick based accounting. This way we don't have the overhead of the virtual accounting when the tick is running periodically. And one downside: - There is probably more overhead than a native virtual based cputime accounting. But this relies on hooks that are already set anyway. Signed-off-by: Frederic Weisbecker Cc: Andrew Morton Cc: Ingo Molnar Cc: Li Zhong Cc: Namhyung Kim Cc: Paul E. McKenney Cc: Paul Gortmaker Cc: Peter Zijlstra Cc: Steven Rostedt Cc: Thomas Gleixner

powerpc: Add the DAWR support to the set_break()

2013-01-10T06:01:47Z

This adds DAWR supoprt to the set_break(). It does both bare metal and PAPR versions of setting the DAWR. There is still some work we can do to make full use of the watchpoint but that will come later. Signed-off-by: Michael Neuling Signed-off-by: Benjamin Herrenschmidt

powerpc: Disable relocation on exceptions whenever PR KVM is active

2013-01-10T06:00:42Z

For PR KVM we allow userspace to map 0xc000000000000000. Because transitioning from userspace to the guest kernel may use the relocated exception vectors we have to disable relocation on exceptions whenever PR KVM is active as we cannot trust that address. This issue does not apply to HV KVM, since changing from a guest to the hypervisor will never use the relocated exception vectors. Currently the hypervisor interface only allows us to toggle relocation on exceptions on a partition wide scope, so we need to globally disable relocation on exceptions when the first PR KVM instance is started and only re-enable them when all PR KVM instances have been destroyed. It's a bit heavy handed, but until the hypervisor gives us a lightweight way to toggle relocation on exceptions on a single thread it's only real option. Signed-off-by: Ian Munsie Signed-off-by: Benjamin Herrenschmidt

powerpc: Disable relocation on exceptions when kexecing

2012-11-15T04:08:08Z

Since we don't know if they new kernel we are kexecing into has been built to support relocation on exceptions, we disable them before we kexec. We do NOT disable them if we are execing a kdump kernel, because we want to change as little state as possible and it is likely that we are execing ourselves and will be able to handle them anyway. Signed-off-by: Ian Munsie Signed-off-by: Michael Neuling Signed-off-by: Benjamin Herrenschmidt

powerpc: Enable relocation on during exceptions at boot

2012-11-15T04:08:08Z

We currently do this synchronously at boot from setup_arch. On a large system this could hypothetically take a little while to complete, so currently we will give up if we are asked to wait for more than a second in total. If we actually start hitting that timeout in practice we can always move this code into a kernel thread to take care of it in the background. Signed-off-by: Ian Munsie Signed-off-by: Michael Neuling Signed-off-by: Benjamin Herrenschmidt

powerpc+of: Add of node/property notification chain for adds and removes

2012-11-15T01:56:41Z

This patch moves the notification chain for updates to the device tree from the powerpc/pseries code to the base OF code. This makes this functionality available to all architectures. Additionally the notification chain is updated to allow notifications for property add/remove/update. To make this work a pointer to a new struct (of_prop_reconfig) is passed to the routines in the notification chain. The of_prop_reconfig property contains a pointer to the node containing the property and a pointer to the property itself. In the case of property updates, the property pointer refers to the new property. Signed-off-by: Nathan Fontenot Acked-by: Rob Herring Acked-by: Grant Likely Signed-off-by: Benjamin Herrenschmidt