From mboxrd@z Thu Jan 1 00:00:00 1970 From: marc.zyngier@arm.com (Marc Zyngier) Date: Wed, 06 Jul 2011 12:02:26 +0100 Subject: [PATCH v8 00/14] Consolidating GIC per-cpu interrupts In-Reply-To: <1309855755-6261-1-git-send-email-marc.zyngier@arm.com> References: <1309855755-6261-1-git-send-email-marc.zyngier@arm.com> Message-ID: <4E1440C2.2000203@arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 05/07/11 09:49, Marc Zyngier wrote: > The current GIC per-cpu interrupts (aka PPIs) suffer from a number of > problems: > > - They use a completely separate scheme to handle the interrupts, > mostly because the PPI concept doesn't really match the kernel view > of an interrupt. > - PPIs can only be used by the timer code, unless we add more low-level > assembly code. > - The local timer code can only be used by devices generating PPIs, > and not SPIs. > - At least one platform (msm) has started implementing its own > alternative scheme. > - Some low-level code gets duplicated, as usual... > > The proposed solution is to let the GIC code expose the PPIs as > something that the kernel can manage. Instead of having a single > interrupt number shared on all cores, make the interrupt number be > different on each CPU. > > This enables the use of the normal kernel API (request_irq() and > friends) and the elimination of some low level code. It also serves as > the basis of the GIC device tree support code. On the other side, it > causes quite a bit of churn in the timer code. > > Previous versions of this series have received ACKs from some platform > maintainers, but so far there has been very little comment on the core > code. As I now have quite a large number of patches relying on this > series (local timers as devices, device tree support for GIC and TWD), > I'd be grateful for at least a hint indicating that this is going in > the right direction. Or not. > > This patch set is based on 3.0-rc5. Tested on PB-11MP, Tegra2 > (Harmony) and SMDK-V310. Also available in the "gic_ppi_map" branch of > git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms.git > > From v7: > - Rebased on v3.0-rc5 > - Rename gic_ppi_to_vppi() to gic_ppi_map() > - Rename CONFIG_ARM_GIC_VPPI to CONFIG_ARM_GIC_PPI_MAP > - Add gic_ppi_map_on_cpu() > > From v6: > - Fix compilation when !CONFIG_PM. > > From v5: > - Update Exynos4 MCT to use the local timer infrastructure, now that > it doesn't depend on PPIs anymore. Untested, as the board I have > doesn't implement MCT (EVT0 syndrome). > > From v4: > - Fix arch/arm/common/Kconfig indentation > - Fix MSM warning when building UP. > > From v3: > - Fix yet another CPU_HOTPLUG problem: instead of calling free_irq() > on timer halt, just disable the interrupt. On timer restart, detect > that the interrupt has been requested already and just enable the > interrupt back. This avoid doing a request_irq() with preemption > disabled, which triggers an ugly warning. Reported by Stephen Boyd. > > From v2: > - More MSM fixes > - Dropped MSM interrupt handler removal, as this requires more discussion, > and will be addressed in a separate series. > - Moved introduction of percpu_timer_handler to a separate patch > > From v1: > - Fix crash while hotpluging a CPU > - Use handle_percpu_irq() instead of handle_fasteoi_irq() > - MSM fixes courtesy of Stephen Boyd > - MSM switched to percpu_timer_handler() > - Remove local timer interrupt accounting > - Restructure patches #1 and #2 > > Marc Zyngier (14): > ARM: gic: add per-cpu interrupt mapping > ARM: smp: add interrupt handler for local timers > ARM: smp_twd: add support for remapped PPI interrupts > ARM: omap4: use remapped PPI interrupts for local timer > ARM: versatile: use remapped PPI interrupts for local timer > ARM: shmobile: use remapped PPI interrupts for local timer > ARM: ux500: use remapped PPI interrupts for local timer > ARM: tegra: use remapped PPI interrupts for local timer > ARM: msm: use remapped PPI interrupts for local timer > ARM: exynos4: use remapped PPI interrupts for local timer > ARM: gic: remove previous local timer interrupt handling > ARM: gic: add compute_irqnr macro for exynos4 > ARM: SMP: automatically select ARM_GIC_PPI_MAP > ARM: gic: add gic_ppi_map_on_cpu() > > arch/arm/Kconfig | 1 + > arch/arm/common/Kconfig | 5 + > arch/arm/common/gic.c | 152 +++++++++++++++++++-- > arch/arm/include/asm/entry-macro-multi.S | 7 - > arch/arm/include/asm/hardirq.h | 3 - > arch/arm/include/asm/hardware/entry-macro-gic.S | 31 ++--- > arch/arm/include/asm/hardware/gic.h | 11 ++- > arch/arm/include/asm/localtimer.h | 7 +- > arch/arm/include/asm/smp.h | 5 - > arch/arm/kernel/irq.c | 11 +- > arch/arm/kernel/smp.c | 27 +--- > arch/arm/kernel/smp_twd.c | 25 +++- > arch/arm/mach-exynos4/include/mach/entry-macro.S | 70 +--------- > arch/arm/mach-exynos4/localtimer.c | 3 +- > arch/arm/mach-msm/board-msm8x60.c | 11 -- > arch/arm/mach-msm/include/mach/entry-macro-qgic.S | 73 +---------- > arch/arm/mach-msm/timer.c | 58 ++++---- > arch/arm/mach-omap2/include/mach/entry-macro.S | 14 +-- > arch/arm/mach-omap2/timer-mpu.c | 3 +- > arch/arm/mach-shmobile/entry-intc.S | 3 - > arch/arm/mach-shmobile/include/mach/entry-macro.S | 3 - > arch/arm/mach-shmobile/localtimer.c | 3 +- > arch/arm/mach-tegra/localtimer.c | 3 +- > arch/arm/mach-ux500/localtimer.c | 3 +- > arch/arm/plat-versatile/localtimer.c | 3 +- > 25 files changed, 253 insertions(+), 282 deletions(-) Russell, Unless you have any objection, I'd like to push this to Arnd's arm-soc tree. Would that be OK with you? Thanks, M. -- Jazz is not dead. It just smells funny...