2013-04-18 14:14:42

by Gerlando Falauto

[permalink] [raw]
Subject: Re: [PATCH v3b 0/9] refactoring for mask_cache

Hi everyone,

any chance we could move this pachset to the next level (at least for

Thanks a lot!

On 03/21/2013 06:12 PM, Gerlando Falauto wrote:
> This patchset addresses a regression found with the Orion GPIO controller
> when both Edge- and Level- based interrupts are requested within the same
> GPIO chip. The regression was introduced by e59347a
> "arm: orion: Use generic irq chip"
> thereby affecting all kernel releases since 3.0.x.
> The reason behind it is that the Orion GPIO controller uses separate
> mask registers for the two types of interrupts (one for edge and one
> for level), whereas in other cases the same register would be shared.
> Since this mask register is cached, we need to have (potentially)
> separate register caches.
> We do that by adding a per-chip-type mask register cache, and a mask cache
> pointer (which will point either to that or the shared one).
> So we proceed with incremental stages:
> a) we introduce the new fields and pointer (though only the shared one is used)
> b) we convert all drivers to use it
> c) we rename the field so to force the use of the per-ct pointer
> d) we add per-ct mask cache, provided the new flag
> e) we enable the flag for orion-gpio and mvebu drivers
> The changes were tested by Simon Guinot to be effective on Kirkwood chipsets,
> on both the legacy orion-gpio and the new gpio-mvebu drivers.
> The bug should also affect the other two Marvell variants handled by
> the gpio-mvebu driver.
> Changes from v3: cover letter and SOB lines.
> Gerlando Falauto (9):
> genirq: cosmetic: remove cur_regs
> genirq: add mask_cache and pmask_cache into struct irq_chip_type
> gpio: mvebu: convert to usage of *pmask_cache within irq_chip_type
> MIPS: JZ4740: convert to usage of *pmask_cache within irq_chip_type
> ARM: SAMSUNG: convert to usage of *pmask_cache within irq_chip_type
> genirq: rename mask_cache to shared_mask_cache
> genirq: handle separate mask registers
> gpio: mvebu: enable IRQ_GC_SEPARATE_MASK_REGISTERS
> arch/arm/plat-orion/gpio.c | 3 +-
> arch/arm/plat-samsung/irq-vic-timer.c | 6 ++--
> arch/mips/jz4740/irq.c | 3 +-
> drivers/gpio/gpio-mvebu.c | 23 ++++++++------
> include/linux/irq.h | 9 ++++--
> kernel/irq/generic-chip.c | 55 +++++++++++++++++++++------------
> 6 files changed, 64 insertions(+), 35 deletions(-)