On Tue, Jan 25, 2011 at 11:22 PM, Santosh Shilimkar <santosh.shilimkar@xxxxxx> wrote: >> -----Original Message----- >> From: ccross@xxxxxxxxxx [mailto:ccross@xxxxxxxxxx] On Behalf Of >> Colin Cross >> Sent: Wednesday, January 26, 2011 2:25 AM >> To: Santosh Shilimkar >> Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; linux- >> omap@xxxxxxxxxxxxxxx; catalin.marinas@xxxxxxx; >> linux@xxxxxxxxxxxxxxxx; linus.ml.walleij@xxxxxxxxx; Russell King >> Subject: Re: [PATCH 1/5] ARM: gic: Add hooks for architecture >> specific extensions >> >> On Mon, Jan 24, 2011 at 7:03 PM, Colin Cross <ccross@xxxxxxxxxxx> >> wrote: >> > On Mon, Jan 24, 2011 at 12:51 AM, Santosh Shilimkar >> > <santosh.shilimkar@xxxxxx> wrote: >> >> Few architectures combine the GIC with an external interrupt >> controller. >> >> On such systems it may be necessary to update both the GIC >> registers >> >> and the external controller's registers to control IRQ behavior. >> >> >> >> This can be addressed in couple of possible methods. >> >> 1. Export common GIC routines along with 'struct irq_chip >> gic_chip' >> >> and allow architectures to have custom function by >> override. >> >> >> >> 2. Provide architecture specific function pointer hooks >> >> within GIC library and leave platforms to add the >> necessary >> >> code as part of these hooks. >> >> >> >> First one might be non-intrusive but have few shortcomings like >> arch needs >> >> to have there own custom gic library. Locks used should be common >> since it >> >> caters to same IRQs etc. Maintenance point of view also it leads >> to >> >> multiple file fixes. >> >> >> >> The second probably is cleaner and portable. It ensures that all >> the >> >> common GIC infrastructure is not touched and also provides archs >> to >> >> address their specific issue. >> > >> > This method would work for most of Tegra's needs, although we >> would >> > need gic_set_type and gic_ack_irq to have arch extensions as well. >> > However, it does not allow for irq_retrigger, which can be >> implemented >> > on Tegra. >> >> irq_retrigger does work with this method, the core IRQ code checks >> for >> a return value if the retrigger was successful. Tegra works with >> your >> patch along with these changes: >> > Great. > Can I fold below changes in my patch and add you ack and tested-by? Sure >> diff --git a/arch/arm/common/gic.c b/arch/arm/common/gic.c >> index 0b6c043..7993f07 100644 >> --- a/arch/arm/common/gic.c >> +++ b/arch/arm/common/gic.c >> @@ -90,6 +90,8 @@ static inline unsigned int gic_irq(struct irq_data >> *d) >> static void gic_ack_irq(struct irq_data *d) >> { >> spin_lock(&irq_controller_lock); >> + if (gic_arch_extn.irq_ack) >> + gic_arch_extn.irq_ack(d); >> writel(gic_irq(d), gic_cpu_base(d) + GIC_CPU_EOI); >> spin_unlock(&irq_controller_lock); >> } >> @@ -161,6 +163,14 @@ static int gic_set_type(struct irq_data *d, >> unsigned int type) >> return 0; >> } >> >> +static int gic_retrigger(struct irq_data *d) >> +{ >> + if (gic_arch_extn.irq_retrigger) >> + return gic_arch_extn.irq_retrigger(d); >> + >> + return 0; >> +} >> + >> #ifdef CONFIG_SMP >> static int >> gic_set_cpu(struct irq_data *d, const struct cpumask *mask_val, >> bool force) >> @@ -234,6 +244,7 @@ static struct irq_chip gic_chip = { >> .irq_mask = gic_mask_irq, >> .irq_unmask = gic_unmask_irq, >> .irq_set_type = gic_set_type, >> + .irq_retrigger = gic_retrigger, >> #ifdef CONFIG_SMP >> .irq_set_affinity = gic_set_cpu, >> #endif > -- 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
