Messages in this thread | | | Date | Thu, 2 Aug 2018 12:04:04 +0200 (CEST) | From | Thomas Gleixner <> | Subject | Re: [PATCH 7/9] irqchip: add a RISC-V PLIC driver |
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On Thu, 26 Jul 2018, Christoph Hellwig wrote:
> This patch adds a driver for the Platform Level Interrupt Controller (PLIC)
See Documentation/process/submitting-patches.rst and search for 'This patch'
> +static inline void __iomem *plic_hart_offset(int ctxid) > +{ > + return plic_regs + CONTEXT_BASE + ctxid * CONTEXT_PER_HART; > +} > + > +/* > + * Protect mask operations on the registers given that we can't assume that > + * atomic memory operations work on them. > + */ > +static DEFINE_SPINLOCK(plic_toggle_lock);
RAW_SPINLOCK please.
> + > +static inline void plic_toggle(int ctxid, int hwirq, int enable) > +{ > + u32 __iomem *reg = plic_regs + ENABLE_BASE + ctxid * ENABLE_PER_HART; > + u32 hwirq_mask = 1 << (hwirq % 32); > + > + spin_lock(&plic_toggle_lock); > + if (enable) > + writel(readl(reg) | hwirq_mask, reg); > + else > + writel(readl(reg) & ~hwirq_mask, reg); > + spin_unlock(&plic_toggle_lock); > +} > + > +static inline void plic_irq_toggle(struct irq_data *d, int enable) > +{ > + int cpu; > + > + writel(enable, plic_regs + PRIORITY_BASE + d->hwirq * PRIORITY_PER_ID); > + for_each_present_cpu(cpu) > + plic_toggle(cpu, d->hwirq, enable);
I suggest to make that:
for_each_cpu(cpu, irq_data_get_affinity_mask(d)) plic_toggle(cpu, d->hwirq, enable);
That gives you immediately support for interrupt affinity. And then it's trivial to do the actual irq_chip::irq_set_affinity() magic as well.
> +/* > + * Handling an interrupt is a two-step process: first you claim the interrupt > + * by reading the claim register, then you complete the interrupt by writing > + * that source ID back to the same claim register. This automatically enables > + * and disables the interrupt, so there's nothing else to do. > + */ > +static void plic_handle_irq(struct pt_regs *regs) > +{ > + void __iomem *claim = > + plic_hart_offset(smp_processor_id()) + CONTEXT_CLAIM;
Either ignore the 80 char thing or just move the assignment into the code section please. That line break is horrible to read.
> + irq_hw_number_t hwirq; > +
Other than that this looks halfways sane.
Thanks,
tglx
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