This patch does following optimizations: 1. Pre-compute hart base for each context handler 2. Pre-compute enable base for each context handler 3. Have enable lock for each context handler instead of global plic_toggle_lock
Signed-off-by: Anup Patel <a...@brainfault.org> --- drivers/irqchip/irq-sifive-plic.c | 47 ++++++++++++++----------------- 1 file changed, 21 insertions(+), 26 deletions(-) diff --git a/drivers/irqchip/irq-sifive-plic.c b/drivers/irqchip/irq-sifive-plic.c index 357e9daf94ae..c23a293a2aae 100644 --- a/drivers/irqchip/irq-sifive-plic.c +++ b/drivers/irqchip/irq-sifive-plic.c @@ -59,37 +59,28 @@ static void __iomem *plic_regs; struct plic_handler { bool present; - int ctxid; + void __iomem *hart_base; + /* + * Protect mask operations on the registers given that we can't + * assume atomic memory operations work on them. + */ + raw_spinlock_t enable_lock; + void __iomem *enable_base; }; static DEFINE_PER_CPU(struct plic_handler, plic_handlers); -static inline void __iomem *plic_hart_offset(int ctxid) -{ - return plic_regs + CONTEXT_BASE + ctxid * CONTEXT_PER_HART; -} - -static inline u32 __iomem *plic_enable_base(int ctxid) -{ - return plic_regs + ENABLE_BASE + ctxid * ENABLE_PER_HART; -} - -/* - * Protect mask operations on the registers given that we can't assume that - * atomic memory operations work on them. - */ -static DEFINE_RAW_SPINLOCK(plic_toggle_lock); - -static inline void plic_toggle(int ctxid, int hwirq, int enable) +static inline void plic_toggle(struct plic_handler *handler, + int hwirq, int enable) { - u32 __iomem *reg = plic_enable_base(ctxid) + (hwirq / 32); + u32 __iomem *reg = handler->enable_base + (hwirq / 32) * sizeof(u32); u32 hwirq_mask = 1 << (hwirq % 32); - raw_spin_lock(&plic_toggle_lock); + raw_spin_lock(&handler->enable_lock); if (enable) writel(readl(reg) | hwirq_mask, reg); else writel(readl(reg) & ~hwirq_mask, reg); - raw_spin_unlock(&plic_toggle_lock); + raw_spin_unlock(&handler->enable_lock); } static inline void plic_irq_toggle(struct irq_data *d, int enable) @@ -101,7 +92,7 @@ static inline void plic_irq_toggle(struct irq_data *d, int enable) struct plic_handler *handler = per_cpu_ptr(&plic_handlers, cpu); if (handler->present) - plic_toggle(handler->ctxid, d->hwirq, enable); + plic_toggle(handler, d->hwirq, enable); } } @@ -150,7 +141,7 @@ static struct irq_domain *plic_irqdomain; static void plic_handle_irq(struct pt_regs *regs) { struct plic_handler *handler = this_cpu_ptr(&plic_handlers); - void __iomem *claim = plic_hart_offset(handler->ctxid) + CONTEXT_CLAIM; + void __iomem *claim = handler->hart_base + CONTEXT_CLAIM; irq_hw_number_t hwirq; WARN_ON_ONCE(!handler->present); @@ -239,12 +230,16 @@ static int __init plic_init(struct device_node *node, cpu = riscv_hartid_to_cpuid(hartid); handler = per_cpu_ptr(&plic_handlers, cpu); handler->present = true; - handler->ctxid = i; + handler->hart_base = + plic_regs + CONTEXT_BASE + i * CONTEXT_PER_HART; + raw_spin_lock_init(&handler->enable_lock); + handler->enable_base = + plic_regs + ENABLE_BASE + i * ENABLE_PER_HART; /* priority must be > threshold to trigger an interrupt */ - writel(0, plic_hart_offset(i) + CONTEXT_THRESHOLD); + writel(0, handler->hart_base + CONTEXT_THRESHOLD); for (hwirq = 1; hwirq <= nr_irqs; hwirq++) - plic_toggle(i, hwirq, 0); + plic_toggle(handler, hwirq, 0); nr_mapped++; } -- 2.17.1