From e1b88ca8d72193e48bac026b19b8c686cc7fea25 Mon Sep 17 00:00:00 2001 From: Huacai Chen Date: Thu, 22 Jun 2017 23:06:52 +0800 Subject: [PATCH] MIPS: Loongson-3: IRQ balancing for PCI devices IRQ0 (HPET), IRQ1 (Keyboard), IRQ2 (Cascade), IRQ7 (SCI), IRQ8 (RTC) and IRQ12 (Mouse) are handled by core-0 locally. Other PCI IRQs (3, 4, 5, 6, 14, 15) are balanced by all cores from Node-0. This can improve I/O performance significantly. Signed-off-by: Huacai Chen Cc: John Crispin Cc: Steven J . Hill Cc: Fuxin Zhang Cc: Zhangjin Wu Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/16589/ Signed-off-by: Ralf Baechle --- arch/mips/loongson64/loongson-3/irq.c | 19 +++++++++++++++++-- arch/mips/loongson64/loongson-3/smp.c | 18 +++++++++++++++++- 2 files changed, 34 insertions(+), 3 deletions(-) diff --git a/arch/mips/loongson64/loongson-3/irq.c b/arch/mips/loongson64/loongson-3/irq.c index 548f759454dce..2e6e205ed9b9e 100644 --- a/arch/mips/loongson64/loongson-3/irq.c +++ b/arch/mips/loongson64/loongson-3/irq.c @@ -9,17 +9,32 @@ #include "smp.h" +extern void loongson3_send_irq_by_ipi(int cpu, int irqs); unsigned int ht_irq[] = {0, 1, 3, 4, 5, 6, 7, 8, 12, 14, 15}; +unsigned int local_irq = 1<<0 | 1<<1 | 1<<2 | 1<<7 | 1<<8 | 1<<12; static void ht_irqdispatch(void) { - unsigned int i, irq; + unsigned int i, irq, irq0, irq1; + static unsigned int dest_cpu = 0; irq = LOONGSON_HT1_INT_VECTOR(0); LOONGSON_HT1_INT_VECTOR(0) = irq; /* Acknowledge the IRQs */ + irq0 = irq & local_irq; /* handled by local core */ + irq1 = irq & ~local_irq; /* balanced by other cores */ + + if (dest_cpu == 0 || !cpu_online(dest_cpu)) + irq0 |= irq1; + else + loongson3_send_irq_by_ipi(dest_cpu, irq1); + + dest_cpu = dest_cpu + 1; + if (dest_cpu >= num_possible_cpus() || cpu_data[dest_cpu].package > 0) + dest_cpu = 0; + for (i = 0; i < ARRAY_SIZE(ht_irq); i++) { - if (irq & (0x1 << ht_irq[i])) + if (irq0 & (0x1 << ht_irq[i])) do_IRQ(ht_irq[i]); } } diff --git a/arch/mips/loongson64/loongson-3/smp.c b/arch/mips/loongson64/loongson-3/smp.c index 1629743ba96aa..b7a355c3c4081 100644 --- a/arch/mips/loongson64/loongson-3/smp.c +++ b/arch/mips/loongson64/loongson-3/smp.c @@ -254,13 +254,21 @@ loongson3_send_ipi_mask(const struct cpumask *mask, unsigned int action) loongson3_ipi_write32((u32)action, ipi_set0_regs[cpu_logical_map(i)]); } +#define IPI_IRQ_OFFSET 6 + +void loongson3_send_irq_by_ipi(int cpu, int irqs) +{ + loongson3_ipi_write32(irqs << IPI_IRQ_OFFSET, ipi_set0_regs[cpu_logical_map(cpu)]); +} + void loongson3_ipi_interrupt(struct pt_regs *regs) { int i, cpu = smp_processor_id(); - unsigned int action, c0count; + unsigned int action, c0count, irqs; /* Load the ipi register to figure out what we're supposed to do */ action = loongson3_ipi_read32(ipi_status0_regs[cpu_logical_map(cpu)]); + irqs = action >> IPI_IRQ_OFFSET; /* Clear the ipi register to clear the interrupt */ loongson3_ipi_write32((u32)action, ipi_clear0_regs[cpu_logical_map(cpu)]); @@ -282,6 +290,14 @@ void loongson3_ipi_interrupt(struct pt_regs *regs) core0_c0count[i] = c0count; __wbflush(); /* Let others see the result ASAP */ } + + if (irqs) { + int irq; + while ((irq = ffs(irqs))) { + do_IRQ(irq-1); + irqs &= ~(1<<(irq-1)); + } + } } #define MAX_LOOPS 800 -- 2.39.5