Commit e1b88ca8 authored by Huacai Chen's avatar Huacai Chen Committed by Ralf Baechle

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: default avatarHuacai Chen <chenhc@lemote.com>
Cc: John Crispin <john@phrozen.org>
Cc: Steven J . Hill <Steven.Hill@cavium.com>
Cc: Fuxin Zhang <zhangfx@lemote.com>
Cc: Zhangjin Wu <wuzhangjin@gmail.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16589/Signed-off-by: default avatarRalf Baechle <ralf@linux-mips.org>
parent 99b0b5a3
...@@ -9,17 +9,32 @@ ...@@ -9,17 +9,32 @@
#include "smp.h" #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 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) 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); irq = LOONGSON_HT1_INT_VECTOR(0);
LOONGSON_HT1_INT_VECTOR(0) = irq; /* Acknowledge the IRQs */ 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++) { 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]); do_IRQ(ht_irq[i]);
} }
} }
......
...@@ -254,13 +254,21 @@ loongson3_send_ipi_mask(const struct cpumask *mask, unsigned int action) ...@@ -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)]); 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) void loongson3_ipi_interrupt(struct pt_regs *regs)
{ {
int i, cpu = smp_processor_id(); 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 */ /* Load the ipi register to figure out what we're supposed to do */
action = loongson3_ipi_read32(ipi_status0_regs[cpu_logical_map(cpu)]); action = loongson3_ipi_read32(ipi_status0_regs[cpu_logical_map(cpu)]);
irqs = action >> IPI_IRQ_OFFSET;
/* Clear the ipi register to clear the interrupt */ /* Clear the ipi register to clear the interrupt */
loongson3_ipi_write32((u32)action, ipi_clear0_regs[cpu_logical_map(cpu)]); loongson3_ipi_write32((u32)action, ipi_clear0_regs[cpu_logical_map(cpu)]);
...@@ -282,6 +290,14 @@ void loongson3_ipi_interrupt(struct pt_regs *regs) ...@@ -282,6 +290,14 @@ void loongson3_ipi_interrupt(struct pt_regs *regs)
core0_c0count[i] = c0count; core0_c0count[i] = c0count;
__wbflush(); /* Let others see the result ASAP */ __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 #define MAX_LOOPS 800
......
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