From f02cf4691e19ab61d4415b2fbfeb64aa8a93757e Mon Sep 17 00:00:00 2001 From: "Maciej W. Rozycki" Date: Fri, 3 Apr 2015 23:32:08 +0100 Subject: MIPS: DEC: Implement FPU interrupt counter Implement a cheap way to count FPU interrupts for R2k/R3k DECstation systems. Do this manually in handcoded assembly, rather than calling `kstat_incr_irq_this_cpu' that would require setting up a stack frame and a lot of redirection. This is not going to be a problem because the FPU interrupt is local to the CPU and also there is one CPU only anyway. So at bootstrap determine the address of the correct location within `struct irq_desc', and then only refer to it directly in the interrupt handler. Signed-off-by: Maciej W. Rozycki Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/9713/ Signed-off-by: Ralf Baechle --- arch/mips/dec/int-handler.S | 7 ++++++- arch/mips/dec/setup.c | 16 +++++++++++++--- 2 files changed, 19 insertions(+), 4 deletions(-) (limited to 'arch/mips/dec') diff --git a/arch/mips/dec/int-handler.S b/arch/mips/dec/int-handler.S index 41a2fa1fa12e..8c6f508e59de 100644 --- a/arch/mips/dec/int-handler.S +++ b/arch/mips/dec/int-handler.S @@ -267,8 +267,13 @@ handle_it: #ifdef CONFIG_32BIT fpu: + lw t0,fpu_kstat_irq + nop + lw t1,(t0) + nop + addu t1,1 j handle_fpe_int - nop + sw t1,(t0) #endif spurious: diff --git a/arch/mips/dec/setup.c b/arch/mips/dec/setup.c index 41bbffd9cc0e..b4f83dd22db6 100644 --- a/arch/mips/dec/setup.c +++ b/arch/mips/dec/setup.c @@ -12,13 +12,15 @@ #include #include #include +#include +#include #include #include +#include #include #include #include #include -#include #include #include @@ -98,6 +100,7 @@ int_ptr asic_mask_nr_tbl[DEC_MAX_ASIC_INTS][2] = { { { .i = ~0 }, { .p = asic_intr_unimplemented } }, }; int cpu_fpu_mask = DEC_CPU_IRQ_MASK(DEC_CPU_INR_FPU); +int *fpu_kstat_irq; static struct irqaction ioirq = { .handler = no_action, @@ -755,8 +758,15 @@ void __init arch_init_irq(void) dec_interrupt[DEC_IRQ_HALT] = -1; /* Register board interrupts: FPU and cascade. */ - if (dec_interrupt[DEC_IRQ_FPU] >= 0) - setup_irq(dec_interrupt[DEC_IRQ_FPU], &fpuirq); + if (dec_interrupt[DEC_IRQ_FPU] >= 0) { + struct irq_desc *desc_fpu; + int irq_fpu; + + irq_fpu = dec_interrupt[DEC_IRQ_FPU]; + setup_irq(irq_fpu, &fpuirq); + desc_fpu = irq_to_desc(irq_fpu); + fpu_kstat_irq = this_cpu_ptr(desc_fpu->kstat_irqs); + } if (dec_interrupt[DEC_IRQ_CASCADE] >= 0) setup_irq(dec_interrupt[DEC_IRQ_CASCADE], &ioirq); -- cgit v1.2.3