From c7cad38d37486668a448215fc92bace9c8cf747a Mon Sep 17 00:00:00 2001 From: Florian Fainelli Date: Wed, 24 Apr 2024 10:57:32 -0700 Subject: [PATCH] irqchip/irq-brcmstb-l2: Avoid saving mask on shutdown The interrupt controller shutdown path does not need to save the mask of enabled interrupts because the next state the system is going to be in is akin to a cold boot, or a kexec'd kernel. Saving the mask only makes sense if the software state needs to preserve the hardware state across a system suspend/resume cycle. As an optimization, and given that there are systems with dozens of such interrupt controller, save a "slow" memory mapped I/O read in the shutdown path where no saving/restoring is required. Reported-by: Tim Ross Signed-off-by: Florian Fainelli Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/r/20240424175732.1526531-1-florian.fainelli@broadcom.com --- drivers/irqchip/irq-brcmstb-l2.c | 17 ++++++++++++++--- 1 file changed, 14 insertions(+), 3 deletions(-) diff --git a/drivers/irqchip/irq-brcmstb-l2.c b/drivers/irqchip/irq-brcmstb-l2.c index 2b0b3175cea0..c988886917f7 100644 --- a/drivers/irqchip/irq-brcmstb-l2.c +++ b/drivers/irqchip/irq-brcmstb-l2.c @@ -118,7 +118,7 @@ static void brcmstb_l2_intc_irq_handle(struct irq_desc *desc) chained_irq_exit(chip, desc); } -static void brcmstb_l2_intc_suspend(struct irq_data *d) +static void __brcmstb_l2_intc_suspend(struct irq_data *d, bool save) { struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); struct irq_chip_type *ct = irq_data_get_chip_type(d); @@ -127,7 +127,8 @@ static void brcmstb_l2_intc_suspend(struct irq_data *d) irq_gc_lock_irqsave(gc, flags); /* Save the current mask */ - b->saved_mask = irq_reg_readl(gc, ct->regs.mask); + if (save) + b->saved_mask = irq_reg_readl(gc, ct->regs.mask); if (b->can_wake) { /* Program the wakeup mask */ @@ -137,6 +138,16 @@ static void brcmstb_l2_intc_suspend(struct irq_data *d) irq_gc_unlock_irqrestore(gc, flags); } +static void brcmstb_l2_intc_shutdown(struct irq_data *d) +{ + __brcmstb_l2_intc_suspend(d, false); +} + +static void brcmstb_l2_intc_suspend(struct irq_data *d) +{ + __brcmstb_l2_intc_suspend(d, true); +} + static void brcmstb_l2_intc_resume(struct irq_data *d) { struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); @@ -252,7 +263,7 @@ static int __init brcmstb_l2_intc_of_init(struct device_node *np, ct->chip.irq_suspend = brcmstb_l2_intc_suspend; ct->chip.irq_resume = brcmstb_l2_intc_resume; - ct->chip.irq_pm_shutdown = brcmstb_l2_intc_suspend; + ct->chip.irq_pm_shutdown = brcmstb_l2_intc_shutdown; if (data->can_wake) { /* This IRQ chip can wake the system, set all child interrupts