irqchip/qcom-pdc: Kill PDC_NO_PARENT_IRQ

PDC_NO_PARENT_IRQ is pretty pointless, as all it indicates is
that the PDC terminates the interrupt hierarchy. Which is
exactly the same as not having a mapping in the GIC space.
This is also bad practice to treat the absence of a hwirq
as a hwirq itself.

Just explicitly use the region mapping pointer, and drop
the definition.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Maulik Shah <quic_mkshah@quicinc.com>
Link: https://lore.kernel.org/r/20220224101226.88373-2-maz@kernel.org

diff --git a/drivers/irqchip/qcom-pdc.c b/drivers/irqchip/qcom-pdc.c
index 173e652..3b214c4 100644 (file)
--- a/drivers/irqchip/qcom-pdc.c
+++ b/drivers/irqchip/qcom-pdc.c
@@ -30,14 +30,14 @@
 #define IRQ_ENABLE_BANK                0x10
 #define IRQ_i_CFG              0x110
 
-#define PDC_NO_PARENT_IRQ      ~0UL
-
 struct pdc_pin_region {
        u32 pin_base;
        u32 parent_base;
        u32 cnt;
 };
 
+#define pin_to_hwirq(r, p)     ((r)->parent_base + (p) - (r)->pin_base)
+
 static DEFINE_RAW_SPINLOCK(pdc_lock);
 static void __iomem *pdc_base;
 static struct pdc_pin_region *pdc_region;
@@ -186,19 +186,17 @@ static struct irq_chip qcom_pdc_gic_chip = {
        .irq_set_affinity       = irq_chip_set_affinity_parent,
 };
 
-static irq_hw_number_t get_parent_hwirq(int pin)
+static struct pdc_pin_region *get_pin_region(int pin)
 {
        int i;
-       struct pdc_pin_region *region;
 
        for (i = 0; i < pdc_region_cnt; i++) {
-               region = &pdc_region[i];
-               if (pin >= region->pin_base &&
-                   pin < region->pin_base + region->cnt)
-                       return (region->parent_base + pin - region->pin_base);
+               if (pin >= pdc_region[i].pin_base &&
+                   pin < pdc_region[i].pin_base + pdc_region[i].cnt)
+                       return &pdc_region[i];
        }
 
-       return PDC_NO_PARENT_IRQ;
+       return NULL;
 }
 
 static int qcom_pdc_translate(struct irq_domain *d, struct irq_fwspec *fwspec,
@@ -221,7 +219,8 @@ static int qcom_pdc_alloc(struct irq_domain *domain, unsigned int virq,
 {
        struct irq_fwspec *fwspec = data;
        struct irq_fwspec parent_fwspec;
-       irq_hw_number_t hwirq, parent_hwirq;
+       struct pdc_pin_region *region;
+       irq_hw_number_t hwirq;
        unsigned int type;
        int ret;
 
@@ -234,8 +233,8 @@ static int qcom_pdc_alloc(struct irq_domain *domain, unsigned int virq,
        if (ret)
                return ret;
 
-       parent_hwirq = get_parent_hwirq(hwirq);
-       if (parent_hwirq == PDC_NO_PARENT_IRQ)
+       region = get_pin_region(hwirq);
+       if (!region)
                return irq_domain_disconnect_hierarchy(domain->parent, virq);
 
        if (type & IRQ_TYPE_EDGE_BOTH)
@@ -247,7 +246,7 @@ static int qcom_pdc_alloc(struct irq_domain *domain, unsigned int virq,
        parent_fwspec.fwnode      = domain->parent->fwnode;
        parent_fwspec.param_count = 3;
        parent_fwspec.param[0]    = 0;
-       parent_fwspec.param[1]    = parent_hwirq;
+       parent_fwspec.param[1]    = pin_to_hwirq(region, hwirq);
        parent_fwspec.param[2]    = type;
 
        return irq_domain_alloc_irqs_parent(domain, virq, nr_irqs,
@@ -265,7 +264,8 @@ static int qcom_pdc_gpio_alloc(struct irq_domain *domain, unsigned int virq,
 {
        struct irq_fwspec *fwspec = data;
        struct irq_fwspec parent_fwspec;
-       irq_hw_number_t hwirq, parent_hwirq;
+       struct pdc_pin_region *region;
+       irq_hw_number_t hwirq;
        unsigned int type;
        int ret;
 
@@ -281,8 +281,8 @@ static int qcom_pdc_gpio_alloc(struct irq_domain *domain, unsigned int virq,
        if (ret)
                return ret;
 
-       parent_hwirq = get_parent_hwirq(hwirq);
-       if (parent_hwirq == PDC_NO_PARENT_IRQ)
+       region = get_pin_region(hwirq);
+       if (!region)
                return irq_domain_disconnect_hierarchy(domain->parent, virq);
 
        if (type & IRQ_TYPE_EDGE_BOTH)
@@ -294,7 +294,7 @@ static int qcom_pdc_gpio_alloc(struct irq_domain *domain, unsigned int virq,
        parent_fwspec.fwnode      = domain->parent->fwnode;
        parent_fwspec.param_count = 3;
        parent_fwspec.param[0]    = 0;
-       parent_fwspec.param[1]    = parent_hwirq;
+       parent_fwspec.param[1]    = pin_to_hwirq(region, hwirq);
        parent_fwspec.param[2]    = type;
 
        return irq_domain_alloc_irqs_parent(domain, virq, nr_irqs,