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path: root/drivers/irqchip/qcom-pdc.c
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Diffstat (limited to 'drivers/irqchip/qcom-pdc.c')
-rw-r--r--drivers/irqchip/qcom-pdc.c311
1 files changed, 311 insertions, 0 deletions
diff --git a/drivers/irqchip/qcom-pdc.c b/drivers/irqchip/qcom-pdc.c
new file mode 100644
index 000000000000..b1b47a40a278
--- /dev/null
+++ b/drivers/irqchip/qcom-pdc.c
@@ -0,0 +1,311 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2017-2018, The Linux Foundation. All rights reserved.
+ */
+
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/irq.h>
+#include <linux/irqchip.h>
+#include <linux/irqdomain.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_device.h>
+#include <linux/spinlock.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+
+#define PDC_MAX_IRQS 126
+
+#define CLEAR_INTR(reg, intr) (reg & ~(1 << intr))
+#define ENABLE_INTR(reg, intr) (reg | (1 << intr))
+
+#define IRQ_ENABLE_BANK 0x10
+#define IRQ_i_CFG 0x110
+
+struct pdc_pin_region {
+ u32 pin_base;
+ u32 parent_base;
+ u32 cnt;
+};
+
+static DEFINE_RAW_SPINLOCK(pdc_lock);
+static void __iomem *pdc_base;
+static struct pdc_pin_region *pdc_region;
+static int pdc_region_cnt;
+
+static void pdc_reg_write(int reg, u32 i, u32 val)
+{
+ writel_relaxed(val, pdc_base + reg + i * sizeof(u32));
+}
+
+static u32 pdc_reg_read(int reg, u32 i)
+{
+ return readl_relaxed(pdc_base + reg + i * sizeof(u32));
+}
+
+static void pdc_enable_intr(struct irq_data *d, bool on)
+{
+ int pin_out = d->hwirq;
+ u32 index, mask;
+ u32 enable;
+
+ index = pin_out / 32;
+ mask = pin_out % 32;
+
+ raw_spin_lock(&pdc_lock);
+ enable = pdc_reg_read(IRQ_ENABLE_BANK, index);
+ enable = on ? ENABLE_INTR(enable, mask) : CLEAR_INTR(enable, mask);
+ pdc_reg_write(IRQ_ENABLE_BANK, index, enable);
+ raw_spin_unlock(&pdc_lock);
+}
+
+static void qcom_pdc_gic_mask(struct irq_data *d)
+{
+ pdc_enable_intr(d, false);
+ irq_chip_mask_parent(d);
+}
+
+static void qcom_pdc_gic_unmask(struct irq_data *d)
+{
+ pdc_enable_intr(d, true);
+ irq_chip_unmask_parent(d);
+}
+
+/*
+ * GIC does not handle falling edge or active low. To allow falling edge and
+ * active low interrupts to be handled at GIC, PDC has an inverter that inverts
+ * falling edge into a rising edge and active low into an active high.
+ * For the inverter to work, the polarity bit in the IRQ_CONFIG register has to
+ * set as per the table below.
+ * Level sensitive active low LOW
+ * Rising edge sensitive NOT USED
+ * Falling edge sensitive LOW
+ * Dual Edge sensitive NOT USED
+ * Level sensitive active High HIGH
+ * Falling Edge sensitive NOT USED
+ * Rising edge sensitive HIGH
+ * Dual Edge sensitive HIGH
+ */
+enum pdc_irq_config_bits {
+ PDC_LEVEL_LOW = 0b000,
+ PDC_EDGE_FALLING = 0b010,
+ PDC_LEVEL_HIGH = 0b100,
+ PDC_EDGE_RISING = 0b110,
+ PDC_EDGE_DUAL = 0b111,
+};
+
+/**
+ * qcom_pdc_gic_set_type: Configure PDC for the interrupt
+ *
+ * @d: the interrupt data
+ * @type: the interrupt type
+ *
+ * If @type is edge triggered, forward that as Rising edge as PDC
+ * takes care of converting falling edge to rising edge signal
+ * If @type is level, then forward that as level high as PDC
+ * takes care of converting falling edge to rising edge signal
+ */
+static int qcom_pdc_gic_set_type(struct irq_data *d, unsigned int type)
+{
+ int pin_out = d->hwirq;
+ enum pdc_irq_config_bits pdc_type;
+
+ switch (type) {
+ case IRQ_TYPE_EDGE_RISING:
+ pdc_type = PDC_EDGE_RISING;
+ break;
+ case IRQ_TYPE_EDGE_FALLING:
+ pdc_type = PDC_EDGE_FALLING;
+ type = IRQ_TYPE_EDGE_RISING;
+ break;
+ case IRQ_TYPE_EDGE_BOTH:
+ pdc_type = PDC_EDGE_DUAL;
+ break;
+ case IRQ_TYPE_LEVEL_HIGH:
+ pdc_type = PDC_LEVEL_HIGH;
+ break;
+ case IRQ_TYPE_LEVEL_LOW:
+ pdc_type = PDC_LEVEL_LOW;
+ type = IRQ_TYPE_LEVEL_HIGH;
+ break;
+ default:
+ WARN_ON(1);
+ return -EINVAL;
+ }
+
+ pdc_reg_write(IRQ_i_CFG, pin_out, pdc_type);
+
+ return irq_chip_set_type_parent(d, type);
+}
+
+static struct irq_chip qcom_pdc_gic_chip = {
+ .name = "PDC",
+ .irq_eoi = irq_chip_eoi_parent,
+ .irq_mask = qcom_pdc_gic_mask,
+ .irq_unmask = qcom_pdc_gic_unmask,
+ .irq_retrigger = irq_chip_retrigger_hierarchy,
+ .irq_set_type = qcom_pdc_gic_set_type,
+ .flags = IRQCHIP_MASK_ON_SUSPEND |
+ IRQCHIP_SET_TYPE_MASKED |
+ IRQCHIP_SKIP_SET_WAKE,
+ .irq_set_vcpu_affinity = irq_chip_set_vcpu_affinity_parent,
+ .irq_set_affinity = irq_chip_set_affinity_parent,
+};
+
+static irq_hw_number_t get_parent_hwirq(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);
+ }
+
+ WARN_ON(1);
+ return ~0UL;
+}
+
+static int qcom_pdc_translate(struct irq_domain *d, struct irq_fwspec *fwspec,
+ unsigned long *hwirq, unsigned int *type)
+{
+ if (is_of_node(fwspec->fwnode)) {
+ if (fwspec->param_count != 2)
+ return -EINVAL;
+
+ *hwirq = fwspec->param[0];
+ *type = fwspec->param[1] & IRQ_TYPE_SENSE_MASK;
+ return 0;
+ }
+
+ return -EINVAL;
+}
+
+static int qcom_pdc_alloc(struct irq_domain *domain, unsigned int virq,
+ unsigned int nr_irqs, void *data)
+{
+ struct irq_fwspec *fwspec = data;
+ struct irq_fwspec parent_fwspec;
+ irq_hw_number_t hwirq, parent_hwirq;
+ unsigned int type;
+ int ret;
+
+ ret = qcom_pdc_translate(domain, fwspec, &hwirq, &type);
+ if (ret)
+ return -EINVAL;
+
+ parent_hwirq = get_parent_hwirq(hwirq);
+ if (parent_hwirq == ~0UL)
+ return -EINVAL;
+
+ ret = irq_domain_set_hwirq_and_chip(domain, virq, hwirq,
+ &qcom_pdc_gic_chip, NULL);
+ if (ret)
+ return ret;
+
+ if (type & IRQ_TYPE_EDGE_BOTH)
+ type = IRQ_TYPE_EDGE_RISING;
+
+ if (type & IRQ_TYPE_LEVEL_MASK)
+ type = IRQ_TYPE_LEVEL_HIGH;
+
+ 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[2] = type;
+
+ return irq_domain_alloc_irqs_parent(domain, virq, nr_irqs,
+ &parent_fwspec);
+}
+
+static const struct irq_domain_ops qcom_pdc_ops = {
+ .translate = qcom_pdc_translate,
+ .alloc = qcom_pdc_alloc,
+ .free = irq_domain_free_irqs_common,
+};
+
+static int pdc_setup_pin_mapping(struct device_node *np)
+{
+ int ret, n;
+
+ n = of_property_count_elems_of_size(np, "qcom,pdc-ranges", sizeof(u32));
+ if (n <= 0 || n % 3)
+ return -EINVAL;
+
+ pdc_region_cnt = n / 3;
+ pdc_region = kcalloc(pdc_region_cnt, sizeof(*pdc_region), GFP_KERNEL);
+ if (!pdc_region) {
+ pdc_region_cnt = 0;
+ return -ENOMEM;
+ }
+
+ for (n = 0; n < pdc_region_cnt; n++) {
+ ret = of_property_read_u32_index(np, "qcom,pdc-ranges",
+ n * 3 + 0,
+ &pdc_region[n].pin_base);
+ if (ret)
+ return ret;
+ ret = of_property_read_u32_index(np, "qcom,pdc-ranges",
+ n * 3 + 1,
+ &pdc_region[n].parent_base);
+ if (ret)
+ return ret;
+ ret = of_property_read_u32_index(np, "qcom,pdc-ranges",
+ n * 3 + 2,
+ &pdc_region[n].cnt);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+
+static int qcom_pdc_init(struct device_node *node, struct device_node *parent)
+{
+ struct irq_domain *parent_domain, *pdc_domain;
+ int ret;
+
+ pdc_base = of_iomap(node, 0);
+ if (!pdc_base) {
+ pr_err("%pOF: unable to map PDC registers\n", node);
+ return -ENXIO;
+ }
+
+ parent_domain = irq_find_host(parent);
+ if (!parent_domain) {
+ pr_err("%pOF: unable to find PDC's parent domain\n", node);
+ ret = -ENXIO;
+ goto fail;
+ }
+
+ ret = pdc_setup_pin_mapping(node);
+ if (ret) {
+ pr_err("%pOF: failed to init PDC pin-hwirq mapping\n", node);
+ goto fail;
+ }
+
+ pdc_domain = irq_domain_create_hierarchy(parent_domain, 0, PDC_MAX_IRQS,
+ of_fwnode_handle(node),
+ &qcom_pdc_ops, NULL);
+ if (!pdc_domain) {
+ pr_err("%pOF: GIC domain add failed\n", node);
+ ret = -ENOMEM;
+ goto fail;
+ }
+
+ return 0;
+
+fail:
+ kfree(pdc_region);
+ iounmap(pdc_base);
+ return ret;
+}
+
+IRQCHIP_DECLARE(pdc_sdm845, "qcom,sdm845-pdc", qcom_pdc_init);