[PATCH V3 09/10] irqchip: Add Loongson Extended I/O interrupt controller support
From: Huacai Chen
Date: Wed Aug 25 2021 - 02:15:35 EST
We are preparing to add new Loongson (based on LoongArch, not MIPS)
support. This patch add Loongson Extended I/O CPU interrupt controller
support.
Signed-off-by: Huacai Chen <chenhuacai@xxxxxxxxxxx>
---
drivers/irqchip/Kconfig | 9 +
drivers/irqchip/Makefile | 1 +
drivers/irqchip/irq-loongson-eiointc.c | 326 +++++++++++++++++++++++++
include/linux/cpuhotplug.h | 1 +
4 files changed, 337 insertions(+)
create mode 100644 drivers/irqchip/irq-loongson-eiointc.c
diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index 443c3a7a0cc1..895b19fcea59 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -547,6 +547,15 @@ config LOONGSON_LIOINTC
help
Support for the Loongson Local I/O Interrupt Controller.
+config LOONGSON_EIOINTC
+ bool "Loongson Extend I/O Interrupt Controller"
+ depends on MACH_LOONGSON64
+ default MACH_LOONGSON64
+ select IRQ_DOMAIN_HIERARCHY
+ select GENERIC_IRQ_CHIP
+ help
+ Support for the Loongson3 Extend I/O Interrupt Vector Controller.
+
config LOONGSON_HTPIC
bool "Loongson3 HyperTransport PIC Controller"
depends on (MACH_LOONGSON64 && MIPS)
diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
index 4e34eebe180b..eb3fdc6fe808 100644
--- a/drivers/irqchip/Makefile
+++ b/drivers/irqchip/Makefile
@@ -107,6 +107,7 @@ obj-$(CONFIG_TI_SCI_INTA_IRQCHIP) += irq-ti-sci-inta.o
obj-$(CONFIG_TI_PRUSS_INTC) += irq-pruss-intc.o
obj-$(CONFIG_IRQ_LOONGARCH_CPU) += irq-loongarch-cpu.o
obj-$(CONFIG_LOONGSON_LIOINTC) += irq-loongson-liointc.o
+obj-$(CONFIG_LOONGSON_EIOINTC) += irq-loongson-eiointc.o
obj-$(CONFIG_LOONGSON_HTPIC) += irq-loongson-htpic.o
obj-$(CONFIG_LOONGSON_HTVEC) += irq-loongson-htvec.o
obj-$(CONFIG_LOONGSON_PCH_PIC) += irq-loongson-pch-pic.o
diff --git a/drivers/irqchip/irq-loongson-eiointc.c b/drivers/irqchip/irq-loongson-eiointc.c
new file mode 100644
index 000000000000..184e5f845400
--- /dev/null
+++ b/drivers/irqchip/irq-loongson-eiointc.c
@@ -0,0 +1,326 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Loongson Extend I/O Interrupt Controller support
+ *
+ * Copyright (C) 2020-2021 Loongson Technology Corporation Limited
+ */
+
+#define pr_fmt(fmt) "eiointc: " fmt
+
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/irqchip.h>
+#include <linux/irqdomain.h>
+#include <linux/irqchip/chained_irq.h>
+#include <linux/kernel.h>
+#include <linux/platform_device.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/of_platform.h>
+#include <linux/syscore_ops.h>
+
+#define EIOINTC_REG_NODEMAP 0x14a0
+#define EIOINTC_REG_IPMAP 0x14c0
+#define EIOINTC_REG_ENABLE 0x1600
+#define EIOINTC_REG_BOUNCE 0x1680
+#define EIOINTC_REG_ISR 0x1800
+#define EIOINTC_REG_ROUTE 0x1c00
+
+#define VEC_REG_COUNT 4
+#define VEC_COUNT_PER_REG 64
+#define VEC_COUNT (VEC_REG_COUNT * VEC_COUNT_PER_REG)
+#define VEC_REG_IDX(irq_id) ((irq_id) / VEC_COUNT_PER_REG)
+#define VEC_REG_BIT(irq_id) ((irq_id) % VEC_COUNT_PER_REG)
+
+struct eiointc_priv {
+ struct fwnode_handle *domain_handle;
+ struct irq_domain *eiointc_domain;
+ u32 eiointc_en[VEC_COUNT/32];
+};
+
+struct eiointc_priv *eiointc_priv;
+
+static void eiointc_set_irq_route(int pos, unsigned int cpu)
+{
+ int node, cpu_node, route_node;
+ unsigned char coremap[MAX_NUMNODES];
+ uint32_t pos_off, data, data_byte, data_mask;
+
+ pos_off = pos & ~3;
+ data_byte = pos & 3;
+ data_mask = ~BIT_MASK(data_byte) & 0xf;
+
+ memset(coremap, 0, sizeof(unsigned char) * MAX_NUMNODES);
+
+ /* Calculate node and coremap of target irq */
+ cpu_node = cpu_to_node(cpu);
+ coremap[cpu_node] |= (1 << (topology_core_id(cpu)));
+
+ for_each_online_node(node) {
+ data = 0ULL;
+
+ /* Node 0 is in charge of inter-node interrupt dispatch */
+ route_node = (node == 0) ? cpu_node : node;
+ data |= ((coremap[node] | (route_node << 4)) << (data_byte * 8));
+
+ csr_any_send(EIOINTC_REG_ROUTE + pos_off, data, data_mask, node);
+ }
+}
+
+static DEFINE_SPINLOCK(affinity_lock);
+
+static int eiointc_set_irq_affinity(struct irq_data *d, const struct cpumask *affinity,
+ bool force)
+{
+ unsigned int cpu;
+ unsigned long flags;
+ uint32_t vector, pos_off;
+
+ if (!IS_ENABLED(CONFIG_SMP))
+ return -EPERM;
+
+ spin_lock_irqsave(&affinity_lock, flags);
+
+ if (!cpumask_intersects(affinity, cpu_online_mask)) {
+ spin_unlock_irqrestore(&affinity_lock, flags);
+ return -EINVAL;
+ }
+ cpu = cpumask_first_and(affinity, cpu_online_mask);
+
+ /*
+ * Control interrupt enable or disalbe through cpu 0
+ * which is reponsible for dispatching interrupts.
+ */
+ vector = d->hwirq;
+ pos_off = vector >> 5;
+
+ csr_any_send(EIOINTC_REG_ENABLE + (pos_off << 2),
+ eiointc_priv->eiointc_en[pos_off] & (~((1 << (vector & 0x1F)))), 0x0, 0);
+
+ eiointc_set_irq_route(vector, cpu);
+ csr_any_send(EIOINTC_REG_ENABLE + (pos_off << 2),
+ eiointc_priv->eiointc_en[pos_off], 0x0, 0);
+ irq_data_update_effective_affinity(d, cpumask_of(cpu));
+
+ spin_unlock_irqrestore(&affinity_lock, flags);
+
+ return IRQ_SET_MASK_OK;
+}
+
+static int eiointc_router_init(unsigned int cpu)
+{
+ int i, bit;
+ uint32_t data;
+ uint32_t node = cpu_to_node(cpu);
+
+ if (cpu == cpumask_first(cpumask_of_node(node))) {
+ eiointc_enable();
+
+ for (i = 0; i < VEC_COUNT / 32; i++) {
+ data = (((1 << (i * 2 + 1)) << 16) | (1 << (i * 2)));
+ iocsr_writel(data, EIOINTC_REG_NODEMAP + i * 4);
+ }
+
+ for (i = 0; i < VEC_COUNT / 32 / 4; i++) {
+ data = 0x02020202; /* Route to IP3 */
+ iocsr_writel(data, EIOINTC_REG_IPMAP + i * 4);
+ }
+
+ for (i = 0; i < VEC_COUNT / 4; i++) {
+ /* Route to Node-0 Core-0 */
+ bit = BIT(cpu_logical_map(0));
+ data = bit | (bit << 8) | (bit << 16) | (bit << 24);
+ iocsr_writel(data, EIOINTC_REG_ROUTE + i * 4);
+ }
+
+ for (i = 0; i < VEC_COUNT / 32; i++) {
+ data = 0xffffffff;
+ iocsr_writel(data, EIOINTC_REG_ENABLE + i * 4);
+ iocsr_writel(data, EIOINTC_REG_BOUNCE + i * 4);
+ }
+ }
+
+ return 0;
+}
+
+static void eiointc_irq_dispatch(struct irq_desc *desc)
+{
+ int i;
+ u64 pending;
+ bool handled = false;
+ struct irq_chip *chip = irq_desc_get_chip(desc);
+ struct eiointc_priv *priv = irq_desc_get_handler_data(desc);
+
+ chained_irq_enter(chip, desc);
+
+ for (i = 0; i < VEC_REG_COUNT; i++) {
+ pending = iocsr_readq(EIOINTC_REG_ISR + (i << 3));
+ iocsr_writeq(pending, EIOINTC_REG_ISR + (i << 3));
+ while (pending) {
+ int bit = __ffs(pending);
+ int virq = irq_linear_revmap(priv->eiointc_domain, bit + VEC_COUNT_PER_REG * i);
+
+ generic_handle_irq(virq);
+ pending &= ~BIT(bit);
+ handled = true;
+ }
+ }
+
+ if (!handled)
+ spurious_interrupt();
+
+ chained_irq_exit(chip, desc);
+}
+
+static void eiointc_ack_irq(struct irq_data *d)
+{
+}
+
+static void eiointc_mask_irq(struct irq_data *d)
+{
+}
+
+static void eiointc_unmask_irq(struct irq_data *d)
+{
+}
+
+static struct irq_chip eiointc_irq_chip = {
+ .name = "EIOINTC",
+ .irq_ack = eiointc_ack_irq,
+ .irq_mask = eiointc_mask_irq,
+ .irq_unmask = eiointc_unmask_irq,
+ .irq_set_affinity = eiointc_set_irq_affinity,
+};
+
+static int eiointc_domain_alloc(struct irq_domain *domain, unsigned int virq,
+ unsigned int nr_irqs, void *arg)
+{
+ int ret;
+ unsigned int i, type;
+ unsigned long hwirq = 0;
+ struct eiointc *priv = domain->host_data;
+
+ ret = irq_domain_translate_onecell(domain, arg, &hwirq, &type);
+ if (ret)
+ return ret;
+
+ for (i = 0; i < nr_irqs; i++) {
+ irq_domain_set_info(domain, virq + i, hwirq + i, &eiointc_irq_chip,
+ priv, handle_edge_irq, NULL, NULL);
+ }
+
+ return 0;
+}
+
+static void eiointc_domain_free(struct irq_domain *domain, unsigned int virq,
+ unsigned int nr_irqs)
+{
+ int i;
+
+ for (i = 0; i < nr_irqs; i++) {
+ struct irq_data *d = irq_domain_get_irq_data(domain, virq + i);
+
+ irq_set_handler(virq + i, NULL);
+ irq_domain_reset_irq_data(d);
+ }
+}
+
+static const struct irq_domain_ops eiointc_domain_ops = {
+ .translate = irq_domain_translate_onecell,
+ .alloc = eiointc_domain_alloc,
+ .free = eiointc_domain_free,
+};
+
+static int eiointc_suspend(void)
+{
+ return 0;
+}
+
+static bool is_eiointc_irq(struct irq_data *irq_data)
+{
+ struct irq_domain *parent;
+
+ for (parent = irq_data->domain; parent; parent = parent->parent) {
+ if (parent == eiointc_priv->eiointc_domain)
+ return true;
+ }
+
+ return false;
+}
+
+static void eiointc_resume(void)
+{
+ int i;
+ struct irq_desc *desc;
+ struct irq_data *irq_data;
+
+ /* init irq en bitmap */
+ for (i = 0; i < VEC_COUNT / 32; i++)
+ eiointc_priv->eiointc_en[i] = 0xffffffff;
+
+ eiointc_router_init(0);
+
+ for (i = 0; i < NR_IRQS; i++) {
+ desc = irq_to_desc(i);
+ if (desc && desc->handle_irq && desc->handle_irq != handle_bad_irq) {
+ irq_data = &desc->irq_data;
+ if (!is_eiointc_irq(irq_data))
+ continue;
+
+ eiointc_set_irq_affinity(irq_data, irq_data->common->affinity, 0);
+ }
+ }
+}
+
+static struct syscore_ops eiointc_syscore_ops = {
+ .suspend = eiointc_suspend,
+ .resume = eiointc_resume,
+};
+
+struct fwnode_handle *eiointc_acpi_init(struct acpi_madt_eio_pic *acpi_eiointc)
+{
+ int i, parent_irq;
+ struct eiointc_priv *priv;
+
+ priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return NULL;
+
+ priv->domain_handle = irq_domain_alloc_fwnode((phys_addr_t *)acpi_eiointc);
+ if (!priv->domain_handle) {
+ pr_err("Unable to allocate domain handle\n");
+ goto out_free_priv;
+ }
+
+ /* Setup IRQ domain */
+ priv->eiointc_domain = irq_domain_create_linear(priv->domain_handle, VEC_COUNT,
+ &eiointc_domain_ops, priv);
+ if (!priv->eiointc_domain) {
+ pr_err("loongson-eiointc: cannot add IRQ domain\n");
+ goto out_free_priv;
+ }
+
+ /* init irq en bitmap */
+ for (i = 0; i < VEC_COUNT/32; i++)
+ priv->eiointc_en[i] = 0xffffffff;
+
+ eiointc_priv = priv;
+
+ eiointc_router_init(0);
+
+ parent_irq = LOONGSON_CPU_IRQ_BASE + acpi_eiointc->cascade;
+ irq_set_chained_handler_and_data(parent_irq, eiointc_irq_dispatch, priv);
+
+ register_syscore_ops(&eiointc_syscore_ops);
+ cpuhp_setup_state_nocalls(CPUHP_AP_IRQ_LOONGARCH_STARTING,
+ "irqchip/loongarch/intc:starting",
+ eiointc_router_init, NULL);
+
+ return eiointc_priv->domain_handle;
+
+out_free_priv:
+ priv->domain_handle = NULL;
+ kfree(priv);
+
+ return NULL;
+}
diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h
index f39b34b13871..34599ce0b18b 100644
--- a/include/linux/cpuhotplug.h
+++ b/include/linux/cpuhotplug.h
@@ -105,6 +105,7 @@ enum cpuhp_state {
CPUHP_AP_IRQ_BCM2836_STARTING,
CPUHP_AP_IRQ_MIPS_GIC_STARTING,
CPUHP_AP_IRQ_RISCV_STARTING,
+ CPUHP_AP_IRQ_LOONGARCH_STARTING,
CPUHP_AP_IRQ_SIFIVE_PLIC_STARTING,
CPUHP_AP_ARM_MVEBU_COHERENCY,
CPUHP_AP_MICROCODE_LOADER,
--
2.27.0