Re: [PATCH V14 12/15] irqchip: Add Loongson Extended I/O interrupt controller support

Jianmin Lv
2022-07-08T11:31:28Z

Hi, bibo

Thanks for your suggestion. Yes, the logic is more complex on multiple
node, but I think we should support both single and multiple nodes at
same time as the driver supported both from beginng and has been
verified on them. Of cause, I'm very happy to discuss issues about the
driver.:)

On 2022/7/7 下午9:22, maobibo wrote:
> Jianmin,
>
> Since eiointc driver for loongarch comes from scratch,
> can we add only single node support for eiointc at beginning?
> And then add multiple-node support after the first version merged.
>
> To be frankly, it is actually hard to understand logic of eiointc
> for multiple-node support. However it is just my suggestion from my point
> and the final code and decision comes from your self.
>
> regards
> bibo,mao
>
> 在 2022/7/3 16:45, Jianmin Lv 写道:
>> From: Huacai Chen <chenhuacai@loongson.cn>
>>
>> EIOINTC stands for "Extended I/O Interrupts" that described in Section
>> 11.2 of "Loongson 3A5000 Processor Reference Manual". For more
>> information please refer Documentation/loongarch/irq-chip-model.rst.
>>
>> Loongson-3A5000 has 4 cores per NUMA node, and each NUMA node has an
>> EIOINTC; while Loongson-3C5000 has 16 cores per NUMA node, and each NUMA
>> node has 4 EIOINTCs. In other words, 16 cores of one NUMA node in
>> Loongson-3C5000 are organized in 4 groups, each group connects to an
>> EIOINTC. We call the "group" here as an EIOINTC node, so each EIOINTC
>> node always includes 4 cores (both in Loongson-3A5000 and Loongson-
>> 3C5000).
>>
>> Co-developed-by: Jianmin Lv <lvjianmin@loongson.cn>
>> Signed-off-by: Jianmin Lv <lvjianmin@loongson.cn>
>> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
>> ---
>> arch/loongarch/include/asm/irq.h | 11 +-
>> drivers/irqchip/Kconfig | 10 +
>> drivers/irqchip/Makefile | 1 +
>> drivers/irqchip/irq-loongson-eiointc.c | 413 +++++++++++++++++++++++++++++++++
>> include/linux/cpuhotplug.h | 1 +
>> 5 files changed, 426 insertions(+), 10 deletions(-)
>> create mode 100644 drivers/irqchip/irq-loongson-eiointc.c
>>
>> diff --git a/arch/loongarch/include/asm/irq.h b/arch/loongarch/include/asm/irq.h
>> index a07315a..a826ac4 100644
>> --- a/arch/loongarch/include/asm/irq.h
>> +++ b/arch/loongarch/include/asm/irq.h
>> @@ -87,15 +87,6 @@ struct acpi_vector_group {
>> extern int find_pch_pic(u32 gsi);
>> extern int eiointc_get_node(int id);
>>
>> -static inline void eiointc_enable(void)
>> -{
>> - uint64_t misc;
>> -
>> - misc = iocsr_read64(LOONGARCH_IOCSR_MISC_FUNC);
>> - misc |= IOCSR_MISC_FUNC_EXT_IOI_EN;
>> - iocsr_write64(misc, LOONGARCH_IOCSR_MISC_FUNC);
>> -}
>> -
>> struct acpi_madt_lio_pic;
>> struct acpi_madt_eio_pic;
>> struct acpi_madt_ht_pic;
>> @@ -107,7 +98,7 @@ static inline void eiointc_enable(void)
>>
>> int liointc_acpi_init(struct irq_domain *parent,
>> struct acpi_madt_lio_pic *acpi_liointc);
>> -struct irq_domain *eiointc_acpi_init(struct irq_domain *parent,
>> +int eiointc_acpi_init(struct irq_domain *parent,
>> struct acpi_madt_eio_pic *acpi_eiointc);
>>
>> int htvec_acpi_init(struct irq_domain *parent,
>> diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
>> index c1d527f..e918579 100644
>> --- a/drivers/irqchip/Kconfig
>> +++ b/drivers/irqchip/Kconfig
>> @@ -555,6 +555,16 @@ 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 LOONGARCH
>> + 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 242b8b3..0cfd4f0 100644
>> --- a/drivers/irqchip/Makefile
>> +++ b/drivers/irqchip/Makefile
>> @@ -104,6 +104,7 @@ obj-$(CONFIG_TI_SCI_INTR_IRQCHIP) += irq-ti-sci-intr.o
>> obj-$(CONFIG_TI_SCI_INTA_IRQCHIP) += irq-ti-sci-inta.o
>> obj-$(CONFIG_TI_PRUSS_INTC) += irq-pruss-intc.o
>> obj-$(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 0000000..9ddb9ac
>> --- /dev/null
>> +++ b/drivers/irqchip/irq-loongson-eiointc.c
>> @@ -0,0 +1,413 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/*
>> + * Loongson Extend I/O Interrupt Controller support
>> + *
>> + * Copyright (C) 2020-2022 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>
>> +
>> +#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)
>> +#define EIOINTC_ALL_ENABLE 0xffffffff
>> +
>> +#define MAX_EIO_NODES (NR_CPUS / CORES_PER_EIO_NODE)
>> +
>> +static int nr_pics;
>> +
>> +struct eiointc_priv {
>> + u32 node;
>> + nodemask_t node_map;
>> + cpumask_t cpuspan_map;
>> + struct fwnode_handle *domain_handle;
>> + struct irq_domain *eiointc_domain;
>> +};
>> +
>> +static struct eiointc_priv *eiointc_priv[MAX_IO_PICS];
>> +
>> +static void eiointc_enable(void)
>> +{
>> + uint64_t misc;
>> +
>> + misc = iocsr_read64(LOONGARCH_IOCSR_MISC_FUNC);
>> + misc |= IOCSR_MISC_FUNC_EXT_IOI_EN;
>> + iocsr_write64(misc, LOONGARCH_IOCSR_MISC_FUNC);
>> +}
>> +
>> +static int cpu_to_eio_node(int cpu)
>> +{
>> + return cpu_logical_map(cpu) / CORES_PER_EIO_NODE;
>> +}
>> +
>> +static void eiointc_set_irq_route(int pos, unsigned int cpu, unsigned int mnode, nodemask_t *node_map)
>> +{
>> + int i, node, cpu_node, route_node;
>> + unsigned char coremap[MAX_EIO_NODES];
>> + 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_EIO_NODES);
>> +
>> + /* Calculate node and coremap of target irq */
>> + cpu_node = cpu_logical_map(cpu) / CORES_PER_EIO_NODE;
>> + coremap[cpu_node] |= BIT(cpu_logical_map(cpu) % CORES_PER_EIO_NODE);
>> +
>> + for_each_online_cpu(i) {
>> + node = cpu_to_eio_node(i);
>> + if (!node_isset(node, *node_map))
>> + continue;
>> +
>> + /* EIO node 0 is in charge of inter-node interrupt dispatch */
>> + route_node = (node == mnode) ? cpu_node : node;
>> + data = ((coremap[node] | (route_node << 4)) << (data_byte * 8));
>> + csr_any_send(EIOINTC_REG_ROUTE + pos_off, data, data_mask, node * CORES_PER_EIO_NODE);
>> + }
>> +}
>> +
>> +static DEFINE_RAW_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, regaddr;
>> + struct cpumask intersect_affinity;
>> + struct eiointc_priv *priv = d->domain->host_data;
>> +
>> + if (!IS_ENABLED(CONFIG_SMP))
>> + return -EPERM;
>> +
>> + raw_spin_lock_irqsave(&affinity_lock, flags);
>> +
>> + cpumask_and(&intersect_affinity, affinity, cpu_online_mask);
>> + cpumask_and(&intersect_affinity, &intersect_affinity, &priv->cpuspan_map);
>> +
>> + if (cpumask_empty(&intersect_affinity)) {
>> + raw_spin_unlock_irqrestore(&affinity_lock, flags);
>> + return -EINVAL;
>> + }
>> + cpu = cpumask_first(&intersect_affinity);
>> +
>> + if (!d->parent_data)
>> + vector = d->hwirq;
>> + else
>> + vector = d->parent_data->hwirq;
>> +
>> + regaddr = EIOINTC_REG_ENABLE + ((vector >> 5) << 2);
>> +
>> + /* Mask target vector */
>> + csr_any_send(regaddr, EIOINTC_ALL_ENABLE & (~BIT(vector & 0x1F)), 0x0, 0);
>> + /* Set route for target vector */
>> + eiointc_set_irq_route(vector, cpu, priv->node, &priv->node_map);
>> + /* Unmask target vector */
>> + csr_any_send(regaddr, EIOINTC_ALL_ENABLE, 0x0, 0);
>> +
>> + irq_data_update_effective_affinity(d, cpumask_of(cpu));
>> +
>> + raw_spin_unlock_irqrestore(&affinity_lock, flags);
>> +
>> + return IRQ_SET_MASK_OK;
>> +}
>> +
>> +static int eiointc_index(int node)
>> +{
>> + int i;
>> +
>> + for (i = 0; i < nr_pics; i++) {
>> + if (node_isset(node, eiointc_priv[i]->node_map))
>> + return i;
>> + }
>> +
>> + return -1;
>> +}
>> +
>> +static int eiointc_router_init(unsigned int cpu)
>> +{
>> + int i, bit;
>> + uint32_t data;
>> + uint32_t node = cpu_to_eio_node(cpu);
>> + uint32_t index = eiointc_index(node);
>> +
>> + if (index < 0) {
>> + pr_err("Error: invalid nodemap!\n");
>> + return -1;
>> + }
>> +
>> + if ((cpu_logical_map(cpu) % CORES_PER_EIO_NODE) == 0) {
>> + eiointc_enable();
>> +
>> + for (i = 0; i < VEC_COUNT / 32; i++) {
>> + data = (((1 << (i * 2 + 1)) << 16) | (1 << (i * 2)));
>> + iocsr_write32(data, EIOINTC_REG_NODEMAP + i * 4);
>> + }
>> +
>> + for (i = 0; i < VEC_COUNT / 32 / 4; i++) {
>> + bit = BIT(1 + index); /* Route to IP[1 + index] */
>> + data = bit | (bit << 8) | (bit << 16) | (bit << 24);
>> + iocsr_write32(data, EIOINTC_REG_IPMAP + i * 4);
>> + }
>> +
>> + for (i = 0; i < VEC_COUNT / 4; i++) {
>> + /* Route to Node-0 Core-0 */
>> + if (index == 0)
>> + bit = BIT(cpu_logical_map(0));
>> + else
>> + bit = (eiointc_priv[index]->node << 4) | 1;
>> +
>> + data = bit | (bit << 8) | (bit << 16) | (bit << 24);
>> + iocsr_write32(data, EIOINTC_REG_ROUTE + i * 4);
>> + }
>> +
>> + for (i = 0; i < VEC_COUNT / 32; i++) {
>> + data = 0xffffffff;
>> + iocsr_write32(data, EIOINTC_REG_ENABLE + i * 4);
>> + iocsr_write32(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_read64(EIOINTC_REG_ISR + (i << 3));
>> + iocsr_write64(pending, EIOINTC_REG_ISR + (i << 3));
>> + while (pending) {
>> + int bit = __ffs(pending);
>> + int irq = bit + VEC_COUNT_PER_REG * i;
>> +
>> + generic_handle_domain_irq(priv->eiointc_domain, irq);
>> + pending &= ~BIT(bit);
>> + handled = true;
>> + }
>> + }
>> +
>> + if (!handled)
>> + spurious_interrupt();
>> +
>> + chained_irq_exit(chip, desc);
>> +}
>> +
>> +static void eiointc_ack_irq(struct irq_data *d)
>> +{
>> + if (d->parent_data)
>> + irq_chip_ack_parent(d);
>> +}
>> +
>> +static void eiointc_mask_irq(struct irq_data *d)
>> +{
>> + if (d->parent_data)
>> + irq_chip_mask_parent(d);
>> +}
>> +
>> +static void eiointc_unmask_irq(struct irq_data *d)
>> +{
>> + if (d->parent_data)
>> + irq_chip_unmask_parent(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 void acpi_set_vec_parent(int node, struct irq_domain *parent, struct acpi_vector_group *vec_group)
>> +{
>> + int i;
>> +
>> + if (cpu_has_flatmode)
>> + node = cpu_to_node(node * CORES_PER_EIO_NODE);
>> +
>> + for (i = 0; i < MAX_IO_PICS; i++) {
>> + if (node == vec_group[i].node) {
>> + vec_group[i].parent = parent;
>> + return;
>> + }
>> + }
>> +}
>> +
>> +struct irq_domain *acpi_get_vec_parent(int node, struct acpi_vector_group *vec_group)
>> +{
>> + int i;
>> +
>> + for (i = 0; i < MAX_IO_PICS; i++) {
>> + if (node == vec_group[i].node)
>> + return vec_group[i].parent;
>> + }
>> + return NULL;
>> +}
>> +
>> +static int __init
>> +pch_pic_parse_madt(union acpi_subtable_headers *header,
>> + const unsigned long end)
>> +{
>> + struct acpi_madt_bio_pic *pchpic_entry = (struct acpi_madt_bio_pic *)header;
>> + unsigned int node = (pchpic_entry->address >> 44) & 0xf;
>> + struct irq_domain *parent = acpi_get_vec_parent(node, pch_group);
>> +
>> + if (parent)
>> + return pch_pic_acpi_init(parent, pchpic_entry);
>> +
>> + return -EINVAL;
>> +}
>> +
>> +static int __init
>> +pch_msi_parse_madt(union acpi_subtable_headers *header,
>> + const unsigned long end)
>> +{
>> + struct acpi_madt_msi_pic *pchmsi_entry = (struct acpi_madt_msi_pic *)header;
>> + struct irq_domain *parent = acpi_get_vec_parent(eiointc_priv[nr_pics - 1]->node, msi_group);
>> +
>> + if (parent)
>> + return pch_msi_acpi_init(parent, pchmsi_entry);
>> +
>> + return -EINVAL;
>> +}
>> +
>> +static int __init acpi_cascade_irqdomain_init(void)
>> +{
>> + acpi_table_parse_madt(ACPI_MADT_TYPE_BIO_PIC,
>> + pch_pic_parse_madt, 0);
>> + acpi_table_parse_madt(ACPI_MADT_TYPE_MSI_PIC,
>> + pch_msi_parse_madt, 1);
>> + return 0;
>> +}
>> +
>> +int __init eiointc_acpi_init(struct irq_domain *parent,
>> + struct acpi_madt_eio_pic *acpi_eiointc)
>> +{
>> + int i, parent_irq;
>> + unsigned long node_map;
>> + struct eiointc_priv *priv;
>> +
>> + if (!acpi_eiointc)
>> + return -EINVAL;
>> +
>> + priv = kzalloc(sizeof(*priv), GFP_KERNEL);
>> + if (!priv)
>> + return -ENOMEM;
>> +
>> + 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;
>> + }
>> +
>> + priv->node = acpi_eiointc->node;
>> + node_map = acpi_eiointc->node_map ? : -1ULL;
>> +
>> + for_each_possible_cpu(i) {
>> + if (node_map & (1ULL << cpu_to_eio_node(i))) {
>> + node_set(cpu_to_eio_node(i), priv->node_map);
>> + cpumask_or(&priv->cpuspan_map, &priv->cpuspan_map, cpumask_of(i));
>> + }
>> + }
>> +
>> + /* 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_handle;
>> + }
>> +
>> + eiointc_priv[nr_pics++] = priv;
>> +
>> + eiointc_router_init(0);
>> +
>> + parent_irq = irq_create_mapping(parent, acpi_eiointc->cascade);
>> + irq_set_chained_handler_and_data(parent_irq, eiointc_irq_dispatch, priv);
>> +
>> + cpuhp_setup_state_nocalls(CPUHP_AP_IRQ_LOONGARCH_STARTING,
>> + "irqchip/loongarch/intc:starting",
>> + eiointc_router_init, NULL);
>> +
>> + acpi_set_vec_parent(acpi_eiointc->node, priv->eiointc_domain, pch_group);
>> + acpi_set_vec_parent(acpi_eiointc->node, priv->eiointc_domain, msi_group);
>> + acpi_cascade_irqdomain_init();
>> +
>> + return 0;
>> +
>> +out_free_handle:
>> + irq_domain_free_fwnode(priv->domain_handle);
>> + priv->domain_handle = NULL;
>> +out_free_priv:
>> + kfree(priv);
>> +
>> + return -ENOMEM;
>> +}
>> diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h
>> index 19f0dbf..de662f3 100644
>> --- a/include/linux/cpuhotplug.h
>> +++ b/include/linux/cpuhotplug.h
>> @@ -151,6 +151,7 @@ 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,