[PATCH RFC V3 05/11] irqchip: create library file for LoongArch irqchip driver

From: Jianmin Lv
Date: Sat Jun 11 2022 - 07:04:16 EST


The library file contains following content:
- Implement acpi_get_gsi_domain_id callback.
- Implement initialization of vector group entries and APIs
for building hierachy irqdomains.

Signed-off-by: Jianmin Lv <lvjianmin@xxxxxxxxxxx>
---
drivers/irqchip/Makefile | 2 +-
drivers/irqchip/irq-loongarch-pic-common.c | 122 +++++++++++++++++++++++++++++
drivers/irqchip/irq-loongarch-pic-common.h | 39 +++++++++
3 files changed, 162 insertions(+), 1 deletion(-)
create mode 100644 drivers/irqchip/irq-loongarch-pic-common.c
create mode 100644 drivers/irqchip/irq-loongarch-pic-common.h

diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
index 42724fc..433e91d 100644
--- a/drivers/irqchip/Makefile
+++ b/drivers/irqchip/Makefile
@@ -105,7 +105,7 @@ obj-$(CONFIG_LS1X_IRQ) += irq-ls1x.o
obj-$(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-$(CONFIG_IRQ_LOONGARCH_CPU) += irq-loongarch-cpu.o
+obj-$(CONFIG_IRQ_LOONGARCH_CPU) += irq-loongarch-cpu.o irq-loongarch-pic-common.o
obj-$(CONFIG_LOONGSON_LIOINTC) += irq-loongson-liointc.o
obj-$(CONFIG_LOONGSON_HTPIC) += irq-loongson-htpic.o
obj-$(CONFIG_LOONGSON_HTVEC) += irq-loongson-htvec.o
diff --git a/drivers/irqchip/irq-loongarch-pic-common.c b/drivers/irqchip/irq-loongarch-pic-common.c
new file mode 100644
index 0000000..2f75362
--- /dev/null
+++ b/drivers/irqchip/irq-loongarch-pic-common.c
@@ -0,0 +1,122 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2022 Loongson Limited, All Rights Reserved.
+ */
+
+#include <linux/irq.h>
+#include <linux/pci.h>
+#include <linux/acpi.h>
+#include "irq-loongarch-pic-common.h"
+
+static struct acpi_vector_group vector_group[MAX_IO_PICS];
+
+struct acpi_madt_bio_pic *acpi_pchpic[MAX_IO_PICS];
+
+struct fwnode_handle *liointc_handle;
+struct fwnode_handle *pch_lpc_handle;
+struct fwnode_handle *pch_msi_handle[MAX_IO_PICS];
+struct fwnode_handle *pch_pic_handle[MAX_IO_PICS];
+
+static int find_pch_pic(u32 gsi)
+{
+ int i, start, end;
+
+ /* Find the PCH_PIC that manages this GSI. */
+ for (i = 0; i < MAX_IO_PICS; i++) {
+ struct acpi_madt_bio_pic *irq_cfg = acpi_pchpic[i];
+
+ if (!irq_cfg)
+ return -1;
+
+ start = irq_cfg->gsi_base;
+ end = irq_cfg->gsi_base + irq_cfg->size;
+ if (gsi >= start && gsi < end)
+ return i;
+ }
+
+ pr_err("ERROR: Unable to locate PCH_PIC for GSI %d\n", gsi);
+ return -1;
+}
+
+struct fwnode_handle *lpic_get_gsi_domain_id(u32 gsi)
+{
+ int id;
+ struct fwnode_handle *domain_handle = NULL;
+
+ switch (gsi) {
+ case GSI_MIN_CPU_IRQ ... GSI_MAX_CPU_IRQ:
+ if (liointc_handle)
+ domain_handle = liointc_handle;
+ break;
+
+ case GSI_MIN_LPC_IRQ ... GSI_MAX_LPC_IRQ:
+ if (pch_lpc_handle)
+ domain_handle = pch_lpc_handle;
+ break;
+
+ case GSI_MIN_PCH_IRQ ... GSI_MAX_PCH_IRQ:
+ id = find_pch_pic(gsi);
+ if (id >= 0 && pch_pic_handle[id])
+ domain_handle = pch_pic_handle[id];
+
+ break;
+ }
+
+ return domain_handle;
+}
+
+static int pci_mcfg_parse(struct acpi_table_header *header)
+{
+ struct acpi_table_mcfg *mcfg;
+ struct acpi_mcfg_allocation *mptr;
+ int i, n;
+
+ if (header->length < sizeof(struct acpi_table_mcfg))
+ return -EINVAL;
+
+ n = (header->length - sizeof(struct acpi_table_mcfg)) /
+ sizeof(struct acpi_mcfg_allocation);
+ mcfg = (struct acpi_table_mcfg *)header;
+ mptr = (struct acpi_mcfg_allocation *) &mcfg[1];
+
+ for (i = 0; i < n; i++, mptr++)
+ vector_group[mptr->pci_segment].node = (mptr->address >> 44) & 0xf;
+
+ return 0;
+}
+
+void __init init_vector_parent_group(void)
+{
+ acpi_table_parse(ACPI_SIG_MCFG, pci_mcfg_parse);
+}
+
+void acpi_set_vector_parent(int node, struct irq_domain *parent)
+{
+ 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 == vector_group[i].node) {
+ vector_group[i].parent = parent;
+ return;
+ }
+ }
+}
+
+struct irq_domain *acpi_get_msi_parent(int index)
+{
+ return vector_group[index].parent;
+}
+
+struct irq_domain *acpi_get_pch_parent(int node)
+{
+ int i;
+
+ for (i = 0; i < MAX_IO_PICS; i++) {
+ if (node == vector_group[i].node)
+ return vector_group[i].parent;
+ }
+ return NULL;
+}
diff --git a/drivers/irqchip/irq-loongarch-pic-common.h b/drivers/irqchip/irq-loongarch-pic-common.h
new file mode 100644
index 0000000..3e068c3
--- /dev/null
+++ b/drivers/irqchip/irq-loongarch-pic-common.h
@@ -0,0 +1,39 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2022 Loongson Limited, All Rights Reserved.
+ */
+
+#ifndef _IRQ_LOONGARCH_PIC_COMMON_H
+#define _IRQ_LOONGARCH_PIC_COMMON_H
+
+#include <linux/of.h>
+#include <linux/irqdomain.h>
+
+struct acpi_vector_group {
+ int node;
+ struct irq_domain *parent;
+};
+
+/* IRQ number definitions */
+#define LOONGSON_LPC_IRQ_BASE 0
+#define LOONGSON_CPU_IRQ_BASE 16
+#define LOONGSON_PCH_IRQ_BASE 64
+
+#define GSI_MIN_LPC_IRQ LOONGSON_LPC_IRQ_BASE
+#define GSI_MAX_LPC_IRQ (LOONGSON_LPC_IRQ_BASE + 16 - 1)
+#define GSI_MIN_CPU_IRQ LOONGSON_CPU_IRQ_BASE
+#define GSI_MAX_CPU_IRQ (LOONGSON_CPU_IRQ_BASE + 48 - 1)
+#define GSI_MIN_PCH_IRQ LOONGSON_PCH_IRQ_BASE
+#define GSI_MAX_PCH_IRQ (LOONGSON_PCH_IRQ_BASE + 256 - 1)
+
+int liointc_acpi_init(struct irq_domain *parent, struct acpi_madt_lio_pic *acpi_liointc);
+int eiointc_acpi_init(struct irq_domain *parent, struct acpi_madt_eio_pic *acpi_eiointc);
+int htvec_acpi_init(struct irq_domain *parent, struct acpi_madt_ht_pic *acpi_htvec);
+int pch_lpc_acpi_init(struct irq_domain *parent, struct acpi_madt_lpc_pic *acpi_pchlpc);
+struct fwnode_handle *lpic_get_gsi_domain_id(u32 gsi);
+void init_vector_parent_group(void);
+void acpi_set_vector_parent(int node, struct irq_domain *parent);
+struct irq_domain *acpi_get_msi_parent(int index);
+struct irq_domain *acpi_get_pch_parent(int node);
+
+#endif /* _IRQ_LOONGARCH_PIC_COMMON_H */
--
1.8.3.1