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From:   Jianmin Lv <lvjianmin@loongson.cn>
To:     Thomas Gleixner <tglx@linutronix.de>, Marc Zyngier <maz@kernel.org>
Cc:     linux-kernel@vger.kernel.org, Hanjun Guo <guohanjun@huawei.com>,
        Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>,
        Jiaxun Yang <jiaxun.yang@flygoat.com>,
        Huacai Chen <chenhuacai@loongson.cn>
Subject: [PATCH V13 08/13] irqchip/loongson-htvec: Add ACPI init support
Date:   Mon, 27 Jun 2022 19:39:52 +0800
Message-Id: <1656329997-20524-9-git-send-email-lvjianmin@loongson.cn>
In-Reply-To: <1656329997-20524-1-git-send-email-lvjianmin@loongson.cn>
References: <1656329997-20524-1-git-send-email-lvjianmin@loongson.cn>
Precedence: bulk

From: Huacai Chen <chenhuacai@loongson.cn>

We are preparing to add new Loongson (based on LoongArch, not compatible
with old MIPS-based Loongson) support. LoongArch use ACPI other than DT
as its boot protocol, so add ACPI init support.

HTVECINTC stands for "HyperTransport Interrupts" that described in
Section 14.3 of "Loongson 3A5000 Processor Reference Manual". For more
information please refer Documentation/loongarch/irq-chip-model.rst.

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     |   2 +-
 drivers/irqchip/irq-loongson-htvec.c | 121 +++++++++++++++++++++++++----------
 2 files changed, 88 insertions(+), 35 deletions(-)

diff --git a/arch/loongarch/include/asm/irq.h b/arch/loongarch/include/asm/irq.h
index 367aa44..e1e9e04 100644
--- a/arch/loongarch/include/asm/irq.h
+++ b/arch/loongarch/include/asm/irq.h
@@ -110,7 +110,7 @@ struct irq_domain *liointc_acpi_init(struct irq_domain *parent,
 struct irq_domain *eiointc_acpi_init(struct irq_domain *parent,
 					struct acpi_madt_eio_pic *acpi_eiointc);
 
-struct irq_domain *htvec_acpi_init(struct irq_domain *parent,
+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);
diff --git a/drivers/irqchip/irq-loongson-htvec.c b/drivers/irqchip/irq-loongson-htvec.c
index 60a335d..74e7896 100644
--- a/drivers/irqchip/irq-loongson-htvec.c
+++ b/drivers/irqchip/irq-loongson-htvec.c
@@ -20,7 +20,6 @@
 /* Registers */
 #define HTVEC_EN_OFF		0x20
 #define HTVEC_MAX_PARENT_IRQ	8
-
 #define VEC_COUNT_PER_REG	32
 #define VEC_REG_IDX(irq_id)	((irq_id) / VEC_COUNT_PER_REG)
 #define VEC_REG_BIT(irq_id)	((irq_id) % VEC_COUNT_PER_REG)
@@ -30,8 +29,11 @@ struct htvec {
 	void __iomem		*base;
 	struct irq_domain	*htvec_domain;
 	raw_spinlock_t		htvec_lock;
+	struct fwnode_handle	*domain_handle;
 };
 
+static struct htvec *htvec_priv;
+
 static void htvec_irq_dispatch(struct irq_desc *desc)
 {
 	int i;
@@ -155,64 +157,115 @@ static void htvec_reset(struct htvec *priv)
 	}
 }
 
-static int htvec_of_init(struct device_node *node,
-				struct device_node *parent)
+static int htvec_init(phys_addr_t addr, unsigned long size,
+		int num_parents, int parent_irq[], struct fwnode_handle *domain_handle)
 {
+	int i;
 	struct htvec *priv;
-	int err, parent_irq[8], i;
 
 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
 	if (!priv)
 		return -ENOMEM;
 
+	priv->num_parents = num_parents;
+	priv->base = ioremap(addr, size);
+	priv->domain_handle = domain_handle;
 	raw_spin_lock_init(&priv->htvec_lock);
-	priv->base = of_iomap(node, 0);
-	if (!priv->base) {
-		err = -ENOMEM;
-		goto free_priv;
-	}
-
-	/* Interrupt may come from any of the 8 interrupt lines */
-	for (i = 0; i < HTVEC_MAX_PARENT_IRQ; i++) {
-		parent_irq[i] = irq_of_parse_and_map(node, i);
-		if (parent_irq[i] <= 0)
-			break;
-
-		priv->num_parents++;
-	}
-
-	if (!priv->num_parents) {
-		pr_err("Failed to get parent irqs\n");
-		err = -ENODEV;
-		goto iounmap_base;
-	}
 
-	priv->htvec_domain = irq_domain_create_linear(of_node_to_fwnode(node),
+	/* Setup IRQ domain */
+	priv->htvec_domain = irq_domain_create_linear(priv->domain_handle,
 					(VEC_COUNT_PER_REG * priv->num_parents),
 					&htvec_domain_ops, priv);
 	if (!priv->htvec_domain) {
-		pr_err("Failed to create IRQ domain\n");
-		err = -ENOMEM;
-		goto irq_dispose;
+		pr_err("loongson-htvec: cannot add IRQ domain\n");
+		goto iounmap_base;
 	}
 
 	htvec_reset(priv);
 
-	for (i = 0; i < priv->num_parents; i++)
+	for (i = 0; i < priv->num_parents; i++) {
 		irq_set_chained_handler_and_data(parent_irq[i],
 						 htvec_irq_dispatch, priv);
+	}
+
+	htvec_priv = priv;
 
 	return 0;
 
-irq_dispose:
-	for (; i > 0; i--)
-		irq_dispose_mapping(parent_irq[i - 1]);
 iounmap_base:
 	iounmap(priv->base);
-free_priv:
+	priv->domain_handle = NULL;
 	kfree(priv);
 
-	return err;
+	return -EINVAL;
+}
+
+#ifdef CONFIG_OF
+
+static int htvec_of_init(struct device_node *node,
+				struct device_node *parent)
+{
+	int i, err;
+	int parent_irq[8];
+	int num_parents = 0;
+	struct resource res;
+
+	if (of_address_to_resource(node, 0, &res))
+		return -EINVAL;
+
+	/* Interrupt may come from any of the 8 interrupt lines */
+	for (i = 0; i < HTVEC_MAX_PARENT_IRQ; i++) {
+		parent_irq[i] = irq_of_parse_and_map(node, i);
+		if (parent_irq[i] <= 0)
+			break;
+
+		num_parents++;
+	}
+
+	err = htvec_init(res.start, resource_size(&res),
+			num_parents, parent_irq, of_node_to_fwnode(node));
+	if (err < 0)
+		return err;
+
+	return 0;
 }
 
 IRQCHIP_DECLARE(htvec, "loongson,htvec-1.0", htvec_of_init);
+
+#endif
+
+#ifdef CONFIG_ACPI
+int __init htvec_acpi_init(struct irq_domain *parent,
+				   struct acpi_madt_ht_pic *acpi_htvec)
+{
+	int i, ret;
+	int num_parents, parent_irq[8];
+	struct fwnode_handle *domain_handle;
+
+	if (!acpi_htvec)
+		return -EINVAL;
+
+	num_parents = HTVEC_MAX_PARENT_IRQ;
+
+	domain_handle = irq_domain_alloc_fwnode((phys_addr_t *)acpi_htvec);
+	if (!domain_handle) {
+		pr_err("Unable to allocate domain handle\n");
+		return -ENOMEM;
+	}
+
+	/* Interrupt may come from any of the 8 interrupt lines */
+	for (i = 0; i < HTVEC_MAX_PARENT_IRQ; i++)
+		parent_irq[i] = irq_create_mapping(parent, acpi_htvec->cascade[i]);
+
+	ret = htvec_init(acpi_htvec->address, acpi_htvec->size,
+			num_parents, parent_irq, domain_handle);
+	if (ret == 0) {
+		/* Only support single chipset system. */
+		msi_group[0].parent = htvec_priv->htvec_domain;
+		pch_group[0].parent = htvec_priv->htvec_domain;
+		pch_group[0].node = 0;
+	}
+	return ret;
+}
+
+#endif
-- 
1.8.3.1