[PATCH V10 04/10] irqchip/loongson-pch-msi: Add ACPI init support

From: Huacai Chen
Date: Sun Mar 06 2022 - 06:22:06 EST


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.

PCH-PIC/PCH-MSI stands for "Interrupt Controller" that described in
Section 5 of "Loongson 7A1000 Bridge User Manual". For more information
please refer Documentation/loongarch/irq-chip-model.rst.

Signed-off-by: Huacai Chen <chenhuacai@xxxxxxxxxxx>
---
drivers/irqchip/irq-loongson-pch-msi.c | 128 +++++++++++++++++--------
1 file changed, 86 insertions(+), 42 deletions(-)

diff --git a/drivers/irqchip/irq-loongson-pch-msi.c b/drivers/irqchip/irq-loongson-pch-msi.c
index e3801c4a77ed..6720212bece1 100644
--- a/drivers/irqchip/irq-loongson-pch-msi.c
+++ b/drivers/irqchip/irq-loongson-pch-msi.c
@@ -15,14 +15,19 @@
#include <linux/pci.h>
#include <linux/slab.h>

+static int nr_pics;
+
struct pch_msi_data {
struct mutex msi_map_lock;
phys_addr_t doorbell;
u32 irq_first; /* The vector number that MSIs starts */
u32 num_irqs; /* The number of vectors for MSIs */
unsigned long *msi_map;
+ struct fwnode_handle *domain_handle;
};

+static struct pch_msi_data *pch_msi_priv[2];
+
static void pch_msi_mask_msi_irq(struct irq_data *d)
{
pci_msi_mask_irq(d);
@@ -154,12 +159,14 @@ static const struct irq_domain_ops pch_msi_middle_domain_ops = {
};

static int pch_msi_init_domains(struct pch_msi_data *priv,
- struct device_node *node,
- struct irq_domain *parent)
+ struct irq_domain *parent,
+ struct fwnode_handle *domain_handle)
{
struct irq_domain *middle_domain, *msi_domain;

- middle_domain = irq_domain_create_linear(of_node_to_fwnode(node),
+ priv->domain_handle = domain_handle;
+
+ middle_domain = irq_domain_create_linear(priv->domain_handle,
priv->num_irqs,
&pch_msi_middle_domain_ops,
priv);
@@ -171,7 +178,7 @@ static int pch_msi_init_domains(struct pch_msi_data *priv,
middle_domain->parent = parent;
irq_domain_update_bus_token(middle_domain, DOMAIN_BUS_NEXUS);

- msi_domain = pci_msi_create_irq_domain(of_node_to_fwnode(node),
+ msi_domain = pci_msi_create_irq_domain(priv->domain_handle,
&pch_msi_domain_info,
middle_domain);
if (!msi_domain) {
@@ -183,19 +190,11 @@ static int pch_msi_init_domains(struct pch_msi_data *priv,
return 0;
}

-static int pch_msi_init(struct device_node *node,
- struct device_node *parent)
+static int pch_msi_init(phys_addr_t msg_address, int irq_base, int irq_count,
+ struct irq_domain *parent_domain, struct fwnode_handle *domain_handle)
{
- struct pch_msi_data *priv;
- struct irq_domain *parent_domain;
- struct resource res;
int ret;
-
- parent_domain = irq_find_host(parent);
- if (!parent_domain) {
- pr_err("Failed to find the parent domain\n");
- return -ENXIO;
- }
+ struct pch_msi_data *priv;

priv = kzalloc(sizeof(*priv), GFP_KERNEL);
if (!priv)
@@ -203,48 +202,93 @@ static int pch_msi_init(struct device_node *node,

mutex_init(&priv->msi_map_lock);

- ret = of_address_to_resource(node, 0, &res);
- if (ret) {
- pr_err("Failed to allocate resource\n");
- goto err_priv;
- }
-
- priv->doorbell = res.start;
-
- if (of_property_read_u32(node, "loongson,msi-base-vec",
- &priv->irq_first)) {
- pr_err("Unable to parse MSI vec base\n");
- ret = -EINVAL;
- goto err_priv;
- }
-
- if (of_property_read_u32(node, "loongson,msi-num-vecs",
- &priv->num_irqs)) {
- pr_err("Unable to parse MSI vec number\n");
- ret = -EINVAL;
- goto err_priv;
- }
+ priv->doorbell = msg_address;
+ priv->irq_first = irq_base;
+ priv->num_irqs = irq_count;

priv->msi_map = bitmap_zalloc(priv->num_irqs, GFP_KERNEL);
- if (!priv->msi_map) {
- ret = -ENOMEM;
+ if (!priv->msi_map)
goto err_priv;
- }

pr_debug("Registering %d MSIs, starting at %d\n",
priv->num_irqs, priv->irq_first);

- ret = pch_msi_init_domains(priv, node, parent_domain);
+ ret = pch_msi_init_domains(priv, parent_domain, domain_handle);
if (ret)
goto err_map;

+ pch_msi_priv[nr_pics++] = priv;
+
return 0;

err_map:
bitmap_free(priv->msi_map);
err_priv:
kfree(priv);
- return ret;
+
+ return -EINVAL;
+}
+
+#ifdef CONFIG_OF
+
+static int pch_msi_of_init(struct device_node *node, struct device_node *parent)
+{
+ int err;
+ int irq_base, irq_count;
+ struct resource res;
+ struct irq_domain *parent_domain;
+
+ parent_domain = irq_find_host(parent);
+ if (!parent_domain) {
+ pr_err("Failed to find the parent domain\n");
+ return -ENXIO;
+ }
+
+ if (of_address_to_resource(node, 0, &res)) {
+ pr_err("Failed to allocate resource\n");
+ return -EINVAL;
+ }
+
+ if (of_property_read_u32(node, "loongson,msi-base-vec", &irq_base)) {
+ pr_err("Unable to parse MSI vec base\n");
+ return -EINVAL;
+ }
+
+ if (of_property_read_u32(node, "loongson,msi-num-vecs", &irq_count)) {
+ pr_err("Unable to parse MSI vec number\n");
+ return -EINVAL;
+ }
+
+ err = pch_msi_init(res.start, irq_base, irq_count, parent_domain, of_node_to_fwnode(node));
+ if (err < 0)
+ return err;
+
+ return 0;
+}
+
+IRQCHIP_DECLARE(pch_msi, "loongson,pch-msi-1.0", pch_msi_of_init);
+
+#endif
+
+#ifdef CONFIG_ACPI
+
+struct irq_domain *pch_msi_acpi_init(struct irq_domain *parent,
+ struct acpi_madt_msi_pic *acpi_pchmsi)
+{
+ int ret;
+ struct fwnode_handle *domain_handle;
+
+ if (!acpi_pchmsi)
+ return NULL;
+
+ domain_handle = irq_domain_alloc_fwnode((phys_addr_t *)acpi_pchmsi);
+
+ ret = pch_msi_init(acpi_pchmsi->msg_address, acpi_pchmsi->start,
+ acpi_pchmsi->count, parent, domain_handle);
+ if (ret < 0)
+ return NULL;
+
+ return irq_find_matching_fwnode(domain_handle, DOMAIN_BUS_PCI_MSI);
}

-IRQCHIP_DECLARE(pch_msi, "loongson,pch-msi-1.0", pch_msi_init);
+#endif
--
2.27.0