2021-12-16 12:53:45

by Huacai Chen

[permalink] [raw]
Subject: [PATCH V8 00/10] irqchip: Add LoongArch-related irqchip drivers

LoongArch is a new RISC ISA, which is a bit like MIPS or RISC-V.
LoongArch includes a reduced 32-bit version (LA32R), a standard 32-bit
version (LA32S) and a 64-bit version (LA64). LoongArch use ACPI as its
boot protocol LoongArch-specific interrupt controllers (similar to APIC)
are already added in the next revision of ACPI Specification (current
revision is 6.4).

Currently, LoongArch based processors (e.g. Loongson-3A5000) can only
work together with LS7A chipsets. The irq chips in LoongArch computers
include CPUINTC (CPU Core Interrupt Controller), LIOINTC (Legacy I/O
Interrupt Controller), EIOINTC (Extended I/O Interrupt Controller),
HTVECINTC (Hyper-Transport Vector Interrupt Controller), PCH-PIC (Main
Interrupt Controller in LS7A chipset), PCH-LPC (LPC Interrupt Controller
in LS7A chipset) and PCH-MSI (MSI Interrupt Controller).

CPUINTC is a per-core controller (in CPU), LIOINTC/EIOINTC/HTVECINTC are
per-package controllers (in CPU), while PCH-PIC/PCH-LPC/PCH-MSI are all
controllers out of CPU (i.e., in chipsets). These controllers (in other
words, irqchips) are linked in a hierarchy, and there are two models of
hierarchy (legacy model and extended model).

Legacy IRQ model:

In this model, the IPI (Inter-Processor Interrupt) and CPU Local Timer
interrupt go to CPUINTC directly, CPU UARTS interrupts go to LIOINTC,
while all other devices interrupts go to PCH-PIC/PCH-LPC/PCH-MSI and
gathered by HTVECINTC, and then go to LIOINTC, and then CPUINTC.

+---------------------------------------------+
| |
| +-----+ +---------+ +-------+ |
| | IPI | --> | CPUINTC | <-- | Timer | |
| +-----+ +---------+ +-------+ |
| ^ |
| | |
| +---------+ +-------+ |
| | LIOINTC | <-- | UARTs | |
| +---------+ +-------+ |
| ^ |
| | |
| +-----------+ |
| | HTVECINTC | |
| +-----------+ |
| ^ ^ |
| | | |
| +---------+ +---------+ |
| | PCH-PIC | | PCH-MSI | |
| +---------+ +---------+ |
| ^ ^ ^ |
| | | | |
| +---------+ +---------+ +---------+ |
| | PCH-LPC | | Devices | | Devices | |
| +---------+ +---------+ +---------+ |
| ^ |
| | |
| +---------+ |
| | Devices | |
| +---------+ |
| |
| |
+---------------------------------------------+

Extended IRQ model:

In this model, the IPI (Inter-Processor Interrupt) and CPU Local Timer
interrupt go to CPUINTC directly, CPU UARTS interrupts go to LIOINTC,
while all other devices interrupts go to PCH-PIC/PCH-LPC/PCH-MSI and
gathered by EIOINTC, and then go to to CPUINTC directly.

+--------------------------------------------------------+
| |
| +-----+ +---------+ +-------+ |
| | IPI | --> | CPUINTC | <-- | Timer | |
| +-----+ +---------+ +-------+ |
| ^ ^ |
| | | |
| +---------+ +---------+ +-------+ |
| | EIOINTC | | LIOINTC | <-- | UARTs | |
| +---------+ +---------+ +-------+ |
| ^ ^ |
| | | |
| +---------+ +---------+ |
| | PCH-PIC | | PCH-MSI | |
| +---------+ +---------+ |
| ^ ^ ^ |
| | | | |
| +---------+ +---------+ +---------+ |
| | PCH-LPC | | Devices | | Devices | |
| +---------+ +---------+ +---------+ |
| ^ |
| | |
| +---------+ |
| | Devices | |
| +---------+ |
| |
| |
+--------------------------------------------------------+

This patchset adds some irqchip drivers for LoongArch, it is preparing
to add LoongArch support in mainline kernel, we can see a snapshot here:
https://github.com/loongson/linux/tree/loongarch-next

Cross-compile tool chain to build kernel:
https://github.com/loongson/build-tools/releases/latest/download/loongarch64-clfs-20211202-cross-tools.tar.xz

A CLFS-based Linux distro:
https://github.com/loongson/build-tools/releases/latest/download/loongarch64-clfs-system-2021-12-02.tar.bz2

Loongson and LoongArch documentations:
https://github.com/loongson/LoongArch-Documentation

LoongArch-specific interrupt controllers:
https://mantis.uefi.org/mantis/view.php?id=2203

LoongArch use ACPI, but ACPI tables cannot describe the hierarchy of
irqchips, so we initilize the irqchip subsystem in this way (from arch
code):

cpu_domain = loongarch_cpu_irq_init();
liointc_domain = liointc_acpi_init(cpu_domain, acpi_liointc);
eiointc_domain = eiointc_acpi_init(cpu_domain, acpi_eiointc);
pch_pic_domain = pch_pic_acpi_init(eiointc_domain, acpi_pchpic);
pch_msi_domain = pch_msi_acpi_init(eiointc_domain, acpi_pchmsi);

Upstream irqchip init function return an irqdomain, and this domain
will be used by downstream irqchips as their parent domains. For more
infomation please refer:
https://lore.kernel.org/linux-arch/[email protected]/T/#u

Attention: CPUINTC is CSR.ECFG/CSR.ESTAT and its interrupt controller
described in Section 7.4 of "LoongArch Reference Manual, Vol 1"; LIOINTC
is "Legacy I/O Interrupts" described in Section 11.1 of "Loongson 3A5000
Processor Reference Manual"; EIOINTC is "Extended I/O Interrupts" described
in Section 11.2 of "Loongson 3A5000 Processor Reference Manual"; HTVECINTC
is "HyperTransport Interrupts" described in Section 14.3 of "Loongson 3A5000
Processor Reference Manual"; PCH-PIC/PCH-MSI is "Interrupt Controller"
described in Section 5 of "Loongson 7A1000 Bridge User Manual"; PCH-LPC
is "LPC Interrupts" described in Section 24.3 of "Loongson 7A1000 Bridge
User Manual".

V1 -> V2:
1, Remove queued patches;
2, Move common logic of DT/ACPI probing to common functions;
3, Split .suspend()/.resume() functions to separate patches.

V2 -> V3:
1, Fix a bug for loongson-pch-pic probe;
2, Some minor improvements for LPC controller.

V3 -> V4:
1, Rework the CPU interrupt controller driver;
2, Some minor improvements for other controllers.

V4 -> V5:
1, Add a description of LoonArch's IRQ model;
2, Support multiple EIOINTCs in one system;
3, Some minor improvements for other controllers.

V5 -> V6:
1, Attach a fwnode to CPUINTC irq domain;
2, Use raw spinlock instead of generic spinlock;
3, Improve the method of restoring EIOINTC state;
4, Update documentation, comments and commit messages.

V6 -> V7:
1, Fix build warnings reported by kernel test robot.

V7 -> V8:
1, Add arguments sanity checking for irqchip init functions;
2, Support Loongson-3C5000 (One NUMA Node includes 4 EIOINTC Node).

Huacai Chen:
irqchip: Adjust Kconfig for Loongson.
irqchip/loongson-pch-pic: Add ACPI init support.
irqchip/loongson-pch-pic: Add suspend/resume support.
irqchip/loongson-pch-msi: Add ACPI init support.
irqchip/loongson-htvec: Add ACPI init support.
irqchip/loongson-htvec: Add suspend/resume support.
irqchip/loongson-liointc: Add ACPI init support.
irqchip: Add LoongArch CPU interrupt controller support.
irqchip: Add Loongson Extended I/O interrupt controller.
irqchip: Add Loongson PCH LPC controller support.

Signed-off-by: Huacai Chen <[email protected]>
---
drivers/irqchip/Kconfig | 37 +++-
drivers/irqchip/Makefile | 3 +
drivers/irqchip/irq-loongarch-cpu.c | 89 +++++++++
drivers/irqchip/irq-loongson-eiointc.c | 331 +++++++++++++++++++++++++++++++++
drivers/irqchip/irq-loongson-htvec.c | 142 ++++++++++----
drivers/irqchip/irq-loongson-liointc.c | 198 ++++++++++++--------
drivers/irqchip/irq-loongson-pch-lpc.c | 203 ++++++++++++++++++++
drivers/irqchip/irq-loongson-pch-msi.c | 119 +++++++-----
drivers/irqchip/irq-loongson-pch-pic.c | 152 ++++++++++++---
include/linux/cpuhotplug.h | 1 +
10 files changed, 1087 insertions(+), 188 deletions(-)
create mode 100644 drivers/irqchip/irq-loongarch-cpu.c
create mode 100644 drivers/irqchip/irq-loongson-eiointc.c
create mode 100644 drivers/irqchip/irq-loongson-pch-lpc.c
--
2.27.0



2021-12-16 12:55:45

by Huacai Chen

[permalink] [raw]
Subject: [PATCH V8 01/10] irqchip: Adjust Kconfig for Loongson

We are preparing to add new Loongson (based on LoongArch, not compatible
with old MIPS-based Loongson) support. HTVEC will be shared by both old
and new Loongson processors, so we adjust its description. HTPIC is only
used by MIPS-based Loongson, so we add a MIPS dependency. PCH_PIC and
PCH_MSI will have some arch-specific code, so we remove the COMPILE_TEST
dependency to avoid build warnings.

Signed-off-by: Huacai Chen <[email protected]>
---
drivers/irqchip/Kconfig | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index 7038957f4a77..139aa10e0b80 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -547,7 +547,7 @@ config LOONGSON_LIOINTC

config LOONGSON_HTPIC
bool "Loongson3 HyperTransport PIC Controller"
- depends on MACH_LOONGSON64
+ depends on (MACH_LOONGSON64 && MIPS)
default y
select IRQ_DOMAIN
select GENERIC_IRQ_CHIP
@@ -555,16 +555,16 @@ config LOONGSON_HTPIC
Support for the Loongson-3 HyperTransport PIC Controller.

config LOONGSON_HTVEC
- bool "Loongson3 HyperTransport Interrupt Vector Controller"
+ bool "Loongson HyperTransport Interrupt Vector Controller"
depends on MACH_LOONGSON64
default MACH_LOONGSON64
select IRQ_DOMAIN_HIERARCHY
help
- Support for the Loongson3 HyperTransport Interrupt Vector Controller.
+ Support for the Loongson HyperTransport Interrupt Vector Controller.

config LOONGSON_PCH_PIC
bool "Loongson PCH PIC Controller"
- depends on MACH_LOONGSON64 || COMPILE_TEST
+ depends on MACH_LOONGSON64
default MACH_LOONGSON64
select IRQ_DOMAIN_HIERARCHY
select IRQ_FASTEOI_HIERARCHY_HANDLERS
@@ -573,7 +573,7 @@ config LOONGSON_PCH_PIC

config LOONGSON_PCH_MSI
bool "Loongson PCH MSI Controller"
- depends on MACH_LOONGSON64 || COMPILE_TEST
+ depends on MACH_LOONGSON64
depends on PCI
default MACH_LOONGSON64
select IRQ_DOMAIN_HIERARCHY
--
2.27.0


2021-12-16 12:56:15

by Huacai Chen

[permalink] [raw]
Subject: [PATCH V8 02/10] irqchip/loongson-pch-pic: Add ACPI init support

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 <[email protected]>
---
drivers/irqchip/irq-loongson-pch-pic.c | 108 ++++++++++++++++++-------
1 file changed, 81 insertions(+), 27 deletions(-)

diff --git a/drivers/irqchip/irq-loongson-pch-pic.c b/drivers/irqchip/irq-loongson-pch-pic.c
index a4eb8a2181c7..b0644d595789 100644
--- a/drivers/irqchip/irq-loongson-pch-pic.c
+++ b/drivers/irqchip/irq-loongson-pch-pic.c
@@ -33,13 +33,18 @@
#define PIC_REG_IDX(irq_id) ((irq_id) / PIC_COUNT_PER_REG)
#define PIC_REG_BIT(irq_id) ((irq_id) % PIC_COUNT_PER_REG)

+static int nr_pics;
+
struct pch_pic {
void __iomem *base;
struct irq_domain *pic_domain;
+ struct fwnode_handle *domain_handle;
u32 ht_vec_base;
raw_spinlock_t pic_lock;
};

+static struct pch_pic *pch_pic_priv[2];
+
static void pch_pic_bitset(struct pch_pic *priv, int offset, int bit)
{
u32 reg;
@@ -180,7 +185,7 @@ static void pch_pic_reset(struct pch_pic *priv)
int i;

for (i = 0; i < PIC_COUNT; i++) {
- /* Write vectored ID */
+ /* Write vector ID */
writeb(priv->ht_vec_base + i, priv->base + PCH_INT_HTVEC(i));
/* Hardcode route to HT0 Lo */
writeb(1, priv->base + PCH_INT_ROUTE(i));
@@ -198,50 +203,37 @@ static void pch_pic_reset(struct pch_pic *priv)
}
}

-static int pch_pic_of_init(struct device_node *node,
- struct device_node *parent)
+static int pch_pic_init(phys_addr_t addr, unsigned long size, int vec_base,
+ struct irq_domain *parent_domain, struct fwnode_handle *domain_handle)
{
+ int vec_count;
struct pch_pic *priv;
- struct irq_domain *parent_domain;
- int err;

priv = kzalloc(sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;

raw_spin_lock_init(&priv->pic_lock);
- priv->base = of_iomap(node, 0);
- if (!priv->base) {
- err = -ENOMEM;
+ priv->base = ioremap(addr, size);
+ if (!priv->base)
goto free_priv;
- }

- parent_domain = irq_find_host(parent);
- if (!parent_domain) {
- pr_err("Failed to find the parent domain\n");
- err = -ENXIO;
- goto iounmap_base;
- }
+ priv->domain_handle = domain_handle;

- if (of_property_read_u32(node, "loongson,pic-base-vec",
- &priv->ht_vec_base)) {
- pr_err("Failed to determine pic-base-vec\n");
- err = -EINVAL;
- goto iounmap_base;
- }
+ priv->ht_vec_base = vec_base;
+ vec_count = ((readq(priv->base) >> 48) & 0xff) + 1;

priv->pic_domain = irq_domain_create_hierarchy(parent_domain, 0,
- PIC_COUNT,
- of_node_to_fwnode(node),
- &pch_pic_domain_ops,
- priv);
+ vec_count, priv->domain_handle,
+ &pch_pic_domain_ops, priv);
+
if (!priv->pic_domain) {
pr_err("Failed to create IRQ domain\n");
- err = -ENOMEM;
goto iounmap_base;
}

pch_pic_reset(priv);
+ pch_pic_priv[nr_pics++] = priv;

return 0;

@@ -250,7 +242,69 @@ static int pch_pic_of_init(struct device_node *node,
free_priv:
kfree(priv);

- return err;
+ return -EINVAL;
+}
+
+#ifdef CONFIG_OF
+
+static int pch_pic_of_init(struct device_node *node,
+ struct device_node *parent)
+{
+ int err, vec_base;
+ struct resource res;
+ struct irq_domain *parent_domain;
+
+ if (of_address_to_resource(node, 0, &res))
+ return -EINVAL;
+
+ parent_domain = irq_find_host(parent);
+ if (!parent_domain) {
+ pr_err("Failed to find the parent domain\n");
+ return -ENXIO;
+ }
+
+ if (of_property_read_u32(node, "loongson,pic-base-vec", &vec_base)) {
+ pr_err("Failed to determine pic-base-vec\n");
+ return -EINVAL;
+ }
+
+ err = pch_pic_init(res.start, resource_size(&res), vec_base,
+ parent_domain, of_node_to_fwnode(node));
+ if (err < 0)
+ return err;
+
+ return 0;
}

IRQCHIP_DECLARE(pch_pic, "loongson,pch-pic-1.0", pch_pic_of_init);
+
+#endif
+
+#ifdef CONFIG_ACPI
+
+struct irq_domain *pch_pic_acpi_init(struct irq_domain *parent,
+ struct acpi_madt_bio_pic *acpi_pchpic)
+{
+ int ret, vec_base;
+ struct fwnode_handle *domain_handle;
+
+ if (!acpi_pchpic)
+ return NULL;
+
+ vec_base = acpi_pchpic->gsi_base - GSI_MIN_PCH_IRQ;
+
+ domain_handle = irq_domain_alloc_fwnode((phys_addr_t *)acpi_pchpic);
+ if (!domain_handle) {
+ pr_err("Unable to allocate domain handle\n");
+ return NULL;
+ }
+
+ ret = pch_pic_init(acpi_pchpic->address, acpi_pchpic->size,
+ vec_base, parent, domain_handle);
+ if (ret < 0)
+ return NULL;
+
+ return irq_find_matching_fwnode(domain_handle, DOMAIN_BUS_ANY);
+}
+
+#endif
--
2.27.0


2021-12-16 12:57:46

by Huacai Chen

[permalink] [raw]
Subject: [PATCH V8 03/10] irqchip/loongson-pch-pic: Add suspend/resume support

Add suspend/resume support for PCH-PIC irqchip, which is needed for
suspend/hibernation.

Signed-off-by: Huacai Chen <[email protected]>
---
drivers/irqchip/irq-loongson-pch-pic.c | 47 ++++++++++++++++++++++++++
1 file changed, 47 insertions(+)

diff --git a/drivers/irqchip/irq-loongson-pch-pic.c b/drivers/irqchip/irq-loongson-pch-pic.c
index b0644d595789..5047ba96f7d7 100644
--- a/drivers/irqchip/irq-loongson-pch-pic.c
+++ b/drivers/irqchip/irq-loongson-pch-pic.c
@@ -15,6 +15,7 @@
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/of_platform.h>
+#include <linux/syscore_ops.h>

/* Registers */
#define PCH_PIC_MASK 0x20
@@ -41,6 +42,9 @@ struct pch_pic {
struct fwnode_handle *domain_handle;
u32 ht_vec_base;
raw_spinlock_t pic_lock;
+ u32 saved_vec_en[PIC_REG_COUNT];
+ u32 saved_vec_pol[PIC_REG_COUNT];
+ u32 saved_vec_edge[PIC_REG_COUNT];
};

static struct pch_pic *pch_pic_priv[2];
@@ -142,6 +146,7 @@ static struct irq_chip pch_pic_irq_chip = {
.irq_ack = pch_pic_ack_irq,
.irq_set_affinity = irq_chip_set_affinity_parent,
.irq_set_type = pch_pic_set_type,
+ .flags = IRQCHIP_SKIP_SET_WAKE,
};

static int pch_pic_alloc(struct irq_domain *domain, unsigned int virq,
@@ -203,6 +208,46 @@ static void pch_pic_reset(struct pch_pic *priv)
}
}

+static int pch_pic_suspend(void)
+{
+ int i, j;
+
+ for (i = 0; i < nr_pics; i++) {
+ for (j = 0; j < PIC_REG_COUNT; j++) {
+ pch_pic_priv[i]->saved_vec_pol[j] =
+ readl(pch_pic_priv[i]->base + PCH_PIC_POL + 4 * j);
+ pch_pic_priv[i]->saved_vec_edge[j] =
+ readl(pch_pic_priv[i]->base + PCH_PIC_EDGE + 4 * j);
+ pch_pic_priv[i]->saved_vec_en[j] =
+ readl(pch_pic_priv[i]->base + PCH_PIC_MASK + 4 * j);
+ }
+ }
+
+ return 0;
+}
+
+static void pch_pic_resume(void)
+{
+ int i, j;
+
+ for (i = 0; i < nr_pics; i++) {
+ pch_pic_reset(pch_pic_priv[i]);
+ for (j = 0; j < PIC_REG_COUNT; j++) {
+ writel(pch_pic_priv[i]->saved_vec_pol[j],
+ pch_pic_priv[i]->base + PCH_PIC_POL + 4 * j);
+ writel(pch_pic_priv[i]->saved_vec_edge[j],
+ pch_pic_priv[i]->base + PCH_PIC_EDGE + 4 * j);
+ writel(pch_pic_priv[i]->saved_vec_en[j],
+ pch_pic_priv[i]->base + PCH_PIC_MASK + 4 * j);
+ }
+ }
+}
+
+static struct syscore_ops pch_pic_syscore_ops = {
+ .suspend = pch_pic_suspend,
+ .resume = pch_pic_resume,
+};
+
static int pch_pic_init(phys_addr_t addr, unsigned long size, int vec_base,
struct irq_domain *parent_domain, struct fwnode_handle *domain_handle)
{
@@ -235,6 +280,8 @@ static int pch_pic_init(phys_addr_t addr, unsigned long size, int vec_base,
pch_pic_reset(priv);
pch_pic_priv[nr_pics++] = priv;

+ register_syscore_ops(&pch_pic_syscore_ops);
+
return 0;

iounmap_base:
--
2.27.0


2021-12-16 12:58:52

by Huacai Chen

[permalink] [raw]
Subject: [PATCH V8 04/10] irqchip/loongson-pch-msi: Add ACPI init support

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 <[email protected]>
---
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 32562b7e681b..2baac5f03a83 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:
kfree(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


2021-12-16 12:59:42

by Huacai Chen

[permalink] [raw]
Subject: [PATCH V8 05/10] irqchip/loongson-htvec: Add ACPI init support

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.

Signed-off-by: Huacai Chen <[email protected]>
---
drivers/irqchip/irq-loongson-htvec.c | 118 +++++++++++++++++++--------
1 file changed, 84 insertions(+), 34 deletions(-)

diff --git a/drivers/irqchip/irq-loongson-htvec.c b/drivers/irqchip/irq-loongson-htvec.c
index 60a335d7e64e..8efb00c79b55 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 +157,112 @@ 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 num_parents, parent_irq[8];
+ 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
+
+struct irq_domain *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 NULL;
+
+ 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 NULL;
+ }
+
+ /* 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)
+ return NULL;
+
+ return irq_find_matching_fwnode(domain_handle, DOMAIN_BUS_ANY);
+}
+
+#endif
--
2.27.0


2021-12-16 13:01:50

by Huacai Chen

[permalink] [raw]
Subject: [PATCH V8 06/10] irqchip/loongson-htvec: Add suspend/resume support

Add suspend/resume support for HTVEC irqchip, which is needed for
suspend/hibernation.

Signed-off-by: Huacai Chen <[email protected]>
---
drivers/irqchip/irq-loongson-htvec.c | 27 +++++++++++++++++++++++++++
1 file changed, 27 insertions(+)

diff --git a/drivers/irqchip/irq-loongson-htvec.c b/drivers/irqchip/irq-loongson-htvec.c
index 8efb00c79b55..8c63165460f9 100644
--- a/drivers/irqchip/irq-loongson-htvec.c
+++ b/drivers/irqchip/irq-loongson-htvec.c
@@ -16,6 +16,7 @@
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/of_platform.h>
+#include <linux/syscore_ops.h>

/* Registers */
#define HTVEC_EN_OFF 0x20
@@ -30,6 +31,7 @@ struct htvec {
struct irq_domain *htvec_domain;
raw_spinlock_t htvec_lock;
struct fwnode_handle *domain_handle;
+ u32 saved_vec_en[HTVEC_MAX_PARENT_IRQ];
};

static struct htvec *htvec_priv;
@@ -157,6 +159,29 @@ static void htvec_reset(struct htvec *priv)
}
}

+static int htvec_suspend(void)
+{
+ int i;
+
+ for (i = 0; i < htvec_priv->num_parents; i++)
+ htvec_priv->saved_vec_en[i] = readl(htvec_priv->base + HTVEC_EN_OFF + 4 * i);
+
+ return 0;
+}
+
+static void htvec_resume(void)
+{
+ int i;
+
+ for (i = 0; i < htvec_priv->num_parents; i++)
+ writel(htvec_priv->saved_vec_en[i], htvec_priv->base + HTVEC_EN_OFF + 4 * i);
+}
+
+static struct syscore_ops htvec_syscore_ops = {
+ .suspend = htvec_suspend,
+ .resume = htvec_resume,
+};
+
static int htvec_init(phys_addr_t addr, unsigned long size,
int num_parents, int parent_irq[], struct fwnode_handle *domain_handle)
{
@@ -190,6 +215,8 @@ static int htvec_init(phys_addr_t addr, unsigned long size,

htvec_priv = priv;

+ register_syscore_ops(&htvec_syscore_ops);
+
return 0;

iounmap_base:
--
2.27.0


2021-12-16 13:02:09

by Huacai Chen

[permalink] [raw]
Subject: [PATCH V8 07/10] irqchip/loongson-liointc: Add ACPI init support

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.

LIOINTC stands for "Legacy I/O Interrupts" that described in Section
11.1 of "Loongson 3A5000 Processor Reference Manual". For more
information please refer Documentation/loongarch/irq-chip-model.rst.

Signed-off-by: Huacai Chen <[email protected]>
---
drivers/irqchip/irq-loongson-liointc.c | 204 +++++++++++++++----------
1 file changed, 125 insertions(+), 79 deletions(-)

diff --git a/drivers/irqchip/irq-loongson-liointc.c b/drivers/irqchip/irq-loongson-liointc.c
index 649c58391618..ff3cb5b05710 100644
--- a/drivers/irqchip/irq-loongson-liointc.c
+++ b/drivers/irqchip/irq-loongson-liointc.c
@@ -16,10 +16,14 @@
#include <linux/smp.h>
#include <linux/irqchip/chained_irq.h>

+#ifdef CONFIG_MIPS
#include <loongson.h>
+#else
+#include <asm/loongson.h>
+#endif

#define LIOINTC_CHIP_IRQ 32
-#define LIOINTC_NUM_PARENT 4
+#define LIOINTC_NUM_PARENT 4
#define LIOINTC_NUM_CORES 4

#define LIOINTC_INTC_CHIP_START 0x20
@@ -41,6 +45,7 @@ struct liointc_handler_data {
};

struct liointc_priv {
+ struct fwnode_handle *domain_handle;
struct irq_chip_generic *gc;
struct liointc_handler_data handler[LIOINTC_NUM_PARENT];
void __iomem *core_isr[LIOINTC_NUM_CORES];
@@ -53,7 +58,7 @@ static void liointc_chained_handle_irq(struct irq_desc *desc)
struct liointc_handler_data *handler = irq_desc_get_handler_data(desc);
struct irq_chip *chip = irq_desc_get_chip(desc);
struct irq_chip_generic *gc = handler->priv->gc;
- int core = get_ebase_cpunum() % LIOINTC_NUM_CORES;
+ int core = cpu_logical_map(smp_processor_id()) % LIOINTC_NUM_CORES;
u32 pending;

chained_irq_enter(chip, desc);
@@ -143,97 +148,62 @@ static void liointc_resume(struct irq_chip_generic *gc)
irq_gc_unlock_irqrestore(gc, flags);
}

-static const char * const parent_names[] = {"int0", "int1", "int2", "int3"};
-static const char * const core_reg_names[] = {"isr0", "isr1", "isr2", "isr3"};
+static int parent_irq[LIOINTC_NUM_PARENT];
+static u32 parent_int_map[LIOINTC_NUM_PARENT];
+static const char *const parent_names[] = {"int0", "int1", "int2", "int3"};
+static const char *const core_reg_names[] = {"isr0", "isr1", "isr2", "isr3"};

-static void __iomem *liointc_get_reg_byname(struct device_node *node,
- const char *name)
-{
- int index = of_property_match_string(node, "reg-names", name);
-
- if (index < 0)
- return NULL;
-
- return of_iomap(node, index);
-}
-
-static int __init liointc_of_init(struct device_node *node,
- struct device_node *parent)
+static int liointc_init(phys_addr_t addr, unsigned long size, int revision,
+ struct fwnode_handle *domain_handle, struct device_node *node)
{
+ int i, err;
+ void __iomem *base;
+ struct irq_chip_type *ct;
struct irq_chip_generic *gc;
struct irq_domain *domain;
- struct irq_chip_type *ct;
struct liointc_priv *priv;
- void __iomem *base;
- u32 of_parent_int_map[LIOINTC_NUM_PARENT];
- int parent_irq[LIOINTC_NUM_PARENT];
- bool have_parent = FALSE;
- int sz, i, err = 0;

priv = kzalloc(sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;

- if (of_device_is_compatible(node, "loongson,liointc-2.0")) {
- base = liointc_get_reg_byname(node, "main");
- if (!base) {
- err = -ENODEV;
- goto out_free_priv;
- }
+ base = ioremap(addr, size);
+ if (!base)
+ goto out_free_priv;

- for (i = 0; i < LIOINTC_NUM_CORES; i++)
- priv->core_isr[i] = liointc_get_reg_byname(node, core_reg_names[i]);
- if (!priv->core_isr[0]) {
- err = -ENODEV;
- goto out_iounmap_base;
- }
- } else {
- base = of_iomap(node, 0);
- if (!base) {
- err = -ENODEV;
- goto out_free_priv;
- }
+ priv->domain_handle = domain_handle;

- for (i = 0; i < LIOINTC_NUM_CORES; i++)
- priv->core_isr[i] = base + LIOINTC_REG_INTC_STATUS;
- }
+ for (i = 0; i < LIOINTC_NUM_CORES; i++)
+ priv->core_isr[i] = base + LIOINTC_REG_INTC_STATUS;

- for (i = 0; i < LIOINTC_NUM_PARENT; i++) {
- parent_irq[i] = of_irq_get_byname(node, parent_names[i]);
- if (parent_irq[i] > 0)
- have_parent = TRUE;
- }
- if (!have_parent) {
- err = -ENODEV;
- goto out_iounmap_isr;
- }
+ for (i = 0; i < LIOINTC_NUM_PARENT; i++)
+ priv->handler[i].parent_int_map = parent_int_map[i];

- sz = of_property_read_variable_u32_array(node,
- "loongson,parent_int_map",
- &of_parent_int_map[0],
- LIOINTC_NUM_PARENT,
- LIOINTC_NUM_PARENT);
- if (sz < 4) {
- pr_err("loongson-liointc: No parent_int_map\n");
- err = -ENODEV;
- goto out_iounmap_isr;
- }
+#ifdef CONFIG_OF
+ if (revision > 1) {
+ for (i = 0; i < LIOINTC_NUM_CORES; i++) {
+ int index = of_property_match_string(node,
+ "reg-names", core_reg_names[i]);

- for (i = 0; i < LIOINTC_NUM_PARENT; i++)
- priv->handler[i].parent_int_map = of_parent_int_map[i];
+ if (index < 0)
+ return -EINVAL;
+
+ priv->core_isr[i] = of_iomap(node, index);
+ }
+ }
+#endif

/* Setup IRQ domain */
- domain = irq_domain_add_linear(node, 32,
+ domain = irq_domain_create_linear(domain_handle, LIOINTC_CHIP_IRQ,
&irq_generic_chip_ops, priv);
if (!domain) {
pr_err("loongson-liointc: cannot add IRQ domain\n");
- err = -EINVAL;
- goto out_iounmap_isr;
+ goto out_iounmap;
}

- err = irq_alloc_domain_generic_chips(domain, 32, 1,
- node->full_name, handle_level_irq,
- IRQ_NOPROBE, 0, 0);
+ err = irq_alloc_domain_generic_chips(domain, LIOINTC_CHIP_IRQ, 1,
+ (node ? node->full_name : "LIOINTC"),
+ handle_level_irq, 0, IRQ_NOPROBE, 0);
if (err) {
pr_err("loongson-liointc: unable to register IRQ domain\n");
goto out_free_domain;
@@ -293,20 +263,96 @@ static int __init liointc_of_init(struct device_node *node,

out_free_domain:
irq_domain_remove(domain);
-out_iounmap_isr:
- for (i = 0; i < LIOINTC_NUM_CORES; i++) {
- if (!priv->core_isr[i])
- continue;
- iounmap(priv->core_isr[i]);
- }
-out_iounmap_base:
+out_iounmap:
iounmap(base);
out_free_priv:
kfree(priv);

- return err;
+ return -EINVAL;
+}
+
+#ifdef CONFIG_OF
+
+static int __init liointc_of_init(struct device_node *node,
+ struct device_node *parent)
+{
+ bool have_parent = FALSE;
+ int sz, i, index, revision, err = 0;
+ struct resource res;
+
+ if (!of_device_is_compatible(node, "loongson,liointc-2.0")) {
+ index = 0;
+ revision = 1;
+ } else {
+ index = of_property_match_string(node, "reg-names", "main");
+ revision = 2;
+ }
+
+ if (of_address_to_resource(node, index, &res))
+ return -EINVAL;
+
+ for (i = 0; i < LIOINTC_NUM_PARENT; i++) {
+ parent_irq[i] = of_irq_get_byname(node, parent_names[i]);
+ if (parent_irq[i] > 0)
+ have_parent = TRUE;
+ }
+ if (!have_parent)
+ return -ENODEV;
+
+ sz = of_property_read_variable_u32_array(node,
+ "loongson,parent_int_map",
+ &parent_int_map[0],
+ LIOINTC_NUM_PARENT,
+ LIOINTC_NUM_PARENT);
+ if (sz < 4) {
+ pr_err("loongson-liointc: No parent_int_map\n");
+ return -ENODEV;
+ }
+
+ err = liointc_init(res.start, resource_size(&res),
+ revision, of_node_to_fwnode(node), node);
+ if (err < 0)
+ return err;
+
+ return 0;
}

IRQCHIP_DECLARE(loongson_liointc_1_0, "loongson,liointc-1.0", liointc_of_init);
IRQCHIP_DECLARE(loongson_liointc_1_0a, "loongson,liointc-1.0a", liointc_of_init);
IRQCHIP_DECLARE(loongson_liointc_2_0, "loongson,liointc-2.0", liointc_of_init);
+
+#endif
+
+#ifdef CONFIG_ACPI
+
+struct irq_domain *liointc_acpi_init(struct irq_domain *parent,
+ struct acpi_madt_lio_pic *acpi_liointc)
+{
+ int ret;
+ struct fwnode_handle *domain_handle;
+
+ if (!acpi_liointc)
+ return NULL;
+
+ parent_int_map[0] = acpi_liointc->cascade_map[0];
+ parent_int_map[1] = acpi_liointc->cascade_map[1];
+
+ parent_irq[0] = irq_create_mapping(parent, acpi_liointc->cascade[0]);
+ if (!cpu_has_extioi)
+ parent_irq[1] = irq_create_mapping(parent, acpi_liointc->cascade[1]);
+
+ domain_handle = irq_domain_alloc_fwnode((phys_addr_t *)acpi_liointc);
+ if (!domain_handle) {
+ pr_err("Unable to allocate domain handle\n");
+ return NULL;
+ }
+
+ ret = liointc_init(acpi_liointc->address, acpi_liointc->size,
+ 1, domain_handle, NULL);
+ if (ret < 0)
+ return NULL;
+
+ return irq_find_matching_fwnode(domain_handle, DOMAIN_BUS_ANY);
+}
+
+#endif
--
2.27.0


2021-12-16 13:04:15

by Huacai Chen

[permalink] [raw]
Subject: [PATCH V8 08/10] irqchip: Add LoongArch CPU interrupt controller support

We are preparing to add new Loongson (based on LoongArch, not compatible
with old MIPS-based Loongson) support. This patch add the LoongArch CPU
interrupt controller support.

LoongArch CPUINTC stands for CSR.ECFG/CSR.ESTAT and related interrupt
controller that described in Section 7.4 of "LoongArch Reference Manual,
Vol 1". For more information please refer Documentation/loongarch/irq-
chip-model.rst.

LoongArch CPUINTC has 13 interrupt sources: SWI0~1, HWI0~7, IPI, TI
(Timer) and PCOV (PMC). IRQ mappings of HWI0~7 are configurable (can be
created from DT/ACPI), but IPI, TI (Timer) and PCOV (PMC) are hardcoded
bits, so we define get_xxx_irq() for them.

Signed-off-by: Huacai Chen <[email protected]>
---
drivers/irqchip/Kconfig | 10 ++++
drivers/irqchip/Makefile | 1 +
drivers/irqchip/irq-loongarch-cpu.c | 92 +++++++++++++++++++++++++++++
3 files changed, 103 insertions(+)
create mode 100644 drivers/irqchip/irq-loongarch-cpu.c

diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index 139aa10e0b80..a7fe97dcac8d 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -536,6 +536,16 @@ config EXYNOS_IRQ_COMBINER
Say yes here to add support for the IRQ combiner devices embedded
in Samsung Exynos chips.

+config IRQ_LOONGARCH_CPU
+ bool
+ select GENERIC_IRQ_CHIP
+ select IRQ_DOMAIN
+ select GENERIC_IRQ_EFFECTIVE_AFF_MASK
+ help
+ Support for the LoongArch CPU Interrupt Controller. For details of
+ irq chip hierarchy on LoongArch platforms please read the document
+ Documentation/loongarch/irq-chip-model.rst.
+
config LOONGSON_LIOINTC
bool "Loongson Local I/O Interrupt Controller"
depends on MACH_LOONGSON64
diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
index c1f611cbfbf8..42724fc51103 100644
--- a/drivers/irqchip/Makefile
+++ b/drivers/irqchip/Makefile
@@ -105,6 +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_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-cpu.c b/drivers/irqchip/irq-loongarch-cpu.c
new file mode 100644
index 000000000000..e05638bd668c
--- /dev/null
+++ b/drivers/irqchip/irq-loongarch-cpu.c
@@ -0,0 +1,92 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2020-2021 Loongson Technology Corporation Limited
+ */
+
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/irqchip.h>
+#include <linux/irqdomain.h>
+
+#include <asm/loongarch.h>
+#include <asm/setup.h>
+
+static struct irq_domain *irq_domain;
+
+static void mask_loongarch_irq(struct irq_data *d)
+{
+ clear_csr_ecfg(ECFGF(d->hwirq));
+}
+
+static void unmask_loongarch_irq(struct irq_data *d)
+{
+ set_csr_ecfg(ECFGF(d->hwirq));
+}
+
+static struct irq_chip cpu_irq_controller = {
+ .name = "LoongArch",
+ .irq_mask = mask_loongarch_irq,
+ .irq_unmask = unmask_loongarch_irq,
+};
+
+static void handle_cpu_irq(struct pt_regs *regs)
+{
+ int hwirq;
+ unsigned int estat = read_csr_estat() & CSR_ESTAT_IS;
+
+ while ((hwirq = ffs(estat))) {
+ estat &= ~BIT(hwirq - 1);
+ generic_handle_domain_irq(irq_domain, hwirq - 1);
+ }
+}
+
+int get_ipi_irq(void)
+{
+ return irq_create_mapping(irq_domain, EXCCODE_IPI - EXCCODE_INT_START);
+}
+
+int get_pmc_irq(void)
+{
+ return irq_create_mapping(irq_domain, EXCCODE_PMC - EXCCODE_INT_START);
+}
+
+int get_timer_irq(void)
+{
+ return irq_create_mapping(irq_domain, EXCCODE_TIMER - EXCCODE_INT_START);
+}
+
+static int loongarch_cpu_intc_map(struct irq_domain *d, unsigned int irq,
+ irq_hw_number_t hwirq)
+{
+ irq_set_noprobe(irq);
+ irq_set_chip_and_handler(irq, &cpu_irq_controller, handle_percpu_irq);
+
+ return 0;
+}
+
+static const struct irq_domain_ops loongarch_cpu_intc_irq_domain_ops = {
+ .map = loongarch_cpu_intc_map,
+ .xlate = irq_domain_xlate_onecell,
+};
+
+struct irq_domain * __init loongarch_cpu_irq_init(void)
+{
+ struct fwnode_handle *domain_handle;
+
+ /* Mask interrupts. */
+ clear_csr_ecfg(ECFG0_IM);
+ clear_csr_estat(ESTATF_IP);
+
+ domain_handle = irq_domain_alloc_fwnode(NULL);
+ irq_domain = irq_domain_create_linear(domain_handle, EXCCODE_INT_NUM,
+ &loongarch_cpu_intc_irq_domain_ops, NULL);
+
+ if (!irq_domain)
+ panic("Failed to add irqdomain for LoongArch CPU");
+
+ set_handle_irq(&handle_cpu_irq);
+
+ return irq_domain;
+}
--
2.27.0


2021-12-16 13:05:45

by Huacai Chen

[permalink] [raw]
Subject: [PATCH V8 09/10] irqchip: Add Loongson Extended I/O interrupt controller support

We are preparing to add new Loongson (based on LoongArch, not compatible
with old MIPS-based Loongson) support. This patch add Loongson Extended
I/O CPU interrupt controller support.

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).

Signed-off-by: Huacai Chen <[email protected]>
---
drivers/irqchip/Kconfig | 10 +
drivers/irqchip/Makefile | 1 +
drivers/irqchip/irq-loongson-eiointc.c | 372 +++++++++++++++++++++++++
include/linux/cpuhotplug.h | 1 +
4 files changed, 384 insertions(+)
create mode 100644 drivers/irqchip/irq-loongson-eiointc.c

diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index a7fe97dcac8d..a785495df3d9 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 42724fc51103..2a5dc2b5f737 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..5e7338367ab1
--- /dev/null
+++ b/drivers/irqchip/irq-loongson-eiointc.c
@@ -0,0 +1,372 @@
+// 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)
+#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[2];
+
+int eiointc_get_node(int id)
+{
+ return eiointc_priv[id]->node;
+}
+
+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_writel(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_writel(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_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 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 int eiointc_suspend(void)
+{
+ return 0;
+}
+
+static void eiointc_resume(void)
+{
+ int i, j;
+ struct irq_desc *desc;
+ struct irq_data *irq_data;
+
+ eiointc_router_init(0);
+
+ for (i = 0; i < nr_pics; i++) {
+ for (j = 0; j < VEC_COUNT; j++) {
+ desc = irq_resolve_mapping(eiointc_priv[i]->eiointc_domain, j);
+ if (desc && desc->handle_irq && desc->handle_irq != handle_bad_irq) {
+ irq_data = &desc->irq_data;
+ 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 irq_domain *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 NULL;
+
+ 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;
+ }
+
+ 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_priv;
+ }
+
+ 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);
+
+ register_syscore_ops(&eiointc_syscore_ops);
+ cpuhp_setup_state_nocalls(CPUHP_AP_IRQ_LOONGARCH_STARTING,
+ "irqchip/loongarch/intc:starting",
+ eiointc_router_init, NULL);
+
+ return irq_find_matching_fwnode(priv->domain_handle, DOMAIN_BUS_ANY);
+
+out_free_priv:
+ priv->domain_handle = NULL;
+ kfree(priv);
+
+ return NULL;
+}
diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h
index 773c83730906..6c77987a3bce 100644
--- a/include/linux/cpuhotplug.h
+++ b/include/linux/cpuhotplug.h
@@ -149,6 +149,7 @@ 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


2021-12-16 13:07:18

by Huacai Chen

[permalink] [raw]
Subject: [PATCH V8 10/10] irqchip: Add Loongson PCH LPC controller support

We are preparing to add new Loongson (based on LoongArch, not compatible
with old MIPS-based Loongson) support. This patch add Loongson PCH LPC
interrupt controller support.

PCH-LPC stands for "LPC Interrupts" that described in Section 24.3 of
"Loongson 7A1000 Bridge User Manual". For more information please refer
Documentation/loongarch/irq-chip-model.rst.

Signed-off-by: Huacai Chen <[email protected]>
---
drivers/irqchip/Kconfig | 8 +
drivers/irqchip/Makefile | 1 +
drivers/irqchip/irq-loongson-pch-lpc.c | 204 +++++++++++++++++++++++++
3 files changed, 213 insertions(+)
create mode 100644 drivers/irqchip/irq-loongson-pch-lpc.c

diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index a785495df3d9..4a3de7478a61 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -601,6 +601,14 @@ config LOONGSON_PCH_MSI
help
Support for the Loongson PCH MSI Controller.

+config LOONGSON_PCH_LPC
+ bool "Loongson PCH LPC Controller"
+ depends on MACH_LOONGSON64
+ default (MACH_LOONGSON64 && LOONGARCH)
+ select IRQ_DOMAIN_HIERARCHY
+ help
+ Support for the Loongson PCH LPC Controller.
+
config MST_IRQ
bool "MStar Interrupt Controller"
depends on ARCH_MEDIATEK || ARCH_MSTARV7 || COMPILE_TEST
diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
index 2a5dc2b5f737..c30bf08bcbcd 100644
--- a/drivers/irqchip/Makefile
+++ b/drivers/irqchip/Makefile
@@ -112,6 +112,7 @@ obj-$(CONFIG_LOONGSON_HTPIC) += irq-loongson-htpic.o
obj-$(CONFIG_LOONGSON_HTVEC) += irq-loongson-htvec.o
obj-$(CONFIG_LOONGSON_PCH_PIC) += irq-loongson-pch-pic.o
obj-$(CONFIG_LOONGSON_PCH_MSI) += irq-loongson-pch-msi.o
+obj-$(CONFIG_LOONGSON_PCH_LPC) += irq-loongson-pch-lpc.o
obj-$(CONFIG_MST_IRQ) += irq-mst-intc.o
obj-$(CONFIG_SL28CPLD_INTC) += irq-sl28cpld.o
obj-$(CONFIG_MACH_REALTEK_RTL) += irq-realtek-rtl.o
diff --git a/drivers/irqchip/irq-loongson-pch-lpc.c b/drivers/irqchip/irq-loongson-pch-lpc.c
new file mode 100644
index 000000000000..a2236089ee4d
--- /dev/null
+++ b/drivers/irqchip/irq-loongson-pch-lpc.c
@@ -0,0 +1,204 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Loongson LPC Interrupt Controller support
+ *
+ * Copyright (C) 2020-2021 Loongson Technology Corporation Limited
+ */
+
+#define pr_fmt(fmt) "lpc: " fmt
+
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/irqchip.h>
+#include <linux/irqchip/chained_irq.h>
+#include <linux/irqdomain.h>
+#include <linux/kernel.h>
+#include <linux/syscore_ops.h>
+
+/* Registers */
+#define LPC_INT_CTL 0x00
+#define LPC_INT_ENA 0x04
+#define LPC_INT_STS 0x08
+#define LPC_INT_CLR 0x0c
+#define LPC_INT_POL 0x10
+#define LPC_COUNT 16
+
+struct pch_lpc {
+ void __iomem *base;
+ struct irq_domain *lpc_domain;
+ struct fwnode_handle *domain_handle;
+ raw_spinlock_t lpc_lock;
+ u32 saved_reg_ctl;
+ u32 saved_reg_ena;
+ u32 saved_reg_pol;
+};
+
+static struct pch_lpc *pch_lpc_priv;
+
+static void ack_lpc_irq(struct irq_data *d)
+{
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&pch_lpc_priv->lpc_lock, flags);
+ writel(0x1 << d->irq, pch_lpc_priv->base + LPC_INT_CLR);
+ raw_spin_unlock_irqrestore(&pch_lpc_priv->lpc_lock, flags);
+}
+static void mask_lpc_irq(struct irq_data *d)
+{
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&pch_lpc_priv->lpc_lock, flags);
+ writel(readl(pch_lpc_priv->base + LPC_INT_ENA) & (~(0x1 << (d->irq))),
+ pch_lpc_priv->base + LPC_INT_ENA);
+ raw_spin_unlock_irqrestore(&pch_lpc_priv->lpc_lock, flags);
+}
+
+static void mask_ack_lpc_irq(struct irq_data *d)
+{
+}
+
+static void unmask_lpc_irq(struct irq_data *d)
+{
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&pch_lpc_priv->lpc_lock, flags);
+ writel(readl(pch_lpc_priv->base + LPC_INT_ENA) | (0x1 << (d->irq)),
+ pch_lpc_priv->base + LPC_INT_ENA);
+ raw_spin_unlock_irqrestore(&pch_lpc_priv->lpc_lock, flags);
+}
+
+static struct irq_chip pch_lpc_irq_chip = {
+ .name = "PCH LPC",
+ .irq_mask = mask_lpc_irq,
+ .irq_unmask = unmask_lpc_irq,
+ .irq_ack = ack_lpc_irq,
+ .irq_mask_ack = mask_ack_lpc_irq,
+ .irq_eoi = unmask_lpc_irq,
+ .flags = IRQCHIP_SKIP_SET_WAKE,
+};
+
+static void lpc_irq_dispatch(struct irq_desc *desc)
+{
+ struct irq_chip *chip = irq_desc_get_chip(desc);
+ u32 pending;
+
+ chained_irq_enter(chip, desc);
+
+ pending = readl(pch_lpc_priv->base + LPC_INT_ENA);
+ pending &= readl(pch_lpc_priv->base + LPC_INT_STS);
+ if (!pending)
+ spurious_interrupt();
+
+ while (pending) {
+ int bit = __ffs(pending);
+
+ generic_handle_irq(bit);
+ pending &= ~BIT(bit);
+ }
+ chained_irq_exit(chip, desc);
+}
+
+static int pch_lpc_map(struct irq_domain *d, unsigned int irq,
+ irq_hw_number_t hw)
+{
+ irq_set_chip_and_handler(irq, &pch_lpc_irq_chip, handle_level_irq);
+ return 0;
+}
+
+static const struct irq_domain_ops pch_lpc_domain_ops = {
+ .map = pch_lpc_map,
+ .xlate = irq_domain_xlate_onecell,
+};
+
+static void pch_lpc_reset(struct pch_lpc *priv)
+{
+ /* Enable the LPC interrupt, bit31: en bit30: edge */
+ writel(0x80000000, priv->base + LPC_INT_CTL);
+ writel(0, priv->base + LPC_INT_ENA);
+ /* Clear all 18-bit interrpt bit */
+ writel(0x3ffff, priv->base + LPC_INT_CLR);
+}
+
+static int pch_lpc_disabled(struct pch_lpc *priv)
+{
+ return (readl(priv->base + LPC_INT_ENA) == 0xffffffff) &&
+ (readl(priv->base + LPC_INT_STS) == 0xffffffff);
+}
+
+static int pch_lpc_suspend(void)
+{
+ pch_lpc_priv->saved_reg_ctl = readl(pch_lpc_priv->base + LPC_INT_CTL);
+ pch_lpc_priv->saved_reg_ena = readl(pch_lpc_priv->base + LPC_INT_ENA);
+ pch_lpc_priv->saved_reg_pol = readl(pch_lpc_priv->base + LPC_INT_POL);
+ return 0;
+}
+
+static void pch_lpc_resume(void)
+{
+ writel(pch_lpc_priv->saved_reg_ctl, pch_lpc_priv->base + LPC_INT_CTL);
+ writel(pch_lpc_priv->saved_reg_ena, pch_lpc_priv->base + LPC_INT_ENA);
+ writel(pch_lpc_priv->saved_reg_pol, pch_lpc_priv->base + LPC_INT_POL);
+}
+
+static struct syscore_ops pch_lpc_syscore_ops = {
+ .suspend = pch_lpc_suspend,
+ .resume = pch_lpc_resume,
+};
+
+struct irq_domain *pch_lpc_acpi_init(struct irq_domain *parent,
+ struct acpi_madt_lpc_pic *acpi_pchlpc)
+{
+ int parent_irq;
+ struct pch_lpc *priv;
+ struct irq_fwspec fwspec;
+
+ if (!acpi_pchlpc)
+ return NULL;
+
+ priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return NULL;
+
+ raw_spin_lock_init(&priv->lpc_lock);
+
+ priv->base = ioremap(acpi_pchlpc->address, acpi_pchlpc->size);
+ if (!priv->base)
+ goto free_priv;
+
+ if (pch_lpc_disabled(priv)) {
+ pr_err("Failed to get LPC status\n");
+ goto iounmap_base;
+ }
+
+ priv->domain_handle = irq_domain_alloc_fwnode((phys_addr_t *)acpi_pchlpc);
+ if (!priv->domain_handle) {
+ pr_err("Unable to allocate domain handle\n");
+ goto iounmap_base;
+ }
+ priv->lpc_domain = irq_domain_add_legacy(NULL, LPC_COUNT, 0, 0,
+ &pch_lpc_domain_ops, priv);
+ if (!priv->lpc_domain) {
+ pr_err("Failed to create IRQ domain\n");
+ goto iounmap_base;
+ }
+ pch_lpc_reset(priv);
+
+ fwspec.fwnode = parent->fwnode;
+ fwspec.param[0] = acpi_pchlpc->cascade;
+ fwspec.param[1] = IRQ_TYPE_LEVEL_HIGH;
+ fwspec.param_count = 2;
+ parent_irq = irq_create_fwspec_mapping(&fwspec);
+ irq_set_chained_handler_and_data(parent_irq, lpc_irq_dispatch, priv);
+ pch_lpc_priv = priv;
+
+ register_syscore_ops(&pch_lpc_syscore_ops);
+
+ return irq_find_matching_fwnode(priv->domain_handle, DOMAIN_BUS_ANY);
+
+iounmap_base:
+ iounmap(priv->base);
+free_priv:
+ kfree(priv);
+
+ return NULL;
+}
--
2.27.0


2021-12-16 15:06:25

by Marc Zyngier

[permalink] [raw]
Subject: Re: [PATCH V8 02/10] irqchip/loongson-pch-pic: Add ACPI init support

On Thu, 16 Dec 2021 12:53:48 +0000,
Huacai Chen <[email protected]> wrote:
>
> 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 <[email protected]>
> ---
> drivers/irqchip/irq-loongson-pch-pic.c | 108 ++++++++++++++++++-------
> 1 file changed, 81 insertions(+), 27 deletions(-)

[...]

>
> +#ifdef CONFIG_ACPI
> +
> +struct irq_domain *pch_pic_acpi_init(struct irq_domain *parent,
> + struct acpi_madt_bio_pic *acpi_pchpic)

Who is calling this? This works the opposite way from what the arm64
irqchips are doing. Why? I have the ugly feeling that this is called
from the arch code, bypassing the existing infrastructure...

M.

--
Without deviation from the norm, progress is not possible.

2021-12-17 04:48:07

by Huacai Chen

[permalink] [raw]
Subject: Re: [PATCH V8 02/10] irqchip/loongson-pch-pic: Add ACPI init support

Hi, Marc,

On Thu, Dec 16, 2021 at 11:06 PM Marc Zyngier <[email protected]> wrote:
>
> On Thu, 16 Dec 2021 12:53:48 +0000,
> Huacai Chen <[email protected]> wrote:
> >
> > 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 <[email protected]>
> > ---
> > drivers/irqchip/irq-loongson-pch-pic.c | 108 ++++++++++++++++++-------
> > 1 file changed, 81 insertions(+), 27 deletions(-)
>
> [...]
>
> >
> > +#ifdef CONFIG_ACPI
> > +
> > +struct irq_domain *pch_pic_acpi_init(struct irq_domain *parent,
> > + struct acpi_madt_bio_pic *acpi_pchpic)
>
> Who is calling this? This works the opposite way from what the arm64
> irqchips are doing. Why? I have the ugly feeling that this is called
> from the arch code, bypassing the existing infrastructure...
Yes, this is called from the arch code and a bit ugly, but I can't
find a better way to do this.

Is the "existing infrastructure" declare the irqchip init function
with IRQCHIP_ACPI_DECLARE and the arch code only need to call
irqchip_init()? Then we have a problem: our irqchips have a 4 level
hierachy and the parent should be initialized before its children. In
FDT world this is not a problem, because of_irq_init() will sort
irqchip drivers to ensure the right order. But in ACPI world,
acpi_probe_device_table just call init functions in the linking order.
If we want to control the order, it seems we can only sort the drivers
in drivers/irq/Makefile. But I don't think this is a good idea...

If there are better solutions, please let me know. Thanks.

Huacai
>
> M.
>
> --
> Without deviation from the norm, progress is not possible.

2021-12-20 12:13:28

by Marc Zyngier

[permalink] [raw]
Subject: Re: [PATCH V8 02/10] irqchip/loongson-pch-pic: Add ACPI init support

On Fri, 17 Dec 2021 04:45:24 +0000,
Huacai Chen <[email protected]> wrote:
>
> Hi, Marc,
>
> On Thu, Dec 16, 2021 at 11:06 PM Marc Zyngier <[email protected]> wrote:
> >
> > On Thu, 16 Dec 2021 12:53:48 +0000,
> > Huacai Chen <[email protected]> wrote:
> > >
> > > 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 <[email protected]>
> > > ---
> > > drivers/irqchip/irq-loongson-pch-pic.c | 108 ++++++++++++++++++-------
> > > 1 file changed, 81 insertions(+), 27 deletions(-)
> >
> > [...]
> >
> > >
> > > +#ifdef CONFIG_ACPI
> > > +
> > > +struct irq_domain *pch_pic_acpi_init(struct irq_domain *parent,
> > > + struct acpi_madt_bio_pic *acpi_pchpic)
> >
> > Who is calling this? This works the opposite way from what the arm64
> > irqchips are doing. Why? I have the ugly feeling that this is called
> > from the arch code, bypassing the existing infrastructure...
> Yes, this is called from the arch code and a bit ugly, but I can't
> find a better way to do this.
>
> Is the "existing infrastructure" declare the irqchip init function
> with IRQCHIP_ACPI_DECLARE and the arch code only need to call
> irqchip_init()? Then we have a problem: our irqchips have a 4 level
> hierachy and the parent should be initialized before its children. In
> FDT world this is not a problem, because of_irq_init() will sort
> irqchip drivers to ensure the right order. But in ACPI world,
> acpi_probe_device_table just call init functions in the linking order.
> If we want to control the order, it seems we can only sort the drivers
> in drivers/irq/Makefile. But I don't think this is a good idea...
>
> If there are better solutions, please let me know. Thanks.

We have the exact same thing on the arm64 side, and we don't need of
this to be arch specific:

- The MADT table describes the root interrupt controller, and it is
probed via IRQCHIP_ACPI_DECLARE().

- Each children controller is declared in ACPI as a *device*, and is
both an interrupt producer and an interrupt consumer. Normal probe
deferral rules apply. See irq-mbigen.c for an example of how this is
done.

With that, you can remove all the probing order management from your
arch code and let the standard Linux driver model take over.

M.

--
Without deviation from the norm, progress is not possible.

2021-12-24 07:32:06

by Huacai Chen

[permalink] [raw]
Subject: Re: [PATCH V8 02/10] irqchip/loongson-pch-pic: Add ACPI init support

Hi, Marc,

On Mon, Dec 20, 2021 at 8:13 PM Marc Zyngier <[email protected]> wrote:
>
> On Fri, 17 Dec 2021 04:45:24 +0000,
> Huacai Chen <[email protected]> wrote:
> >
> > Hi, Marc,
> >
> > On Thu, Dec 16, 2021 at 11:06 PM Marc Zyngier <[email protected]> wrote:
> > >
> > > On Thu, 16 Dec 2021 12:53:48 +0000,
> > > Huacai Chen <[email protected]> wrote:
> > > >
> > > > 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 <[email protected]>
> > > > ---
> > > > drivers/irqchip/irq-loongson-pch-pic.c | 108 ++++++++++++++++++-------
> > > > 1 file changed, 81 insertions(+), 27 deletions(-)
> > >
> > > [...]
> > >
> > > >
> > > > +#ifdef CONFIG_ACPI
> > > > +
> > > > +struct irq_domain *pch_pic_acpi_init(struct irq_domain *parent,
> > > > + struct acpi_madt_bio_pic *acpi_pchpic)
> > >
> > > Who is calling this? This works the opposite way from what the arm64
> > > irqchips are doing. Why? I have the ugly feeling that this is called
> > > from the arch code, bypassing the existing infrastructure...
> > Yes, this is called from the arch code and a bit ugly, but I can't
> > find a better way to do this.
> >
> > Is the "existing infrastructure" declare the irqchip init function
> > with IRQCHIP_ACPI_DECLARE and the arch code only need to call
> > irqchip_init()? Then we have a problem: our irqchips have a 4 level
> > hierachy and the parent should be initialized before its children. In
> > FDT world this is not a problem, because of_irq_init() will sort
> > irqchip drivers to ensure the right order. But in ACPI world,
> > acpi_probe_device_table just call init functions in the linking order.
> > If we want to control the order, it seems we can only sort the drivers
> > in drivers/irq/Makefile. But I don't think this is a good idea...
> >
> > If there are better solutions, please let me know. Thanks.
>
> We have the exact same thing on the arm64 side, and we don't need of
> this to be arch specific:
>
> - The MADT table describes the root interrupt controller, and it is
> probed via IRQCHIP_ACPI_DECLARE().
>
> - Each children controller is declared in ACPI as a *device*, and is
> both an interrupt producer and an interrupt consumer. Normal probe
> deferral rules apply. See irq-mbigen.c for an example of how this is
> done.
Thank you for your suggestions, I have tried but failed. It seems
there are some differences between irq-mbigen.c and our irqchips.
Because our irqchips are mandatory while mbigen is optional. If we
declare our irqchips as devices, they are initialized in the initcall
phase, which is too late for pci devices.

Huacai

>
> With that, you can remove all the probing order management from your
> arch code and let the standard Linux driver model take over.
>
> M.
>
> --
> Without deviation from the norm, progress is not possible.

2021-12-24 09:51:50

by Marc Zyngier

[permalink] [raw]
Subject: Re: [PATCH V8 02/10] irqchip/loongson-pch-pic: Add ACPI init support

On Fri, 24 Dec 2021 07:31:53 +0000,
Huacai Chen <[email protected]> wrote:
>
> Hi, Marc,
>
> On Mon, Dec 20, 2021 at 8:13 PM Marc Zyngier <[email protected]> wrote:
> >
> > On Fri, 17 Dec 2021 04:45:24 +0000,
> > Huacai Chen <[email protected]> wrote:
> > >
> > > Hi, Marc,
> > >
> > > On Thu, Dec 16, 2021 at 11:06 PM Marc Zyngier <[email protected]> wrote:
> > > >
> > > > On Thu, 16 Dec 2021 12:53:48 +0000,
> > > > Huacai Chen <[email protected]> wrote:
> > > > >
> > > > > 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 <[email protected]>
> > > > > ---
> > > > > drivers/irqchip/irq-loongson-pch-pic.c | 108 ++++++++++++++++++-------
> > > > > 1 file changed, 81 insertions(+), 27 deletions(-)
> > > >
> > > > [...]
> > > >
> > > > >
> > > > > +#ifdef CONFIG_ACPI
> > > > > +
> > > > > +struct irq_domain *pch_pic_acpi_init(struct irq_domain *parent,
> > > > > + struct acpi_madt_bio_pic *acpi_pchpic)
> > > >
> > > > Who is calling this? This works the opposite way from what the arm64
> > > > irqchips are doing. Why? I have the ugly feeling that this is called
> > > > from the arch code, bypassing the existing infrastructure...
> > > Yes, this is called from the arch code and a bit ugly, but I can't
> > > find a better way to do this.
> > >
> > > Is the "existing infrastructure" declare the irqchip init function
> > > with IRQCHIP_ACPI_DECLARE and the arch code only need to call
> > > irqchip_init()? Then we have a problem: our irqchips have a 4 level
> > > hierachy and the parent should be initialized before its children. In
> > > FDT world this is not a problem, because of_irq_init() will sort
> > > irqchip drivers to ensure the right order. But in ACPI world,
> > > acpi_probe_device_table just call init functions in the linking order.
> > > If we want to control the order, it seems we can only sort the drivers
> > > in drivers/irq/Makefile. But I don't think this is a good idea...
> > >
> > > If there are better solutions, please let me know. Thanks.
> >
> > We have the exact same thing on the arm64 side, and we don't need of
> > this to be arch specific:
> >
> > - The MADT table describes the root interrupt controller, and it is
> > probed via IRQCHIP_ACPI_DECLARE().
> >
> > - Each children controller is declared in ACPI as a *device*, and is
> > both an interrupt producer and an interrupt consumer. Normal probe
> > deferral rules apply. See irq-mbigen.c for an example of how this is
> > done.
> Thank you for your suggestions, I have tried but failed. It seems
> there are some differences between irq-mbigen.c and our irqchips.
> Because our irqchips are mandatory while mbigen is optional.

The fact that this is optional has nothing to do with it. On a system
that requires mbigen to boot (both mass storage and networking are
hanging off it), there is a guarantee that the probe order will
respect the resource dependency.

And if that's not enough, -EPROBE_DEFER is your friend, always.

> If we declare our irqchips as devices, they are initialized in the
> initcall phase, which is too late for pci devices.

This suggests that your PCIe driver is either not enforcing the
dependencies on the interrupt controller (bad), or that the core code
is not made aware of the dependencies (equally bad).

In any case, this needs sorting, because a new architecture should be
able to boot without resorting to handcrafted dependencies that will
inevitably result in a larger pile of hacks over time. It is much
easier to solve it before day-1.

M.

--
Without deviation from the norm, progress is not possible.

2022-01-25 08:58:44

by Huacai Chen

[permalink] [raw]
Subject: Re: [PATCH V8 02/10] irqchip/loongson-pch-pic: Add ACPI init support

Hi, Marc,

On Fri, Dec 24, 2021 at 5:51 PM Marc Zyngier <[email protected]> wrote:
>
> On Fri, 24 Dec 2021 07:31:53 +0000,
> Huacai Chen <[email protected]> wrote:
> >
> > Hi, Marc,
> >
> > On Mon, Dec 20, 2021 at 8:13 PM Marc Zyngier <[email protected]> wrote:
> > >
> > > On Fri, 17 Dec 2021 04:45:24 +0000,
> > > Huacai Chen <[email protected]> wrote:
> > > >
> > > > Hi, Marc,
> > > >
> > > > On Thu, Dec 16, 2021 at 11:06 PM Marc Zyngier <[email protected]> wrote:
> > > > >
> > > > > On Thu, 16 Dec 2021 12:53:48 +0000,
> > > > > Huacai Chen <[email protected]> wrote:
> > > > > >
> > > > > > 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 <[email protected]>
> > > > > > ---
> > > > > > drivers/irqchip/irq-loongson-pch-pic.c | 108 ++++++++++++++++++-------
> > > > > > 1 file changed, 81 insertions(+), 27 deletions(-)
> > > > >
> > > > > [...]
> > > > >
> > > > > >
> > > > > > +#ifdef CONFIG_ACPI
> > > > > > +
> > > > > > +struct irq_domain *pch_pic_acpi_init(struct irq_domain *parent,
> > > > > > + struct acpi_madt_bio_pic *acpi_pchpic)
> > > > >
> > > > > Who is calling this? This works the opposite way from what the arm64
> > > > > irqchips are doing. Why? I have the ugly feeling that this is called
> > > > > from the arch code, bypassing the existing infrastructure...
> > > > Yes, this is called from the arch code and a bit ugly, but I can't
> > > > find a better way to do this.
> > > >
> > > > Is the "existing infrastructure" declare the irqchip init function
> > > > with IRQCHIP_ACPI_DECLARE and the arch code only need to call
> > > > irqchip_init()? Then we have a problem: our irqchips have a 4 level
> > > > hierachy and the parent should be initialized before its children. In
> > > > FDT world this is not a problem, because of_irq_init() will sort
> > > > irqchip drivers to ensure the right order. But in ACPI world,
> > > > acpi_probe_device_table just call init functions in the linking order.
> > > > If we want to control the order, it seems we can only sort the drivers
> > > > in drivers/irq/Makefile. But I don't think this is a good idea...
> > > >
> > > > If there are better solutions, please let me know. Thanks.
> > >
> > > We have the exact same thing on the arm64 side, and we don't need of
> > > this to be arch specific:
> > >
> > > - The MADT table describes the root interrupt controller, and it is
> > > probed via IRQCHIP_ACPI_DECLARE().
> > >
> > > - Each children controller is declared in ACPI as a *device*, and is
> > > both an interrupt producer and an interrupt consumer. Normal probe
> > > deferral rules apply. See irq-mbigen.c for an example of how this is
> > > done.
> > Thank you for your suggestions, I have tried but failed. It seems
> > there are some differences between irq-mbigen.c and our irqchips.
> > Because our irqchips are mandatory while mbigen is optional.
>
> The fact that this is optional has nothing to do with it. On a system
> that requires mbigen to boot (both mass storage and networking are
> hanging off it), there is a guarantee that the probe order will
> respect the resource dependency.
>
> And if that's not enough, -EPROBE_DEFER is your friend, always.
>
> > If we declare our irqchips as devices, they are initialized in the
> > initcall phase, which is too late for pci devices.
>
> This suggests that your PCIe driver is either not enforcing the
> dependencies on the interrupt controller (bad), or that the core code
> is not made aware of the dependencies (equally bad).
>
> In any case, this needs sorting, because a new architecture should be
> able to boot without resorting to handcrafted dependencies that will
> inevitably result in a larger pile of hacks over time. It is much
> easier to solve it before day-1.

Sorry for the long delay, but we still failed.

- There are several kinds of irq chips(e.g. pchpic、eiointc、cpuintc)
for LoongArch. SCI interrupt (Fixed hardware is implemented for
LoongArch in pch such as LS7A1000, and SCI interrupt is used for fixed
event handling.) is an irq input of pch irq chip which routes
interrupts to cpu as following irq chips path:

sci interrupt->|pchpic| ->|eiointc|->|cpuintc|

sci_interrupt will be transferred from gsi to irq through
acpi_gsi_to_irq in acpi_enable_subsystem called from acpi_bus_init
before acpi_scan_init where acpi device namespace is created, so we
should build pch irq domain and related upstream irq domains before
acpi_bus_init.

- PCI bus enumeration is executed from acpi_scan_init, and
pci_set_msi_domain will be called for setting msi_domain of enumerated
pci device. In pci_set_msi_domain, msi domain may be got through
pcibios_device_add, fdt, iort(used for arm64) or inheriting from host
bridge domain. And in each way, the msi domain needs to be found by
calling irq_find_matching_fwnode(fwnode, DOMAIN_BUS_PCI_MSI) to match
one from the registered msi domain before. So we build the msi domain
as x86 and arm64 before acpi_scan_init. The msi domain is hierarchic
as following:

msi interrupt->|msipic| ->|eiointc|->|cpuintc|

- Yes, a driver can be deferred probed when get -EPROBE_DEFER on
probing, but both sci interrupt transfer and pci bus enumeration are
common code (not private driver for LoongArch).

So, declaring pic devices in DSDT for seems not suitable, we can only
select the X86-like way which is a bit ugly.

Huacai

>
> M.
>
> --
> Without deviation from the norm, progress is not possible.