[PATCH V12 0/3] irqchip: qcom: Add IRQ combiner driver

[PATCH V12 0/3] irqchip: qcom: Add IRQ combiner driver

[Agustin Vega-Frias]

Add support for IRQ combiners in the Top-level Control and Status
Registers (TCSR) hardware block in Qualcomm Technologies chips.

The first patch prevents the ACPI core from attempting to map IRQ resources
with a valid ResourceSource as GSIs.

The second patch adds support for ResourceSource/IRQ domain mapping and
fixes IRQ probe deferral by allowing platform_device IRQ resources to be
re-initialized from the corresponding ACPI IRQ resource.

Both changes described above are conditional on the ACPI_GENERIC_GSI config.

The third patch takes advantage of the new capabilities to implement
the driver for the IRQ combiners.

Tested on top of v4.10-rc6.

Changes V11 -> V12:
* Remove probe table, add that optimization later.
* Fix some minor style issues.

Changes V10 -> V11:
* Add probe table and use it to implement driver presence detection.
* Fix kernel doc formatting in drivers/acpi/irq.c and some minor style issues.
* Minor bug fixes in the driver.

Changes V9 -> V10:
* Add checks for the producer_consumer field to not use produced IRQ
  resources as consumed.
* Minor bug fixes in the driver.

Changes V8 -> V9:
* Do not attempt the mapping for non-GSI IRQs during bus scan.
* Make some public APIs private to drivers/acpi/irq.c since they are no
  longer used on other modules.

Agustin Vega-Frias (3):
  ACPI: Generic GSI: Do not attempt to map non-GSI IRQs during bus scan
  ACPI: Add support for ResourceSource/IRQ domain mapping
  irqchip: qcom: Add IRQ combiner driver

 drivers/acpi/Makefile               |   2 +-
 drivers/acpi/{gsi.c => irq.c}       | 199 ++++++++++++++++++++++++
 drivers/acpi/resource.c             |  18 ++-
 drivers/base/platform.c             |  10 ++
 drivers/irqchip/Kconfig             |   9 ++
 drivers/irqchip/Makefile            |   1 +
 drivers/irqchip/qcom-irq-combiner.c | 296 ++++++++++++++++++++++++++++++++++++
 include/linux/acpi.h                |  10 ++
 8 files changed, 543 insertions(+), 2 deletions(-)
 rename drivers/acpi/{gsi.c => irq.c} (31%)
 create mode 100644 drivers/irqchip/qcom-irq-combiner.c

--
Qualcomm Datacenter Technologies, Inc. on behalf of the Qualcomm Technologies, Inc.
Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.

[PATCH V12 1/3] ACPI: Generic GSI: Do not attempt to map non-GSI IRQs during bus scan

[Agustin Vega-Frias]

ACPI extended IRQ resources may contain a Resource Source field to specify
an alternate interrupt controller, attempting to map them as GSIs is
incorrect, so just disable the platform resource.

Since this field is currently ignored, we make this change conditional
on CONFIG_ACPI_GENERIC_GSI to keep the current behavior on x86 platforms,
in case some existing ACPI tables are using this incorrectly.

Acked-by: Rafael J. Wysocki <rafael@kernel.org>
Signed-off-by: Agustin Vega-Frias <agustinv@codeaurora.org>
---
 drivers/acpi/resource.c | 18 +++++++++++++++++-
 1 file changed, 17 insertions(+), 1 deletion(-)

diff --git a/drivers/acpi/resource.c b/drivers/acpi/resource.c
index cb57962..8b11d6d 100644
--- a/drivers/acpi/resource.c
+++ b/drivers/acpi/resource.c
@@ -43,6 +43,19 @@ static inline bool acpi_iospace_resource_valid(struct resource *res)
 acpi_iospace_resource_valid(struct resource *res) { return true; }
 #endif
 
+#if IS_ENABLED(CONFIG_ACPI_GENERIC_GSI)
+static inline bool is_gsi(struct acpi_resource_extended_irq *ext_irq)
+{
+	return ext_irq->resource_source.string_length == 0 &&
+	       ext_irq->producer_consumer == ACPI_CONSUMER;
+}
+#else
+static inline bool is_gsi(struct acpi_resource_extended_irq *ext_irq)
+{
+	return true;
+}
+#endif
+
 static bool acpi_dev_resource_len_valid(u64 start, u64 end, u64 len, bool io)
 {
 	u64 reslen = end - start + 1;
@@ -470,9 +483,12 @@ bool acpi_dev_resource_interrupt(struct acpi_resource *ares, int index,
 			acpi_dev_irqresource_disabled(res, 0);
 			return false;
 		}
-		acpi_dev_get_irqresource(res, ext_irq->interrupts[index],
+		if (is_gsi(ext_irq))
+			acpi_dev_get_irqresource(res, ext_irq->interrupts[index],
 					 ext_irq->triggering, ext_irq->polarity,
 					 ext_irq->sharable, false);
+		else
+			acpi_dev_irqresource_disabled(res, 0);
 		break;
 	default:
 		res->flags = 0;
-- 
Qualcomm Datacenter Technologies, Inc. on behalf of the Qualcomm Technologies, Inc.
Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.

[PATCH V12 2/3] ACPI: Add support for ResourceSource/IRQ domain mapping

[Agustin Vega-Frias]

ACPI extended IRQ resources may contain a ResourceSource to specify
an alternate interrupt controller. Introduce acpi_irq_get and use it
to implement ResourceSource/IRQ domain mapping.

The new API is similar to of_irq_get and allows re-initialization
of a platform resource from the ACPI extended IRQ resource, and
provides proper behavior for probe deferral when the domain is not
yet present when called.

Acked-by: Rafael J. Wysocki <rafael@kernel.org>
Signed-off-by: Agustin Vega-Frias <agustinv@codeaurora.org>
---
 drivers/acpi/Makefile         |   2 +-
 drivers/acpi/{gsi.c => irq.c} | 199 ++++++++++++++++++++++++++++++++++++++++++
 drivers/base/platform.c       |  10 +++
 include/linux/acpi.h          |  10 +++
 4 files changed, 220 insertions(+), 1 deletion(-)
 rename drivers/acpi/{gsi.c => irq.c} (31%)

diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile
index 9ed0878..a391bbc 100644
--- a/drivers/acpi/Makefile
+++ b/drivers/acpi/Makefile
@@ -55,7 +55,7 @@ acpi-$(CONFIG_DEBUG_FS)		+= debugfs.o
 acpi-$(CONFIG_ACPI_NUMA)	+= numa.o
 acpi-$(CONFIG_ACPI_PROCFS_POWER) += cm_sbs.o
 acpi-y				+= acpi_lpat.o
-acpi-$(CONFIG_ACPI_GENERIC_GSI) += gsi.o
+acpi-$(CONFIG_ACPI_GENERIC_GSI) += irq.o
 acpi-$(CONFIG_ACPI_WATCHDOG)	+= acpi_watchdog.o
 
 # These are (potentially) separate modules
diff --git a/drivers/acpi/gsi.c b/drivers/acpi/irq.c
similarity index 31%
rename from drivers/acpi/gsi.c
rename to drivers/acpi/irq.c
index ee9e0f2..830299a 100644
--- a/drivers/acpi/gsi.c
+++ b/drivers/acpi/irq.c
@@ -85,6 +85,205 @@ void acpi_unregister_gsi(u32 gsi)
 EXPORT_SYMBOL_GPL(acpi_unregister_gsi);
 
 /**
+ * acpi_get_irq_source_fwhandle() - Retrieve fwhandle from IRQ resource source.
+ * @source: acpi_resource_source to use for the lookup.
+ *
+ * Description:
+ * Retrieve the fwhandle of the device referenced by the given IRQ resource
+ * source.
+ *
+ * Return:
+ * The referenced device fwhandle or NULL on failure
+ */
+static struct fwnode_handle *
+acpi_get_irq_source_fwhandle(const struct acpi_resource_source *source)
+{
+	struct fwnode_handle *result;
+	struct acpi_device *device;
+	acpi_handle handle;
+	acpi_status status;
+
+	if (!source->string_length)
+		return acpi_gsi_domain_id;
+
+	status = acpi_get_handle(NULL, source->string_ptr, &handle);
+	if (WARN_ON(ACPI_FAILURE(status)))
+		return NULL;
+
+	device = acpi_bus_get_acpi_device(handle);
+	if (WARN_ON(!device))
+		return NULL;
+
+	result = &device->fwnode;
+	acpi_bus_put_acpi_device(device);
+	return result;
+}
+
+/*
+ * Context for the resource walk used to lookup IRQ resources.
+ * Contains a return code, the lookup index, and references to the flags
+ * and fwspec where the result is returned.
+ */
+struct acpi_irq_parse_one_ctx {
+	int rc;
+	unsigned int index;
+	unsigned long *res_flags;
+	struct irq_fwspec *fwspec;
+};
+
+/**
+ * acpi_irq_parse_one_match - Handle a matching IRQ resource.
+ * @fwnode: matching fwnode
+ * @hwirq: hardware IRQ number
+ * @triggering: triggering attributes of hwirq
+ * @polarity: polarity attributes of hwirq
+ * @polarity: polarity attributes of hwirq
+ * @shareable: shareable attributes of hwirq
+ * @ctx: acpi_irq_parse_one_ctx updated by this function
+ *
+ * Description:
+ * Handle a matching IRQ resource by populating the given ctx with
+ * the information passed.
+ */
+static inline void acpi_irq_parse_one_match(struct fwnode_handle *fwnode,
+					    u32 hwirq, u8 triggering,
+					    u8 polarity, u8 shareable,
+					    struct acpi_irq_parse_one_ctx *ctx)
+{
+	if (!fwnode)
+		return;
+	ctx->rc = 0;
+	*ctx->res_flags = acpi_dev_irq_flags(triggering, polarity, shareable);
+	ctx->fwspec->fwnode = fwnode;
+	ctx->fwspec->param[0] = hwirq;
+	ctx->fwspec->param[1] = acpi_dev_get_irq_type(triggering, polarity);
+	ctx->fwspec->param_count = 2;
+}
+
+/**
+ * acpi_irq_parse_one_cb - Handle the given resource.
+ * @ares: resource to handle
+ * @context: context for the walk
+ *
+ * Description:
+ * This is called by acpi_walk_resources passing each resource returned by
+ * the _CRS method. We only inspect IRQ resources. Since IRQ resources
+ * might contain multiple interrupts we check if the index is within this
+ * one's interrupt array, otherwise we subtract the current resource IRQ
+ * count from the lookup index to prepare for the next resource.
+ * Once a match is found we call acpi_irq_parse_one_match to populate
+ * the result and end the walk by returning AE_CTRL_TERMINATE.
+ *
+ * Return:
+ * AE_OK if the walk should continue, AE_CTRL_TERMINATE if a matching
+ * IRQ resource was found.
+ */
+static acpi_status acpi_irq_parse_one_cb(struct acpi_resource *ares,
+					 void *context)
+{
+	struct acpi_irq_parse_one_ctx *ctx = context;
+	struct acpi_resource_irq *irq;
+	struct acpi_resource_extended_irq *eirq;
+	struct fwnode_handle *fwnode;
+
+	switch (ares->type) {
+	case ACPI_RESOURCE_TYPE_IRQ:
+		irq = &ares->data.irq;
+		if (ctx->index >= irq->interrupt_count) {
+			ctx->index -= irq->interrupt_count;
+			return AE_OK;
+		}
+		fwnode = acpi_gsi_domain_id;
+		acpi_irq_parse_one_match(fwnode, irq->interrupts[ctx->index],
+					 irq->triggering, irq->polarity,
+					 irq->sharable, ctx);
+		return AE_CTRL_TERMINATE;
+	case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
+		eirq = &ares->data.extended_irq;
+		if (eirq->producer_consumer == ACPI_PRODUCER)
+			return AE_OK;
+		if (ctx->index >= eirq->interrupt_count) {
+			ctx->index -= eirq->interrupt_count;
+			return AE_OK;
+		}
+		fwnode = acpi_get_irq_source_fwhandle(&eirq->resource_source);
+		acpi_irq_parse_one_match(fwnode, eirq->interrupts[ctx->index],
+					 eirq->triggering, eirq->polarity,
+					 eirq->sharable, ctx);
+		return AE_CTRL_TERMINATE;
+	}
+
+	return AE_OK;
+}
+
+/**
+ * acpi_irq_parse_one - Resolve an interrupt for a device
+ * @handle: the device whose interrupt is to be resolved
+ * @index: index of the interrupt to resolve
+ * @fwspec: structure irq_fwspec filled by this function
+ * @flags: resource flags filled by this function
+ *
+ * Description:
+ * Resolves an interrupt for a device by walking its CRS resources to find
+ * the appropriate ACPI IRQ resource and populating the given struct irq_fwspec
+ * and flags.
+ *
+ * Return:
+ * The result stored in ctx.rc by the callback, or the default -EINVAL value
+ * if an error occurs.
+ */
+static int acpi_irq_parse_one(acpi_handle handle, unsigned int index,
+			      struct irq_fwspec *fwspec, unsigned long *flags)
+{
+	struct acpi_irq_parse_one_ctx ctx = { -EINVAL, index, flags, fwspec };
+
+	acpi_walk_resources(handle, METHOD_NAME__CRS, acpi_irq_parse_one_cb, &ctx);
+	return ctx.rc;
+}
+
+/**
+ * acpi_irq_get - Lookup an ACPI IRQ resource and use it to initialize resource.
+ * @handle: ACPI device handle
+ * @index:  ACPI IRQ resource index to lookup
+ * @res:    Linux IRQ resource to initialize
+ *
+ * Description:
+ * Look for the ACPI IRQ resource with the given index and use it to initialize
+ * the given Linux IRQ resource.
+ *
+ * Return:
+ * 0 on success
+ * -EINVAL if an error occurs
+ * -EPROBE_DEFER if the IRQ lookup/conversion failed
+ */
+int acpi_irq_get(acpi_handle handle, unsigned int index, struct resource *res)
+{
+	struct irq_fwspec fwspec;
+	struct irq_domain *domain;
+	unsigned long flags;
+	int rc;
+
+	rc = acpi_irq_parse_one(handle, index, &fwspec, &flags);
+	if (rc)
+		return rc;
+
+	domain = irq_find_matching_fwnode(fwspec.fwnode, DOMAIN_BUS_ANY);
+	if (!domain)
+		return -EPROBE_DEFER;
+
+	rc = irq_create_fwspec_mapping(&fwspec);
+	if (rc <= 0)
+		return -EINVAL;
+
+	res->start = rc;
+	res->end = rc;
+	res->flags = flags;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(acpi_irq_get);
+
+/**
  * acpi_set_irq_model - Setup the GSI irqdomain information
  * @model: the value assigned to acpi_irq_model
  * @fwnode: the irq_domain identifier for mapping and looking up
diff --git a/drivers/base/platform.c b/drivers/base/platform.c
index c4af003..647e476 100644
--- a/drivers/base/platform.c
+++ b/drivers/base/platform.c
@@ -102,6 +102,16 @@ int platform_get_irq(struct platform_device *dev, unsigned int num)
 	}
 
 	r = platform_get_resource(dev, IORESOURCE_IRQ, num);
+	if (has_acpi_companion(&dev->dev)) {
+		if (r && r->flags & IORESOURCE_DISABLED) {
+			int ret;
+
+			ret = acpi_irq_get(ACPI_HANDLE(&dev->dev), num, r);
+			if (ret)
+				return ret;
+		}
+	}
+
 	/*
 	 * The resources may pass trigger flags to the irqs that need
 	 * to be set up. It so happens that the trigger flags for
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index 5b36974..8e577c2 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -1153,4 +1153,14 @@ static inline void acpi_table_upgrade(void) { }
 static inline int parse_spcr(bool earlycon) { return 0; }
 #endif
 
+#if IS_ENABLED(CONFIG_ACPI_GENERIC_GSI)
+int acpi_irq_get(acpi_handle handle, unsigned int index, struct resource *res);
+#else
+static inline
+int acpi_irq_get(acpi_handle handle, unsigned int index, struct resource *res)
+{
+	return -EINVAL;
+}
+#endif
+
 #endif	/*_LINUX_ACPI_H*/
-- 
Qualcomm Datacenter Technologies, Inc. on behalf of the Qualcomm Technologies, Inc.
Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.

[PATCH V12 3/3] irqchip: qcom: Add IRQ combiner driver

[Agustin Vega-Frias]

Driver for interrupt combiners in the Top-level Control and Status
Registers (TCSR) hardware block in Qualcomm Technologies chips.

An interrupt combiner in this block combines a set of interrupts by
OR'ing the individual interrupt signals into a summary interrupt
signal routed to a parent interrupt controller, and provides read-
only, 32-bit registers to query the status of individual interrupts.
The status bit for IRQ n is bit (n % 32) within register (n / 32)
of the given combiner. Thus, each combiner can be described as a set
of register offsets and the number of IRQs managed.

Signed-off-by: Agustin Vega-Frias <agustinv@codeaurora.org>
---
 drivers/irqchip/Kconfig             |   9 ++
 drivers/irqchip/Makefile            |   1 +
 drivers/irqchip/qcom-irq-combiner.c | 296 ++++++++++++++++++++++++++++++++++++
 3 files changed, 306 insertions(+)
 create mode 100644 drivers/irqchip/qcom-irq-combiner.c

diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index ae96731..125528f 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -283,3 +283,12 @@ config EZNPS_GIC
 config STM32_EXTI
 	bool
 	select IRQ_DOMAIN
+
+config QCOM_IRQ_COMBINER
+	bool "QCOM IRQ combiner support"
+	depends on ARCH_QCOM && ACPI
+	select IRQ_DOMAIN
+	select IRQ_DOMAIN_HIERARCHY
+	help
+	  Say yes here to add support for the IRQ combiner devices embedded
+	  in Qualcomm Technologies chips.
diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
index 0e55d94..5a531863 100644
--- a/drivers/irqchip/Makefile
+++ b/drivers/irqchip/Makefile
@@ -75,3 +75,4 @@ obj-$(CONFIG_LS_SCFG_MSI)		+= irq-ls-scfg-msi.o
 obj-$(CONFIG_EZNPS_GIC)			+= irq-eznps.o
 obj-$(CONFIG_ARCH_ASPEED)		+= irq-aspeed-vic.o
 obj-$(CONFIG_STM32_EXTI) 		+= irq-stm32-exti.o
+obj-$(CONFIG_QCOM_IRQ_COMBINER)		+= qcom-irq-combiner.o
diff --git a/drivers/irqchip/qcom-irq-combiner.c b/drivers/irqchip/qcom-irq-combiner.c
new file mode 100644
index 0000000..03251da
--- /dev/null
+++ b/drivers/irqchip/qcom-irq-combiner.c
@@ -0,0 +1,296 @@
+/* Copyright (c) 2015-2016, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+/*
+ * Driver for interrupt combiners in the Top-level Control and Status
+ * Registers (TCSR) hardware block in Qualcomm Technologies chips.
+ * An interrupt combiner in this block combines a set of interrupts by
+ * OR'ing the individual interrupt signals into a summary interrupt
+ * signal routed to a parent interrupt controller, and provides read-
+ * only, 32-bit registers to query the status of individual interrupts.
+ * The status bit for IRQ n is bit (n % 32) within register (n / 32)
+ * of the given combiner. Thus, each combiner can be described as a set
+ * of register offsets and the number of IRQs managed.
+ */
+
+#define pr_fmt(fmt) "QCOM80B1:" fmt
+
+#include <linux/acpi.h>
+#include <linux/irqchip/chained_irq.h>
+#include <linux/irqdomain.h>
+#include <linux/platform_device.h>
+
+#define REG_SIZE 32
+
+struct combiner_reg {
+	void __iomem *addr;
+	unsigned long enabled;
+};
+
+struct combiner {
+	struct irq_domain   *domain;
+	int                 parent_irq;
+	u32                 nirqs;
+	u32                 nregs;
+	struct combiner_reg regs[0];
+};
+
+static inline int irq_nr(u32 reg, u32 bit)
+{
+	return reg * REG_SIZE + bit;
+}
+
+/*
+ * Handler for the cascaded IRQ.
+ */
+static void combiner_handle_irq(struct irq_desc *desc)
+{
+	struct combiner *combiner = irq_desc_get_handler_data(desc);
+	struct irq_chip *chip = irq_desc_get_chip(desc);
+	u32 reg;
+
+	chained_irq_enter(chip, desc);
+
+	for (reg = 0; reg < combiner->nregs; reg++) {
+		int virq;
+		int hwirq;
+		u32 bit;
+		u32 status;
+
+		bit = readl_relaxed(combiner->regs[reg].addr);
+		status = bit & combiner->regs[reg].enabled;
+		if (!status)
+			pr_warn_ratelimited("Unexpected IRQ on CPU%d: (%08x %08lx %p)\n",
+					    smp_processor_id(), bit,
+					    combiner->regs[reg].enabled,
+					    combiner->regs[reg].addr);
+
+		while (status) {
+			bit = __ffs(status);
+			status &= ~(1 << bit);
+			hwirq = irq_nr(reg, bit);
+			virq = irq_find_mapping(combiner->domain, hwirq);
+			if (virq > 0)
+				generic_handle_irq(virq);
+
+		}
+	}
+
+	chained_irq_exit(chip, desc);
+}
+
+static void combiner_irq_chip_mask_irq(struct irq_data *data)
+{
+	struct combiner *combiner = irq_data_get_irq_chip_data(data);
+	struct combiner_reg *reg = combiner->regs + data->hwirq / REG_SIZE;
+
+	clear_bit(data->hwirq % REG_SIZE, &reg->enabled);
+}
+
+static void combiner_irq_chip_unmask_irq(struct irq_data *data)
+{
+	struct combiner *combiner = irq_data_get_irq_chip_data(data);
+	struct combiner_reg *reg = combiner->regs + data->hwirq / REG_SIZE;
+
+	set_bit(data->hwirq % REG_SIZE, &reg->enabled);
+}
+
+static struct irq_chip irq_chip = {
+	.irq_mask = combiner_irq_chip_mask_irq,
+	.irq_unmask = combiner_irq_chip_unmask_irq,
+	.name = "qcom-irq-combiner"
+};
+
+static int combiner_irq_map(struct irq_domain *domain, unsigned int irq,
+				   irq_hw_number_t hwirq)
+{
+	irq_set_chip_and_handler(irq, &irq_chip, handle_level_irq);
+	irq_set_chip_data(irq, domain->host_data);
+	irq_set_noprobe(irq);
+	return 0;
+}
+
+static void combiner_irq_unmap(struct irq_domain *domain, unsigned int irq)
+{
+	irq_domain_reset_irq_data(irq_get_irq_data(irq));
+}
+
+static int combiner_irq_translate(struct irq_domain *d, struct irq_fwspec *fws,
+				  unsigned long *hwirq, unsigned int *type)
+{
+	struct combiner *combiner = d->host_data;
+
+	if (is_acpi_node(fws->fwnode)) {
+		if (WARN_ON((fws->param_count != 2) ||
+			    (fws->param[0] >= combiner->nirqs) ||
+			    (fws->param[1] & IORESOURCE_IRQ_LOWEDGE) ||
+			    (fws->param[1] & IORESOURCE_IRQ_HIGHEDGE)))
+			return -EINVAL;
+
+		*hwirq = fws->param[0];
+		*type = fws->param[1];
+		return 0;
+	}
+
+	return -EINVAL;
+}
+
+static const struct irq_domain_ops domain_ops = {
+	.map = combiner_irq_map,
+	.unmap = combiner_irq_unmap,
+	.translate = combiner_irq_translate
+};
+
+static acpi_status count_registers_cb(struct acpi_resource *ares, void *context)
+{
+	int *count = context;
+
+	if (ares->type == ACPI_RESOURCE_TYPE_GENERIC_REGISTER)
+		++(*count);
+	return AE_OK;
+}
+
+static int count_registers(struct platform_device *pdev)
+{
+	acpi_handle ahandle = ACPI_HANDLE(&pdev->dev);
+	acpi_status status;
+	int count = 0;
+
+	if (!acpi_has_method(ahandle, METHOD_NAME__CRS))
+		return -EINVAL;
+
+	status = acpi_walk_resources(ahandle, METHOD_NAME__CRS,
+				     count_registers_cb, &count);
+	if (ACPI_FAILURE(status))
+		return -EINVAL;
+	return count;
+}
+
+struct get_registers_context {
+	struct device *dev;
+	struct combiner *combiner;
+	int err;
+};
+
+static acpi_status get_registers_cb(struct acpi_resource *ares, void *context)
+{
+	struct get_registers_context *ctx = context;
+	struct acpi_resource_generic_register *reg;
+	phys_addr_t paddr;
+	void __iomem *vaddr;
+
+	if (ares->type != ACPI_RESOURCE_TYPE_GENERIC_REGISTER)
+		return AE_OK;
+
+	reg = &ares->data.generic_reg;
+	paddr = reg->address;
+	if ((reg->space_id != ACPI_SPACE_MEM) ||
+	    (reg->bit_offset != 0) ||
+	    (reg->bit_width > REG_SIZE)) {
+		dev_err(ctx->dev, "Bad register resource @%pa\n", &paddr);
+		ctx->err = -EINVAL;
+		return AE_ERROR;
+	}
+
+	vaddr = devm_ioremap(ctx->dev, reg->address, REG_SIZE);
+	if (IS_ERR(vaddr)) {
+		dev_err(ctx->dev, "Can't map register @%pa\n", &paddr);
+		ctx->err = PTR_ERR(vaddr);
+		return AE_ERROR;
+	}
+
+	ctx->combiner->regs[ctx->combiner->nregs].addr = vaddr;
+	ctx->combiner->nirqs += reg->bit_width;
+	ctx->combiner->nregs++;
+	return AE_OK;
+}
+
+static int get_registers(struct platform_device *pdev, struct combiner *comb)
+{
+	acpi_handle ahandle = ACPI_HANDLE(&pdev->dev);
+	acpi_status status;
+	struct get_registers_context ctx;
+
+	if (!acpi_has_method(ahandle, METHOD_NAME__CRS))
+		return -EINVAL;
+
+	ctx.dev = &pdev->dev;
+	ctx.combiner = comb;
+	ctx.err = 0;
+
+	status = acpi_walk_resources(ahandle, METHOD_NAME__CRS,
+				     get_registers_cb, &ctx);
+	if (ACPI_FAILURE(status))
+		return ctx.err;
+	return 0;
+}
+
+static int __init combiner_probe(struct platform_device *pdev)
+{
+	struct combiner *combiner;
+	size_t alloc_sz;
+	u32 nregs;
+	int err;
+
+	nregs = count_registers(pdev);
+	if (nregs <= 0) {
+		dev_err(&pdev->dev, "Error reading register resources\n");
+		return -EINVAL;
+	}
+
+	alloc_sz = sizeof(*combiner) + sizeof(struct combiner_reg) * nregs;
+	combiner = devm_kzalloc(&pdev->dev, alloc_sz, GFP_KERNEL);
+	if (!combiner)
+		return -ENOMEM;
+
+	err = get_registers(pdev, combiner);
+	if (err < 0)
+		return err;
+
+	combiner->parent_irq = platform_get_irq(pdev, 0);
+	if (combiner->parent_irq <= 0) {
+		dev_err(&pdev->dev, "Error getting IRQ resource\n");
+		return -EPROBE_DEFER;
+	}
+
+	combiner->domain = irq_domain_create_linear(pdev->dev.fwnode, combiner->nirqs,
+						    &domain_ops, combiner);
+	if (!combiner->domain)
+		/* Errors printed by irq_domain_create_linear */
+		return -ENODEV;
+
+	irq_set_chained_handler_and_data(combiner->parent_irq,
+					 combiner_handle_irq, combiner);
+
+	dev_info(&pdev->dev, "Initialized with [p=%d,n=%d,r=%p]\n",
+		 combiner->parent_irq, combiner->nirqs, combiner->regs[0].addr);
+	return 0;
+}
+
+static const struct acpi_device_id qcom_irq_combiner_ids[] = {
+	{ "QCOM80B1", },
+	{ }
+};
+
+static struct platform_driver qcom_irq_combiner_probe = {
+	.driver = {
+		.name = "qcom-irq-combiner",
+		.acpi_match_table = ACPI_PTR(qcom_irq_combiner_ids),
+	},
+	.probe = combiner_probe,
+};
+
+static int __init register_qcom_irq_combiner(void)
+{
+	return platform_driver_register(&qcom_irq_combiner_probe);
+}
+device_initcall(register_qcom_irq_combiner);
-- 
Qualcomm Datacenter Technologies, Inc. on behalf of the Qualcomm Technologies, Inc.
Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.

Re: [PATCH V12 1/3] ACPI: Generic GSI: Do not attempt to map non-GSI IRQs during bus scan

[Lorenzo Pieralisi]

On Thu, Feb 02, 2017 at 06:23:57PM -0500, Agustin Vega-Frias wrote:
> ACPI extended IRQ resources may contain a Resource Source field to specify
> an alternate interrupt controller, attempting to map them as GSIs is
> incorrect, so just disable the platform resource.
> 
> Since this field is currently ignored, we make this change conditional
> on CONFIG_ACPI_GENERIC_GSI to keep the current behavior on x86 platforms,
> in case some existing ACPI tables are using this incorrectly.
> 
> Acked-by: Rafael J. Wysocki <rafael@kernel.org>
> Signed-off-by: Agustin Vega-Frias <agustinv@codeaurora.org>
> ---
>  drivers/acpi/resource.c | 18 +++++++++++++++++-
>  1 file changed, 17 insertions(+), 1 deletion(-)

Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>

> diff --git a/drivers/acpi/resource.c b/drivers/acpi/resource.c
> index cb57962..8b11d6d 100644
> --- a/drivers/acpi/resource.c
> +++ b/drivers/acpi/resource.c
> @@ -43,6 +43,19 @@ static inline bool acpi_iospace_resource_valid(struct resource *res)
>  acpi_iospace_resource_valid(struct resource *res) { return true; }
>  #endif
>  
> +#if IS_ENABLED(CONFIG_ACPI_GENERIC_GSI)
> +static inline bool is_gsi(struct acpi_resource_extended_irq *ext_irq)
> +{
> +	return ext_irq->resource_source.string_length == 0 &&
> +	       ext_irq->producer_consumer == ACPI_CONSUMER;
> +}
> +#else
> +static inline bool is_gsi(struct acpi_resource_extended_irq *ext_irq)
> +{
> +	return true;
> +}
> +#endif
> +
>  static bool acpi_dev_resource_len_valid(u64 start, u64 end, u64 len, bool io)
>  {
>  	u64 reslen = end - start + 1;
> @@ -470,9 +483,12 @@ bool acpi_dev_resource_interrupt(struct acpi_resource *ares, int index,
>  			acpi_dev_irqresource_disabled(res, 0);
>  			return false;
>  		}
> -		acpi_dev_get_irqresource(res, ext_irq->interrupts[index],
> +		if (is_gsi(ext_irq))
> +			acpi_dev_get_irqresource(res, ext_irq->interrupts[index],
>  					 ext_irq->triggering, ext_irq->polarity,
>  					 ext_irq->sharable, false);
> +		else
> +			acpi_dev_irqresource_disabled(res, 0);
>  		break;
>  	default:
>  		res->flags = 0;
> -- 
> Qualcomm Datacenter Technologies, Inc. on behalf of the Qualcomm Technologies, Inc.
> Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.
> 

Re: [PATCH V12 2/3] ACPI: Add support for ResourceSource/IRQ domain mapping

[Lorenzo Pieralisi]

On Thu, Feb 02, 2017 at 06:23:58PM -0500, Agustin Vega-Frias wrote:
> ACPI extended IRQ resources may contain a ResourceSource to specify
> an alternate interrupt controller. Introduce acpi_irq_get and use it
> to implement ResourceSource/IRQ domain mapping.
> 
> The new API is similar to of_irq_get and allows re-initialization
> of a platform resource from the ACPI extended IRQ resource, and
> provides proper behavior for probe deferral when the domain is not
> yet present when called.
> 
> Acked-by: Rafael J. Wysocki <rafael@kernel.org>
> Signed-off-by: Agustin Vega-Frias <agustinv@codeaurora.org>
> ---
>  drivers/acpi/Makefile         |   2 +-
>  drivers/acpi/{gsi.c => irq.c} | 199 ++++++++++++++++++++++++++++++++++++++++++
>  drivers/base/platform.c       |  10 +++
>  include/linux/acpi.h          |  10 +++
>  4 files changed, 220 insertions(+), 1 deletion(-)
>  rename drivers/acpi/{gsi.c => irq.c} (31%)

Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>

> diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile
> index 9ed0878..a391bbc 100644
> --- a/drivers/acpi/Makefile
> +++ b/drivers/acpi/Makefile
> @@ -55,7 +55,7 @@ acpi-$(CONFIG_DEBUG_FS)		+= debugfs.o
>  acpi-$(CONFIG_ACPI_NUMA)	+= numa.o
>  acpi-$(CONFIG_ACPI_PROCFS_POWER) += cm_sbs.o
>  acpi-y				+= acpi_lpat.o
> -acpi-$(CONFIG_ACPI_GENERIC_GSI) += gsi.o
> +acpi-$(CONFIG_ACPI_GENERIC_GSI) += irq.o
>  acpi-$(CONFIG_ACPI_WATCHDOG)	+= acpi_watchdog.o
>  
>  # These are (potentially) separate modules
> diff --git a/drivers/acpi/gsi.c b/drivers/acpi/irq.c
> similarity index 31%
> rename from drivers/acpi/gsi.c
> rename to drivers/acpi/irq.c
> index ee9e0f2..830299a 100644
> --- a/drivers/acpi/gsi.c
> +++ b/drivers/acpi/irq.c
> @@ -85,6 +85,205 @@ void acpi_unregister_gsi(u32 gsi)
>  EXPORT_SYMBOL_GPL(acpi_unregister_gsi);
>  
>  /**
> + * acpi_get_irq_source_fwhandle() - Retrieve fwhandle from IRQ resource source.
> + * @source: acpi_resource_source to use for the lookup.
> + *
> + * Description:
> + * Retrieve the fwhandle of the device referenced by the given IRQ resource
> + * source.
> + *
> + * Return:
> + * The referenced device fwhandle or NULL on failure
> + */
> +static struct fwnode_handle *
> +acpi_get_irq_source_fwhandle(const struct acpi_resource_source *source)
> +{
> +	struct fwnode_handle *result;
> +	struct acpi_device *device;
> +	acpi_handle handle;
> +	acpi_status status;
> +
> +	if (!source->string_length)
> +		return acpi_gsi_domain_id;
> +
> +	status = acpi_get_handle(NULL, source->string_ptr, &handle);
> +	if (WARN_ON(ACPI_FAILURE(status)))
> +		return NULL;
> +
> +	device = acpi_bus_get_acpi_device(handle);
> +	if (WARN_ON(!device))
> +		return NULL;
> +
> +	result = &device->fwnode;
> +	acpi_bus_put_acpi_device(device);
> +	return result;
> +}
> +
> +/*
> + * Context for the resource walk used to lookup IRQ resources.
> + * Contains a return code, the lookup index, and references to the flags
> + * and fwspec where the result is returned.
> + */
> +struct acpi_irq_parse_one_ctx {
> +	int rc;
> +	unsigned int index;
> +	unsigned long *res_flags;
> +	struct irq_fwspec *fwspec;
> +};
> +
> +/**
> + * acpi_irq_parse_one_match - Handle a matching IRQ resource.
> + * @fwnode: matching fwnode
> + * @hwirq: hardware IRQ number
> + * @triggering: triggering attributes of hwirq
> + * @polarity: polarity attributes of hwirq
> + * @polarity: polarity attributes of hwirq
> + * @shareable: shareable attributes of hwirq
> + * @ctx: acpi_irq_parse_one_ctx updated by this function
> + *
> + * Description:
> + * Handle a matching IRQ resource by populating the given ctx with
> + * the information passed.
> + */
> +static inline void acpi_irq_parse_one_match(struct fwnode_handle *fwnode,
> +					    u32 hwirq, u8 triggering,
> +					    u8 polarity, u8 shareable,
> +					    struct acpi_irq_parse_one_ctx *ctx)
> +{
> +	if (!fwnode)
> +		return;
> +	ctx->rc = 0;
> +	*ctx->res_flags = acpi_dev_irq_flags(triggering, polarity, shareable);
> +	ctx->fwspec->fwnode = fwnode;
> +	ctx->fwspec->param[0] = hwirq;
> +	ctx->fwspec->param[1] = acpi_dev_get_irq_type(triggering, polarity);
> +	ctx->fwspec->param_count = 2;
> +}
> +
> +/**
> + * acpi_irq_parse_one_cb - Handle the given resource.
> + * @ares: resource to handle
> + * @context: context for the walk
> + *
> + * Description:
> + * This is called by acpi_walk_resources passing each resource returned by
> + * the _CRS method. We only inspect IRQ resources. Since IRQ resources
> + * might contain multiple interrupts we check if the index is within this
> + * one's interrupt array, otherwise we subtract the current resource IRQ
> + * count from the lookup index to prepare for the next resource.
> + * Once a match is found we call acpi_irq_parse_one_match to populate
> + * the result and end the walk by returning AE_CTRL_TERMINATE.
> + *
> + * Return:
> + * AE_OK if the walk should continue, AE_CTRL_TERMINATE if a matching
> + * IRQ resource was found.
> + */
> +static acpi_status acpi_irq_parse_one_cb(struct acpi_resource *ares,
> +					 void *context)
> +{
> +	struct acpi_irq_parse_one_ctx *ctx = context;
> +	struct acpi_resource_irq *irq;
> +	struct acpi_resource_extended_irq *eirq;
> +	struct fwnode_handle *fwnode;
> +
> +	switch (ares->type) {
> +	case ACPI_RESOURCE_TYPE_IRQ:
> +		irq = &ares->data.irq;
> +		if (ctx->index >= irq->interrupt_count) {
> +			ctx->index -= irq->interrupt_count;
> +			return AE_OK;
> +		}
> +		fwnode = acpi_gsi_domain_id;
> +		acpi_irq_parse_one_match(fwnode, irq->interrupts[ctx->index],
> +					 irq->triggering, irq->polarity,
> +					 irq->sharable, ctx);
> +		return AE_CTRL_TERMINATE;
> +	case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
> +		eirq = &ares->data.extended_irq;
> +		if (eirq->producer_consumer == ACPI_PRODUCER)
> +			return AE_OK;
> +		if (ctx->index >= eirq->interrupt_count) {
> +			ctx->index -= eirq->interrupt_count;
> +			return AE_OK;
> +		}
> +		fwnode = acpi_get_irq_source_fwhandle(&eirq->resource_source);
> +		acpi_irq_parse_one_match(fwnode, eirq->interrupts[ctx->index],
> +					 eirq->triggering, eirq->polarity,
> +					 eirq->sharable, ctx);
> +		return AE_CTRL_TERMINATE;
> +	}
> +
> +	return AE_OK;
> +}
> +
> +/**
> + * acpi_irq_parse_one - Resolve an interrupt for a device
> + * @handle: the device whose interrupt is to be resolved
> + * @index: index of the interrupt to resolve
> + * @fwspec: structure irq_fwspec filled by this function
> + * @flags: resource flags filled by this function
> + *
> + * Description:
> + * Resolves an interrupt for a device by walking its CRS resources to find
> + * the appropriate ACPI IRQ resource and populating the given struct irq_fwspec
> + * and flags.
> + *
> + * Return:
> + * The result stored in ctx.rc by the callback, or the default -EINVAL value
> + * if an error occurs.
> + */
> +static int acpi_irq_parse_one(acpi_handle handle, unsigned int index,
> +			      struct irq_fwspec *fwspec, unsigned long *flags)
> +{
> +	struct acpi_irq_parse_one_ctx ctx = { -EINVAL, index, flags, fwspec };
> +
> +	acpi_walk_resources(handle, METHOD_NAME__CRS, acpi_irq_parse_one_cb, &ctx);
> +	return ctx.rc;
> +}
> +
> +/**
> + * acpi_irq_get - Lookup an ACPI IRQ resource and use it to initialize resource.
> + * @handle: ACPI device handle
> + * @index:  ACPI IRQ resource index to lookup
> + * @res:    Linux IRQ resource to initialize
> + *
> + * Description:
> + * Look for the ACPI IRQ resource with the given index and use it to initialize
> + * the given Linux IRQ resource.
> + *
> + * Return:
> + * 0 on success
> + * -EINVAL if an error occurs
> + * -EPROBE_DEFER if the IRQ lookup/conversion failed
> + */
> +int acpi_irq_get(acpi_handle handle, unsigned int index, struct resource *res)
> +{
> +	struct irq_fwspec fwspec;
> +	struct irq_domain *domain;
> +	unsigned long flags;
> +	int rc;
> +
> +	rc = acpi_irq_parse_one(handle, index, &fwspec, &flags);
> +	if (rc)
> +		return rc;
> +
> +	domain = irq_find_matching_fwnode(fwspec.fwnode, DOMAIN_BUS_ANY);
> +	if (!domain)
> +		return -EPROBE_DEFER;
> +
> +	rc = irq_create_fwspec_mapping(&fwspec);
> +	if (rc <= 0)
> +		return -EINVAL;
> +
> +	res->start = rc;
> +	res->end = rc;
> +	res->flags = flags;
> +
> +	return 0;
> +}
> +EXPORT_SYMBOL_GPL(acpi_irq_get);
> +
> +/**
>   * acpi_set_irq_model - Setup the GSI irqdomain information
>   * @model: the value assigned to acpi_irq_model
>   * @fwnode: the irq_domain identifier for mapping and looking up
> diff --git a/drivers/base/platform.c b/drivers/base/platform.c
> index c4af003..647e476 100644
> --- a/drivers/base/platform.c
> +++ b/drivers/base/platform.c
> @@ -102,6 +102,16 @@ int platform_get_irq(struct platform_device *dev, unsigned int num)
>  	}
>  
>  	r = platform_get_resource(dev, IORESOURCE_IRQ, num);
> +	if (has_acpi_companion(&dev->dev)) {
> +		if (r && r->flags & IORESOURCE_DISABLED) {
> +			int ret;
> +
> +			ret = acpi_irq_get(ACPI_HANDLE(&dev->dev), num, r);
> +			if (ret)
> +				return ret;
> +		}
> +	}
> +
>  	/*
>  	 * The resources may pass trigger flags to the irqs that need
>  	 * to be set up. It so happens that the trigger flags for
> diff --git a/include/linux/acpi.h b/include/linux/acpi.h
> index 5b36974..8e577c2 100644
> --- a/include/linux/acpi.h
> +++ b/include/linux/acpi.h
> @@ -1153,4 +1153,14 @@ static inline void acpi_table_upgrade(void) { }
>  static inline int parse_spcr(bool earlycon) { return 0; }
>  #endif
>  
> +#if IS_ENABLED(CONFIG_ACPI_GENERIC_GSI)
> +int acpi_irq_get(acpi_handle handle, unsigned int index, struct resource *res);
> +#else
> +static inline
> +int acpi_irq_get(acpi_handle handle, unsigned int index, struct resource *res)
> +{
> +	return -EINVAL;
> +}
> +#endif
> +
>  #endif	/*_LINUX_ACPI_H*/
> -- 
> Qualcomm Datacenter Technologies, Inc. on behalf of the Qualcomm Technologies, Inc.
> Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.
> 

Re: [PATCH V12 0/3] irqchip: qcom: Add IRQ combiner driver

[Hanjun Guo]

On 2017/2/3 7:23, Agustin Vega-Frias wrote:
> Add support for IRQ combiners in the Top-level Control and Status
> Registers (TCSR) hardware block in Qualcomm Technologies chips.
>
> The first patch prevents the ACPI core from attempting to map IRQ resources
> with a valid ResourceSource as GSIs.
>
> The second patch adds support for ResourceSource/IRQ domain mapping and
> fixes IRQ probe deferral by allowing platform_device IRQ resources to be
> re-initialized from the corresponding ACPI IRQ resource.
>
> Both changes described above are conditional on the ACPI_GENERIC_GSI config.
>
> The third patch takes advantage of the new capabilities to implement
> the driver for the IRQ combiners.
>
> Tested on top of v4.10-rc6.
>
> Changes V11 -> V12:
> * Remove probe table, add that optimization later.
> * Fix some minor style issues.

For patch [1-2/3], I tested on x86 and IA64 machine, didn't see
regressions in dmesg, and tested them on Hisilicon D03 (ARM64 with
mbigen irqchip which needs this mechanism) , it works fine.

Tested-by: Hanjun Guo <hanjun.guo@linaro.org>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>

Thanks
Hanjun