[PATCH v6 0/2] irqchip: qcom: add support for PDC interrupt controller

[PATCH v6 0/2] irqchip: qcom: add support for PDC interrupt controller

[Lina Iyer]

Changes since v5:
- Fixed comment style of SPDX

Changes since v4:
- Code clean up as suggested by Marc

On newer Qualcomm Techonologies Inc's SoCs like the SDM845, the GIC is in a
power domain that can be powered off when not needed. Interrupts that need to
be sensed even when the GIC is powered off, are routed through an interrupt
controller in an always-on domain called the Power Domain Controller a.k.a PDC.
This series adds support for the PDC's interrupt controller.

Please consider reviewing these patches.

RFC v1: https://patchwork.kernel.org/patch/10180857/
RFC v2: https://www.mail-archive.com/linux-kernel@vger.kernel.org/msg1600634.html
v3: https://lkml.org/lkml/2018/2/6/595
v4: https://www.spinics.net/lists/linux-arm-msm/msg32906.html

Lina Iyer (2):
  drivers: irqchip: pdc: Add PDC interrupt controller for QCOM SoCs
  dt-bindings/interrupt-controller: pdc: descibe PDC device binding

 .../bindings/interrupt-controller/qcom,pdc.txt     |  78 +++++
 drivers/irqchip/Kconfig                            |   9 +
 drivers/irqchip/Makefile                           |   1 +
 drivers/irqchip/qcom-pdc.c                         | 314 +++++++++++++++++++++
 4 files changed, 402 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/interrupt-controller/qcom,pdc.txt
 create mode 100644 drivers/irqchip/qcom-pdc.c

--
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project

[PATCH v6 1/2] drivers: irqchip: pdc: Add PDC interrupt controller for QCOM SoCs

[Lina Iyer]

>From : Archana Sathyakumar <asathyak@codeaurora.org>

The Power Domain Controller (PDC) on QTI SoCs like SDM845 houses an
interrupt controller along with other domain control functions to handle
interrupt related functions like handle falling edge or active low which
are not detected at the GIC and handle wakeup interrupts.

The interrupt controller is on an always-on domain for the purpose of
waking up the processor. Only a subset of the processor's interrupts are
routed through the PDC to the GIC. The PDC powers on the processors'
domain, when in low power mode and replays pending interrupts so the GIC
may wake up the processor.

Signed-off-by: Archana Sathyakumar <asathyak@codeaurora.org>
Signed-off-by: Lina Iyer <ilina@codeaurora.org>
---
 drivers/irqchip/Kconfig    |   9 ++
 drivers/irqchip/Makefile   |   1 +
 drivers/irqchip/qcom-pdc.c | 314 +++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 324 insertions(+)
 create mode 100644 drivers/irqchip/qcom-pdc.c

diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index c70476b34a53..506c6aa7f0b4 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -343,4 +343,13 @@ config MESON_IRQ_GPIO
        help
          Support Meson SoC Family GPIO Interrupt Multiplexer
 
+config QCOM_PDC
+	bool "QCOM PDC"
+	depends on ARCH_QCOM
+	select IRQ_DOMAIN
+	select IRQ_DOMAIN_HIERARCHY
+	help
+	  Power Domain Controller driver to manage and configure wakeup
+	  IRQs for Qualcomm Technologies Inc (QTI) mobile chips.
+
 endmenu
diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
index d2df34a54d38..280723d83916 100644
--- a/drivers/irqchip/Makefile
+++ b/drivers/irqchip/Makefile
@@ -84,3 +84,4 @@ obj-$(CONFIG_QCOM_IRQ_COMBINER)		+= qcom-irq-combiner.o
 obj-$(CONFIG_IRQ_UNIPHIER_AIDET)	+= irq-uniphier-aidet.o
 obj-$(CONFIG_ARCH_SYNQUACER)		+= irq-sni-exiu.o
 obj-$(CONFIG_MESON_IRQ_GPIO)		+= irq-meson-gpio.o
+obj-$(CONFIG_QCOM_PDC)			+= qcom-pdc.o
diff --git a/drivers/irqchip/qcom-pdc.c b/drivers/irqchip/qcom-pdc.c
new file mode 100644
index 000000000000..714e95858837
--- /dev/null
+++ b/drivers/irqchip/qcom-pdc.c
@@ -0,0 +1,314 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2017-2018, The Linux Foundation. All rights reserved.
+ */
+
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/irq.h>
+#include <linux/irqchip.h>
+#include <linux/irqdomain.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_device.h>
+#include <linux/spinlock.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+
+#define PDC_MAX_IRQS		126
+
+#define CLEAR_INTR(reg, intr)	(reg & ~(1 << intr))
+#define ENABLE_INTR(reg, intr)	(reg | (1 << intr))
+
+#define IRQ_ENABLE_BANK		0x10
+#define IRQ_i_CFG		0x110
+
+struct pdc_pin_region {
+	u32 pin_base;
+	u32 parent_base;
+	u32 cnt;
+};
+
+static DEFINE_RAW_SPINLOCK(pdc_lock);
+static void __iomem *pdc_base;
+static struct pdc_pin_region *pdc_region;
+static int pdc_region_cnt;
+
+static void pdc_reg_write(int reg, u32 i, u32 val)
+{
+	writel_relaxed(val, pdc_base + reg + i * sizeof(u32));
+}
+
+static u32 pdc_reg_read(int reg, u32 i)
+{
+	return readl_relaxed(pdc_base + reg + i * sizeof(u32));
+}
+
+static void pdc_enable_intr(struct irq_data *d, bool on)
+{
+	int pin_out = d->hwirq;
+	u32 index, mask;
+	u32 enable;
+
+	index = pin_out / 32;
+	mask = pin_out % 32;
+
+	raw_spin_lock(&pdc_lock);
+	enable = pdc_reg_read(IRQ_ENABLE_BANK, index);
+	enable = on ? ENABLE_INTR(enable, mask) : CLEAR_INTR(enable, mask);
+	pdc_reg_write(IRQ_ENABLE_BANK, index, enable);
+	raw_spin_unlock(&pdc_lock);
+}
+
+static void qcom_pdc_gic_mask(struct irq_data *d)
+{
+	pdc_enable_intr(d, false);
+	irq_chip_mask_parent(d);
+}
+
+static void qcom_pdc_gic_unmask(struct irq_data *d)
+{
+	pdc_enable_intr(d, true);
+	irq_chip_unmask_parent(d);
+}
+
+/*
+ * GIC does not handle falling edge or active low. To allow falling edge and
+ * active low interrupts to be handled at GIC, PDC has an inverter that inverts
+ * falling edge into a rising edge and active low into an active high.
+ * For the inverter to work, the polarity bit in the IRQ_CONFIG register has to
+ * set as per the table below.
+ * (polarity, falling edge, rising edge ) POLARITY
+ * 3'b0 00  Level sensitive active low    LOW
+ * 3'b0 01  Rising edge sensitive         NOT USED
+ * 3'b0 10  Falling edge sensitive        LOW
+ * 3'b0 11  Dual Edge sensitive           NOT USED
+ * 3'b1 00  Level sensitive active High   HIGH
+ * 3'b1 01  Falling Edge sensitive        NOT USED
+ * 3'b1 10  Rising edge sensitive         HIGH
+ * 3'b1 11  Dual Edge sensitive           HIGH
+ */
+enum pdc_irq_config_bits {
+	PDC_POLARITY_LOW	= 0,
+	PDC_FALLING_EDGE	= 2,
+	PDC_POLARITY_HIGH	= 4,
+	PDC_RISING_EDGE		= 6,
+	PDC_DUAL_EDGE		= 7,
+};
+
+/**
+ * qcom_pdc_gic_set_type: Configure PDC for the interrupt
+ *
+ * @d: the interrupt data
+ * @type: the interrupt type
+ *
+ * If @type is edge triggered, forward that as Rising edge as PDC
+ * takes care of converting falling edge to rising edge signal
+ * If @type is level, then forward that as level high as PDC
+ * takes care of converting falling edge to rising edge signal
+ */
+static int qcom_pdc_gic_set_type(struct irq_data *d, unsigned int type)
+{
+	int pin_out = d->hwirq;
+	enum pdc_irq_config_bits pdc_type;
+
+	switch (type) {
+	case IRQ_TYPE_EDGE_RISING:
+		pdc_type = PDC_RISING_EDGE;
+		type = IRQ_TYPE_EDGE_RISING;
+		break;
+	case IRQ_TYPE_EDGE_FALLING:
+		pdc_type = PDC_FALLING_EDGE;
+		type = IRQ_TYPE_EDGE_RISING;
+		break;
+	case IRQ_TYPE_EDGE_BOTH:
+		pdc_type = PDC_DUAL_EDGE;
+		break;
+	case IRQ_TYPE_LEVEL_HIGH:
+		pdc_type = PDC_POLARITY_HIGH;
+		type = IRQ_TYPE_LEVEL_HIGH;
+		break;
+	case IRQ_TYPE_LEVEL_LOW:
+		pdc_type = PDC_POLARITY_LOW;
+		type = IRQ_TYPE_LEVEL_HIGH;
+		break;
+	default:
+		WARN_ON(1);
+		return -EINVAL;
+	}
+
+	pdc_reg_write(IRQ_i_CFG, pin_out, pdc_type);
+
+	return irq_chip_set_type_parent(d, type);
+}
+
+static struct irq_chip qcom_pdc_gic_chip = {
+	.name			= "PDC",
+	.irq_eoi		= irq_chip_eoi_parent,
+	.irq_mask		= qcom_pdc_gic_mask,
+	.irq_unmask		= qcom_pdc_gic_unmask,
+	.irq_retrigger		= irq_chip_retrigger_hierarchy,
+	.irq_set_type		= qcom_pdc_gic_set_type,
+	.flags			= IRQCHIP_MASK_ON_SUSPEND |
+				  IRQCHIP_SET_TYPE_MASKED |
+				  IRQCHIP_SKIP_SET_WAKE,
+	.irq_set_vcpu_affinity	= irq_chip_set_vcpu_affinity_parent,
+	.irq_set_affinity	= irq_chip_set_affinity_parent,
+};
+
+static irq_hw_number_t get_parent_hwirq(int pin)
+{
+	int i;
+	struct pdc_pin_region *region;
+
+	for (i = 0; i < pdc_region_cnt; i++) {
+		region = &pdc_region[i];
+		if (pin >= region->pin_base &&
+		   pin < region->pin_base + region->cnt)
+			return (region->parent_base + pin - region->pin_base);
+	}
+
+	WARN_ON(1);
+	return ~0UL;
+}
+
+static int qcom_pdc_translate(struct irq_domain *d,
+	struct irq_fwspec *fwspec, unsigned long *hwirq, unsigned int *type)
+{
+	if (is_of_node(fwspec->fwnode)) {
+		if (fwspec->param_count != 2)
+			return -EINVAL;
+
+		*hwirq = fwspec->param[0];
+		*type = fwspec->param[1] & IRQ_TYPE_SENSE_MASK;
+		return 0;
+	}
+
+	return -EINVAL;
+}
+
+static int qcom_pdc_alloc(struct irq_domain *domain,
+			unsigned int virq, unsigned int nr_irqs, void *data)
+{
+	struct irq_fwspec *fwspec = data;
+	struct irq_fwspec parent_fwspec;
+	irq_hw_number_t hwirq, parent_hwirq;
+	unsigned int type;
+	int ret;
+
+	ret = qcom_pdc_translate(domain, fwspec, &hwirq, &type);
+	if (ret)
+		return -EINVAL;
+
+	parent_hwirq = get_parent_hwirq(hwirq);
+	if (parent_hwirq == ~0UL)
+		return -EINVAL;
+
+	ret  = irq_domain_set_hwirq_and_chip(domain, virq, hwirq,
+					    &qcom_pdc_gic_chip, NULL);
+	if (ret)
+		return ret;
+
+	if (type & IRQ_TYPE_EDGE_BOTH)
+		type = IRQ_TYPE_EDGE_RISING;
+
+	if (type & IRQ_TYPE_LEVEL_MASK)
+		type = IRQ_TYPE_LEVEL_HIGH;
+
+	parent_fwspec.fwnode      = domain->parent->fwnode;
+	parent_fwspec.param_count = 3;
+	parent_fwspec.param[0]    = 0;
+	parent_fwspec.param[1]    = parent_hwirq;
+	parent_fwspec.param[2]    = type;
+
+	return irq_domain_alloc_irqs_parent(domain, virq, nr_irqs,
+					   &parent_fwspec);
+}
+
+static const struct irq_domain_ops qcom_pdc_ops = {
+	.translate	= qcom_pdc_translate,
+	.alloc		= qcom_pdc_alloc,
+	.free		= irq_domain_free_irqs_common,
+};
+
+static int pdc_setup_pin_mapping(struct device_node *np)
+{
+	int ret, n;
+
+	n = of_property_count_elems_of_size(np, "qcom,pdc-ranges", sizeof(u32));
+	if (n <= 0 || n % 3)
+		return -EINVAL;
+
+	pdc_region_cnt = n / 3;
+	pdc_region = kcalloc(pdc_region_cnt, sizeof(*pdc_region), GFP_KERNEL);
+	if (!pdc_region) {
+		pdc_region_cnt = 0;
+		return -ENOMEM;
+	}
+
+	for (n = 0; n < pdc_region_cnt; n++) {
+		ret = of_property_read_u32_index(np, "qcom,pdc-ranges",
+						n * 3 + 0,
+						&pdc_region[n].pin_base);
+		if (ret)
+			return ret;
+		ret = of_property_read_u32_index(np, "qcom,pdc-ranges",
+						n * 3 + 1,
+						&pdc_region[n].parent_base);
+		if (ret)
+			return ret;
+		ret = of_property_read_u32_index(np, "qcom,pdc-ranges",
+						n * 3 + 2,
+						&pdc_region[n].cnt);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+static int qcom_pdc_init(struct device_node *node, struct device_node *parent)
+{
+	struct irq_domain *parent_domain, *pdc_domain;
+	int ret;
+
+	pdc_base = of_iomap(node, 0);
+	if (!pdc_base) {
+		pr_err("%pOF: unable to map PDC registers\n", node);
+		return -ENXIO;
+	}
+
+	parent_domain = irq_find_host(parent);
+	if (!parent_domain) {
+		pr_err("%pOF: unable to find PDC's parent domain\n", node);
+		ret = -ENXIO;
+		goto fail;
+	}
+
+	ret = pdc_setup_pin_mapping(node);
+	if (ret) {
+		pr_err("%pOF: failed to init PDC pin-hwirq mapping\n", node);
+		goto fail;
+	}
+
+	pdc_domain = irq_domain_create_hierarchy(parent_domain, 0, PDC_MAX_IRQS,
+						of_fwnode_handle(node),
+						&qcom_pdc_ops, NULL);
+	if (!pdc_domain) {
+		pr_err("%pOF: GIC domain add failed\n", node);
+		ret = -ENOMEM;
+		goto fail;
+	}
+
+	return 0;
+
+fail:
+	kfree(pdc_region);
+	iounmap(pdc_base);
+	return ret;
+}
+
+IRQCHIP_DECLARE(pdc_sdm845, "qcom,sdm845-pdc", qcom_pdc_init);
-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project

Re: [PATCH v6 1/2] drivers: irqchip: pdc: Add PDC interrupt controller for QCOM SoCs

[Thomas Gleixner]

On Fri, 9 Feb 2018, Lina Iyer wrote:
> +/*
> + * GIC does not handle falling edge or active low. To allow falling edge and
> + * active low interrupts to be handled at GIC, PDC has an inverter that inverts
> + * falling edge into a rising edge and active low into an active high.
> + * For the inverter to work, the polarity bit in the IRQ_CONFIG register has to
> + * set as per the table below.
> + * (polarity, falling edge, rising edge ) POLARITY
> + * 3'b0 00  Level sensitive active low    LOW
> + * 3'b0 01  Rising edge sensitive         NOT USED
> + * 3'b0 10  Falling edge sensitive        LOW
> + * 3'b0 11  Dual Edge sensitive           NOT USED
> + * 3'b1 00  Level sensitive active High   HIGH
> + * 3'b1 01  Falling Edge sensitive        NOT USED
> + * 3'b1 10  Rising edge sensitive         HIGH
> + * 3'b1 11  Dual Edge sensitive           HIGH
> + */
> +enum pdc_irq_config_bits {
> +	PDC_POLARITY_LOW	= 0,
> +	PDC_FALLING_EDGE	= 2,
> +	PDC_POLARITY_HIGH	= 4,
> +	PDC_RISING_EDGE		= 6,
> +	PDC_DUAL_EDGE		= 7,

My previous comment about using binary constants still stands. Please
either address review comments or reply at least. Ignoring reviews is not
an option.

Aside of that I really have to ask about the naming of these constants. Are
these names hardware register nomenclature? If yes, they are disgusting. If
no, they are still disgusting, but should be changed to sensible ones,
which just match the IRQ_TYPE naming convention.

    PDC_LEVEL_LOW	= 000b,
    PDC_EDGE_FALLING	= 010b,
    ....


> +	switch (type) {
> +	case IRQ_TYPE_EDGE_RISING:
> +		pdc_type = PDC_RISING_EDGE;
> +		type = IRQ_TYPE_EDGE_RISING;

Whats the point of assigning the same value again?

> +		break;
> +	case IRQ_TYPE_EDGE_FALLING:
> +		pdc_type = PDC_FALLING_EDGE;
> +		type = IRQ_TYPE_EDGE_RISING;
> +		break;
> +	case IRQ_TYPE_EDGE_BOTH:
> +		pdc_type = PDC_DUAL_EDGE;
> +		break;
> +	case IRQ_TYPE_LEVEL_HIGH:
> +		pdc_type = PDC_POLARITY_HIGH;
> +		type = IRQ_TYPE_LEVEL_HIGH;

Ditto

Thanks,

	tglx

Re: [PATCH v6 1/2] drivers: irqchip: pdc: Add PDC interrupt controller for QCOM SoCs

[Lina Iyer]

On Mon, Feb 12 2018 at 13:40 +0000, Thomas Gleixner wrote:
>On Fri, 9 Feb 2018, Lina Iyer wrote:
>> +/*
>> + * GIC does not handle falling edge or active low. To allow falling edge and
>> + * active low interrupts to be handled at GIC, PDC has an inverter that inverts
>> + * falling edge into a rising edge and active low into an active high.
>> + * For the inverter to work, the polarity bit in the IRQ_CONFIG register has to
>> + * set as per the table below.
>> + * (polarity, falling edge, rising edge ) POLARITY
>> + * 3'b0 00  Level sensitive active low    LOW
>> + * 3'b0 01  Rising edge sensitive         NOT USED
>> + * 3'b0 10  Falling edge sensitive        LOW
>> + * 3'b0 11  Dual Edge sensitive           NOT USED
>> + * 3'b1 00  Level sensitive active High   HIGH
>> + * 3'b1 01  Falling Edge sensitive        NOT USED
>> + * 3'b1 10  Rising edge sensitive         HIGH
>> + * 3'b1 11  Dual Edge sensitive           HIGH
>> + */
>> +enum pdc_irq_config_bits {
>> +	PDC_POLARITY_LOW	= 0,
>> +	PDC_FALLING_EDGE	= 2,
>> +	PDC_POLARITY_HIGH	= 4,
>> +	PDC_RISING_EDGE		= 6,
>> +	PDC_DUAL_EDGE		= 7,
>
>My previous comment about using binary constants still stands. Please
>either address review comments or reply at least. Ignoring reviews is not
>an option.
>
I removed them from the enum definitions. Will remove them from the
comments as well. Sorry. It was not my intention to ignore any review
comments.

>Aside of that I really have to ask about the naming of these constants. Are
>these names hardware register nomenclature? If yes, they are disgusting. If
>no, they are still disgusting, but should be changed to sensible ones,
>which just match the IRQ_TYPE naming convention.
>
>    PDC_LEVEL_LOW	= 000b,
>    PDC_EDGE_FALLING	= 010b,
>    ....
>
>
They are named that way in spec :) Will change.

>> +	switch (type) {
>> +	case IRQ_TYPE_EDGE_RISING:
>> +		pdc_type = PDC_RISING_EDGE;
>> +		type = IRQ_TYPE_EDGE_RISING;
>
>Whats the point of assigning the same value again?
>
Failed to notice. Will fix.

Thanks,
Lina

>> +		break;
>> +	case IRQ_TYPE_EDGE_FALLING:
>> +		pdc_type = PDC_FALLING_EDGE;
>> +		type = IRQ_TYPE_EDGE_RISING;
>> +		break;
>> +	case IRQ_TYPE_EDGE_BOTH:
>> +		pdc_type = PDC_DUAL_EDGE;
>> +		break;
>> +	case IRQ_TYPE_LEVEL_HIGH:
>> +		pdc_type = PDC_POLARITY_HIGH;
>> +		type = IRQ_TYPE_LEVEL_HIGH;
>
>Ditto
>
>Thanks,
>
>	tglx

Re: [PATCH v6 1/2] drivers: irqchip: pdc: Add PDC interrupt controller for QCOM SoCs

[Lina Iyer]

On Mon, Feb 12 2018 at 13:40 +0000, Thomas Gleixner wrote:
>On Fri, 9 Feb 2018, Lina Iyer wrote:
>> +enum pdc_irq_config_bits {
>> +	PDC_POLARITY_LOW	= 0,
>> +	PDC_FALLING_EDGE	= 2,
>> +	PDC_POLARITY_HIGH	= 4,
>> +	PDC_RISING_EDGE		= 6,
>> +	PDC_DUAL_EDGE		= 7,
>
>My previous comment about using binary constants still stands. Please
>either address review comments or reply at least. Ignoring reviews is not
>an option.
>
>Aside of that I really have to ask about the naming of these constants. Are
>these names hardware register nomenclature? If yes, they are disgusting. If
>no, they are still disgusting, but should be changed to sensible ones,
>which just match the IRQ_TYPE naming convention.
>
>    PDC_LEVEL_LOW	= 000b,
>    PDC_EDGE_FALLING	= 010b,
>    ....
>
>
Checkpatch doesn't like binary constants. I guess I will need to keep
the enum definitions in hex or decimal. I will remove the binary from
the comments though.

commit 95e2c6023b0e4c8499fb521697f79215f69135fe
Author: Joe Perches <joe@perches.com>
Date:   Wed Jul 3 15:05:20 2013 -0700

    checkpatch: warn when using gcc's binary constant ("0b") extension

    The gcc extension for binary constants that start with 0b is only
    supported with gcc version 4.3 or higher.

    The kernel can still be compiled with earlier versions of gcc, so have
    checkpatch emit a warning for these constants.

    Restructure checkpatch's constant finding code a bit to support finding
    these binary constants.

    Signed-off-by: Joe Perches <joe@perches.com>
    Suggested-by: Andrew Morton <akpm@linux-foundation.org>
    Cc: Andy Whitcroft <apw@canonical.com>
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
    Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>


Thanks,
Lina

Re: [PATCH v6 1/2] drivers: irqchip: pdc: Add PDC interrupt controller for QCOM SoCs

[Thomas Gleixner]

On Thu, 15 Feb 2018, Lina Iyer wrote:
> On Mon, Feb 12 2018 at 13:40 +0000, Thomas Gleixner wrote:
> > On Fri, 9 Feb 2018, Lina Iyer wrote:
> > > +enum pdc_irq_config_bits {
> > > +	PDC_POLARITY_LOW	= 0,
> > > +	PDC_FALLING_EDGE	= 2,
> > > +	PDC_POLARITY_HIGH	= 4,
> > > +	PDC_RISING_EDGE		= 6,
> > > +	PDC_DUAL_EDGE		= 7,
> > 
> > My previous comment about using binary constants still stands. Please
> > either address review comments or reply at least. Ignoring reviews is not
> > an option.
> > 
> > Aside of that I really have to ask about the naming of these constants. Are
> > these names hardware register nomenclature? If yes, they are disgusting. If
> > no, they are still disgusting, but should be changed to sensible ones,
> > which just match the IRQ_TYPE naming convention.
> > 
> >    PDC_LEVEL_LOW	= 000b,
> >    PDC_EDGE_FALLING	= 010b,
> >    ....
> > 
> > 
> Checkpatch doesn't like binary constants. I guess I will need to keep
> the enum definitions in hex or decimal. I will remove the binary from
> the comments though.

Well checkpatch is not always right.

> 
> commit 95e2c6023b0e4c8499fb521697f79215f69135fe
> Author: Joe Perches <joe@perches.com>
> Date:   Wed Jul 3 15:05:20 2013 -0700
> 
>    checkpatch: warn when using gcc's binary constant ("0b") extension
> 
>    The gcc extension for binary constants that start with 0b is only
>    supported with gcc version 4.3 or higher.

Can anything of this be compiled with gcc < 4.3?  

Thanks,

	tglx

Re: [PATCH v6 1/2] drivers: irqchip: pdc: Add PDC interrupt controller for QCOM SoCs

[Lina Iyer]

On Thu, Feb 15 2018 at 20:24 +0000, Thomas Gleixner wrote:
>On Thu, 15 Feb 2018, Lina Iyer wrote:
>> On Mon, Feb 12 2018 at 13:40 +0000, Thomas Gleixner wrote:
>> > On Fri, 9 Feb 2018, Lina Iyer wrote:
>> > > +enum pdc_irq_config_bits {
>> > > +	PDC_POLARITY_LOW	= 0,
>> > > +	PDC_FALLING_EDGE	= 2,
>> > > +	PDC_POLARITY_HIGH	= 4,
>> > > +	PDC_RISING_EDGE		= 6,
>> > > +	PDC_DUAL_EDGE		= 7,
>> >
>> > My previous comment about using binary constants still stands. Please
>> > either address review comments or reply at least. Ignoring reviews is not
>> > an option.
>> >
>> > Aside of that I really have to ask about the naming of these constants. Are
>> > these names hardware register nomenclature? If yes, they are disgusting. If
>> > no, they are still disgusting, but should be changed to sensible ones,
>> > which just match the IRQ_TYPE naming convention.
>> >
>> >    PDC_LEVEL_LOW	= 000b,
>> >    PDC_EDGE_FALLING	= 010b,
>> >    ....
>> >
>> >
>> Checkpatch doesn't like binary constants. I guess I will need to keep
>> the enum definitions in hex or decimal. I will remove the binary from
>> the comments though.
>
>Well checkpatch is not always right.
>
>>
>> commit 95e2c6023b0e4c8499fb521697f79215f69135fe
>> Author: Joe Perches <joe@perches.com>
>> Date:   Wed Jul 3 15:05:20 2013 -0700
>>
>>    checkpatch: warn when using gcc's binary constant ("0b") extension
>>
>>    The gcc extension for binary constants that start with 0b is only
>>    supported with gcc version 4.3 or higher.
>
>Can anything of this be compiled with gcc < 4.3?
>
I don't see a reason why this would be compiled with a older GCC. I am
okay with ignoring the checkpatch errors. I was just not sure if I
should.

Thanks,
Lina

[PATCH v6 2/2] dt-bindings/interrupt-controller: pdc: descibe PDC device binding

[Lina Iyer]

From: Archana Sathyakumar <asathyak@codeaurora.org>

Add device binding documentation for the PDC Interrupt controller on
QCOM SoC's like the SDM845. The interrupt-controller can be used to
sense edge low interrupts and wakeup interrupts when the GIC is
non-operational.

Cc: devicetree@vger.kernel.org
Signed-off-by: Archana Sathyakumar <asathyak@codeaurora.org>
Signed-off-by: Lina Iyer <ilina@codeaurora.org>
---
 .../bindings/interrupt-controller/qcom,pdc.txt     | 78 ++++++++++++++++++++++
 1 file changed, 78 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/interrupt-controller/qcom,pdc.txt

diff --git a/Documentation/devicetree/bindings/interrupt-controller/qcom,pdc.txt b/Documentation/devicetree/bindings/interrupt-controller/qcom,pdc.txt
new file mode 100644
index 000000000000..0b2c97ddb520
--- /dev/null
+++ b/Documentation/devicetree/bindings/interrupt-controller/qcom,pdc.txt
@@ -0,0 +1,78 @@
+PDC interrupt controller
+
+Qualcomm Technologies Inc. SoCs based on the RPM Hardened architecture have a
+Power Domain Controller (PDC) that is on always-on domain. In addition to
+providing power control for the power domains, the hardware also has an
+interrupt controller that can be used to help detect edge low interrupts as
+well detect interrupts when the GIC is non-operational.
+
+GIC is parent interrupt controller at the highest level. Platform interrupt
+controller PDC is next in hierarchy, followed by others. Drivers requiring
+wakeup capabilities of their device interrupts routed through the PDC, must
+specify PDC as their interrupt controller and request the PDC port associated
+with the GIC interrupt. See example below.
+
+Properties:
+
+- compatible:
+	Usage: required
+	Value type: <string>
+	Definition: Should contain "qcom,<soc>-pdc"
+		    - "qcom,sdm845-pdc": For SDM845
+
+- reg:
+	Usage: required
+	Value type: <prop-encoded-array>
+	Definition: Specifies the base physical address for PDC hardware.
+
+- interrupt-cells:
+	Usage: required
+	Value type: <u32>
+	Definition: Specifies the number of cells needed to encode an interrupt
+		    source.
+		    Must be 2.
+		    The first element of the tuple is the PDC pin for the
+		    interrupt.
+		    The second element is the trigger type.
+
+- interrupt-parent:
+	Usage: required
+	Value type: <phandle>
+	Definition: Specifies the interrupt parent necessary for hierarchical
+		    domain to operate.
+
+- interrupt-controller:
+	Usage: required
+	Value type: <bool>
+	Definition: Identifies the node as an interrupt controller.
+
+- qcom,pdc-ranges:
+	Usage: required
+	Value type: <u32 array>
+	Definition: Specifies the PDC pin offset and the number of PDC ports.
+		    The tuples indicates the valid mapping of valid PDC ports
+		    and their hwirq mapping.
+		    The first element of the tuple is the starting PDC port.
+		    The second element is the GIC hwirq number for the PDC port.
+		    The third element is the number of interrupts in sequence.
+
+Example:
+
+	pdc: interrupt-controller@b220000 {
+		compatible = "qcom,sdm845-pdc";
+		reg = <0xb220000 0x30000>;
+		qcom,pdc-ranges = <0 512 94>, <94 641 15>, <115 662 7>;
+		#interrupt-cells = <2>;
+		interrupt-parent = <&intc>;
+		interrupt-controller;
+	};
+
+DT binding of a device that wants to use the GIC SPI 514 as a wakeup
+interrupt, must do -
+
+	wake-device {
+		interrupts-extended = <&pdc 2 IRQ_TYPE_LEVEL_HIGH>;
+	};
+
+In this case interrupt 514 would be mapped to port 2 on the PDC as defined by
+the qcom,pdc-ranges property.
-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project

Re: [PATCH v6 2/2] dt-bindings/interrupt-controller: pdc: descibe PDC device binding

[Rob Herring]

On Fri, Feb 09, 2018 at 09:57:35AM -0700, Lina Iyer wrote:
> From: Archana Sathyakumar <asathyak@codeaurora.org>
> 
> Add device binding documentation for the PDC Interrupt controller on
> QCOM SoC's like the SDM845. The interrupt-controller can be used to
> sense edge low interrupts and wakeup interrupts when the GIC is
> non-operational.
> 
> Cc: devicetree@vger.kernel.org
> Signed-off-by: Archana Sathyakumar <asathyak@codeaurora.org>
> Signed-off-by: Lina Iyer <ilina@codeaurora.org>
> ---
>  .../bindings/interrupt-controller/qcom,pdc.txt     | 78 ++++++++++++++++++++++
>  1 file changed, 78 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/interrupt-controller/qcom,pdc.txt

Reviewed-by: Rob Herring <robh@kernel.org>