Hi Marc,

On Wed, Nov 21, 2018 at 08:41:25AM +0000, Marc Zyngier wrote:

On 21/11/2018 03:36, Manivannan Sadhasivam wrote:

quoted

Add interrupt driver for RDA Micro RDA8810PL SoC.

Signed-off-by: Andreas F?rber <afaerber@suse.de>
Signed-off-by: Manivannan Sadhasivam <redacted>
---
 arch/arm/mach-rda/Kconfig      |   1 +
 drivers/irqchip/Kconfig        |   4 ++
 drivers/irqchip/Makefile       |   1 +
 drivers/irqchip/irq-rda-intc.c | 113 +++++++++++++++++++++++++++++++++
 4 files changed, 119 insertions(+)
 create mode 100644 drivers/irqchip/irq-rda-intc.c

diff --git a/arch/arm/mach-rda/Kconfig b/arch/arm/mach-rda/Kconfig
index dafab78d7aab..29012bc68ca4 100644
--- a/arch/arm/mach-rda/Kconfig
+++ b/arch/arm/mach-rda/Kconfig

@@ -3,5 +3,6 @@ menuconfig ARCH_RDA
 	depends on ARCH_MULTI_V7
 	select COMMON_CLK
 	select GENERIC_IRQ_CHIP
+	select RDA_INTC
 	help
 	  This enables support for the RDA Micro 8810PL SoC family.

diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index 51a5ef0e96ed..9d54645870ad 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig

@@ -195,6 +195,10 @@ config JCORE_AIC
 	help
 	  Support for the J-Core integrated AIC.
 
+config RDA_INTC
+	bool
+	select IRQ_DOMAIN
+
 config RENESAS_INTC_IRQPIN
 	bool
 	select IRQ_DOMAIN

diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
index 794c13d3ac3d..417108027e40 100644
--- a/drivers/irqchip/Makefile
+++ b/drivers/irqchip/Makefile

@@ -43,6 +43,7 @@ obj-$(CONFIG_IMGPDC_IRQ)		+= irq-imgpdc.o
 obj-$(CONFIG_IRQ_MIPS_CPU)		+= irq-mips-cpu.o
 obj-$(CONFIG_SIRF_IRQ)			+= irq-sirfsoc.o
 obj-$(CONFIG_JCORE_AIC)			+= irq-jcore-aic.o
+obj-$(CONFIG_RDA_INTC)			+= irq-rda-intc.o
 obj-$(CONFIG_RENESAS_INTC_IRQPIN)	+= irq-renesas-intc-irqpin.o
 obj-$(CONFIG_RENESAS_IRQC)		+= irq-renesas-irqc.o
 obj-$(CONFIG_VERSATILE_FPGA_IRQ)	+= irq-versatile-fpga.o

diff --git a/drivers/irqchip/irq-rda-intc.c b/drivers/irqchip/irq-rda-intc.c
new file mode 100644
index 000000000000..1b372bdb23bc
--- /dev/null
+++ b/drivers/irqchip/irq-rda-intc.c

@@ -0,0 +1,113 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * RDA8810PL SoC irqchip driver
+ *
+ * Copyright RDA Microelectronics Company Limited
+ * Copyright (c) 2017 Andreas F?rber
+ * Copyright (c) 2018 Manivannan Sadhasivam
+ */
+
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/irqchip.h>
+#include <linux/irqdomain.h>
+#include <linux/of_address.h>
+
+#include <asm/irq.h>

You shouldn't need to include this.

Ack.

quoted

+#include <asm/exception.h>
+
+#define RDA_INTC_FINALSTATUS	0x00
+#define RDA_INTC_STATUS		0x04
+#define RDA_INTC_MASK_SET	0x08
+#define RDA_INTC_MASK_CLR	0x0c
+#define RDA_INTC_WAKEUP_MASK	0x18
+#define RDA_INTC_CPU_SLEEP	0x1c

Half of these constants are unused. Do we really need them?

Usually I tend to define all registers to provide overall reg map. But
I have no issues to remove the not used ones.

quoted

+
+#define RDA_IRQ_MASK_ALL	0xFFFFFFFF
+
+#define RDA_NR_IRQS 32

Surely the mask can be derived from the number of interrupts?

Why not? Since each bit corresponds to a single interrupt, 0xFFFFFFFF
can cover all 32 bits which is equal to the total number of interrupts
supported by the controller. Am I missing anything here?

quoted

+
+static void __iomem *base;

Everything in this driver is prefixed with rda_. It would seem valuable
to  do the same here, as "base" is a bit too generic.

Ack.

quoted

+
+static void rda_intc_mask_irq(struct irq_data *d)
+{
+	writel_relaxed(BIT(d->hwirq), base + RDA_INTC_MASK_CLR);
+}
+
+static void rda_intc_unmask_irq(struct irq_data *d)
+{
+	writel_relaxed(BIT(d->hwirq), base + RDA_INTC_MASK_SET);

Are the names MASK_CLR and MASK_SET from the datasheet? They seem to be
backward (you set the mask to unmask...), and seem to behave like an
enable instead. That's not a big issue, just curious.

Yes, this naming convention comes from the datasheet and it is a bit
wierd as you said ;-)

quoted

+}
+
+static int rda_intc_set_type(struct irq_data *data, unsigned int flow_type)
+{
+	/* Hardware supports only level triggered interrupts */
+	if (flow_type & (IRQF_TRIGGER_HIGH | IRQF_TRIGGER_LOW))
+		irq_set_handler(data->irq, handle_level_irq);

Why do you need to do this? You've already configured it at map time,
and it is not changing under your feet. This should be written as:

if ((flow_type & (IRQF_TRIGGER_HIGH | IRQF_TRIGGER_LOW)) == flow_type)
	return 0;

return -EINVAL;

Okay.

quoted

+	else
+		return -EINVAL;
+
+	return 0;
+}
+
+static struct irq_domain *rda_irq_domain;

Please move this to the top of the file, next to "base".

Ack.

quoted

+
+static void __exception_irq_entry rda_handle_irq(struct pt_regs *regs)
+{
+	u32 stat = readl_relaxed(base + RDA_INTC_FINALSTATUS);
+	u32 hwirq;
+
+	while (stat) {
+		hwirq = __fls(stat);
+		handle_domain_irq(rda_irq_domain, hwirq, regs);
+		stat &= ~(1 << hwirq);
+	}
+}
+
+static struct irq_chip rda_irq_chip = {
+	.name		= "rda-intc",
+	.irq_mask	= rda_intc_mask_irq,
+	.irq_unmask	= rda_intc_unmask_irq,
+	.irq_set_type	= rda_intc_set_type,
+};
+
+static int rda_irq_map(struct irq_domain *d,
+		       unsigned int virq, irq_hw_number_t hw)
+{
+	irq_set_status_flags(virq, IRQ_LEVEL);
+	irq_set_chip_and_handler(virq, &rda_irq_chip, handle_level_irq);
+	irq_set_chip_data(virq, d->host_data);
+	irq_set_probe(virq);
+
+	return 0;
+}
+
+static const struct irq_domain_ops rda_irq_domain_ops = {
+	.map = rda_irq_map,
+	.xlate = irq_domain_xlate_onecell,
+};
+
+static int __init rda8810_intc_init(struct device_node *node,
+				    struct device_node *parent)
+{
+	base = of_io_request_and_map(node, 0, "rda-intc");
+	if (!base)
+		return -ENXIO;
+
+	/* Mask, and invalidate all interrupt sources */

What does "invalidate" mean here?

Mean to say "disable" but yeah not appropriate. Will remove it.

quoted

+	writel_relaxed(RDA_IRQ_MASK_ALL, base + RDA_INTC_MASK_CLR);
+
+	rda_irq_domain = irq_domain_create_linear(&node->fwnode, RDA_NR_IRQS,
+						  &rda_irq_domain_ops, base);
+	if (WARN_ON(!rda_irq_domain)) {
+		iounmap(base);
+		return -ENODEV;

Why ENODEV? ENOMEM seems more appropriate. The WARN_ON is a bit
superfluous, as the failing probe should be noisy enough.

Ack. ENOMEM comes from your suggestion in previous review.

quoted

+	}
+
+	set_handle_irq(rda_handle_irq);
+
+	return 0;
+}
+
+IRQCHIP_DECLARE(rda_intc, "rda,8810pl-intc", rda8810_intc_init);

You've already posted two versions in 3 days, please allow for a week
between versions.

Sorry for that. I thought the other way, allowing too much delay would
hinder the review process. Will post the next revision after few more days.

Thanks,
Mani

Thanks,

	M.
-- 
Jazz is not dead. It just smells funny...