2020-02-11 21:38:15

by Mubin Usman Sayyed

[permalink] [raw]
Subject: [PATCH v3] irqchip: xilinx: Add support for multiple instances

From: Mubin Sayyed <[email protected]>

This patch adds support for multiple instances of
xilinx interrupt controller. Below configurations are
supported by driver,

- peripheral->xilinx-intc->xilinx-intc->gic
- peripheral->xilinx-intc->xilinx-intc

Signed-off-by: Anirudha Sarangi <[email protected]>
Signed-off-by: Mubin Sayyed <[email protected]>
---
Changes for v3:
- Modified prototype of xintc_write/xintc_read
- Fixed review comments regarding indentation/variable
names, used BIT
- Modified xintc_get_irq_local to return 0
in case of failure/no pending interrupts
- Fixed return type of xintc_read
- Reverted changes related to device name and
kept intc_dev as static

Changes for v2:
- Removed write_fn/read_fn hooks, used xintc_write/
xintc_read directly
- Moved primary_intc declaration after xintc_irq_chip
---
drivers/irqchip/irq-xilinx-intc.c | 115 ++++++++++++++++++------------
1 file changed, 68 insertions(+), 47 deletions(-)

diff --git a/drivers/irqchip/irq-xilinx-intc.c b/drivers/irqchip/irq-xilinx-intc.c
index e3043ded8973..51f461d2934f 100644
--- a/drivers/irqchip/irq-xilinx-intc.c
+++ b/drivers/irqchip/irq-xilinx-intc.c
@@ -38,29 +38,32 @@ struct xintc_irq_chip {
void __iomem *base;
struct irq_domain *root_domain;
u32 intr_mask;
+ struct irq_chip *intc_dev;
+ u32 nr_irq;
};

-static struct xintc_irq_chip *xintc_irqc;
+static struct xintc_irq_chip *primary_intc;

-static void xintc_write(int reg, u32 data)
+static void xintc_write(struct xintc_irq_chip *irqc, int reg, u32 data)
{
if (static_branch_unlikely(&xintc_is_be))
- iowrite32be(data, xintc_irqc->base + reg);
+ iowrite32be(data, irqc->base + reg);
else
- iowrite32(data, xintc_irqc->base + reg);
+ iowrite32(data, irqc->base + reg);
}

-static unsigned int xintc_read(int reg)
+static u32 xintc_read(struct xintc_irq_chip *irqc, int reg)
{
if (static_branch_unlikely(&xintc_is_be))
- return ioread32be(xintc_irqc->base + reg);
+ return ioread32be(irqc->base + reg);
else
- return ioread32(xintc_irqc->base + reg);
+ return ioread32(irqc->base + reg);
}

static void intc_enable_or_unmask(struct irq_data *d)
{
- unsigned long mask = 1 << d->hwirq;
+ unsigned long mask = BIT(d->hwirq);
+ struct xintc_irq_chip *irqc = irq_data_get_irq_chip_data(d);

pr_debug("irq-xilinx: enable_or_unmask: %ld\n", d->hwirq);

@@ -69,30 +72,35 @@ static void intc_enable_or_unmask(struct irq_data *d)
* acks the irq before calling the interrupt handler
*/
if (irqd_is_level_type(d))
- xintc_write(IAR, mask);
+ xintc_write(irqc, IAR, mask);

- xintc_write(SIE, mask);
+ xintc_write(irqc, SIE, mask);
}

static void intc_disable_or_mask(struct irq_data *d)
{
+ struct xintc_irq_chip *irqc = irq_data_get_irq_chip_data(d);
+
pr_debug("irq-xilinx: disable: %ld\n", d->hwirq);
- xintc_write(CIE, 1 << d->hwirq);
+ xintc_write(irqc, CIE, BIT(d->hwirq));
}

static void intc_ack(struct irq_data *d)
{
+ struct xintc_irq_chip *irqc = irq_data_get_irq_chip_data(d);
+
pr_debug("irq-xilinx: ack: %ld\n", d->hwirq);
- xintc_write(IAR, 1 << d->hwirq);
+ xintc_write(irqc, IAR, BIT(d->hwirq));
}

static void intc_mask_ack(struct irq_data *d)
{
- unsigned long mask = 1 << d->hwirq;
+ unsigned long mask = BIT(d->hwirq);
+ struct xintc_irq_chip *irqc = irq_data_get_irq_chip_data(d);

pr_debug("irq-xilinx: disable_and_ack: %ld\n", d->hwirq);
- xintc_write(CIE, mask);
- xintc_write(IAR, mask);
+ xintc_write(irqc, CIE, mask);
+ xintc_write(irqc, IAR, mask);
}

static struct irq_chip intc_dev = {
@@ -103,13 +111,28 @@ static struct irq_chip intc_dev = {
.irq_mask_ack = intc_mask_ack,
};

+static unsigned int xintc_get_irq_local(struct xintc_irq_chip *irqc)
+{
+ u32 hwirq;
+ unsigned int irq = 0;
+
+ hwirq = xintc_read(irqc, IVR);
+ if (hwirq != -1U)
+ irq = irq_find_mapping(irqc->root_domain, hwirq);
+
+ pr_debug("irq-xilinx: hwirq=%d, irq=%d\n", hwirq, irq);
+
+ return irq;
+}
+
unsigned int xintc_get_irq(void)
{
- unsigned int hwirq, irq = -1;
+ u32 hwirq;
+ unsigned int irq = -1;

- hwirq = xintc_read(IVR);
+ hwirq = xintc_read(primary_intc, IVR);
if (hwirq != -1U)
- irq = irq_find_mapping(xintc_irqc->root_domain, hwirq);
+ irq = irq_find_mapping(primary_intc->root_domain, hwirq);

pr_debug("irq-xilinx: hwirq=%d, irq=%d\n", hwirq, irq);

@@ -118,15 +141,18 @@ unsigned int xintc_get_irq(void)

static int xintc_map(struct irq_domain *d, unsigned int irq, irq_hw_number_t hw)
{
- if (xintc_irqc->intr_mask & (1 << hw)) {
- irq_set_chip_and_handler_name(irq, &intc_dev,
+ struct xintc_irq_chip *irqc = d->host_data;
+
+ if (irqc->intr_mask & BIT(hw)) {
+ irq_set_chip_and_handler_name(irq, irqc->intc_dev,
handle_edge_irq, "edge");
irq_clear_status_flags(irq, IRQ_LEVEL);
} else {
- irq_set_chip_and_handler_name(irq, &intc_dev,
+ irq_set_chip_and_handler_name(irq, irqc->intc_dev,
handle_level_irq, "level");
irq_set_status_flags(irq, IRQ_LEVEL);
}
+ irq_set_chip_data(irq, irqc);
return 0;
}

@@ -138,12 +164,14 @@ static const struct irq_domain_ops xintc_irq_domain_ops = {
static void xil_intc_irq_handler(struct irq_desc *desc)
{
struct irq_chip *chip = irq_desc_get_chip(desc);
+ struct xintc_irq_chip *irqc =
+ irq_data_get_irq_handler_data(&desc->irq_data);
u32 pending;

chained_irq_enter(chip, desc);
do {
- pending = xintc_get_irq();
- if (pending == -1U)
+ pending = xintc_get_irq_local(irqc);
+ if (pending == 0U)
break;
generic_handle_irq(pending);
} while (true);
@@ -153,28 +181,19 @@ static void xil_intc_irq_handler(struct irq_desc *desc)
static int __init xilinx_intc_of_init(struct device_node *intc,
struct device_node *parent)
{
- u32 nr_irq;
int ret, irq;
struct xintc_irq_chip *irqc;

- if (xintc_irqc) {
- pr_err("irq-xilinx: Multiple instances aren't supported\n");
- return -EINVAL;
- }
-
irqc = kzalloc(sizeof(*irqc), GFP_KERNEL);
if (!irqc)
return -ENOMEM;
-
- xintc_irqc = irqc;
-
irqc->base = of_iomap(intc, 0);
BUG_ON(!irqc->base);

- ret = of_property_read_u32(intc, "xlnx,num-intr-inputs", &nr_irq);
+ ret = of_property_read_u32(intc, "xlnx,num-intr-inputs", &irqc->nr_irq);
if (ret < 0) {
pr_err("irq-xilinx: unable to read xlnx,num-intr-inputs\n");
- goto err_alloc;
+ goto error;
}

ret = of_property_read_u32(intc, "xlnx,kind-of-intr", &irqc->intr_mask);
@@ -183,34 +202,35 @@ static int __init xilinx_intc_of_init(struct device_node *intc,
irqc->intr_mask = 0;
}

- if (irqc->intr_mask >> nr_irq)
+ if (irqc->intr_mask >> irqc->nr_irq)
pr_warn("irq-xilinx: mismatch in kind-of-intr param\n");

pr_info("irq-xilinx: %pOF: num_irq=%d, edge=0x%x\n",
- intc, nr_irq, irqc->intr_mask);
+ intc, irqc->nr_irq, irqc->intr_mask);

+ irqc->intc_dev = &intc_dev;

/*
* Disable all external interrupts until they are
* explicity requested.
*/
- xintc_write(IER, 0);
+ xintc_write(irqc, IER, 0);

/* Acknowledge any pending interrupts just in case. */
- xintc_write(IAR, 0xffffffff);
+ xintc_write(irqc, IAR, 0xffffffff);

/* Turn on the Master Enable. */
- xintc_write(MER, MER_HIE | MER_ME);
- if (!(xintc_read(MER) & (MER_HIE | MER_ME))) {
+ xintc_write(irqc, MER, MER_HIE | MER_ME);
+ if (!(xintc_read(irqc, MER) & (MER_HIE | MER_ME))) {
static_branch_enable(&xintc_is_be);
- xintc_write(MER, MER_HIE | MER_ME);
+ xintc_write(irqc, MER, MER_HIE | MER_ME);
}

- irqc->root_domain = irq_domain_add_linear(intc, nr_irq,
+ irqc->root_domain = irq_domain_add_linear(intc, irqc->nr_irq,
&xintc_irq_domain_ops, irqc);
if (!irqc->root_domain) {
pr_err("irq-xilinx: Unable to create IRQ domain\n");
- goto err_alloc;
+ goto error;
}

if (parent) {
@@ -222,16 +242,17 @@ static int __init xilinx_intc_of_init(struct device_node *intc,
} else {
pr_err("irq-xilinx: interrupts property not in DT\n");
ret = -EINVAL;
- goto err_alloc;
+ goto error;
}
} else {
- irq_set_default_host(irqc->root_domain);
+ primary_intc = irqc;
+ irq_set_default_host(primary_intc->root_domain);
}

return 0;

-err_alloc:
- xintc_irqc = NULL;
+error:
+ iounmap(irqc->base);
kfree(irqc);
return ret;

--
2.25.0


2020-02-13 12:02:12

by Thomas Gleixner

[permalink] [raw]
Subject: Re: [PATCH v3] irqchip: xilinx: Add support for multiple instances

Mubin,

Mubin Usman Sayyed <[email protected]> writes:

> From: Mubin Sayyed <[email protected]>
>
> This patch adds support for multiple instances of

git grep 'This patch' Documentation/process/submitting-patches.rst

> xilinx interrupt controller. Below configurations are
> supported by driver,
>
> - peripheral->xilinx-intc->xilinx-intc->gic
> - peripheral->xilinx-intc->xilinx-intc

This is really not much of an explanation.

> Signed-off-by: Anirudha Sarangi <[email protected]>
> Signed-off-by: Mubin Sayyed <[email protected]>

This Signed-off-by chain is incorrect. See chapter 11 and 12 in the same
document.

> @@ -38,29 +38,32 @@ struct xintc_irq_chip {
> void __iomem *base;
> struct irq_domain *root_domain;
> u32 intr_mask;
> + struct irq_chip *intc_dev;
> + u32 nr_irq;
> };
>
> -static struct xintc_irq_chip *xintc_irqc;
> +static struct xintc_irq_chip *primary_intc;
>
> -static void xintc_write(int reg, u32 data)
> +static void xintc_write(struct xintc_irq_chip *irqc, int reg, u32 data)
> {
> if (static_branch_unlikely(&xintc_is_be))
> - iowrite32be(data, xintc_irqc->base + reg);
> + iowrite32be(data, irqc->base + reg);
> else
> - iowrite32(data, xintc_irqc->base + reg);
> + iowrite32(data, irqc->base + reg);
> }
>
> -static unsigned int xintc_read(int reg)
> +static u32 xintc_read(struct xintc_irq_chip *irqc, int reg)
> {
> if (static_branch_unlikely(&xintc_is_be))
> - return ioread32be(xintc_irqc->base + reg);
> + return ioread32be(irqc->base + reg);
> else
> - return ioread32(xintc_irqc->base + reg);
> + return ioread32(irqc->base + reg);
> }
>
> static void intc_enable_or_unmask(struct irq_data *d)
> {
> - unsigned long mask = 1 << d->hwirq;
> + unsigned long mask = BIT(d->hwirq);
> + struct xintc_irq_chip *irqc = irq_data_get_irq_chip_data(d);

Please order your local variables in reverse fir tree order:

struct xintc_irq_chip *irqc = irq_data_get_irq_chip_data(d);
unsigned long mask = BIT(d->hwirq);

which is the preferred coding style in this subsystem and way simpler to
read.

> static void intc_mask_ack(struct irq_data *d)
> {
> - unsigned long mask = 1 << d->hwirq;
> + unsigned long mask = BIT(d->hwirq);
> + struct xintc_irq_chip *irqc = irq_data_get_irq_chip_data(d);

Ditto.

> pr_debug("irq-xilinx: disable_and_ack: %ld\n", d->hwirq);
> - xintc_write(CIE, mask);
> - xintc_write(IAR, mask);
> + xintc_write(irqc, CIE, mask);
> + xintc_write(irqc, IAR, mask);
> }
> +static unsigned int xintc_get_irq_local(struct xintc_irq_chip *irqc)
> +{
> + u32 hwirq;
> + unsigned int irq = 0;

Same.

> + hwirq = xintc_read(irqc, IVR);
> + if (hwirq != -1U)
> + irq = irq_find_mapping(irqc->root_domain, hwirq);
> +
> + pr_debug("irq-xilinx: hwirq=%d, irq=%d\n", hwirq, irq);

Are these pr_debugs all over the please really required? I can
understand that you use them for development, but are they useful once
the stuff works?

> + return irq;
> +}
> +
> unsigned int xintc_get_irq(void)
> {
> - unsigned int hwirq, irq = -1;
> + u32 hwirq;
> + unsigned int irq = -1;

See above.

> - hwirq = xintc_read(IVR);
> + hwirq = xintc_read(primary_intc, IVR);
> if (hwirq != -1U)
> - irq = irq_find_mapping(xintc_irqc->root_domain, hwirq);
> + irq = irq_find_mapping(primary_intc->root_domain, hwirq);
>
> pr_debug("irq-xilinx: hwirq=%d, irq=%d\n", hwirq, irq);
>
> @@ -138,12 +164,14 @@ static const struct irq_domain_ops xintc_irq_domain_ops = {
> static void xil_intc_irq_handler(struct irq_desc *desc)
> {
> struct irq_chip *chip = irq_desc_get_chip(desc);
> + struct xintc_irq_chip *irqc =
> + irq_data_get_irq_handler_data(&desc->irq_data);

Please avoid these ugly line breaks and put the initialization of the
variable in to the code below the declaration.

> /* Turn on the Master Enable. */
> - xintc_write(MER, MER_HIE | MER_ME);
> - if (!(xintc_read(MER) & (MER_HIE | MER_ME))) {
> + xintc_write(irqc, MER, MER_HIE | MER_ME);
> + if (!(xintc_read(irqc, MER) & (MER_HIE | MER_ME))) {
> static_branch_enable(&xintc_is_be);

I see it's existing logic, but this lacks a comment how it's determined
that xintc is big endian. Looks like some weird "write works?"
probing. Why?

> + xintc_write(irqc, MER, MER_HIE | MER_ME);

So this writes MER_HIE | MER_ME into MER

> + if (!(xintc_read(irqc, MER) & (MER_HIE | MER_ME))) {

but this checks just whether ONE of the bits is set. Shouldn't it check
for MER == (MER_HIE | MER_ME), i.e. read back what was written?

Thanks,

tglx

2020-02-14 21:11:01

by Mubin Usman Sayyed

[permalink] [raw]
Subject: RE: [PATCH v3] irqchip: xilinx: Add support for multiple instances

Hi Thomas,

Thanks for the review. Please see my inline replies.

> -----Original Message-----
> From: Thomas Gleixner <[email protected]>
> Sent: Thursday, February 13, 2020 5:31 PM
> To: Mubin Usman Sayyed <[email protected]>;
> [email protected]; [email protected]; Michal Simek
> <[email protected]>; [email protected]
> Cc: [email protected]; Siva Durga Prasad Paladugu
> <[email protected]>; Anirudha Sarangi <[email protected]>; Mubin
> Usman Sayyed <[email protected]>
> Subject: Re: [PATCH v3] irqchip: xilinx: Add support for multiple instances
>
> Mubin,
>
> Mubin Usman Sayyed <[email protected]> writes:
>
> > From: Mubin Sayyed <[email protected]>
> >
> > This patch adds support for multiple instances of
>
> git grep 'This patch' Documentation/process/submitting-patches.rst
[Mubin]: I will re-phrase it in next version.
>
> > xilinx interrupt controller. Below configurations are supported by
> > driver,
> >
> > - peripheral->xilinx-intc->xilinx-intc->gic
> > - peripheral->xilinx-intc->xilinx-intc
>
> This is really not much of an explanation.
[Mubin]: Will elaborate in next version
>
> > Signed-off-by: Anirudha Sarangi <[email protected]>
> > Signed-off-by: Mubin Sayyed <[email protected]>
>
> This Signed-off-by chain is incorrect. See chapter 11 and 12 in the same
> document.
[Mubin]: Sure, I will check and fix it. I ran checkpatch, it didn't reported errors/warning related to that.
>
> > @@ -38,29 +38,32 @@ struct xintc_irq_chip {
> > void __iomem *base;
> > struct irq_domain *root_domain;
> > u32 intr_mask;
> > + struct irq_chip *intc_dev;
> > + u32 nr_irq;
> > };
> >
> > -static struct xintc_irq_chip *xintc_irqc;
> > +static struct xintc_irq_chip *primary_intc;
> >
> > -static void xintc_write(int reg, u32 data)
> > +static void xintc_write(struct xintc_irq_chip *irqc, int reg, u32
> > +data)
> > {
> > if (static_branch_unlikely(&xintc_is_be))
> > - iowrite32be(data, xintc_irqc->base + reg);
> > + iowrite32be(data, irqc->base + reg);
> > else
> > - iowrite32(data, xintc_irqc->base + reg);
> > + iowrite32(data, irqc->base + reg);
> > }
> >
> > -static unsigned int xintc_read(int reg)
> > +static u32 xintc_read(struct xintc_irq_chip *irqc, int reg)
> > {
> > if (static_branch_unlikely(&xintc_is_be))
> > - return ioread32be(xintc_irqc->base + reg);
> > + return ioread32be(irqc->base + reg);
> > else
> > - return ioread32(xintc_irqc->base + reg);
> > + return ioread32(irqc->base + reg);
> > }
> >
> > static void intc_enable_or_unmask(struct irq_data *d) {
> > - unsigned long mask = 1 << d->hwirq;
> > + unsigned long mask = BIT(d->hwirq);
> > + struct xintc_irq_chip *irqc = irq_data_get_irq_chip_data(d);
>
> Please order your local variables in reverse fir tree order:
>
> struct xintc_irq_chip *irqc = irq_data_get_irq_chip_data(d);
> unsigned long mask = BIT(d->hwirq);
>
> which is the preferred coding style in this subsystem and way simpler to
> read.
[Mubin]: I will fix all such instances in next version
>
> > static void intc_mask_ack(struct irq_data *d) {
> > - unsigned long mask = 1 << d->hwirq;
> > + unsigned long mask = BIT(d->hwirq);
> > + struct xintc_irq_chip *irqc = irq_data_get_irq_chip_data(d);
>
> Ditto.
>
> > pr_debug("irq-xilinx: disable_and_ack: %ld\n", d->hwirq);
> > - xintc_write(CIE, mask);
> > - xintc_write(IAR, mask);
> > + xintc_write(irqc, CIE, mask);
> > + xintc_write(irqc, IAR, mask);
> > }
> > +static unsigned int xintc_get_irq_local(struct xintc_irq_chip *irqc)
> > +{
> > + u32 hwirq;
> > + unsigned int irq = 0;
>
> Same.
>
> > + hwirq = xintc_read(irqc, IVR);
> > + if (hwirq != -1U)
> > + irq = irq_find_mapping(irqc->root_domain, hwirq);
> > +
> > + pr_debug("irq-xilinx: hwirq=%d, irq=%d\n", hwirq, irq);
>
> Are these pr_debugs all over the please really required? I can understand
> that you use them for development, but are they useful once the stuff
> works?
[Mubin] They might be useful to debug interrupt issues. Do you want me to remove them?
>
> > + return irq;
> > +}
> > +
> > unsigned int xintc_get_irq(void)
> > {
> > - unsigned int hwirq, irq = -1;
> > + u32 hwirq;
> > + unsigned int irq = -1;
>
> See above.
>
> > - hwirq = xintc_read(IVR);
> > + hwirq = xintc_read(primary_intc, IVR);
> > if (hwirq != -1U)
> > - irq = irq_find_mapping(xintc_irqc->root_domain, hwirq);
> > + irq = irq_find_mapping(primary_intc->root_domain, hwirq);
> >
> > pr_debug("irq-xilinx: hwirq=%d, irq=%d\n", hwirq, irq);
> >
> > @@ -138,12 +164,14 @@ static const struct irq_domain_ops
> > xintc_irq_domain_ops = { static void xil_intc_irq_handler(struct
> > irq_desc *desc) {
> > struct irq_chip *chip = irq_desc_get_chip(desc);
> > + struct xintc_irq_chip *irqc =
> > + irq_data_get_irq_handler_data(&desc->irq_data);
>
> Please avoid these ugly line breaks and put the initialization of the variable in
> to the code below the declaration.
[Mubin]: Will do in next version
>
> > /* Turn on the Master Enable. */
> > - xintc_write(MER, MER_HIE | MER_ME);
> > - if (!(xintc_read(MER) & (MER_HIE | MER_ME))) {
> > + xintc_write(irqc, MER, MER_HIE | MER_ME);
> > + if (!(xintc_read(irqc, MER) & (MER_HIE | MER_ME))) {
> > static_branch_enable(&xintc_is_be);
>
> I see it's existing logic, but this lacks a comment how it's determined that
> xintc is big endian. Looks like some weird "write works?"
> probing. Why?
>
> > + xintc_write(irqc, MER, MER_HIE | MER_ME);
>
> So this writes MER_HIE | MER_ME into MER
>
> > + if (!(xintc_read(irqc, MER) & (MER_HIE | MER_ME))) {
>
> but this checks just whether ONE of the bits is set. Shouldn't it check for MER
> == (MER_HIE | MER_ME), i.e. read back what was written?

[Mubin]: Agreed, will fix it in v4.

Thanks,
Mubin
>
> Thanks,
>
> tglx