On Tue, Aug 24, 2021 at 1:05 PM Rob Herring <robh+dt@xxxxxxxxxx> wrote:
>
> +Saravana
>
> Saravana mentioned to me there may be some issues with this one...
>
>
> On Mon, Aug 16, 2021 at 2:43 AM Kefeng Wang <wangkefeng.wang@xxxxxxxxxx> wrote:
> >
> > of_amba_device_create() uses irq_of_parse_and_map() to translate
> > a DT interrupt specification into a Linux virtual interrupt number.
> >
> > But it doesn't properly handle the case where the interrupt controller
> > is not yet available, eg, when pl011 interrupt is connected to MBIGEN
> > interrupt controller, because the mbigen initialization is too late,
> > which will lead to no IRQ due to no IRQ domain found, log is shown below,
> > "irq: no irq domain found for uart0 !"
> >
> > use of_irq_get() to return -EPROBE_DEFER as above, and in the function
> > amba_device_try_add()/amba_device_add(), it will properly handle in such
> > case, also return 0 in other fail cases to be consistent as before.
> >
> > Cc: Russell King <linux@xxxxxxxxxxxxxxx>
> > Cc: Rob Herring <robh+dt@xxxxxxxxxx>
> > Cc: Frank Rowand <frowand.list@xxxxxxxxx>
> > Reported-by: Ruizhe Lin <linruizhe@xxxxxxxxxx>
> > Signed-off-by: Kefeng Wang <wangkefeng.wang@xxxxxxxxxx>
> > ---
> > drivers/amba/bus.c | 27 +++++++++++++++++++++++++++
> > drivers/of/platform.c | 6 +-----
> > 2 files changed, 28 insertions(+), 5 deletions(-)
> >
> > diff --git a/drivers/amba/bus.c b/drivers/amba/bus.c
> > index 36f2f42c8014..720aa6cdd402 100644
> > --- a/drivers/amba/bus.c
> > +++ b/drivers/amba/bus.c
> > @@ -19,6 +19,7 @@
> > #include <linux/clk/clk-conf.h>
> > #include <linux/platform_device.h>
> > #include <linux/reset.h>
> > +#include <linux/of_irq.h>
> >
> > #include <asm/irq.h>
> >
> > @@ -371,12 +372,38 @@ static void amba_device_release(struct device *dev)
> > kfree(d);
> > }
> >
> > +static int of_amba_device_decode_irq(struct amba_device *dev)
> > +{
> > + struct device_node *node = dev->dev.of_node;
> > + int i, irq = 0;
> > +
> > + if (IS_ENABLED(CONFIG_OF_IRQ) && node) {
> > + /* Decode the IRQs and address ranges */
> > + for (i = 0; i < AMBA_NR_IRQS; i++) {
> > + irq = of_irq_get(node, i);
> > + if (irq < 0) {
> > + if (irq == -EPROBE_DEFER)
> > + return irq;
> > + irq = 0;
> > + }
> > +
> > + dev->irq[i] = irq;
> > + }
> > + }
> > +
> > + return 0;
> > +}
> > +
> > static int amba_device_try_add(struct amba_device *dev, struct resource *parent)
> > {
> > u32 size;
> > void __iomem *tmp;
> > int i, ret;
> >
> > + ret = of_amba_device_decode_irq(dev);
> > + if (ret)
> > + goto err_out;
> > +
Similar to other resources the AMBA bus "gets" for the device, I think
this should be moved into amba_probe() and not here. There's no reason
to delay the addition of the device (and loading its module) because
the IRQ isn't ready yet.
-Saravana
> > ret = request_resource(parent, &dev->res);
> > if (ret)
> > goto err_out;
> > diff --git a/drivers/of/platform.c b/drivers/of/platform.c
> > index 74afbb7a4f5e..32d5ff8df747 100644
> > --- a/drivers/of/platform.c
> > +++ b/drivers/of/platform.c
> > @@ -222,7 +222,7 @@ static struct amba_device *of_amba_device_create(struct device_node *node,
> > {
> > struct amba_device *dev;
> > const void *prop;
> > - int i, ret;
> > + int ret;
> >
> > pr_debug("Creating amba device %pOF\n", node);
> >
> > @@ -253,10 +253,6 @@ static struct amba_device *of_amba_device_create(struct device_node *node,
> > if (prop)
> > dev->periphid = of_read_ulong(prop, 1);
> >
> > - /* Decode the IRQs and address ranges */
> > - for (i = 0; i < AMBA_NR_IRQS; i++)
> > - dev->irq[i] = irq_of_parse_and_map(node, i);
> > -
> > ret = of_address_to_resource(node, 0, &dev->res);
> > if (ret) {
> > pr_err("amba: of_address_to_resource() failed (%d) for %pOF\n",
> > --
> > 2.26.2
> >
