On Fri, Jun 13, 2014 at 12:07:49PM +0530, Sricharan R wrote: > Hi Jason, > > On Thursday 12 June 2014 07:37 PM, Jason Cooper wrote: > > On Thu, Jun 12, 2014 at 06:49:17PM +0530, Sricharan R wrote: > >> Hi Jason, > >> > >> On Thursday 12 June 2014 06:21 PM, Jason Cooper wrote: > >>> On Thu, Jun 12, 2014 at 05:23:11PM +0530, Sricharan R wrote: > >>>> From: Nishanth Menon <nm@xxxxxx> > >>>> > >>>> When, in the system due to varied reasons, interrupts might be unusable > >>>> due to hardware behavior, but register maps do exist, then those interrupts > >>>> should be skipped while mapping irq to crossbars. > >>>> > >>>> Signed-off-by: Nishanth Menon <nm@xxxxxx> > >>>> Signed-off-by: Sricharan R <r.sricharan@xxxxxx> > >>>> Signed-off-by: Tony Lindgren <tony@xxxxxxxxxxx> > >>> > >>> Tony, have you applied these somewhere already? > >>> > >>>> --- > >>>> drivers/irqchip/irq-crossbar.c | 47 ++++++++++++++++++++++++++++++++++++---- > >>>> 1 file changed, 43 insertions(+), 4 deletions(-) > >>>> > >>>> diff --git a/drivers/irqchip/irq-crossbar.c b/drivers/irqchip/irq-crossbar.c > >>>> index 51d4b87..847f6e3 100644 > >>>> --- a/drivers/irqchip/irq-crossbar.c > >>>> +++ b/drivers/irqchip/irq-crossbar.c > >>>> @@ -13,11 +13,13 @@ > >>>> #include <linux/io.h> > >>>> #include <linux/of_address.h> > >>>> #include <linux/of_irq.h> > >>>> +#include <linux/of_device.h> > >>>> #include <linux/slab.h> > >>>> #include <linux/irqchip/arm-gic.h> > >>>> > >>>> #define IRQ_FREE -1 > >>>> #define IRQ_RESERVED -2 > >>>> +#define IRQ_SKIP -3 > >>>> #define GIC_IRQ_START 32 > >>>> > >>>> /* > >>>> @@ -34,6 +36,16 @@ struct crossbar_device { > >>>> void (*write) (int, int); > >>>> }; > >>>> > >>>> +/** > >>>> + * struct crossbar_data: Platform specific data > >>>> + * @irqs_unused: array of irqs that cannot be used because of hw erratas > >>>> + * @size: size of the irqs_unused array > >>>> + */ > >>>> +struct crossbar_data { > >>>> + const uint *irqs_unused; > >>>> + const uint size; > >>>> +}; > >>>> + > >>>> static struct crossbar_device *cb; > >>>> > >>>> static inline void crossbar_writel(int irq_no, int cb_no) > >>>> @@ -119,10 +131,12 @@ const struct irq_domain_ops routable_irq_domain_ops = { > >>>> .xlate = crossbar_domain_xlate > >>>> }; > >>>> > >>>> -static int __init crossbar_of_init(struct device_node *node) > >>>> +static int __init crossbar_of_init(struct device_node *node, > >>>> + const struct crossbar_data *data) > >>>> { > >>>> int i, size, max, reserved = 0, entry; > >>>> const __be32 *irqsr; > >>>> + const int *irqsk = NULL; > >>>> > >>>> cb = kzalloc(sizeof(*cb), GFP_KERNEL); > >>>> > >>>> @@ -194,6 +208,22 @@ static int __init crossbar_of_init(struct device_node *node) > >>>> reserved += size; > >>>> } > >>>> > >>>> + /* Skip the ones marked as unused */ > >>>> + if (data) { > >>>> + irqsk = data->irqs_unused; > >>>> + size = data->size; > >>>> + > >>>> + for (i = 0; i < size; i++) { > >>>> + entry = irqsk[i]; > >>>> + > >>>> + if (entry > max) { > >>>> + pr_err("Invalid skip entry\n"); > >>>> + goto err3; > >>>> + } > >>>> + cb->irq_map[entry] = IRQ_SKIP; > >>>> + } > >>>> + } > >>>> + > >>>> register_routable_domain_ops(&routable_irq_domain_ops); > >>>> return 0; > >>>> > >>>> @@ -208,18 +238,27 @@ err1: > >>>> return -ENOMEM; > >>>> } > >>>> > >>>> +/* irq number 10 cannot be used because of hw bug */ > >>>> +int dra_irqs_unused[] = { 10 }; > >>>> +struct crossbar_data cb_dra_data = { dra_irqs_unused, > >>>> + ARRAY_SIZE(dra_irqs_unused) }; > >>>> + > >>>> static const struct of_device_id crossbar_match[] __initconst = { > >>>> - { .compatible = "ti,irq-crossbar" }, > >>>> + { .compatible = "ti,irq-crossbar", .data = &cb_dra_data }, > >>>> {} > >>>> }; > >>> > >>> This is a bug in all implementations of this IP? Or, a specific > >>> SoC's implementation? Would this be better expressed in the dts via a > >>> property? Can we expect future implementations to be fixed? > >>> > >>> thx, > >>> > >>> Jason. > >> Infact this and PATCH#10 should be merged. I will change that. > >> > >> So in Socs's (2 so far) that do have a crossbar, some irqs are mapped > >> through a crossbar and some are directly wired to the irqchip. > >> These 'unused irqs' are those which are directly wired but they still > >> have a crossbar register. Their routing cannot be changed. So this > >> is not really expected usage of the crossbar hw ip. We initially thought > >> having a dts property separately for this, but took this path to avoid > >> loading the dts with additional bindings which may not be generic. > > > > How do you plan to handle future SoCs with this IP and possibly > > different hard-wired irqs? > Yes, that would require adding a new compatible in the above list and dts. > So if adding a new binding in the dts would be cleaner, then i will change > it that way. Yes, unless the DT maintainers have shot the idea down, I'd prefer to see a separate property. With the method you currently have, we'll have to change the compatible when the IP _hasn't_ changed, just because the SoC was wired differently. We could trigger on the SoC compatible and maintain a table, but that seems overly hacky when the dt is supposed to describe the hardware. thx, Jason. -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html