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irqchip: crossbar: Allow for quirky hardware with direct hardwiring of GIC

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On certain platforms such as DRA7, SPIs 0, 1, 2, 3, 5, 6, 10, 131,
132, 133 are direct wired to hardware blocks bypassing crossbar.
This quirky implementation is *NOT* supposed to be the expectation
of crossbar hardware usage. However, these are already marked in our
description of the hardware with SKIP and RESERVED where appropriate.

Unfortunately, we need to be able to refer to these hardwired IRQs.
So, to request these, crossbar driver can use the existing information
from it's table that these SKIP/RESERVED maps are direct wired sources
and generic allocation/programming of crossbar should be avoided.

Signed-off-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Sricharan R <r.sricharan@ti.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Link: https://lkml.kernel.org/r/1403766634-18543-17-git-send-email-r.sricharan@ti.com
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
This commit is contained in:
Nishanth Menon 2014-06-26 12:40:34 +05:30 committed by Jason Cooper
parent 9a34f73fb7
commit d360892d37
2 changed files with 28 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
Documentation/devicetree/bindings/arm/omap/crossbar.txt
View File

@ -44,8 +44,10 @@ Documentation/devicetree/bindings/arm/gic.txt for further details.
An interrupt consumer on an SoC using crossbar will use:
interrupts = <GIC_SPI request_number interrupt_level>
request number shall be between 0 to that described by
"ti,max-crossbar-sources"
When the request number is between 0 to that described by
"ti,max-crossbar-sources", it is assumed to be a crossbar mapping. If the
request_number is greater than "ti,max-crossbar-sources", then it is mapped as a
quirky hardware mapping direct to GIC.
Example:
device_x@0x4a023000 {
@ -53,3 +55,9 @@ Example:
interrupts = <GIC_SPI 8 IRQ_TYPE_LEVEL_HIGH>;
...
};
device_y@0x4a033000 {
/* Direct mapped GIC SPI 1 used */
interrupts = <GIC_SPI DIRECT_IRQ(1) IRQ_TYPE_LEVEL_HIGH>;
...
};

20
drivers/irqchip/irq-crossbar.c
View File

@ -86,8 +86,13 @@ static inline int allocate_free_irq(int cb_no)
static inline bool needs_crossbar_write(irq_hw_number_t hw)
{
if (hw > GIC_IRQ_START)
return true;
int cb_no;
if (hw > GIC_IRQ_START) {
cb_no = cb->irq_map[hw - GIC_IRQ_START];
if (cb_no != IRQ_RESERVED && cb_no != IRQ_SKIP)
return true;
}
return false;
}
@ -130,8 +135,19 @@ static int crossbar_domain_xlate(struct irq_domain *d,
{
int ret;
int req_num = intspec[1];
int direct_map_num;
if (req_num >= cb->max_crossbar_sources) {
direct_map_num = req_num - cb->max_crossbar_sources;
if (direct_map_num < cb->int_max) {
ret = cb->irq_map[direct_map_num];
if (ret == IRQ_RESERVED || ret == IRQ_SKIP) {
/* We use the interrupt num as h/w irq num */
ret = direct_map_num;
goto found;
}
}
pr_err("%s: requested crossbar number %d > max %d\n",
__func__, req_num, cb->max_crossbar_sources);
return -EINVAL;