From: Marc Zyngier <maz@xxxxxxxxxx>
Commit d976c6f4b32c ("of: property: Add fw_devlink support for
interrupt-map property") tried to do what it says on the tin,
but failed on a couple of points:
- it confuses bytes and cells. Not a huge deal, except when it
comes to pointer arithmetic
- it doesn't really handle anything but interrupt-maps that have
their parent #address-cells set to 0
The combinations of the two leads to some serious fun on my M1
box, with plenty of WARN-ON() firing all over the shop, and
amusing values being generated for interrupt specifiers.
Having 2 versions of parsing code for "interrupt-map" was a bad
idea. Now that the common parsing parts have been refactored
into of_irq_parse_imap_parent(), rework the code here to use it
instead and fix the pointer arithmetic.
Note that the dependency will be a bit different than the original code
when the interrupt-map points to another interrupt-map. In this case,
the original code would resolve to the final interrupt controller. Now
the dependency is the parent interrupt-map (which itself should have a
dependency to the parent). It is possible that a node with an
interrupt-map has no driver.
Fixes: d976c6f4b32c ("of: property: Add fw_devlink support for interrupt-map property")
Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx>
Co-developed-by: Rob Herring (Arm) <robh@xxxxxxxxxx>
Cc: Anup Patel <apatel@xxxxxxxxxxxxxxxx>
Cc: Saravana Kannan <saravanak@xxxxxxxxxx>
Signed-off-by: Rob Herring (Arm) <robh@xxxxxxxxxx>
---
drivers/of/property.c | 30 ++++++++++--------------------
1 file changed, 10 insertions(+), 20 deletions(-)
diff --git a/drivers/of/property.c b/drivers/of/property.c
index 1c83e68f805b..164d77cb9445 100644
--- a/drivers/of/property.c
+++ b/drivers/of/property.c
@@ -1306,10 +1306,10 @@ static struct device_node *parse_interrupts(struct device_node *np,
static struct device_node *parse_interrupt_map(struct device_node *np,
const char *prop_name, int index)
{
- const __be32 *imap, *imap_end, *addr;
+ const __be32 *imap, *imap_end;
struct of_phandle_args sup_args;
u32 addrcells, intcells;
- int i, imaplen;
+ int imaplen;
if (!IS_ENABLED(CONFIG_OF_IRQ))
return NULL;
@@ -1322,33 +1322,23 @@ static struct device_node *parse_interrupt_map(struct device_node *np,
addrcells = of_bus_n_addr_cells(np);
imap = of_get_property(np, "interrupt-map", &imaplen);
- if (!imap || imaplen <= (addrcells + intcells))
+ imaplen /= sizeof(*imap);
+ if (!imap)
return NULL;
- imap_end = imap + imaplen;
- while (imap < imap_end) {
- addr = imap;
- imap += addrcells;
+ imap_end = imap + imaplen;
- sup_args.np = np;
- sup_args.args_count = intcells;
- for (i = 0; i < intcells; i++)
- sup_args.args[i] = be32_to_cpu(imap[i]);
- imap += intcells;
+ for (int i = 0; imap + addrcells + intcells + 1 < imap_end; i++) {
+ imap += addrcells + intcells;
- /*
- * Upon success, the function of_irq_parse_raw() returns
- * interrupt controller DT node pointer in sup_args.np.
- */
- if (of_irq_parse_raw(addr, &sup_args))
+ imap = of_irq_parse_imap_parent(imap, imap_end - imap, &sup_args);
+ if (!imap)
return NULL;
- if (!index)
+ if (i == index)
return sup_args.np;
of_node_put(sup_args.np);
- imap += sup_args.args_count + 1;
- index--;
}
return NULL;
--
2.43.0
