On Mon, Apr 29, 2024 at 9:08 PM Anup Patel <apatel@xxxxxxxxxxxxxxxx> wrote:
>
> Some of the PCI controllers (such as generic PCI host controller)
> use "interrupt-map" DT property to describe the mapping between
> PCI endpoints and PCI interrupt pins. This the only case where
> the interrupts are not described in DT.
>
> Currently, there is no fw_devlink created based on "interrupt-map"
> DT property so interrupt controller is not guaranteed to be probed
> before PCI host controller. This affects every platform where both
> PCI host controller and interrupt controllers are probed as regular
> platform devices.
>
> This creates fw_devlink between consumers (PCI host controller) and
> supplier (interrupt controller) based on "interrupt-map" DT property.
>
> Signed-off-by: Anup Patel <apatel@xxxxxxxxxxxxxxxx>
> ---
> Changes since v2:
> - No need for a loop to find #interrupt-cells property value
> - Fix node de-reference leak when index is greater than number
> of entries in interrupt-map property
> Changes since v1:
> - Updated commit description based on Rob's suggestion
> - Use of_irq_parse_raw() for parsing interrupt-map DT property
> ---
> drivers/of/property.c | 50 +++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 50 insertions(+)
>
> diff --git a/drivers/of/property.c b/drivers/of/property.c
> index a6358ee99b74..7326ca07adfe 100644
> --- a/drivers/of/property.c
> +++ b/drivers/of/property.c
> @@ -1311,6 +1311,55 @@ static struct device_node *parse_interrupts(struct device_node *np,
> return of_irq_parse_one(np, index, &sup_args) ? NULL : sup_args.np;
> }
>
> +static struct device_node *parse_interrupt_map(struct device_node *np,
> + const char *prop_name, int index)
> +{
> + const __be32 *imap, *imap_end, *addr;
> + struct of_phandle_args sup_args;
> + u32 addrcells, intcells;
> + int i, imaplen;
> +
> + if (!IS_ENABLED(CONFIG_OF_IRQ))
> + return NULL;
> +
> + if (strcmp(prop_name, "interrupt-map"))
> + return NULL;
> +
> + if (of_property_read_u32(np, "#interrupt-cells", &intcells))
> + return NULL;
> + addrcells = of_bus_n_addr_cells(np);
> +
> + imap = of_get_property(np, "interrupt-map", &imaplen);
> + if (!imap || imaplen <= (addrcells + intcells))
> + return NULL;
> + imap_end = imap + imaplen;
> +
> + sup_args.np = NULL;
> + while (imap < imap_end) {
> + addr = imap;
> + imap += addrcells;
> +
> + 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;
> +
> + if (of_irq_parse_raw(addr, &sup_args))
Can you leave a comment above this call saying of_irq_parse_raw()
updates sup_args.np? It's really a problem with the function IMO, but
a comment here would be helpful.
> + return NULL;
> +
> + if (!index)
> + return sup_args.np;
> +
> + of_node_put(sup_args.np);
> + sup_args.np = NULL;
Why do you need to set it to NULL? Can we just delete this line?
If you take care of these minor comments, then
Reviewed-by: Saravana Kannan <saravanak@xxxxxxxxxx>
-Saravana
> + imap += sup_args.args_count + 1;
> + index--;
> + }
> +
> + return NULL;
> +}
> +
> static struct device_node *parse_remote_endpoint(struct device_node *np,
> const char *prop_name,
> int index)
> @@ -1359,6 +1408,7 @@ static const struct supplier_bindings of_supplier_bindings[] = {
> { .parse_prop = parse_msi_parent, },
> { .parse_prop = parse_gpio_compat, },
> { .parse_prop = parse_interrupts, },
> + { .parse_prop = parse_interrupt_map, },
> { .parse_prop = parse_regulators, },
> { .parse_prop = parse_gpio, },
> { .parse_prop = parse_gpios, },
> --
> 2.34.1
>
