Re: [RFC PATCH] of: platform: Skip mapping of interrupts in of_device_alloc()
From: Rob Herring <robh+dt@kernel.org>
Date: 2021-12-09 03:08:25
Also in:
linux-renesas-soc, lkml
On Wed, Dec 8, 2021 at 6:11 PM Lad Prabhakar [off-list ref] wrote:
quoted hunk ↗ jump to hunk
of_device_alloc() in early boot stage creates a interrupt mapping if there exists a "interrupts" property in the node. For hierarchical interrupt domains using "interrupts" property in the node bypassed the hierarchical setup and messed up the irq setup. This patch adds a check in of_device_alloc() to skip interrupt mapping if "not-interrupt-producer" property is present in the node. This allows nodes to describe the interrupts using "interrupts" property. Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> --- Hi All, Spawning from discussion [1], here is simple patch (not the ideal probably welcome for suggestions) from stopping the OF code from creating a map for the interrupts when using "interrupts" property. [1] https://lore.kernel.org/lkml/87pmqrck2m.wl-maz@kernel.org/ (local) T/#mbd1e47c1981082aded4b32a52e2c04291e515508 Cheers, Prabhakar --- drivers/of/platform.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-)diff --git a/drivers/of/platform.c b/drivers/of/platform.c index b3faf89744aa..629776ca1721 100644 --- a/drivers/of/platform.c +++ b/drivers/of/platform.c@@ -114,7 +114,7 @@ struct platform_device *of_device_alloc(struct device_node *np, struct device *parent) { struct platform_device *dev; - int rc, i, num_reg = 0, num_irq; + int rc, i, num_reg = 0, num_irq = 0; struct resource *res, temp_res; dev = platform_device_alloc("", PLATFORM_DEVID_NONE);@@ -124,7 +124,14 @@ struct platform_device *of_device_alloc(struct device_node *np, /* count the io and irq resources */ while (of_address_to_resource(np, num_reg, &temp_res) == 0) num_reg++; - num_irq = of_irq_count(np); + + /* + * we don't want to map the interrupts of hierarchical interrupt domain + * into the parent domain yet. This will be the job of the hierarchical + * interrupt driver code to map the interrupts as and when needed. + */ + if (!of_property_read_bool(np, "not-interrupt-producer")) + num_irq = of_irq_count(np);
The property won't fly for sure. A compatible match table could work here, but I don't really want another temporary solution.
quoted hunk ↗ jump to hunk
/* Populate the resource table */ if (num_irq || num_reg) {@@ -140,7 +147,7 @@ struct platform_device *of_device_alloc(struct device_node *np, rc = of_address_to_resource(np, i, res); WARN_ON(rc); } - if (of_irq_to_resource_table(np, res, num_irq) != num_irq) + if (num_irq && of_irq_to_resource_table(np, res, num_irq) != num_irq)
You might want to look at commit 9ec36cafe43b ("of/irq: do irq
resolution in platform_get_irq"). The intent was to remove this code,
but looks like the cleanup has a ways to go 7 years on. Primarily,
it's convert any platform_get_resource(pdev, IORESOURCE_IRQ, n) call
to platform_get_irq(). There's ~169 of those.
There are probably some open coded accesses to pdev->resources too,
but I didn't spot any.
Rob