Re: [PATCH V3 16/17] irqchip/gic: Prepare for adding platform driver
From: Jon Hunter <hidden>
Date: 2016-05-06 14:10:03
Also in:
linux-omap, linux-tegra, lkml
Hi Marc, On 05/05/16 15:13, Marc Zyngier wrote: [...]
Gahhh. No. Please. Last time we did that, it took 6 months to untangle
the mess people made by adding their own hacks in this structure,
so I definitely want to keep it completely private, forever. Same goes
for the gic_{dist,cpu.pm}_init() functions.OK.
I've had a go at this, and came up with the following patch. I've only briefly tested it on a host and a VM, so it is likely to break some stuff somewhere, but you'll get the idea: The gic_chip_data struct is entirely opaque, allocated by the GIC driver itself, with a few new fields in it so that it becomes self-contained. This applies on top of your series. It should also make it easy to switch to a model where we allocate the structure dynamically instead of the old static crap. Thoughts?
Yes I have been doing some testing and with a couple tweaks we can make something like this work. One thing that caught me out was ...
+int gic_of_setup(struct device_node *node, struct device *dev,
+ struct gic_chip_data **gicp)
+{
+ struct gic_chip_data *gic;
- *cpu_base = of_iomap(node, 1);
- if (WARN(!*cpu_base, "unable to map gic cpu registers\n")) {
- iounmap(*dist_base);
- return -ENOMEM;
+ if (!node || !gicp)
+ return -EINVAL;
+
+ if (dev) {
+ *gicp = devm_kzalloc(dev, sizeof(*gic), GFP_KERNEL);
+ if (!*gicp)
+ return -ENOMEM;
}
- if (of_property_read_u32(node, "cpu-offset", percpu_offset))
- *percpu_offset = 0;
+ gic = *gicp;
+
+ gic->raw_dist_base = of_iomap(node, 0);
+ if (WARN(!gic->raw_dist_base, "unable to map gic dist registers\n"))
+ goto err;
+
+ gic->raw_cpu_base = of_iomap(node, 1);
+ if (WARN(!gic->raw_cpu_base, "unable to map gic cpu registers\n"))
+ goto err;
+
+ if (of_property_read_u32(node, "cpu-offset", &gic->percpu_offset))
+ gic->percpu_offset = 0;
+ gic->chip.parent_device = dev;We can't initialise the device here as it gets overwritten in the gic_init_bases. So I have had to re-organise things a bit. Good news is that I have eliminated the call from the platform driver to gic_init_bases so we only have a single call to initialise the GIC. Cheers Jon