On Fri, Oct 25 2024 at 15:45, Stanimir Varbanov wrote:
> Add an interrupt controller driver for MSI-X Interrupt Peripheral (MIP)
> hardware block found in bcm2712. The interrupt controller is used to
> handle MSI-X interrupts from peripherials behind PCIe endpoints like
> RP1 south bridge found in RPi5.
>
> There are two MIPs on bcm2712, the first has 64 consecutive SPIs
> assigned to 64 output vectors, and the second has 17 SPIs, but only
> 8 of them are consecutive starting at the 8th output vector.
This starts to converge nicely. Just a few remaining nitpicks.
> +static int mip_alloc_hwirq(struct mip_priv *mip, unsigned int nr_irqs,
> + unsigned int *hwirq)
> +{
> + int bit;
> +
> + spin_lock(&mip->lock);
> + bit = bitmap_find_free_region(mip->bitmap, mip->num_msis,
> + ilog2(nr_irqs));
> + spin_unlock(&mip->lock);
This should be
scoped_guard(spinlock, &mip->lock)
bit = bitmap_find_free_region(mip->bitmap, mip->num_msis, ilog2(nr_irqs));
> + if (bit < 0)
> + return bit;
> +
> + if (hwirq)
> + *hwirq = bit;
But what's the point of this conditional? The only call site hands in a
valid pointer, no?
> + return 0;
And therefore the whole thing can be simplified to:
static int mip_alloc_hwirq(struct mip_priv *mip, unsigned int nr_irqs)
{
guard(spinlock)(&mip_lock);
return bitmap_find_free_region(mip->bitmap, mip->num_msis, ilog2(nr_irqs));
}
and the callsite becomes:
irq = mip_alloc_hwirq(mip, nr_irqs);
if (irq < 0)
return irq;
Hmm?
> +}
> +
> +static void mip_free_hwirq(struct mip_priv *mip, unsigned int hwirq,
> + unsigned int nr_irqs)
> +{
> + spin_lock(&mip->lock);
guard(spinlock)(&mip->lock);
> + bitmap_release_region(mip->bitmap, hwirq, ilog2(nr_irqs));
> + spin_unlock(&mip->lock);
> +}
> + ret = irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, &fwspec);
> + if (ret) {
> + mip_free_hwirq(mip, irq, nr_irqs);
> + return ret;
goto err_free_hwirq; ?
> + }
> +
> + for (i = 0; i < nr_irqs; i++) {
> + irqd = irq_domain_get_irq_data(domain->parent, virq + i);
> + irqd->chip->irq_set_type(irqd, IRQ_TYPE_EDGE_RISING);
> +
> + ret = irq_domain_set_hwirq_and_chip(domain, virq + i, hwirq + i,
> + &mip_middle_irq_chip, mip);
> + if (ret)
> + goto err_free;
> +
> + irqd = irq_get_irq_data(virq + i);
> + irqd_set_single_target(irqd);
> + irqd_set_affinity_on_activate(irqd);
> + }
> +
> + return 0;
> +
> +err_free:
> + irq_domain_free_irqs_parent(domain, virq, nr_irqs);
> + mip_free_hwirq(mip, irq, nr_irqs);
> + return ret;
> +}
> +
> +static int __init mip_of_msi_init(struct device_node *node,
> + struct device_node *parent)
No line break required here.
> +{
> + struct platform_device *pdev;
> + struct mip_priv *mip;
> + int ret;
> +
> + pdev = of_find_device_by_node(node);
> + of_node_put(node);
> + if (!pdev)
> + return -EPROBE_DEFER;
> +
> + mip = kzalloc(sizeof(*mip), GFP_KERNEL);
> + if (!mip)
> + return -ENOMEM;
> +
> + spin_lock_init(&mip->lock);
> + mip->dev = &pdev->dev;
> +
> + ret = mip_parse_dt(mip, node);
> + if (ret)
> + goto err_priv;
> +
> + mip->base = of_iomap(node, 0);
> + if (!mip->base) {
> + ret = -ENXIO;
> + goto err_priv;
> + }
> +
> + mip->bitmap = bitmap_zalloc(mip->num_msis, GFP_KERNEL);
> + if (!mip->bitmap) {
> + ret = -ENOMEM;
> + goto err_base;
> + }
> +
> + /*
> + * All MSI-X masked in for the host, masked out for the
> + * VPU, and edge-triggered.
> + */
> + writel(0, mip->base + MIP_INT_MASKL_HOST);
> + writel(0, mip->base + MIP_INT_MASKH_HOST);
> + writel(~0, mip->base + MIP_INT_MASKL_VPU);
> + writel(~0, mip->base + MIP_INT_MASKH_VPU);
> + writel(~0, mip->base + MIP_INT_CFGL_HOST);
> + writel(~0, mip->base + MIP_INT_CFGH_HOST);
What undoes that in case mpi_init_domains() fails? Or is it harmless? I
really have no idea what masked in and masked out means here.
> + dev_dbg(&pdev->dev,
> + "MIP: MSI-X count: %u, base: %u, offset: %u, msg_addr: %llx\n",
Please move the string up. You have 100 characters width available.
> + mip->num_msis, mip->msi_base, mip->msi_offset, mip->msg_addr);
Thanks,
tglx
