On Sat, Jan 27 2024 at 21:47, Anup Patel wrote:
> +static int imsic_cpu_page_phys(unsigned int cpu,
> + unsigned int guest_index,
> + phys_addr_t *out_msi_pa)
> +{
> + struct imsic_global_config *global;
> + struct imsic_local_config *local;
> +
> + global = &imsic->global;
> + local = per_cpu_ptr(global->local, cpu);
> +
> + if (BIT(global->guest_index_bits) <= guest_index)
> + return -EINVAL;
As the callsite does not care about the return value, just make this
function boolean and return true on success.
> + if (out_msi_pa)
> + *out_msi_pa = local->msi_pa +
> + (guest_index * IMSIC_MMIO_PAGE_SZ);
> +
> + return 0;
> +}
> +
> +static void imsic_irq_mask(struct irq_data *d)
> +{
> + imsic_vector_mask(irq_data_get_irq_chip_data(d));
> +}
> +
> +static void imsic_irq_unmask(struct irq_data *d)
> +{
> + imsic_vector_unmask(irq_data_get_irq_chip_data(d));
> +}
> +
> +static int imsic_irq_retrigger(struct irq_data *d)
> +{
> + struct imsic_vector *vec = irq_data_get_irq_chip_data(d);
> + struct imsic_local_config *local;
> +
> + if (WARN_ON(vec == NULL))
> + return -ENOENT;
> +
> + local = per_cpu_ptr(imsic->global.local, vec->cpu);
> + writel(vec->local_id, local->msi_va);
> + return 0;
> +}
> +
> +static void imsic_irq_compose_vector_msg(struct imsic_vector *vec,
> + struct msi_msg *msg)
> +{
> + phys_addr_t msi_addr;
> + int err;
> +
> + if (WARN_ON(vec == NULL))
> + return;
> +
> + err = imsic_cpu_page_phys(vec->cpu, 0, &msi_addr);
> + if (WARN_ON(err))
> + return;
if (WARN_ON(!imsic_cpu_page_phys(...)))
return
Hmm?
> +
> + msg->address_hi = upper_32_bits(msi_addr);
> + msg->address_lo = lower_32_bits(msi_addr);
> + msg->data = vec->local_id;
> +}
> +
> +static void imsic_irq_compose_msg(struct irq_data *d, struct msi_msg *msg)
> +{
> + imsic_irq_compose_vector_msg(irq_data_get_irq_chip_data(d), msg);
> +}
> +
> +#ifdef CONFIG_SMP
> +static void imsic_msi_update_msg(struct irq_data *d, struct imsic_vector *vec)
> +{
> + struct msi_msg msg[2] = { [1] = { }, };
> +
> + imsic_irq_compose_vector_msg(vec, msg);
> + irq_data_get_irq_chip(d)->irq_write_msi_msg(d, msg);
> +}
> +
> +static int imsic_irq_set_affinity(struct irq_data *d,
> + const struct cpumask *mask_val,
> + bool force)
> +{
> + struct imsic_vector *old_vec, *new_vec;
> + struct irq_data *pd = d->parent_data;
> +
> + old_vec = irq_data_get_irq_chip_data(pd);
> + if (WARN_ON(old_vec == NULL))
> + return -ENOENT;
> +
> + /* Get a new vector on the desired set of CPUs */
> + new_vec = imsic_vector_alloc(old_vec->hwirq, mask_val);
> + if (!new_vec)
> + return -ENOSPC;
> +
> + /* If old vector belongs to the desired CPU then do nothing */
> + if (old_vec->cpu == new_vec->cpu) {
> + imsic_vector_free(new_vec);
> + return IRQ_SET_MASK_OK_DONE;
> + }
You can spare that exercise by checking it before the allocation:
if (cpumask_test_cpu(old_vec->cpu, mask_val))
return IRQ_SET_MASK_OK_DONE;
> +
> + /* Point device to the new vector */
> + imsic_msi_update_msg(d, new_vec);
> +static int imsic_irq_domain_alloc(struct irq_domain *domain,
> + unsigned int virq, unsigned int nr_irqs,
> + void *args)
> +{
> + struct imsic_vector *vec;
> + int hwirq;
> +
> + /* Legacy-MSI or multi-MSI not supported yet. */
What's legacy MSI in that context?
> + if (nr_irqs > 1)
> + return -ENOTSUPP;
> +
> + hwirq = imsic_hwirq_alloc();
> + if (hwirq < 0)
> + return hwirq;
> +
> + vec = imsic_vector_alloc(hwirq, cpu_online_mask);
> + if (!vec) {
> + imsic_hwirq_free(hwirq);
> + return -ENOSPC;
> + }
> +
> + irq_domain_set_info(domain, virq, hwirq,
> + &imsic_irq_base_chip, vec,
> + handle_simple_irq, NULL, NULL);
> + irq_set_noprobe(virq);
> + irq_set_affinity(virq, cpu_online_mask);
> +
> + /*
> + * IMSIC does not implement irq_disable() so Linux interrupt
> + * subsystem will take a lazy approach for disabling an IMSIC
> + * interrupt. This means IMSIC interrupts are left unmasked
> + * upon system suspend and interrupts are not processed
> + * immediately upon system wake up. To tackle this, we disable
> + * the lazy approach for all IMSIC interrupts.
Why? Lazy works perfectly fine even w/o an irq_disable() callback.
> + */
> + irq_set_status_flags(virq, IRQ_DISABLE_UNLAZY);
> +
> +#define MATCH_PLATFORM_MSI BIT(DOMAIN_BUS_PLATFORM_MSI)
You really love macro indirections :)
> +static const struct msi_parent_ops imsic_msi_parent_ops = {
> + .supported_flags = MSI_GENERIC_FLAGS_MASK,
> + .required_flags = MSI_FLAG_USE_DEF_DOM_OPS |
> + MSI_FLAG_USE_DEF_CHIP_OPS,
> + .bus_select_token = DOMAIN_BUS_NEXUS,
> + .bus_select_mask = MATCH_PLATFORM_MSI,
> + .init_dev_msi_info = imsic_init_dev_msi_info,
> +};
> +
> +int imsic_irqdomain_init(void)
> +{
> + struct imsic_global_config *global;
> +
> + if (!imsic || !imsic->fwnode) {
> + pr_err("early driver not probed\n");
> + return -ENODEV;
> + }
> +
> + if (imsic->base_domain) {
> + pr_err("%pfwP: irq domain already created\n", imsic->fwnode);
> + return -ENODEV;
> + }
> +
> + global = &imsic->global;
Please move that assignment down to the usage site. Here it's just a
distraction.
> + /* Create Base IRQ domain */
> + imsic->base_domain = irq_domain_create_tree(imsic->fwnode,
> + &imsic_base_domain_ops, imsic);
> + if (!imsic->base_domain) {
> + pr_err("%pfwP: failed to create IMSIC base domain\n",
> + imsic->fwnode);
> + return -ENOMEM;
> + }
> + imsic->base_domain->flags |= IRQ_DOMAIN_FLAG_MSI_PARENT;
> + imsic->base_domain->msi_parent_ops = &imsic_msi_parent_ops;
Thanks,
tglx
