1 // SPDX-License-Identifier: GPL-2.0-only
13 #include <linux/irqchip/arm-gic-v4.h>
17  * intricacies of GICv3, GICv4, and how a guest's view of a GICv3 gets
25  * agnostic actually means KVM-specific - what were you thinking?).
30  * - Any guest-visible VLPI is backed by a Linux interrupt (and a
31  *   physical LPI which gets unmapped when the guest maps the
33  *   mapped to the LPI (host) or the VLPI (guest). Note that this is
36  * - Enabling/disabling a VLPI is done by issuing mask/unmask calls.
38  * - Guest INT/CLEAR commands are implemented through
41  * - The *bizarre* stuff (mapping/unmapping an interrupt to a VLPI, or
59  * But handling VLPIs is only one side of the job of the GICv4
60  * code. The other (darker) side is to take care of the doorbell
61  * interrupts which are delivered when a VLPI targeting a non-running
70  * - VMs (or rather the VM abstraction that matters to the GIC)
75  * - mask/unmask do what is expected on the doorbell interrupt.
77  * - irq_set_affinity is used to move a VPE from one redistributor to
80  * - irq_set_vcpu_affinity once again gets hijacked for the purpose of
81  *   creating a new sub-API, namely scheduling/descheduling a VPE
126 	name = kasprintf(GFP_KERNEL, "GICv4-sgi-%d", task_pid_nr(current));  in its_alloc_vcpu_sgis()
130 	vpe->fwnode = irq_domain_alloc_named_id_fwnode(name, idx);  in its_alloc_vcpu_sgis()
131 	if (!vpe->fwnode)  in its_alloc_vcpu_sgis()
137 	vpe->sgi_domain = irq_domain_create_linear(vpe->fwnode, 16,  in its_alloc_vcpu_sgis()
139 	if (!vpe->sgi_domain)  in its_alloc_vcpu_sgis()
142 	sgi_base = __irq_domain_alloc_irqs(vpe->sgi_domain, -1, 16,  in its_alloc_vcpu_sgis()
151 	if (vpe->sgi_domain)  in its_alloc_vcpu_sgis()
152 		irq_domain_remove(vpe->sgi_domain);  in its_alloc_vcpu_sgis()
153 	if (vpe->fwnode)  in its_alloc_vcpu_sgis()
154 		irq_domain_free_fwnode(vpe->fwnode);  in its_alloc_vcpu_sgis()
156 	return -ENOMEM;  in its_alloc_vcpu_sgis()
163 	vm->fwnode = irq_domain_alloc_named_id_fwnode("GICv4-vpe",  in its_alloc_vcpu_irqs()
165 	if (!vm->fwnode)  in its_alloc_vcpu_irqs()
168 	vm->domain = irq_domain_create_hierarchy(gic_domain, 0, vm->nr_vpes,  in its_alloc_vcpu_irqs()
169 						 vm->fwnode, vpe_domain_ops,  in its_alloc_vcpu_irqs()
171 	if (!vm->domain)  in its_alloc_vcpu_irqs()
174 	for (i = 0; i < vm->nr_vpes; i++) {  in its_alloc_vcpu_irqs()
175 		vm->vpes[i]->its_vm = vm;  in its_alloc_vcpu_irqs()
176 		vm->vpes[i]->idai = true;  in its_alloc_vcpu_irqs()
179 	vpe_base_irq = __irq_domain_alloc_irqs(vm->domain, -1, vm->nr_vpes,  in its_alloc_vcpu_irqs()
185 	for (i = 0; i < vm->nr_vpes; i++) {  in its_alloc_vcpu_irqs()
187 		vm->vpes[i]->irq = vpe_base_irq + i;  in its_alloc_vcpu_irqs()
188 		ret = its_alloc_vcpu_sgis(vm->vpes[i], i);  in its_alloc_vcpu_irqs()
196 	if (vm->domain)  in its_alloc_vcpu_irqs()
197 		irq_domain_remove(vm->domain);  in its_alloc_vcpu_irqs()
198 	if (vm->fwnode)  in its_alloc_vcpu_irqs()
199 		irq_domain_free_fwnode(vm->fwnode);  in its_alloc_vcpu_irqs()
201 	return -ENOMEM;  in its_alloc_vcpu_irqs()
211 	for (i = 0; i < vm->nr_vpes; i++) {  in its_free_sgi_irqs()
212 		unsigned int irq = irq_find_mapping(vm->vpes[i]->sgi_domain, 0);  in its_free_sgi_irqs()
218 		irq_domain_remove(vm->vpes[i]->sgi_domain);  in its_free_sgi_irqs()
219 		irq_domain_free_fwnode(vm->vpes[i]->fwnode);  in its_free_sgi_irqs()
226 	irq_domain_free_irqs(vm->vpes[0]->irq, vm->nr_vpes);  in its_free_vcpu_irqs()
227 	irq_domain_remove(vm->domain);  in its_free_vcpu_irqs()
228 	irq_domain_free_fwnode(vm->fwnode);  in its_free_vcpu_irqs()
233 	return irq_set_vcpu_affinity(vpe->irq, info);  in its_send_vpe_cmd()
238 	struct irq_desc *desc = irq_to_desc(vpe->irq);  in its_make_vpe_non_resident()
250 		while (db && irqd_irq_disabled(&desc->irq_data))  in its_make_vpe_non_resident()
251 			enable_irq(vpe->irq);  in its_make_vpe_non_resident()
256 		vpe->resident = false;  in its_make_vpe_non_resident()
258 	vpe->ready = false;  in its_make_vpe_non_resident()
275 		/* Disabled the doorbell, as we're about to enter the guest */  in its_make_vpe_resident()
276 		disable_irq_nosync(vpe->irq);  in its_make_vpe_resident()
281 		vpe->resident = true;  in its_make_vpe_resident()
297 		vpe->ready = true;  in its_commit_vpe()
391 	return -ENODEV;  in its_init_v4()