From 10337638bbaffa03f280a83ed23940aedc2de9ce Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Fri, 8 Apr 2022 15:15:33 +0100 Subject: [PATCH] hw/intc/arm_gicv3_cpuif: Split "update vIRQ/vFIQ" from gicv3_cpuif_virt_update() The function gicv3_cpuif_virt_update() currently sets all of vIRQ, vFIQ and the maintenance interrupt. This implies that it has to be used quite carefully -- as the comment notes, setting the maintenance interrupt will typically cause the GIC code to be re-entered recursively. For handling vLPIs, we need the redistributor to be able to tell the cpuif to update the vIRQ and vFIQ lines when the highest priority pending vLPI changes. Since that change can't cause the maintenance interrupt state to change, we can pull the "update vIRQ/vFIQ" parts of gicv3_cpuif_virt_update() out into a separate function, which the redistributor can then call without having to worry about the reentrancy issue. Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20220408141550.1271295-25-peter.maydell@linaro.org --- hw/intc/arm_gicv3_cpuif.c | 64 +++++++++++++++++++++++++++++------------------ hw/intc/gicv3_internal.h | 11 ++++++++ hw/intc/trace-events | 3 ++- 3 files changed, 53 insertions(+), 25 deletions(-) diff --git a/hw/intc/arm_gicv3_cpuif.c b/hw/intc/arm_gicv3_cpuif.c index 1a3d440a54..5fb64d4663 100644 --- a/hw/intc/arm_gicv3_cpuif.c +++ b/hw/intc/arm_gicv3_cpuif.c @@ -370,9 +370,45 @@ static uint32_t maintenance_interrupt_state(GICv3CPUState *cs) return value; } +void gicv3_cpuif_virt_irq_fiq_update(GICv3CPUState *cs) +{ + /* + * Tell the CPU about any pending virtual interrupts. + * This should only be called for changes that affect the + * vIRQ and vFIQ status and do not change the maintenance + * interrupt status. This means that unlike gicv3_cpuif_virt_update() + * this function won't recursively call back into the GIC code. + * The main use of this is when the redistributor has changed the + * highest priority pending virtual LPI. + */ + int idx; + int irqlevel = 0; + int fiqlevel = 0; + + idx = hppvi_index(cs); + trace_gicv3_cpuif_virt_update(gicv3_redist_affid(cs), idx); + if (idx >= 0) { + uint64_t lr = cs->ich_lr_el2[idx]; + + if (icv_hppi_can_preempt(cs, lr)) { + /* Virtual interrupts are simple: G0 are always FIQ, and G1 IRQ */ + if (lr & ICH_LR_EL2_GROUP) { + irqlevel = 1; + } else { + fiqlevel = 1; + } + } + } + + trace_gicv3_cpuif_virt_set_irqs(gicv3_redist_affid(cs), fiqlevel, irqlevel); + qemu_set_irq(cs->parent_vfiq, fiqlevel); + qemu_set_irq(cs->parent_virq, irqlevel); +} + static void gicv3_cpuif_virt_update(GICv3CPUState *cs) { - /* Tell the CPU about any pending virtual interrupts or + /* + * Tell the CPU about any pending virtual interrupts or * maintenance interrupts, following a change to the state * of the CPU interface relevant to virtual interrupts. * @@ -389,37 +425,17 @@ static void gicv3_cpuif_virt_update(GICv3CPUState *cs) * naturally as a result of there being no architectural * linkage between the physical and virtual GIC logic. */ - int idx; - int irqlevel = 0; - int fiqlevel = 0; - int maintlevel = 0; ARMCPU *cpu = ARM_CPU(cs->cpu); + int maintlevel = 0; - idx = hppvi_index(cs); - trace_gicv3_cpuif_virt_update(gicv3_redist_affid(cs), idx); - if (idx >= 0) { - uint64_t lr = cs->ich_lr_el2[idx]; - - if (icv_hppi_can_preempt(cs, lr)) { - /* Virtual interrupts are simple: G0 are always FIQ, and G1 IRQ */ - if (lr & ICH_LR_EL2_GROUP) { - irqlevel = 1; - } else { - fiqlevel = 1; - } - } - } + gicv3_cpuif_virt_irq_fiq_update(cs); if ((cs->ich_hcr_el2 & ICH_HCR_EL2_EN) && maintenance_interrupt_state(cs) != 0) { maintlevel = 1; } - trace_gicv3_cpuif_virt_set_irqs(gicv3_redist_affid(cs), fiqlevel, - irqlevel, maintlevel); - - qemu_set_irq(cs->parent_vfiq, fiqlevel); - qemu_set_irq(cs->parent_virq, irqlevel); + trace_gicv3_cpuif_virt_set_maint_irq(gicv3_redist_affid(cs), maintlevel); qemu_set_irq(cpu->gicv3_maintenance_interrupt, maintlevel); } diff --git a/hw/intc/gicv3_internal.h b/hw/intc/gicv3_internal.h index 8d2b4287cc..052aa96c77 100644 --- a/hw/intc/gicv3_internal.h +++ b/hw/intc/gicv3_internal.h @@ -707,6 +707,17 @@ void gicv3_init_cpuif(GICv3State *s); */ void gicv3_cpuif_update(GICv3CPUState *cs); +/* + * gicv3_cpuif_virt_irq_fiq_update: + * @cs: GICv3CPUState for the CPU to update + * + * Recalculate whether to assert the virtual IRQ or FIQ lines after + * a change to the current highest priority pending virtual interrupt. + * Note that this does not recalculate and change the maintenance + * interrupt status (for that, see gicv3_cpuif_virt_update()). + */ +void gicv3_cpuif_virt_irq_fiq_update(GICv3CPUState *cs); + static inline uint32_t gicv3_iidr(void) { /* Return the Implementer Identification Register value diff --git a/hw/intc/trace-events b/hw/intc/trace-events index 004a1006fb..36c3fe4da0 100644 --- a/hw/intc/trace-events +++ b/hw/intc/trace-events @@ -152,7 +152,8 @@ gicv3_icv_dir_write(uint32_t cpu, uint64_t val) "GICv3 ICV_DIR write cpu 0x%x va gicv3_icv_iar_read(int grp, uint32_t cpu, uint64_t val) "GICv3 ICV_IAR%d read cpu 0x%x value 0x%" PRIx64 gicv3_icv_eoir_write(int grp, uint32_t cpu, uint64_t val) "GICv3 ICV_EOIR%d write cpu 0x%x value 0x%" PRIx64 gicv3_cpuif_virt_update(uint32_t cpuid, int idx) "GICv3 CPU i/f 0x%x virt HPPI update LR index %d" -gicv3_cpuif_virt_set_irqs(uint32_t cpuid, int fiqlevel, int irqlevel, int maintlevel) "GICv3 CPU i/f 0x%x virt HPPI update: setting FIQ %d IRQ %d maintenance-irq %d" +gicv3_cpuif_virt_set_irqs(uint32_t cpuid, int fiqlevel, int irqlevel) "GICv3 CPU i/f 0x%x virt HPPI update: setting FIQ %d IRQ %d" +gicv3_cpuif_virt_set_maint_irq(uint32_t cpuid, int maintlevel) "GICv3 CPU i/f 0x%x virt HPPI update: setting maintenance-irq %d" # arm_gicv3_dist.c gicv3_dist_read(uint64_t offset, uint64_t data, unsigned size, bool secure) "GICv3 distributor read: offset 0x%" PRIx64 " data 0x%" PRIx64 " size %u secure %d" -- 2.11.0