[PATCH v5 11/14] KVM: arm64: selftests: Add basic GICv3 support

Raghavendra Rao Ananta
2021-09-13T20:51:14Z

Add basic support for ARM Generic Interrupt Controller v3.
The support provides guests to setup interrupts.

The work is inspired from kvm-unit-tests and the kernel's
GIC driver (drivers/irqchip/irq-gic-v3.c).

Signed-off-by: Raghavendra Rao Ananta <rananta@google.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
---
tools/testing/selftests/kvm/Makefile | 2 +-
.../selftests/kvm/include/aarch64/gic.h | 21 ++
tools/testing/selftests/kvm/lib/aarch64/gic.c | 95 +++++++
.../selftests/kvm/lib/aarch64/gic_private.h | 21 ++
.../selftests/kvm/lib/aarch64/gic_v3.c | 240 ++++++++++++++++++
.../selftests/kvm/lib/aarch64/gic_v3.h | 70 +++++
6 files changed, 448 insertions(+), 1 deletion(-)
create mode 100644 tools/testing/selftests/kvm/include/aarch64/gic.h
create mode 100644 tools/testing/selftests/kvm/lib/aarch64/gic.c
create mode 100644 tools/testing/selftests/kvm/lib/aarch64/gic_private.h
create mode 100644 tools/testing/selftests/kvm/lib/aarch64/gic_v3.c
create mode 100644 tools/testing/selftests/kvm/lib/aarch64/gic_v3.h

diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
index 61f0d376af99..5476a8ddef60 100644
--- a/tools/testing/selftests/kvm/Makefile
+++ b/tools/testing/selftests/kvm/Makefile
@@ -35,7 +35,7 @@ endif

LIBKVM = lib/assert.c lib/elf.c lib/io.c lib/kvm_util.c lib/rbtree.c lib/sparsebit.c lib/test_util.c lib/guest_modes.c lib/perf_test_util.c
LIBKVM_x86_64 = lib/x86_64/apic.c lib/x86_64/processor.c lib/x86_64/vmx.c lib/x86_64/svm.c lib/x86_64/ucall.c lib/x86_64/handlers.S
-LIBKVM_aarch64 = lib/aarch64/processor.c lib/aarch64/ucall.c lib/aarch64/handlers.S lib/aarch64/spinlock.c
+LIBKVM_aarch64 = lib/aarch64/processor.c lib/aarch64/ucall.c lib/aarch64/handlers.S lib/aarch64/spinlock.c lib/aarch64/gic.c lib/aarch64/gic_v3.c
LIBKVM_s390x = lib/s390x/processor.c lib/s390x/ucall.c lib/s390x/diag318_test_handler.c

TEST_GEN_PROGS_x86_64 = x86_64/cr4_cpuid_sync_test
diff --git a/tools/testing/selftests/kvm/include/aarch64/gic.h b/tools/testing/selftests/kvm/include/aarch64/gic.h
new file mode 100644
index 000000000000..85dd1e53048e
--- /dev/null
+++ b/tools/testing/selftests/kvm/include/aarch64/gic.h
@@ -0,0 +1,21 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * ARM Generic Interrupt Controller (GIC) specific defines
+ */
+
+#ifndef SELFTEST_KVM_GIC_H
+#define SELFTEST_KVM_GIC_H
+
+enum gic_type {
+ GIC_V3,
+ GIC_TYPE_MAX,
+};
+
+void gic_init(enum gic_type type, unsigned int nr_cpus,
+ void *dist_base, void *redist_base);
+void gic_irq_enable(unsigned int intid);
+void gic_irq_disable(unsigned int intid);
+unsigned int gic_get_and_ack_irq(void);
+void gic_set_eoi(unsigned int intid);
+
+#endif /* SELFTEST_KVM_GIC_H */
diff --git a/tools/testing/selftests/kvm/lib/aarch64/gic.c b/tools/testing/selftests/kvm/lib/aarch64/gic.c
new file mode 100644
index 000000000000..fff4fc27504d
--- /dev/null
+++ b/tools/testing/selftests/kvm/lib/aarch64/gic.c
@@ -0,0 +1,95 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * ARM Generic Interrupt Controller (GIC) support
+ */
+
+#include <errno.h>
+#include <linux/bits.h>
+#include <linux/sizes.h>
+
+#include "kvm_util.h"
+
+#include <gic.h>
+#include "gic_private.h"
+#include "processor.h"
+#include "spinlock.h"
+
+static const struct gic_common_ops *gic_common_ops;
+static struct spinlock gic_lock;
+
+static void gic_cpu_init(unsigned int cpu, void *redist_base)
+{
+ gic_common_ops->gic_cpu_init(cpu, redist_base);
+}
+
+static void
+gic_dist_init(enum gic_type type, unsigned int nr_cpus, void *dist_base)
+{
+ const struct gic_common_ops *gic_ops = NULL;
+
+ spin_lock(&gic_lock);
+
+ /* Distributor initialization is needed only once per VM */
+ if (gic_common_ops) {
+ spin_unlock(&gic_lock);
+ return;
+ }
+
+ if (type == GIC_V3)
+ gic_ops = &gicv3_ops;
+
+ GUEST_ASSERT(gic_ops);
+
+ gic_ops->gic_init(nr_cpus, dist_base);
+ gic_common_ops = gic_ops;
+
+ /* Make sure that the initialized data is visible to all the vCPUs */
+ dsb(sy);
+
+ spin_unlock(&gic_lock);
+}
+
+void gic_init(enum gic_type type, unsigned int nr_cpus,
+ void *dist_base, void *redist_base)
+{
+ uint32_t cpu = guest_get_vcpuid();
+
+ GUEST_ASSERT(type < GIC_TYPE_MAX);
+ GUEST_ASSERT(dist_base);
+ GUEST_ASSERT(redist_base);
+ GUEST_ASSERT(nr_cpus);
+
+ gic_dist_init(type, nr_cpus, dist_base);
+ gic_cpu_init(cpu, redist_base);
+}
+
+void gic_irq_enable(unsigned int intid)
+{
+ GUEST_ASSERT(gic_common_ops);
+ gic_common_ops->gic_irq_enable(intid);
+}
+
+void gic_irq_disable(unsigned int intid)
+{
+ GUEST_ASSERT(gic_common_ops);
+ gic_common_ops->gic_irq_disable(intid);
+}
+
+unsigned int gic_get_and_ack_irq(void)
+{
+ uint64_t irqstat;
+ unsigned int intid;
+
+ GUEST_ASSERT(gic_common_ops);
+
+ irqstat = gic_common_ops->gic_read_iar();
+ intid = irqstat & GENMASK(23, 0);
+
+ return intid;
+}
+
+void gic_set_eoi(unsigned int intid)
+{
+ GUEST_ASSERT(gic_common_ops);
+ gic_common_ops->gic_write_eoir(intid);
+}
diff --git a/tools/testing/selftests/kvm/lib/aarch64/gic_private.h b/tools/testing/selftests/kvm/lib/aarch64/gic_private.h
new file mode 100644
index 000000000000..d81d739433dc
--- /dev/null
+++ b/tools/testing/selftests/kvm/lib/aarch64/gic_private.h
@@ -0,0 +1,21 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * ARM Generic Interrupt Controller (GIC) private defines that's only
+ * shared among the GIC library code.
+ */
+
+#ifndef SELFTEST_KVM_GIC_PRIVATE_H
+#define SELFTEST_KVM_GIC_PRIVATE_H
+
+struct gic_common_ops {
+ void (*gic_init)(unsigned int nr_cpus, void *dist_base);
+ void (*gic_cpu_init)(unsigned int cpu, void *redist_base);
+ void (*gic_irq_enable)(unsigned int intid);
+ void (*gic_irq_disable)(unsigned int intid);
+ uint64_t (*gic_read_iar)(void);
+ void (*gic_write_eoir)(uint32_t irq);
+};
+
+extern const struct gic_common_ops gicv3_ops;
+
+#endif /* SELFTEST_KVM_GIC_PRIVATE_H */
diff --git a/tools/testing/selftests/kvm/lib/aarch64/gic_v3.c b/tools/testing/selftests/kvm/lib/aarch64/gic_v3.c
new file mode 100644
index 000000000000..973742285b9f
--- /dev/null
+++ b/tools/testing/selftests/kvm/lib/aarch64/gic_v3.c
@@ -0,0 +1,240 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * ARM Generic Interrupt Controller (GIC) v3 support
+ */
+
+#include <linux/sizes.h>
+
+#include "kvm_util.h"
+#include "processor.h"
+#include "delay.h"
+
+#include "gic_v3.h"
+#include "gic_private.h"
+
+struct gicv3_data {
+ void *dist_base;
+ void *redist_base[GICV3_MAX_CPUS];
+ unsigned int nr_cpus;
+ unsigned int nr_spis;
+};
+
+#define sgi_base_from_redist(redist_base) (redist_base + SZ_64K)
+
+enum gicv3_intid_range {
+ SGI_RANGE,
+ PPI_RANGE,
+ SPI_RANGE,
+ INVALID_RANGE,
+};
+
+static struct gicv3_data gicv3_data;
+
+static void gicv3_gicd_wait_for_rwp(void)
+{
+ unsigned int count = 100000; /* 1s */
+
+ while (readl(gicv3_data.dist_base + GICD_CTLR) & GICD_CTLR_RWP) {
+ GUEST_ASSERT(count--);
+ udelay(10);
+ }
+}
+
+static void gicv3_gicr_wait_for_rwp(void *redist_base)
+{
+ unsigned int count = 100000; /* 1s */
+
+ while (readl(redist_base + GICR_CTLR) & GICR_CTLR_RWP) {
+ GUEST_ASSERT(count--);
+ udelay(10);
+ }
+}
+
+static enum gicv3_intid_range get_intid_range(unsigned int intid)
+{
+ switch (intid) {
+ case 0 ... 15:
+ return SGI_RANGE;
+ case 16 ... 31:
+ return PPI_RANGE;
+ case 32 ... 1019:
+ return SPI_RANGE;
+ }
+
+ /* We should not be reaching here */
+ GUEST_ASSERT(0);
+
+ return INVALID_RANGE;
+}
+
+static uint64_t gicv3_read_iar(void)
+{
+ uint64_t irqstat = read_sysreg_s(SYS_ICC_IAR1_EL1);
+
+ dsb(sy);
+ return irqstat;
+}
+
+static void gicv3_write_eoir(uint32_t irq)
+{
+ write_sysreg_s(SYS_ICC_EOIR1_EL1, irq);
+ isb();
+}
+
+static void
+gicv3_config_irq(unsigned int intid, unsigned int offset)
+{
+ uint32_t cpu = guest_get_vcpuid();
+ uint32_t mask = 1 << (intid % 32);
+ enum gicv3_intid_range intid_range = get_intid_range(intid);
+ void *reg;
+
+ /* We care about 'cpu' only for SGIs or PPIs */
+ if (intid_range == SGI_RANGE || intid_range == PPI_RANGE) {
+ GUEST_ASSERT(cpu < gicv3_data.nr_cpus);
+
+ reg = sgi_base_from_redist(gicv3_data.redist_base[cpu]) +
+ offset;
+ writel(mask, reg);
+ gicv3_gicr_wait_for_rwp(gicv3_data.redist_base[cpu]);
+ } else if (intid_range == SPI_RANGE) {
+ reg = gicv3_data.dist_base + offset + (intid / 32) * 4;
+ writel(mask, reg);
+ gicv3_gicd_wait_for_rwp();
+ } else {
+ GUEST_ASSERT(0);
+ }
+}
+
+static void gicv3_irq_enable(unsigned int intid)
+{
+ gicv3_config_irq(intid, GICD_ISENABLER);
+}
+
+static void gicv3_irq_disable(unsigned int intid)
+{
+ gicv3_config_irq(intid, GICD_ICENABLER);
+}
+
+static void gicv3_enable_redist(void *redist_base)
+{
+ uint32_t val = readl(redist_base + GICR_WAKER);
+ unsigned int count = 100000; /* 1s */
+
+ val &= ~GICR_WAKER_ProcessorSleep;
+ writel(val, redist_base + GICR_WAKER);
+
+ /* Wait until the processor is 'active' */
+ while (readl(redist_base + GICR_WAKER) & GICR_WAKER_ChildrenAsleep) {
+ GUEST_ASSERT(count--);
+ udelay(10);
+ }
+}
+
+static inline void *gicr_base_gpa_cpu(void *redist_base, uint32_t cpu)
+{
+ /* Align all the redistributors sequentially */
+ return redist_base + cpu * SZ_64K * 2;
+}
+
+static void gicv3_cpu_init(unsigned int cpu, void *redist_base)
+{
+ void *sgi_base;
+ unsigned int i;
+ void *redist_base_cpu;
+
+ GUEST_ASSERT(cpu < gicv3_data.nr_cpus);
+
+ redist_base_cpu = gicr_base_gpa_cpu(redist_base, cpu);
+ sgi_base = sgi_base_from_redist(redist_base_cpu);
+
+ gicv3_enable_redist(redist_base_cpu);
+
+ /*
+ * Mark all the SGI and PPI interrupts as non-secure Group-1.
+ * Also, deactivate and disable them.
+ */
+ writel(~0, sgi_base + GICR_IGROUPR0);
+ writel(~0, sgi_base + GICR_ICACTIVER0);
+ writel(~0, sgi_base + GICR_ICENABLER0);
+
+ /* Set a default priority for all the SGIs and PPIs */
+ for (i = 0; i < 32; i += 4)
+ writel(GICD_INT_DEF_PRI_X4,
+ sgi_base + GICR_IPRIORITYR0 + i);
+
+ gicv3_gicr_wait_for_rwp(redist_base_cpu);
+
+ /* Enable the GIC system register (ICC_*) access */
+ write_sysreg_s(SYS_ICC_SRE_EL1,
+ read_sysreg_s(SYS_ICC_SRE_EL1) | ICC_SRE_EL1_SRE);
+
+ /* Set a default priority threshold */
+ write_sysreg_s(SYS_ICC_PMR_EL1, ICC_PMR_DEF_PRIO);
+
+ /* Enable non-secure Group-1 interrupts */
+ write_sysreg_s(SYS_ICC_GRPEN1_EL1, ICC_IGRPEN1_EL1_ENABLE);
+
+ gicv3_data.redist_base[cpu] = redist_base_cpu;
+}
+
+static void gicv3_dist_init(void)
+{
+ void *dist_base = gicv3_data.dist_base;
+ unsigned int i;
+
+ /* Disable the distributor until we set things up */
+ writel(0, dist_base + GICD_CTLR);
+ gicv3_gicd_wait_for_rwp();
+
+ /*
+ * Mark all the SPI interrupts as non-secure Group-1.
+ * Also, deactivate and disable them.
+ */
+ for (i = 32; i < gicv3_data.nr_spis; i += 32) {
+ writel(~0, dist_base + GICD_IGROUPR + i / 8);
+ writel(~0, dist_base + GICD_ICACTIVER + i / 8);
+ writel(~0, dist_base + GICD_ICENABLER + i / 8);
+ }
+
+ /* Set a default priority for all the SPIs */
+ for (i = 32; i < gicv3_data.nr_spis; i += 4)
+ writel(GICD_INT_DEF_PRI_X4,
+ dist_base + GICD_IPRIORITYR + i);
+
+ /* Wait for the settings to sync-in */
+ gicv3_gicd_wait_for_rwp();
+
+ /* Finally, enable the distributor globally with ARE */
+ writel(GICD_CTLR_ARE_NS | GICD_CTLR_ENABLE_G1A |
+ GICD_CTLR_ENABLE_G1, dist_base + GICD_CTLR);
+ gicv3_gicd_wait_for_rwp();
+}
+
+static void gicv3_init(unsigned int nr_cpus, void *dist_base)
+{
+ GUEST_ASSERT(nr_cpus <= GICV3_MAX_CPUS);
+
+ gicv3_data.nr_cpus = nr_cpus;
+ gicv3_data.dist_base = dist_base;
+ gicv3_data.nr_spis = GICD_TYPER_SPIS(
+ readl(gicv3_data.dist_base + GICD_TYPER));
+ if (gicv3_data.nr_spis > 1020)
+ gicv3_data.nr_spis = 1020;
+
+ /*
+ * Initialize only the distributor for now.
+ * The redistributor and CPU interfaces are initialized
+ * later for every PE.
+ */
+ gicv3_dist_init();
+}
+
+const struct gic_common_ops gicv3_ops = {
+ .gic_init = gicv3_init,
+ .gic_cpu_init = gicv3_cpu_init,
+ .gic_irq_enable = gicv3_irq_enable,
+ .gic_irq_disable = gicv3_irq_disable,
+ .gic_read_iar = gicv3_read_iar,
+ .gic_write_eoir = gicv3_write_eoir,
+};
diff --git a/tools/testing/selftests/kvm/lib/aarch64/gic_v3.h b/tools/testing/selftests/kvm/lib/aarch64/gic_v3.h
new file mode 100644
index 000000000000..b51536d469a6
--- /dev/null
+++ b/tools/testing/selftests/kvm/lib/aarch64/gic_v3.h
@@ -0,0 +1,70 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * ARM Generic Interrupt Controller (GIC) v3 specific defines
+ */
+
+#ifndef SELFTEST_KVM_GICV3_H
+#define SELFTEST_KVM_GICV3_H
+
+#include <asm/sysreg.h>
+
+/*
+ * Distributor registers
+ */
+#define GICD_CTLR 0x0000
+#define GICD_TYPER 0x0004
+#define GICD_IGROUPR 0x0080
+#define GICD_ISENABLER 0x0100
+#define GICD_ICENABLER 0x0180
+#define GICD_ICACTIVER 0x0380
+#define GICD_IPRIORITYR 0x0400
+
+/*
+ * The assumption is that the guest runs in a non-secure mode.
+ * The following bits of GICD_CTLR are defined accordingly.
+ */
+#define GICD_CTLR_RWP (1U << 31)
+#define GICD_CTLR_nASSGIreq (1U << 8)
+#define GICD_CTLR_ARE_NS (1U << 4)
+#define GICD_CTLR_ENABLE_G1A (1U << 1)
+#define GICD_CTLR_ENABLE_G1 (1U << 0)
+
+#define GICD_TYPER_SPIS(typer) ((((typer) & 0x1f) + 1) * 32)
+#define GICD_INT_DEF_PRI_X4 0xa0a0a0a0
+
+/*
+ * Redistributor registers
+ */
+#define GICR_CTLR 0x000
+#define GICR_WAKER 0x014
+
+#define GICR_CTLR_RWP (1U << 3)
+
+#define GICR_WAKER_ProcessorSleep (1U << 1)
+#define GICR_WAKER_ChildrenAsleep (1U << 2)
+
+/*
+ * Redistributor registers, offsets from SGI base
+ */
+#define GICR_IGROUPR0 GICD_IGROUPR
+#define GICR_ISENABLER0 GICD_ISENABLER
+#define GICR_ICENABLER0 GICD_ICENABLER
+#define GICR_ICACTIVER0 GICD_ICACTIVER
+#define GICR_IPRIORITYR0 GICD_IPRIORITYR
+
+/* CPU interface registers */
+#define SYS_ICC_PMR_EL1 sys_reg(3, 0, 4, 6, 0)
+#define SYS_ICC_IAR1_EL1 sys_reg(3, 0, 12, 12, 0)
+#define SYS_ICC_EOIR1_EL1 sys_reg(3, 0, 12, 12, 1)
+#define SYS_ICC_SRE_EL1 sys_reg(3, 0, 12, 12, 5)
+#define SYS_ICC_GRPEN1_EL1 sys_reg(3, 0, 12, 12, 7)
+
+#define ICC_PMR_DEF_PRIO 0xf0
+
+#define ICC_SRE_EL1_SRE (1U << 0)
+
+#define ICC_IGRPEN1_EL1_ENABLE (1U << 0)
+
+#define GICV3_MAX_CPUS 512
+
+#endif /* SELFTEST_KVM_GICV3_H */
--
2.33.0.309.g3052b89438-goog