summaryrefslogtreecommitdiff
path: root/drivers/irqchip/irq-gic-v3-its.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/irqchip/irq-gic-v3-its.c')
-rw-r--r--drivers/irqchip/irq-gic-v3-its.c101
1 files changed, 79 insertions, 22 deletions
diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index 7f2a45445b00..c3aba3fc818d 100644
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -97,9 +97,14 @@ struct its_device;
* The ITS structure - contains most of the infrastructure, with the
* top-level MSI domain, the command queue, the collections, and the
* list of devices writing to it.
+ *
+ * dev_alloc_lock has to be taken for device allocations, while the
+ * spinlock must be taken to parse data structures such as the device
+ * list.
*/
struct its_node {
raw_spinlock_t lock;
+ struct mutex dev_alloc_lock;
struct list_head entry;
void __iomem *base;
phys_addr_t phys_base;
@@ -156,6 +161,7 @@ struct its_device {
void *itt;
u32 nr_ites;
u32 device_id;
+ bool shared;
};
static struct {
@@ -1580,6 +1586,9 @@ static unsigned long *its_lpi_alloc(int nr_irqs, u32 *base, int *nr_ids)
nr_irqs /= 2;
} while (nr_irqs > 0);
+ if (!nr_irqs)
+ err = -ENOSPC;
+
if (err)
goto out;
@@ -2059,6 +2068,29 @@ static int __init allocate_lpi_tables(void)
return 0;
}
+static u64 its_clear_vpend_valid(void __iomem *vlpi_base)
+{
+ u32 count = 1000000; /* 1s! */
+ bool clean;
+ u64 val;
+
+ val = gits_read_vpendbaser(vlpi_base + GICR_VPENDBASER);
+ val &= ~GICR_VPENDBASER_Valid;
+ gits_write_vpendbaser(val, vlpi_base + GICR_VPENDBASER);
+
+ do {
+ val = gits_read_vpendbaser(vlpi_base + GICR_VPENDBASER);
+ clean = !(val & GICR_VPENDBASER_Dirty);
+ if (!clean) {
+ count--;
+ cpu_relax();
+ udelay(1);
+ }
+ } while (!clean && count);
+
+ return val;
+}
+
static void its_cpu_init_lpis(void)
{
void __iomem *rbase = gic_data_rdist_rd_base();
@@ -2144,6 +2176,30 @@ static void its_cpu_init_lpis(void)
val |= GICR_CTLR_ENABLE_LPIS;
writel_relaxed(val, rbase + GICR_CTLR);
+ if (gic_rdists->has_vlpis) {
+ void __iomem *vlpi_base = gic_data_rdist_vlpi_base();
+
+ /*
+ * It's possible for CPU to receive VLPIs before it is
+ * sheduled as a vPE, especially for the first CPU, and the
+ * VLPI with INTID larger than 2^(IDbits+1) will be considered
+ * as out of range and dropped by GIC.
+ * So we initialize IDbits to known value to avoid VLPI drop.
+ */
+ val = (LPI_NRBITS - 1) & GICR_VPROPBASER_IDBITS_MASK;
+ pr_debug("GICv4: CPU%d: Init IDbits to 0x%llx for GICR_VPROPBASER\n",
+ smp_processor_id(), val);
+ gits_write_vpropbaser(val, vlpi_base + GICR_VPROPBASER);
+
+ /*
+ * Also clear Valid bit of GICR_VPENDBASER, in case some
+ * ancient programming gets left in and has possibility of
+ * corrupting memory.
+ */
+ val = its_clear_vpend_valid(vlpi_base);
+ WARN_ON(val & GICR_VPENDBASER_Dirty);
+ }
+
/* Make sure the GIC has seen the above */
dsb(sy);
out:
@@ -2422,6 +2478,7 @@ static int its_msi_prepare(struct irq_domain *domain, struct device *dev,
struct its_device *its_dev;
struct msi_domain_info *msi_info;
u32 dev_id;
+ int err = 0;
/*
* We ignore "dev" entierely, and rely on the dev_id that has
@@ -2444,6 +2501,7 @@ static int its_msi_prepare(struct irq_domain *domain, struct device *dev,
return -EINVAL;
}
+ mutex_lock(&its->dev_alloc_lock);
its_dev = its_find_device(its, dev_id);
if (its_dev) {
/*
@@ -2451,18 +2509,22 @@ static int its_msi_prepare(struct irq_domain *domain, struct device *dev,
* another alias (PCI bridge of some sort). No need to
* create the device.
*/
+ its_dev->shared = true;
pr_debug("Reusing ITT for devID %x\n", dev_id);
goto out;
}
its_dev = its_create_device(its, dev_id, nvec, true);
- if (!its_dev)
- return -ENOMEM;
+ if (!its_dev) {
+ err = -ENOMEM;
+ goto out;
+ }
pr_debug("ITT %d entries, %d bits\n", nvec, ilog2(nvec));
out:
+ mutex_unlock(&its->dev_alloc_lock);
info->scratchpad[0].ptr = its_dev;
- return 0;
+ return err;
}
static struct msi_domain_ops its_msi_domain_ops = {
@@ -2566,6 +2628,7 @@ static void its_irq_domain_free(struct irq_domain *domain, unsigned int virq,
{
struct irq_data *d = irq_domain_get_irq_data(domain, virq);
struct its_device *its_dev = irq_data_get_irq_chip_data(d);
+ struct its_node *its = its_dev->its;
int i;
for (i = 0; i < nr_irqs; i++) {
@@ -2580,8 +2643,14 @@ static void its_irq_domain_free(struct irq_domain *domain, unsigned int virq,
irq_domain_reset_irq_data(data);
}
- /* If all interrupts have been freed, start mopping the floor */
- if (bitmap_empty(its_dev->event_map.lpi_map,
+ mutex_lock(&its->dev_alloc_lock);
+
+ /*
+ * If all interrupts have been freed, start mopping the
+ * floor. This is conditionned on the device not being shared.
+ */
+ if (!its_dev->shared &&
+ bitmap_empty(its_dev->event_map.lpi_map,
its_dev->event_map.nr_lpis)) {
its_lpi_free(its_dev->event_map.lpi_map,
its_dev->event_map.lpi_base,
@@ -2593,6 +2662,8 @@ static void its_irq_domain_free(struct irq_domain *domain, unsigned int virq,
its_free_device(its_dev);
}
+ mutex_unlock(&its->dev_alloc_lock);
+
irq_domain_free_irqs_parent(domain, virq, nr_irqs);
}
@@ -2755,26 +2826,11 @@ static void its_vpe_schedule(struct its_vpe *vpe)
static void its_vpe_deschedule(struct its_vpe *vpe)
{
void __iomem *vlpi_base = gic_data_rdist_vlpi_base();
- u32 count = 1000000; /* 1s! */
- bool clean;
u64 val;
- /* We're being scheduled out */
- val = gits_read_vpendbaser(vlpi_base + GICR_VPENDBASER);
- val &= ~GICR_VPENDBASER_Valid;
- gits_write_vpendbaser(val, vlpi_base + GICR_VPENDBASER);
-
- do {
- val = gits_read_vpendbaser(vlpi_base + GICR_VPENDBASER);
- clean = !(val & GICR_VPENDBASER_Dirty);
- if (!clean) {
- count--;
- cpu_relax();
- udelay(1);
- }
- } while (!clean && count);
+ val = its_clear_vpend_valid(vlpi_base);
- if (unlikely(!clean && !count)) {
+ if (unlikely(val & GICR_VPENDBASER_Dirty)) {
pr_err_ratelimited("ITS virtual pending table not cleaning\n");
vpe->idai = false;
vpe->pending_last = true;
@@ -3517,6 +3573,7 @@ static int __init its_probe_one(struct resource *res,
}
raw_spin_lock_init(&its->lock);
+ mutex_init(&its->dev_alloc_lock);
INIT_LIST_HEAD(&its->entry);
INIT_LIST_HEAD(&its->its_device_list);
typer = gic_read_typer(its_base + GITS_TYPER);