[RFC PATCH 10/33] irqchip/gic-v4-its: Allow use of indirect VCPU tables

From: Marc Zyngier
Date: Tue Jan 17 2017 - 05:21:34 EST


The VCPU tables can be quite sparse as well, and it makes sense
to use indirect tables as well if possible.

Signed-off-by: Marc Zyngier <marc.zyngier@xxxxxxx>
---
drivers/irqchip/irq-gic-v3-its.c | 20 +++++++++++++-------
1 file changed, 13 insertions(+), 7 deletions(-)

diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index c92ff4d..14305db1 100644
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -1060,10 +1060,13 @@ static int its_setup_baser(struct its_node *its, struct its_baser *baser,
return 0;
}

-static bool its_parse_baser_device(struct its_node *its, struct its_baser *baser,
- u32 psz, u32 *order)
+static bool its_parse_indirect_baser(struct its_node *its,
+ struct its_baser *baser,
+ u32 psz, u32 *order)
{
- u64 esz = GITS_BASER_ENTRY_SIZE(its_read_baser(its, baser));
+ u64 tmp = its_read_baser(its, baser);
+ u64 type = GITS_BASER_TYPE(tmp);
+ u64 esz = GITS_BASER_ENTRY_SIZE(tmp);
u64 val = GITS_BASER_InnerShareable | GITS_BASER_WaWb;
u32 ids = its->device_ids;
u32 new_order = *order;
@@ -1102,8 +1105,9 @@ static bool its_parse_baser_device(struct its_node *its, struct its_baser *baser
if (new_order >= MAX_ORDER) {
new_order = MAX_ORDER - 1;
ids = ilog2(PAGE_ORDER_TO_SIZE(new_order) / (int)esz);
- pr_warn("ITS@%pa: Device Table too large, reduce ids %u->%u\n",
- &its->phys_base, its->device_ids, ids);
+ pr_warn("ITS@%pa: %s Table too large, reduce ids %u->%u\n",
+ &its->phys_base, its_base_type_string[type],
+ its->device_ids, ids);
}

*order = new_order;
@@ -1154,8 +1158,10 @@ static int its_alloc_tables(struct its_node *its)
if (type == GITS_BASER_TYPE_NONE)
continue;

- if (type == GITS_BASER_TYPE_DEVICE)
- indirect = its_parse_baser_device(its, baser, psz, &order);
+ if (type == GITS_BASER_TYPE_DEVICE ||
+ type == GITS_BASER_TYPE_VCPU)
+ indirect = its_parse_indirect_baser(its, baser,
+ psz, &order);

err = its_setup_baser(its, baser, cache, shr, psz, order, indirect);
if (err < 0) {
--
2.1.4