On 01/17/2017 04:20 AM, Marc Zyngier wrote:
Add the probing code for the ITS VLPI support. This includes
configuring the ITS number if not supporting the single VMOVP
command feature.
Signed-off-by: Marc Zyngier <[email protected]>
---
drivers/irqchip/irq-gic-v3-its.c | 47
++++++++++++++++++++++++++++++++++----
include/linux/irqchip/arm-gic-v3.h | 4 ++++
2 files changed, 47 insertions(+), 4 deletions(-)
diff --git a/drivers/irqchip/irq-gic-v3-its.c
b/drivers/irqchip/irq-gic-v3-its.c
index 9304dd2..99f6130 100644
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -103,6 +103,7 @@ struct its_node {
u32 ite_size;
u32 device_ids;
int numa_node;
+ bool is_v4;
};
#define ITS_ITT_ALIGN SZ_256
@@ -135,6 +136,8 @@ static DEFINE_SPINLOCK(its_lock);
static struct rdists *gic_rdists;
static struct irq_domain *its_parent;
+static unsigned long its_list_map;
+
#define gic_data_rdist() (raw_cpu_ptr(gic_rdists->rdist))
#define gic_data_rdist_rd_base() (gic_data_rdist()->rd_base)
@@ -1661,8 +1664,8 @@ static int __init its_probe_one(struct resource
*res,
{
struct its_node *its;
void __iomem *its_base;
- u32 val;
- u64 baser, tmp;
+ u32 val, ctlr;
+ u64 baser, tmp, typer;
int err;
its_base = ioremap(res->start, resource_size(res));
@@ -1695,9 +1698,44 @@ static int __init its_probe_one(struct resource
*res,
raw_spin_lock_init(&its->lock);
INIT_LIST_HEAD(&its->entry);
INIT_LIST_HEAD(&its->its_device_list);
+ typer = gic_read_typer(its_base + GITS_TYPER);
its->base = its_base;
its->phys_base = res->start;
- its->ite_size = ((gic_read_typer(its_base + GITS_TYPER) >> 4) &
0xf) + 1;
+ its->ite_size = ((typer >> 4) & 0xf) + 1;
I think we should move bit manipulations to a macro, some thing like this.
its->ite_size = GITS_TYPER_ITEBITS(typer);
#define GITS_TYPER_ITEBITS_SHIFT 4
#define GITS_TYPER_ITEBITS(r) ((((r) >>
GITS_TYPER_ITEBITS_SHIFT) & 0xf) + 1)
+ its->is_v4 = !!(typer & GITS_TYPER_VLPIS);
+ if (its->is_v4 && !(typer & GITS_TYPER_VMOVP)) {
+ int its_number;
+
+ its_number = find_first_zero_bit(&its_list_map, 16);
+ if (its_number >= 16) {
+ pr_err("ITS@%pa: No ITSList entry available!\n",
+ &res->start);
+ err = -EINVAL;
+ goto out_free_its;
+ }
+
+ ctlr = readl_relaxed(its_base + GITS_CTLR);
+ ctlr &= ~GITS_CTLR_ITS_NUMBER;
+ ctlr |= its_number << GITS_CTLR_ITS_NUMBER_SHIFT;
+ writel_relaxed(ctlr, its_base + GITS_CTLR);
+ ctlr = readl_relaxed(its_base + GITS_CTLR);
+ if ((ctlr & GITS_CTLR_ITS_NUMBER) != (its_number <<
GITS_CTLR_ITS_NUMBER_SHIFT)) {
+ its_number = ctlr & GITS_CTLR_ITS_NUMBER;
+ its_number >>= GITS_CTLR_ITS_NUMBER_SHIFT;
+ }
+
+ if (test_and_set_bit(its_number, &its_list_map)) {
+ pr_err("ITS@%pa: Duplicate ITSList entry %d\n",
+ &res->start, its_number);
+ err = -EINVAL;
+ goto out_free_its;
+ }
+
+ pr_info("ITS@%pa: Using ITS number %d\n", &res->start,
its_number);
+ } else {
+ pr_info("ITS@%pa: Single VMOVP capable\n", &res->start);
+ }
Can we move to a separate function for code readability purpose?
--
Shanker Donthineni
Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm
Technologies, Inc.
Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux
Foundation Collaborative Project.
