[RFC PATCH 06/33] irqchip/gic-v3-its: Add probing for VLPI properties
Shanker Donthineni
shankerd at codeaurora.org
Mon Feb 13 13:58:27 PST 2017
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 <marc.zyngier at arm.com>
> ---
> 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.
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