Re: [RFC PATCH 01/33] irqchip/gic-v3: Add redistributor iterator
From: Auger Eric
Date: Thu Feb 16 2017 - 07:48:03 EST
Hi Marc,
On 17/01/2017 11:20, Marc Zyngier wrote:
> In order to discover the VLPI properties, we need to iterate over
> the redistributor regions. As we already have code that does this,
> let's factor it out and make it slightly more generic.
>
> Signed-off-by: Marc Zyngier <marc.zyngier@xxxxxxx>
> ---
> drivers/irqchip/irq-gic-v3.c | 77 ++++++++++++++++++++++++++++++++------------
> 1 file changed, 56 insertions(+), 21 deletions(-)
>
> diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c
> index c132f29..5cadec0 100644
> --- a/drivers/irqchip/irq-gic-v3.c
> +++ b/drivers/irqchip/irq-gic-v3.c
> @@ -421,24 +421,15 @@ static void __init gic_dist_init(void)
> gic_write_irouter(affinity, base + GICD_IROUTER + i * 8);
> }
>
> -static int gic_populate_rdist(void)
> +static int gic_scan_rdist_properties(int (*fn)(struct redist_region *,
> + void __iomem *))
> {
> - unsigned long mpidr = cpu_logical_map(smp_processor_id());
> - u64 typer;
> - u32 aff;
> + int ret = 0;
in case
if (reg != GIC_PIDR2_ARCH_GICv3 &&
reg != GIC_PIDR2_ARCH_GICv4) is true you now return 0. Don' you
want to return -ENODEV as before?
> int i;
>
> - /*
> - * Convert affinity to a 32bit value that can be matched to
> - * GICR_TYPER bits [63:32].
> - */
> - aff = (MPIDR_AFFINITY_LEVEL(mpidr, 3) << 24 |
> - MPIDR_AFFINITY_LEVEL(mpidr, 2) << 16 |
> - MPIDR_AFFINITY_LEVEL(mpidr, 1) << 8 |
> - MPIDR_AFFINITY_LEVEL(mpidr, 0));
> -
> for (i = 0; i < gic_data.nr_redist_regions; i++) {
> void __iomem *ptr = gic_data.redist_regions[i].redist_base;
> + u64 typer;
> u32 reg;
>
> reg = readl_relaxed(ptr + GICR_PIDR2) & GIC_PIDR2_ARCH_MASK;
> @@ -450,14 +441,14 @@ static int gic_populate_rdist(void)
>
> do {
> typer = gic_read_typer(ptr + GICR_TYPER);
> - if ((typer >> 32) == aff) {
> - u64 offset = ptr - gic_data.redist_regions[i].redist_base;
> - gic_data_rdist_rd_base() = ptr;
> - gic_data_rdist()->phys_base = gic_data.redist_regions[i].phys_base + offset;
> - pr_info("CPU%d: found redistributor %lx region %d:%pa\n",
> - smp_processor_id(), mpidr, i,
> - &gic_data_rdist()->phys_base);
> + ret = fn(gic_data.redist_regions + i, ptr);
> + switch (ret) {
> + case 0:
> return 0;
> + case -1:
> + break;
> + default:
> + ret = 0;
> }
>
> if (gic_data.redist_regions[i].single_redist)
> @@ -473,9 +464,53 @@ static int gic_populate_rdist(void)
> } while (!(typer & GICR_TYPER_LAST));
> }
Assuming you don't find the TYPER that matches the cpu (I don't know if
it is possible), last fn() call will return 1 and the function will
return 0. Before it returned -ENODEV I think.
Thanks
Eric
>
> + if (ret == -1)
> + ret = -ENODEV;
> +
> + return 0;
> +}
> +
> +static int __gic_populate_rdist(struct redist_region *region, void __iomem *ptr)
> +{
> + unsigned long mpidr = cpu_logical_map(smp_processor_id());
> + u64 typer;
> + u32 aff;
> +
> + /*
> + * Convert affinity to a 32bit value that can be matched to
> + * GICR_TYPER bits [63:32].
> + */
> + aff = (MPIDR_AFFINITY_LEVEL(mpidr, 3) << 24 |
> + MPIDR_AFFINITY_LEVEL(mpidr, 2) << 16 |
> + MPIDR_AFFINITY_LEVEL(mpidr, 1) << 8 |
> + MPIDR_AFFINITY_LEVEL(mpidr, 0));
> +
> + typer = gic_read_typer(ptr + GICR_TYPER);
> + if ((typer >> 32) == aff) {
> + u64 offset = ptr - region->redist_base;
> + gic_data_rdist_rd_base() = ptr;
> + gic_data_rdist()->phys_base = region->phys_base + offset;
> +
> + pr_info("CPU%d: found redistributor %lx region %d:%pa\n",
> + smp_processor_id(), mpidr,
> + (int)(region - gic_data.redist_regions),
> + &gic_data_rdist()->phys_base);
> + return 0;
> + }
> +
> + /* Try next one */
> + return 1;
> +}
> +
> +static int gic_populate_rdist(void)
> +{
> + if (gic_scan_rdist_properties(__gic_populate_rdist) == 0)
> + return 0;
> +
> /* We couldn't even deal with ourselves... */
> WARN(true, "CPU%d: mpidr %lx has no re-distributor!\n",
> - smp_processor_id(), mpidr);
> + smp_processor_id(),
> + (unsigned long)cpu_logical_map(smp_processor_id()));
> return -ENODEV;
> }
>
>