arm64: Add hypervisor safe helper for checking constant capabilities

The hypervisor may not have full access to the kernel data structures
and hence cannot safely use cpus_have_cap() helper for checking the
system capability. Add a safe helper for hypervisors to check a constant
system capability, which *doesn't* fall back to checking the bitmap
maintained by the kernel. With this, make the cpus_have_cap() only
check the bitmask and force constant cap checks to use the new API
for quicker checks.

Cc: Robert Ritcher <rritcher@cavium.com>
Cc: Tirumalesh Chalamarla <tchalamarla@cavium.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
This commit is contained in:
Suzuki K Poulose
2016-11-08 13:56:20 +00:00
committed by Catalin Marinas
parent c02433dd6d
commit a4023f6827
4 changed files with 15 additions and 21 deletions

View File

@@ -120,11 +120,10 @@ static void gic_redist_wait_for_rwp(void)
}
#ifdef CONFIG_ARM64
static DEFINE_STATIC_KEY_FALSE(is_cavium_thunderx);
static u64 __maybe_unused gic_read_iar(void)
{
if (static_branch_unlikely(&is_cavium_thunderx))
if (cpus_have_const_cap(ARM64_WORKAROUND_CAVIUM_23154))
return gic_read_iar_cavium_thunderx();
else
return gic_read_iar_common();
@@ -905,14 +904,6 @@ static const struct irq_domain_ops partition_domain_ops = {
.select = gic_irq_domain_select,
};
static void gicv3_enable_quirks(void)
{
#ifdef CONFIG_ARM64
if (cpus_have_cap(ARM64_WORKAROUND_CAVIUM_23154))
static_branch_enable(&is_cavium_thunderx);
#endif
}
static int __init gic_init_bases(void __iomem *dist_base,
struct redist_region *rdist_regs,
u32 nr_redist_regions,
@@ -935,8 +926,6 @@ static int __init gic_init_bases(void __iomem *dist_base,
gic_data.nr_redist_regions = nr_redist_regions;
gic_data.redist_stride = redist_stride;
gicv3_enable_quirks();
/*
* Find out how many interrupts are supported.
* The GIC only supports up to 1020 interrupt sources (SGI+PPI+SPI)