Starting with the A11 (T8015) SoC, Apple began using arm64 sysregs for
fast IPIs. However, on A11, there is no such things as "Local" fast IPIs,
as the SYS_IMP_APL_IPI_RR_LOCAL_EL1 register does not seem to exist.
Add a new feature level, used by the compatible "apple,t8015-aic",
controlled by a static branch key named use_local_fast_ipi. When
use_fast_ipi is true and use_local_fast_ipi is false, fast IPIs are used
but all IPIs goes through the register SYS_IMP_APL_IPI_RR_GLOBAL_EL1, as
"global" IPIs.
Signed-off-by: Nick Chan <towinchenmi@xxxxxxxxx>
---
drivers/irqchip/irq-apple-aic.c | 25 ++++++++++++++++++++++++-
1 file changed, 24 insertions(+), 1 deletion(-)
diff --git a/drivers/irqchip/irq-apple-aic.c b/drivers/irqchip/irq-apple-aic.c
index 626aaeafa96c..1640074af2e1 100644
--- a/drivers/irqchip/irq-apple-aic.c
+++ b/drivers/irqchip/irq-apple-aic.c
@@ -236,6 +236,8 @@ enum fiq_hwirq {
/* True if UNCORE/UNCORE2 and Sn_... IPI registers are present and used (A11+) */
static DEFINE_STATIC_KEY_TRUE(use_fast_ipi);
+/* True if SYS_IMP_APL_IPI_RR_LOCAL_EL1 exists (M1+) */
+static DEFINE_STATIC_KEY_TRUE(use_local_fast_ipi);
struct aic_info {
int version;
@@ -253,6 +255,7 @@ struct aic_info {
/* Features */
bool fast_ipi;
+ bool local_fast_ipi;
};
static const struct aic_info aic1_info __initconst = {
@@ -271,6 +274,16 @@ static const struct aic_info aic1_fipi_info __initconst = {
.fast_ipi = true,
};
+static const struct aic_info aic1_local_fipi_info __initconst = {
+ .version = 1,
+
+ .event = AIC_EVENT,
+ .target_cpu = AIC_TARGET_CPU,
+
+ .fast_ipi = true,
+ .local_fast_ipi = true,
+};
+
static const struct aic_info aic2_info __initconst = {
.version = 2,
@@ -282,6 +295,10 @@ static const struct aic_info aic2_info __initconst = {
static const struct of_device_id aic_info_match[] = {
{
.compatible = "apple,t8103-aic",
+ .data = &aic1_local_fipi_info,
+ },
+ {
+ .compatible = "apple,t8015-aic",
.data = &aic1_fipi_info,
},
{
@@ -748,7 +765,8 @@ static void aic_ipi_send_fast(int cpu)
u64 cluster = MPIDR_CLUSTER(mpidr);
u64 idx = MPIDR_CPU(mpidr);
- if (MPIDR_CLUSTER(my_mpidr) == cluster)
+ if (static_branch_likely(&use_local_fast_ipi) &&
+ MPIDR_CLUSTER(my_mpidr) == cluster)
write_sysreg_s(FIELD_PREP(IPI_RR_CPU, idx),
SYS_IMP_APL_IPI_RR_LOCAL_EL1);
else
@@ -992,6 +1010,11 @@ static int __init aic_of_ic_init(struct device_node *node, struct device_node *p
else
static_branch_disable(&use_fast_ipi);
+ if (irqc->info.local_fast_ipi)
+ static_branch_enable(&use_local_fast_ipi);
+ else
+ static_branch_disable(&use_local_fast_ipi);
+
irqc->info.die_stride = off - start_off;
irqc->hw_domain = irq_domain_create_tree(of_node_to_fwnode(node),
--
2.46.0
