The GIC distributor actually supports *two* enable bits, one per
interrupt group. Linux itself won't care and will only ever use one bit.
In a VM however we have two groups available, so we should be able to
flip the two separate enable bits.
Provide tests that try to flip the two available bits and check whether
they stick.
Signed-off-by: Andre Przywara <andre.przywara@xxxxxxx>
---
arm/gic.c | 21 +++++++++++++++++++++
lib/arm/asm/gic-v3.h | 4 ++--
lib/arm/gic-v3.c | 2 +-
3 files changed, 24 insertions(+), 3 deletions(-)
diff --git a/arm/gic.c b/arm/gic.c
index 485ca4f..a0511e5 100644
--- a/arm/gic.c
+++ b/arm/gic.c
@@ -640,6 +640,8 @@ static void spi_test_smp(void)
report("SPI delievered on all cores", cores == nr_cpus);
}
+#define GICD_CTLR_ENABLE_BOTH (GICD_CTLR_ENABLE_G0 | GICD_CTLR_ENABLE_G1)
+
/*
* Check the security state configuration of the GIC.
* Test whether we can switch to a single security state, to test both
@@ -694,6 +696,25 @@ static void test_irq_group(void *gicd_base)
return;
}
+ /* Check whether the group enable bits stick. */
+ reg = readl(gicd_base + GICD_CTLR);
+ writel(reg & ~GICD_CTLR_ENABLE_BOTH, gicd_base + GICD_CTLR);
+ reg = readl(gicd_base + GICD_CTLR);
+ report("both groups disabled sticks",
+ (reg & GICD_CTLR_ENABLE_BOTH) == 0);
+
+ reg &= ~GICD_CTLR_ENABLE_BOTH;
+ writel(reg | GICD_CTLR_ENABLE_G1, gicd_base + GICD_CTLR);
+ reg = readl(gicd_base + GICD_CTLR);
+ report("group 1 enabled sticks",
+ (reg & GICD_CTLR_ENABLE_BOTH) == GICD_CTLR_ENABLE_G1);
+
+ reg &= ~GICD_CTLR_ENABLE_BOTH;
+ writel(reg | GICD_CTLR_ENABLE_G0, gicd_base + GICD_CTLR);
+ reg = readl(gicd_base + GICD_CTLR);
+ report("group 0 enabled sticks",
+ (reg & GICD_CTLR_ENABLE_BOTH) == GICD_CTLR_ENABLE_G0);
+
/*
* On a security aware GIC in non-secure world the IGROUPR registers
* are RAZ/WI. KVM emulates a single-security-state GIC, so both
diff --git a/lib/arm/asm/gic-v3.h b/lib/arm/asm/gic-v3.h
index 2eaf944..0a29610 100644
--- a/lib/arm/asm/gic-v3.h
+++ b/lib/arm/asm/gic-v3.h
@@ -21,8 +21,8 @@
#define GICD_CTLR_RWP (1U << 31)
#define GICD_CTLR_DS (1U << 6)
#define GICD_CTLR_ARE_NS (1U << 4)
-#define GICD_CTLR_ENABLE_G1A (1U << 1)
-#define GICD_CTLR_ENABLE_G1 (1U << 0)
+#define GICD_CTLR_ENABLE_G1 (1U << 1)
+#define GICD_CTLR_ENABLE_G0 (1U << 0)
#define GICD_IROUTER 0x6000
#define GICD_PIDR2 0xffe8
diff --git a/lib/arm/gic-v3.c b/lib/arm/gic-v3.c
index feecb5e..d6a5186 100644
--- a/lib/arm/gic-v3.c
+++ b/lib/arm/gic-v3.c
@@ -42,7 +42,7 @@ void gicv3_enable_defaults(void)
writel(0, dist + GICD_CTLR);
gicv3_dist_wait_for_rwp();
- writel(GICD_CTLR_ARE_NS | GICD_CTLR_ENABLE_G1A | GICD_CTLR_ENABLE_G1,
+ writel(GICD_CTLR_ARE_NS | GICD_CTLR_ENABLE_G0 | GICD_CTLR_ENABLE_G1,
dist + GICD_CTLR);
gicv3_dist_wait_for_rwp();
--
2.17.1
