arch: arm: Program GIC LPI configuration table

Programs the following:
1. Redistributor PROCBASER configuration table (which
is common for all redistributors)
2. Redistributor pending table (PENDBASER), for all the
available redistributors.

Signed-off-by: Bharat Kumar Reddy Gooty <bharat.gooty@broadcom.com>
Signed-off-by: Vladimir Olovyannikov <vladimir.olovyannikov@broadcom.com>

2 files changed, 101 insertions, 0 deletions

diff --git a/arch/arm/lib/Makefile b/arch/arm/lib/Makefile
index 9de9a9acee..8482f5446c 100644
--- a/arch/arm/lib/Makefile
+++ b/arch/arm/lib/Makefile
@@ -52,6 +52,7 @@ obj-$(CONFIG_FSL_LAYERSCAPE) += ccn504.o
 ifneq ($(CONFIG_GICV2)$(CONFIG_GICV3),)
 obj-y	+= gic_64.o
 endif
+obj-$(CONFIG_GIC_V3_ITS)	+= gic-v3-its.o
 obj-y	+= interrupts_64.o
 else
 obj-y	+= interrupts.o
diff --git a/arch/arm/lib/gic-v3-its.c b/arch/arm/lib/gic-v3-its.c
new file mode 100644
index 0000000000..e19ab01621
--- /dev/null
+++ b/arch/arm/lib/gic-v3-its.c
@@ -0,0 +1,100 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright 2019 Broadcom.
+ */
+#include <common.h>
+#include <asm/gic.h>
+#include <asm/gic-v3.h>
+#include <asm/io.h>
+
+static u32 lpi_id_bits;
+
+#define LPI_NRBITS		lpi_id_bits
+#define LPI_PROPBASE_SZ		ALIGN(BIT(LPI_NRBITS), SZ_64K)
+#define LPI_PENDBASE_SZ		ALIGN(BIT(LPI_NRBITS) / 8, SZ_64K)
+
+/*
+ * Program the GIC LPI configuration tables for all
+ * the re-distributors and enable the LPI table
+ * base: Configuration table address
+ * num_redist: number of redistributors
+ */
+int gic_lpi_tables_init(u64 base, u32 num_redist)
+{
+	u32 gicd_typer;
+	u64 val;
+	u64 tmp;
+	int i;
+	u64 redist_lpi_base;
+	u64 pend_base = GICR_BASE + GICR_PENDBASER;
+
+	gicd_typer = readl(GICD_BASE + GICD_TYPER);
+
+	/* GIC support for Locality specific peripheral interrupts (LPI's) */
+	if (!(gicd_typer & GICD_TYPER_LPIS)) {
+		pr_err("GIC implementation does not support LPI's\n");
+		return -EINVAL;
+	}
+
+	/*
+	 * Check for LPI is disabled for all the redistributors.
+	 * Once the LPI table is enabled, can not program the
+	 * LPI configuration tables again, unless the GIC is reset.
+	 */
+	for (i = 0; i < num_redist; i++) {
+		u32 offset = i * GIC_REDISTRIBUTOR_OFFSET;
+
+		if ((readl((uintptr_t)(GICR_BASE + offset))) &
+		    GICR_CTLR_ENABLE_LPIS) {
+			pr_err("Re-Distributor %d LPI is already enabled\n",
+			       i);
+			return -EINVAL;
+		}
+	}
+
+	/* lpi_id_bits to get LPI_PENDBASE_SZ and LPi_PROPBASE_SZ */
+	lpi_id_bits = min_t(u32, GICD_TYPER_ID_BITS(gicd_typer),
+			    ITS_MAX_LPI_NRBITS);
+
+	/* Set PropBase */
+	val = (base |
+	       GICR_PROPBASER_INNERSHAREABLE |
+	       GICR_PROPBASER_RAWAWB |
+	       ((LPI_NRBITS - 1) & GICR_PROPBASER_IDBITS_MASK));
+
+	writeq(val, (GICR_BASE + GICR_PROPBASER));
+	tmp = readl(GICR_BASE + GICR_PROPBASER);
+	if ((tmp ^ val) & GICR_PROPBASER_SHAREABILITY_MASK) {
+		if (!(tmp & GICR_PROPBASER_SHAREABILITY_MASK)) {
+			val &= ~(GICR_PROPBASER_SHAREABILITY_MASK |
+				GICR_PROPBASER_CACHEABILITY_MASK);
+			val |= GICR_PROPBASER_NC;
+			writeq(val, (GICR_BASE + GICR_PROPBASER));
+		}
+	}
+
+	redist_lpi_base = base + LPI_PROPBASE_SZ;
+
+	for (i = 0; i < num_redist; i++) {
+		u32 offset = i * GIC_REDISTRIBUTOR_OFFSET;
+
+		val = ((redist_lpi_base + (i * LPI_PENDBASE_SZ)) |
+			GICR_PENDBASER_INNERSHAREABLE |
+			GICR_PENDBASER_RAWAWB);
+
+		writeq(val, (uintptr_t)(pend_base + offset));
+		tmp = readq((uintptr_t)(pend_base + offset));
+		if (!(tmp & GICR_PENDBASER_SHAREABILITY_MASK)) {
+			val &= ~(GICR_PENDBASER_SHAREABILITY_MASK |
+				 GICR_PENDBASER_CACHEABILITY_MASK);
+			val |= GICR_PENDBASER_NC;
+			writeq(val, (uintptr_t)(pend_base + offset));
+		}
+
+		/* Enable LPI for the redistributor */
+		writel(GICR_CTLR_ENABLE_LPIS, (uintptr_t)(GICR_BASE + offset));
+	}
+
+	return 0;
+}
+