[PATCH 1/1] arch: arm: Program GIC LPI configuration table

[Vladimir Olovyannikov <vladimir.olovyannikov@broadcom.com>]

From: Bharat Kumar Reddy Gooty <bharat.gooty@broadcom.com>

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>
---
 arch/arm/Kconfig              |  11 +++
 arch/arm/include/asm/gic-v3.h | 134 ++++++++++++++++++++++++++++++++++
 arch/arm/lib/Makefile         |   3 +
 arch/arm/lib/gic-v3-its.c     | 100 +++++++++++++++++++++++++
 4 files changed, 248 insertions(+)
 create mode 100644 arch/arm/include/asm/gic-v3.h
 create mode 100644 arch/arm/lib/gic-v3-its.c

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index f96841c777..cf46aa867d 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -61,6 +61,17 @@ config LNX_KRNL_IMG_TEXT_OFFSET_BASE
 endif
 endif
 
+config GIC_V3_ITS
+	bool "ARM GICV3 ITS"
+	default n
+	help
+	  ARM GICV3 Interrupt translation service (ITS).
+	  Basic support for programming locality specific peripheral
+	  interrupts (LPI) configuration tables and enable LPI tables.
+	  LPI configuration table can be used by u-boot or Linux.
+	  ARM GICV3 has limitation, once the LPI table is enabled, LPI
+	  configuration table can not be re-programmed, unless GICV3 reset.
+
 config STATIC_RELA
 	bool
 	default y if ARM64 && !POSITION_INDEPENDENT
diff --git a/arch/arm/include/asm/gic-v3.h b/arch/arm/include/asm/gic-v3.h
new file mode 100644
index 0000000000..ac6c9e7013
--- /dev/null
+++ b/arch/arm/include/asm/gic-v3.h
@@ -0,0 +1,134 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright 2019 Broadcom.
+ */
+
+#ifndef __GIC_V3_H__
+#define __GIC_V3_H__
+
+#define GICR_CTLR_ENABLE_LPIS		BIT(0)
+#define GICR_CTLR_RWP			BIT(3)
+
+#define GICR_TYPER_CPU_NUMBER(r)	(((r) >> 8) & 0xffff)
+
+#define GICR_WAKER_PROCESSORSLEEP	BIT(1)
+#define GICR_WAKER_CHILDRENASLEEP	BIT(2)
+
+#define GIC_BASER_CACHE_NCNB		0ULL
+#define GIC_BASER_CACHE_SAMEASINNER	0ULL
+#define GIC_BASER_CACHE_NC		1ULL
+#define GIC_BASER_CACHE_RAWT		2ULL
+#define GIC_BASER_CACHE_RAWB		3ULL
+#define GIC_BASER_CACHE_WAWT		4ULL
+#define GIC_BASER_CACHE_WAWB		5ULL
+#define GIC_BASER_CACHE_RAWAWT		6ULL
+#define GIC_BASER_CACHE_RAWAWB		7ULL
+#define GIC_BASER_CACHE_MASK		7ULL
+#define GIC_BASER_NONSHAREABLE		0ULL
+#define GIC_BASER_INNERSHAREABLE	1ULL
+#define GIC_BASER_OUTERSHAREABLE	2ULL
+#define GIC_BASER_SHAREABILITY_MASK	3ULL
+
+#define GIC_BASER_CACHEABILITY(reg, inner_outer, type)	\
+	(GIC_BASER_CACHE_##type << reg##_##inner_outer##_CACHEABILITY_SHIFT)
+
+#define GIC_BASER_SHAREABILITY(reg, type)	\
+	(GIC_BASER_##type << reg##_SHAREABILITY_SHIFT)
+
+/* encode a size field of width @w containing @n - 1 units */
+#define GIC_ENCODE_SZ(n, w) (((unsigned long)(n) - 1) &\
+			     GENMASK_ULL(((w) - 1), 0))
+
+#define GICR_PROPBASER_SHAREABILITY_SHIFT		(10)
+#define GICR_PROPBASER_INNER_CACHEABILITY_SHIFT		(7)
+#define GICR_PROPBASER_OUTER_CACHEABILITY_SHIFT		(56)
+#define GICR_PROPBASER_SHAREABILITY_MASK	\
+	GIC_BASER_SHAREABILITY(GICR_PROPBASER, SHAREABILITY_MASK)
+#define GICR_PROPBASER_INNER_CACHEABILITY_MASK	\
+	GIC_BASER_CACHEABILITY(GICR_PROPBASER, INNER, MASK)
+#define GICR_PROPBASER_OUTER_CACHEABILITY_MASK	\
+	GIC_BASER_CACHEABILITY(GICR_PROPBASER, OUTER, MASK)
+#define GICR_PROPBASER_CACHEABILITY_MASK GICR_PROPBASER_INNER_CACHEABILITY_MASK
+
+#define GICR_PROPBASER_INNERSHAREABLE	\
+	GIC_BASER_SHAREABILITY(GICR_PROPBASER, INNERSHAREABLE)
+
+#define GICR_PROPBASER_NCNB	\
+	GIC_BASER_CACHEABILITY(GICR_PROPBASER, INNER, NCNB)
+#define GICR_PROPBASER_NC	\
+	GIC_BASER_CACHEABILITY(GICR_PROPBASER, INNER, NC)
+#define GICR_PROPBASER_RAWT	\
+	GIC_BASER_CACHEABILITY(GICR_PROPBASER, INNER, RAWT)
+#define GICR_PROPBASER_RAWB	\
+	GIC_BASER_CACHEABILITY(GICR_PROPBASER, INNER, RAWB)
+#define GICR_PROPBASER_WAWT	\
+	GIC_BASER_CACHEABILITY(GICR_PROPBASER, INNER, WAWT)
+#define GICR_PROPBASER_WAWB	\
+	GIC_BASER_CACHEABILITY(GICR_PROPBASER, INNER, WAWB)
+#define GICR_PROPBASER_RAWAWT	\
+	GIC_BASER_CACHEABILITY(GICR_PROPBASER, INNER, RAWAWT)
+#define GICR_PROPBASER_RAWAWB	\
+	GIC_BASER_CACHEABILITY(GICR_PROPBASER, INNER, RAWAWB)
+
+#define GICR_PROPBASER_IDBITS_MASK	(0x1f)
+#define GICR_PROPBASER_ADDRESS(x)	((x) & GENMASK_ULL(51, 12))
+#define GICR_PENDBASER_ADDRESS(x)	((x) & GENMASK_ULL(51, 16))
+
+#define GICR_PENDBASER_SHAREABILITY_SHIFT		(10)
+#define GICR_PENDBASER_INNER_CACHEABILITY_SHIFT		(7)
+#define GICR_PENDBASER_OUTER_CACHEABILITY_SHIFT		(56)
+#define GICR_PENDBASER_SHAREABILITY_MASK	\
+	GIC_BASER_SHAREABILITY(GICR_PENDBASER, SHAREABILITY_MASK)
+#define GICR_PENDBASER_INNER_CACHEABILITY_MASK	\
+	GIC_BASER_CACHEABILITY(GICR_PENDBASER, INNER, MASK)
+#define GICR_PENDBASER_OUTER_CACHEABILITY_MASK	\
+	GIC_BASER_CACHEABILITY(GICR_PENDBASER, OUTER, MASK)
+#define GICR_PENDBASER_CACHEABILITY_MASK	\
+	GICR_PENDBASER_INNER_CACHEABILITY_MASK
+
+#define GICR_PENDBASER_INNERSHAREABLE	\
+	GIC_BASER_SHAREABILITY(GICR_PENDBASER, INNERSHAREABLE)
+
+#define GICR_PENDBASER_NCNB	\
+	GIC_BASER_CACHEABILITY(GICR_PENDBASER, INNER, NCNB)
+#define GICR_PENDBASER_NC	\
+	GIC_BASER_CACHEABILITY(GICR_PENDBASER, INNER, NC)
+#define GICR_PENDBASER_RAWT	\
+	GIC_BASER_CACHEABILITY(GICR_PENDBASER, INNER, RAWT)
+#define GICR_PENDBASER_RAWB	\
+	GIC_BASER_CACHEABILITY(GICR_PENDBASER, INNER, RAWB)
+#define GICR_PENDBASER_WAWT	\
+	GIC_BASER_CACHEABILITY(GICR_PENDBASER, INNER, WAWT)
+#define GICR_PENDBASER_WAWB	\
+	GIC_BASER_CACHEABILITY(GICR_PENDBASER, INNER, WAWB)
+#define GICR_PENDBASER_RAWAWT	\
+	GIC_BASER_CACHEABILITY(GICR_PENDBASER, INNER, RAWAWT)
+#define GICR_PENDBASER_RAWAWB	\
+	GIC_BASER_CACHEABILITY(GICR_PENDBASER, INNER, RAWAWB)
+
+#define GICR_PENDBASER_PTZ	BIT_ULL(62)
+
+#define ITS_MAX_LPI_NRBITS	16 /* 64K LPIs */
+
+#define GICD_TYPER_ID_BITS(typer)	((((typer) >> 19) & 0x1f) + 1)
+#define GICD_TYPER_NUM_LPIS(typer)	((((typer) >> 11) & 0x1f) + 1)
+#define GICD_TYPER_IRQS(typer)		((((typer) & 0x1f) + 1) * 32)
+
+/* Message based interrupts support */
+#define GICD_TYPER_MBIS		BIT(16)
+/* LPI support */
+#define GICD_TYPER_LPIS		BIT(17)
+#define GICD_TYPER_RSS		BIT(26)
+
+#define GIC_REDISTRIBUTOR_OFFSET 0x20000
+
+#ifdef CONFIG_GIC_V3_ITS
+int gic_lpi_tables_init(u64 base, u32 max_redist);
+#else
+int gic_lpi_tables_init(u64 base, u32 max_redist)
+{
+	return 0;
+}
+#endif /* CONFIG_GIC_V3_ITS */
+
+#endif /* __GIC_V3_H__ */
diff --git a/arch/arm/lib/Makefile b/arch/arm/lib/Makefile
index 9de9a9acee..942ed1c73a 100644
--- a/arch/arm/lib/Makefile
+++ b/arch/arm/lib/Makefile
@@ -52,6 +52,9 @@ obj-$(CONFIG_FSL_LAYERSCAPE) += ccn504.o
 ifneq ($(CONFIG_GICV2)$(CONFIG_GICV3),)
 obj-y	+= gic_64.o
 endif
+ifdef CONFIG_GIC_V3_ITS
+obj-y	+= gic-v3-its.o
+endif
 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;
+}
+
-- 
2.17.1