[PATCH v1 2/2] arch: arm: use dt and UCLASS_SYSCON to get gic lpi details

[Rayagonda Kokatanur]

Use device tree and UCLASS_SYSCON driver to get
Generic Interrupt Controller (GIC) lpi address and
maximum GIC redistributors count.

Also update Kconfig to select REGMAP and SYSCON when
GIC_V3_ITS is enabled.

Signed-off-by: Rayagonda Kokatanur <rayagonda.kokatanur at broadcom.com>
---
 arch/arm/Kconfig              |  2 ++
 arch/arm/include/asm/gic-v3.h |  4 +--
 arch/arm/lib/gic-v3-its.c     | 63 +++++++++++++++++++++++++++++++----
 3 files changed, 60 insertions(+), 9 deletions(-)

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index f115fcdcc4..2fd20fc648 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -64,6 +64,8 @@ endif
 
 config GIC_V3_ITS
 	bool "ARM GICV3 ITS"
+	select REGMAP
+	select SYSCON
 	help
 	  ARM GICV3 Interrupt translation service (ITS).
 	  Basic support for programming locality specific peripheral
diff --git a/arch/arm/include/asm/gic-v3.h b/arch/arm/include/asm/gic-v3.h
index 5131fabec4..35efec78c3 100644
--- a/arch/arm/include/asm/gic-v3.h
+++ b/arch/arm/include/asm/gic-v3.h
@@ -127,9 +127,9 @@
 #define GIC_REDISTRIBUTOR_OFFSET 0x20000
 
 #ifdef CONFIG_GIC_V3_ITS
-int gic_lpi_tables_init(u64 base, u32 max_redist);
+int gic_lpi_tables_init(void);
 #else
-int gic_lpi_tables_init(u64 base, u32 max_redist)
+int gic_lpi_tables_init(void)
 {
 	return 0;
 }
diff --git a/arch/arm/lib/gic-v3-its.c b/arch/arm/lib/gic-v3-its.c
index 7c4e5f4d07..d723048a66 100644
--- a/arch/arm/lib/gic-v3-its.c
+++ b/arch/arm/lib/gic-v3-its.c
@@ -4,6 +4,8 @@
  */
 #include <common.h>
 #include <dm.h>
+#include <regmap.h>
+#include <syscon.h>
 #include <asm/gic.h>
 #include <asm/gic-v3.h>
 #include <asm/io.h>
@@ -16,15 +18,22 @@ static u32 lpi_id_bits;
 #define LPI_PROPBASE_SZ		ALIGN(BIT(LPI_NRBITS), SZ_64K)
 #define LPI_PENDBASE_SZ		ALIGN(BIT(LPI_NRBITS) / 8, SZ_64K)
 
+/* Number of GIC re-distributors */
+#define MAX_GIC_REDISTRIBUTORS	8
+
 /*
  * gic_v3_its_priv - gic details
  *
  * @gicd_base: gicd base address
  * @gicr_base: gicr base address
+ * @lpi_base: gic lpi base address
+ * @num_redist: number of gic re-distributors
  */
 struct gic_v3_its_priv {
 	u32 gicd_base;
 	u32 gicr_base;
+	u32 lpi_base;
+	u32 num_redist;
 };
 
 static int gic_v3_its_get_gic_addr(struct gic_v3_its_priv *priv)
@@ -58,13 +67,39 @@ static int gic_v3_its_get_gic_addr(struct gic_v3_its_priv *priv)
 	return 0;
 }
 
+static int gic_v3_its_get_gic_lpi_addr(struct gic_v3_its_priv *priv)
+{
+	struct regmap *regmap;
+	struct udevice *dev;
+	int ret;
+
+	ret = uclass_get_device_by_driver(UCLASS_SYSCON,
+					  DM_GET_DRIVER(gic_lpi_syscon), &dev);
+	if (ret) {
+		pr_err("%s: failed to get %s syscon device\n", __func__,
+		       DM_GET_DRIVER(gic_lpi_syscon)->name);
+		return ret;
+	}
+
+	regmap = syscon_get_regmap(dev);
+	if (!regmap) {
+		pr_err("%s: failed to regmap for %s syscon device\n", __func__,
+		       DM_GET_DRIVER(gic_lpi_syscon)->name);
+		return -ENODEV;
+	}
+	priv->lpi_base = regmap->ranges[0].start;
+
+	priv->num_redist = dev_read_u32_default(dev, "max-gic-redistributors",
+						MAX_GIC_REDISTRIBUTORS);
+
+	return 0;
+}
+
 /*
  * 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)
+int gic_lpi_tables_init(void)
 {
 	struct gic_v3_its_priv priv;
 	u32 gicd_typer;
@@ -77,6 +112,9 @@ int gic_lpi_tables_init(u64 base, u32 num_redist)
 	if (gic_v3_its_get_gic_addr(&priv))
 		return -EINVAL;
 
+	if (gic_v3_its_get_gic_lpi_addr(&priv))
+		return -EINVAL;
+
 	gicd_typer = readl(priv.gicd_base + GICD_TYPER);
 	/* GIC support for Locality specific peripheral interrupts (LPI's) */
 	if (!(gicd_typer & GICD_TYPER_LPIS)) {
@@ -89,7 +127,7 @@ int gic_lpi_tables_init(u64 base, u32 num_redist)
 	 * 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++) {
+	for (i = 0; i < priv.num_redist; i++) {
 		u32 offset = i * GIC_REDISTRIBUTOR_OFFSET;
 
 		if ((readl((uintptr_t)(priv.gicr_base + offset))) &
@@ -105,7 +143,7 @@ int gic_lpi_tables_init(u64 base, u32 num_redist)
 			    ITS_MAX_LPI_NRBITS);
 
 	/* Set PropBase */
-	val = (base |
+	val = (priv.lpi_base |
 	       GICR_PROPBASER_INNERSHAREABLE |
 	       GICR_PROPBASER_RAWAWB |
 	       ((LPI_NRBITS - 1) & GICR_PROPBASER_IDBITS_MASK));
@@ -121,10 +159,10 @@ int gic_lpi_tables_init(u64 base, u32 num_redist)
 		}
 	}
 
-	redist_lpi_base = base + LPI_PROPBASE_SZ;
+	redist_lpi_base = priv.lpi_base + LPI_PROPBASE_SZ;
 
 	pend_base = priv.gicr_base + GICR_PENDBASER;
-	for (i = 0; i < num_redist; i++) {
+	for (i = 0; i < priv.num_redist; i++) {
 		u32 offset = i * GIC_REDISTRIBUTOR_OFFSET;
 
 		val = ((redist_lpi_base + (i * LPI_PENDBASE_SZ)) |
@@ -158,3 +196,14 @@ U_BOOT_DRIVER(arm_gic_v3_its) = {
 	.id		= UCLASS_IRQ,
 	.of_match	= gic_v3_its_ids,
 };
+
+static const struct udevice_id gic_lpi_syscon_ids[] = {
+	{ .compatible = "gic-lpi-base" },
+	{}
+};
+
+U_BOOT_DRIVER(gic_lpi_syscon) = {
+	.name		= "gic-lpi-base",
+	.id		= UCLASS_SYSCON,
+	.of_match	= gic_lpi_syscon_ids,
+};
-- 
2.17.1