[V7,09/13] boot_constraint: Add support for Hisilicon platforms

diff --git a/drivers/soc/Kconfig b/drivers/soc/Kconfig
index c07b4a85253f..7fd6d59f15bd 100644
--- a/drivers/soc/Kconfig
+++ b/drivers/soc/Kconfig
@@ -5,6 +5,7 @@  source "drivers/soc/amlogic/Kconfig"
 source "drivers/soc/atmel/Kconfig"
 source "drivers/soc/bcm/Kconfig"
 source "drivers/soc/fsl/Kconfig"
+source "drivers/soc/hisilicon/Kconfig"
 source "drivers/soc/imx/Kconfig"
 source "drivers/soc/mediatek/Kconfig"
 source "drivers/soc/qcom/Kconfig"
diff --git a/drivers/soc/Makefile b/drivers/soc/Makefile
index 40523577bdaa..2daf7c1a52ee 100644
--- a/drivers/soc/Makefile
+++ b/drivers/soc/Makefile
@@ -10,6 +10,7 @@  obj-$(CONFIG_ARCH_DOVE)		+= dove/
 obj-$(CONFIG_MACH_DOVE)		+= dove/
 obj-y				+= fsl/
 obj-$(CONFIG_ARCH_GEMINI)	+= gemini/
+obj-$(CONFIG_ARCH_HISI)		+= hisilicon/
 obj-$(CONFIG_ARCH_MXC)		+= imx/
 obj-$(CONFIG_SOC_XWAY)		+= lantiq/
 obj-y				+= mediatek/
diff --git a/drivers/soc/hisilicon/Kconfig b/drivers/soc/hisilicon/Kconfig
new file mode 100644
index 000000000000..7247b13a60a2
--- /dev/null
+++ b/drivers/soc/hisilicon/Kconfig
@@ -0,0 +1,15 @@ 
+#
+# Hisilicon Soc drivers
+#
+
+menu "Hisilicon SoC drivers"
+
+config HISI_BOOT_CONSTRAINT
+	bool "Hisilicon Boot Constraints"
+	depends on ARCH_HISI
+	select DEV_BOOT_CONSTRAINT
+	default y
+	help
+	  Say y here to enable Boot Constraints on Hisilicon platforms.
+
+endmenu
diff --git a/drivers/soc/hisilicon/Makefile b/drivers/soc/hisilicon/Makefile
new file mode 100644
index 000000000000..c63cb9b17bed
--- /dev/null
+++ b/drivers/soc/hisilicon/Makefile
@@ -0,0 +1,3 @@ 
+# SPDX-License-Identifier: GPL-2.0
+
+obj-$(CONFIG_HISI_BOOT_CONSTRAINT) += boot_constraint.o
diff --git a/drivers/soc/hisilicon/boot_constraint.c b/drivers/soc/hisilicon/boot_constraint.c
new file mode 100644
index 000000000000..fa0b25d6ab8e
--- /dev/null
+++ b/drivers/soc/hisilicon/boot_constraint.c
@@ -0,0 +1,158 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * This takes care of Hisilicon boot time device constraints, normally set by
+ * the Bootloader.
+ *
+ * Copyright (c) 2018 Linaro.
+ * Viresh Kumar <viresh.kumar@linaro.org>
+ */
+
+#include <linux/boot_constraint.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/of.h>
+
+static bool earlycon_boot_constraints_enabled __initdata;
+
+static int __init enable_earlycon_boot_constraints(char *str)
+{
+	earlycon_boot_constraints_enabled = true;
+
+	return 0;
+}
+
+__setup_param("earlycon", boot_constraint_earlycon,
+	      enable_earlycon_boot_constraints, 0);
+__setup_param("earlyprintk", boot_constraint_earlyprintk,
+	      enable_earlycon_boot_constraints, 0);
+
+
+struct hikey_machine_constraints {
+	struct dev_boot_constraint_of *dev_constraints;
+	unsigned int count;
+};
+
+static struct dev_boot_constraint_clk_info uart_iclk_info = {
+	.name = "uartclk",
+};
+
+static struct dev_boot_constraint_clk_info uart_pclk_info = {
+	.name = "apb_pclk",
+};
+
+static struct dev_boot_constraint hikey3660_uart_constraints[] = {
+	{
+		.type = DEV_BOOT_CONSTRAINT_CLK,
+		.data = &uart_iclk_info,
+	}, {
+		.type = DEV_BOOT_CONSTRAINT_CLK,
+		.data = &uart_pclk_info,
+	},
+};
+
+static const char * const uarts_hikey3660[] = {
+	"serial@fff32000",	/* UART 6 */
+};
+
+static struct dev_boot_constraint_of hikey3660_dev_constraints[] = {
+	{
+		.compat = "arm,pl011",
+		.constraints = hikey3660_uart_constraints,
+		.count = ARRAY_SIZE(hikey3660_uart_constraints),
+
+		.dev_names = uarts_hikey3660,
+		.dev_names_count = ARRAY_SIZE(uarts_hikey3660),
+	},
+};
+
+static struct hikey_machine_constraints hikey3660_constraints = {
+	.dev_constraints = hikey3660_dev_constraints,
+	.count = ARRAY_SIZE(hikey3660_dev_constraints),
+};
+
+static const char * const uarts_hikey6220[] = {
+	"uart@f7113000",	/* UART 3 */
+};
+
+static struct dev_boot_constraint_of hikey6220_dev_constraints[] = {
+	{
+		.compat = "arm,pl011",
+		.constraints = hikey3660_uart_constraints,
+		.count = ARRAY_SIZE(hikey3660_uart_constraints),
+
+		.dev_names = uarts_hikey6220,
+		.dev_names_count = ARRAY_SIZE(uarts_hikey6220),
+	},
+};
+
+static struct hikey_machine_constraints hikey6220_constraints = {
+	.dev_constraints = hikey6220_dev_constraints,
+	.count = ARRAY_SIZE(hikey6220_dev_constraints),
+};
+
+static struct dev_boot_constraint hikey3798cv200_uart_constraints[] = {
+	{
+		.type = DEV_BOOT_CONSTRAINT_CLK,
+		.data = &uart_pclk_info,
+	},
+};
+
+static const char * const uarts_hikey3798cv200[] = {
+	"serial@8b00000",	/* UART 0 */
+};
+
+static struct dev_boot_constraint_of hikey3798cv200_dev_constraints[] = {
+	{
+		.compat = "arm,pl011",
+		.constraints = hikey3798cv200_uart_constraints,
+		.count = ARRAY_SIZE(hikey3798cv200_uart_constraints),
+
+		.dev_names = uarts_hikey3798cv200,
+		.dev_names_count = ARRAY_SIZE(uarts_hikey3798cv200),
+	},
+};
+
+static struct hikey_machine_constraints hikey3798cv200_constraints = {
+	.dev_constraints = hikey3798cv200_dev_constraints,
+	.count = ARRAY_SIZE(hikey3798cv200_dev_constraints),
+};
+
+static const struct of_device_id machines[] __initconst = {
+	{ .compatible = "hisilicon,hi3660", .data = &hikey3660_constraints },
+	{ .compatible = "hisilicon,hi3798cv200", .data = &hikey3798cv200_constraints },
+	{ .compatible = "hisilicon,hi6220", .data = &hikey6220_constraints },
+	{ }
+};
+
+static int __init hikey_constraints_init(void)
+{
+	const struct hikey_machine_constraints *constraints;
+	const struct of_device_id *match;
+	struct device_node *np;
+
+	if (!earlycon_boot_constraints_enabled)
+		return 0;
+
+	np = of_find_node_by_path("/");
+	if (!np)
+		return -ENODEV;
+
+	match = of_match_node(machines, np);
+	of_node_put(np);
+
+	if (!match)
+		return 0;
+
+	constraints = match->data;
+
+	dev_boot_constraint_add_deferrable_of(constraints->dev_constraints,
+					      constraints->count);
+
+	return 0;
+}
+
+/*
+ * The amba-pl011 driver registers itself from arch_initcall level. Setup the
+ * serial boot constraints before that in order not to miss any boot messages.
+ */
+postcore_initcall_sync(hikey_constraints_init);