soc: xilinx: zynqmp: Add soc_xilinx_zynqmp driver

soc_xilinx_zynqmp driver allows identification of family & revision
of zynqmp SoC. This driver is selected by CONFIG_SOC_XILINX_ZYNQMP.
Add this config to xilinx_zynqmp_virt_defconfig file.
Probe this driver using platdata U_BOOT_DEVICE structure which is
specified in mach-zynqmp/cpu.c.

Signed-off-by: T Karthik Reddy <t.karthik.reddy@xilinx.com>
Reviewed-by: Ashok Reddy Soma <ashok.reddy.soma@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>

MAINTAINERS

@@ -602,6 +602,7 @@ F:	drivers/net/zynq_gem.c
 F:	drivers/serial/serial_zynq.c
 F:	drivers/reset/reset-zynqmp.c
 F:	drivers/rtc/zynqmp_rtc.c
+F:	drivers/soc/soc_xilinx_zynqmp.c
 F:	drivers/spi/zynq_qspi.c
 F:	drivers/spi/zynq_spi.c
 F:	drivers/timer/cadence-ttc.c

arch/arm/Kconfig

@@ -1133,6 +1133,7 @@ config ARCH_ZYNQMP
 	select SPL_SEPARATE_BSS if SPL
 	select SUPPORT_SPL
 	select ZYNQMP_IPI
+	select SOC_DEVICE
 	imply BOARD_LATE_INIT
 	imply CMD_DM
 	imply ENV_VARS_UBOOT_RUNTIME_CONFIG

arch/arm/mach-zynqmp/cpu.c

@@ -15,6 +15,7 @@
 #include <asm/io.h>
 #include <zynqmp_firmware.h>
 #include <asm/cache.h>
+#include <dm/platdata.h>
 
 #define ZYNQ_SILICON_VER_MASK	0xF000
 #define ZYNQ_SILICON_VER_SHIFT	12
@@ -218,3 +219,7 @@ int zynqmp_mmio_read(const u32 address, u32 *value)
 
 	return ret;
 }
+
+U_BOOT_DRVINFO(soc_xilinx_zynqmp) = {
+	.name = "soc_xilinx_zynqmp",
+};

arch/arm/mach-zynqmp/include/mach/hardware.h

@@ -69,6 +69,9 @@ struct iou_scntr_secure {
 
 #define iou_scntr_secure ((struct iou_scntr_secure *)ZYNQMP_IOU_SCNTR_SECURE)
 
+#define ZYNQMP_PS_VERSION	0xFFCA0044
+#define ZYNQMP_PS_VER_MASK	GENMASK(1, 0)
+
 /* Bootmode setting values */
 #define BOOT_MODES_MASK	0x0000000F
 #define QSPI_MODE_24BIT	0x00000001

configs/xilinx_zynqmp_virt_defconfig

@@ -160,6 +160,7 @@ CONFIG_DM_SCSI=y
 CONFIG_ARM_DCC=y
 CONFIG_XILINX_UARTLITE=y
 CONFIG_ZYNQ_SERIAL=y
+CONFIG_SOC_XILINX_ZYNQMP=y
 CONFIG_SPI=y
 CONFIG_ZYNQ_SPI=y
 CONFIG_ZYNQMP_GQSPI=y

drivers/soc/Kconfig

@@ -16,6 +16,14 @@ config SOC_DEVICE_TI_K3
 	  This allows Texas Instruments Keystone 3 SoCs to identify
 	  specifics about the SoC in use.
 
+config SOC_XILINX_ZYNQMP
+	bool "Enable SoC Device ID driver for Xilinx ZynqMP"
+	depends on SOC_DEVICE && ARCH_ZYNQMP
+	help
+	  Enable this option to select SoC device id driver for Xilinx ZynqMP.
+	  This allows other drivers to verify the SoC familiy & revision
+	  using matching SoC attributes.
+
 source "drivers/soc/ti/Kconfig"
 
 endmenu

drivers/soc/Makefile

@@ -6,3 +6,4 @@ obj-$(CONFIG_SOC_TI) += ti/
 obj-$(CONFIG_SOC_DEVICE) += soc-uclass.o
 obj-$(CONFIG_SOC_DEVICE_TI_K3) += soc_ti_k3.o
 obj-$(CONFIG_SANDBOX) += soc_sandbox.o
+obj-$(CONFIG_SOC_XILINX_ZYNQMP) += soc_xilinx_zynqmp.o

drivers/soc/soc_xilinx_zynqmp.c

@@ -0,0 +1,78 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Xilinx ZynqMP SOC driver
+ *
+ * Copyright (C) 2021 Xilinx, Inc.
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <asm/cache.h>
+#include <soc.h>
+#include <zynqmp_firmware.h>
+#include <asm/arch/sys_proto.h>
+#include <asm/arch/hardware.h>
+
+/*
+ * Zynqmp has 4 silicon revisions
+ * v0 -> 0(XCZU9EG-ES1)
+ * v1 -> 1(XCZU3EG-ES1, XCZU15EG-ES1)
+ * v2 -> 2(XCZU7EV-ES1, XCZU9EG-ES2, XCZU19EG-ES1)
+ * v3 -> 3(Production Level)
+ */
+static const char zynqmp_family[] = "ZynqMP";
+
+struct soc_xilinx_zynqmp_priv {
+	const char *family;
+	char revision;
+};
+
+static int soc_xilinx_zynqmp_get_family(struct udevice *dev, char *buf, int size)
+{
+	struct soc_xilinx_zynqmp_priv *priv = dev_get_priv(dev);
+
+	return snprintf(buf, size, "%s", priv->family);
+}
+
+static int soc_xilinx_zynqmp_get_revision(struct udevice *dev, char *buf, int size)
+{
+	struct soc_xilinx_zynqmp_priv *priv = dev_get_priv(dev);
+
+	return snprintf(buf, size, "v%d", priv->revision);
+}
+
+static const struct soc_ops soc_xilinx_zynqmp_ops = {
+	.get_family = soc_xilinx_zynqmp_get_family,
+	.get_revision = soc_xilinx_zynqmp_get_revision,
+};
+
+static int soc_xilinx_zynqmp_probe(struct udevice *dev)
+{
+	struct soc_xilinx_zynqmp_priv *priv = dev_get_priv(dev);
+	u32 ret_payload[4];
+	int ret;
+
+	priv->family = zynqmp_family;
+
+	if (IS_ENABLED(CONFIG_SPL_BUILD) || current_el() == 3 ||
+	    !IS_ENABLED(CONFIG_ZYNQMP_FIRMWARE))
+		ret = zynqmp_mmio_read(ZYNQMP_PS_VERSION, &ret_payload[2]);
+	else
+		ret = xilinx_pm_request(PM_GET_CHIPID, 0, 0, 0, 0,
+					ret_payload);
+	if (ret < 0)
+		return ret;
+
+	priv->revision = ret_payload[2] & ZYNQMP_PS_VER_MASK;
+
+	return 0;
+}
+
+U_BOOT_DRIVER(soc_xilinx_zynqmp) = {
+	.name		= "soc_xilinx_zynqmp",
+	.id		= UCLASS_SOC,
+	.ops		= &soc_xilinx_zynqmp_ops,
+	.probe		= soc_xilinx_zynqmp_probe,
+	.priv_auto	= sizeof(struct soc_xilinx_zynqmp_priv),
+	.flags		= DM_FLAG_PRE_RELOC,
+};