This patch adds zynq afi config driver. This is useful for
the configuration of the PS-PL interface on zynq platform.
Signed-off-by: Nava kishore Manne <nava.manne@xxxxxxxxxx>
---
drivers/misc/Kconfig | 11 ++++++
drivers/misc/Makefile | 1 +
drivers/misc/zynq-afi.c | 81 +++++++++++++++++++++++++++++++++++++++++
3 files changed, 93 insertions(+)
create mode 100644 drivers/misc/zynq-afi.c
diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index f532c59bb59b..877b43b3377d 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -445,6 +445,17 @@ config HISI_HIKEY_USB
switching between the dual-role USB-C port and the USB-A host ports
using only one USB controller.
+config ZYNQ_AFI
+ tristate "Xilinx ZYNQ AFI support"
+ help
+ Zynq AFI driver support for writing to the AFI registers
+ for configuring PS_PL Bus-width. Xilinx Zynq SoC connect
+ the PS to the programmable logic (PL) through the AXI port.
+ This AXI port helps to establish the data path between the
+ PS and PL.In-order to establish the proper communication path
+ between PS and PL, the AXI port data path should be configured
+ with the proper Bus-width values
+
source "drivers/misc/c2port/Kconfig"
source "drivers/misc/eeprom/Kconfig"
source "drivers/misc/cb710/Kconfig"
diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
index 99b6f15a3c70..e9b03843100f 100644
--- a/drivers/misc/Makefile
+++ b/drivers/misc/Makefile
@@ -56,3 +56,4 @@ obj-$(CONFIG_HABANA_AI) += habanalabs/
obj-$(CONFIG_UACCE) += uacce/
obj-$(CONFIG_XILINX_SDFEC) += xilinx_sdfec.o
obj-$(CONFIG_HISI_HIKEY_USB) += hisi_hikey_usb.o
+obj-$(CONFIG_ZYNQ_AFI) += zynq-afi.o
diff --git a/drivers/misc/zynq-afi.c b/drivers/misc/zynq-afi.c
new file mode 100644
index 000000000000..04317d1bdb98
--- /dev/null
+++ b/drivers/misc/zynq-afi.c
@@ -0,0 +1,81 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Xilinx ZYNQ AFI driver.
+ * Copyright (c) 2018-2021 Xilinx Inc.
+ */
+
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+
+/* Registers and special values for doing register-based operations */
+#define AFI_RDCHAN_CTRL_OFFSET 0x00
+#define AFI_WRCHAN_CTRL_OFFSET 0x14
+
+#define AFI_BUSWIDTH_MASK 0x01
+
+/**
+ * struct afi_fpga - AFI register description
+ * @membase: pointer to register struct
+ * @afi_width: AFI bus width to be written
+ */
+struct zynq_afi_fpga {
+ void __iomem *membase;
+ u32 afi_width;
+};
+
+static int zynq_afi_fpga_probe(struct platform_device *pdev)
+{
+ struct zynq_afi_fpga *afi_fpga;
+ struct resource *res;
+ u32 reg_val;
+ u32 val;
+
+ afi_fpga = devm_kzalloc(&pdev->dev, sizeof(*afi_fpga), GFP_KERNEL);
+ if (!afi_fpga)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ afi_fpga->membase = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(afi_fpga->membase))
+ return PTR_ERR(afi_fpga->membase);
+
+ val = device_property_read_u32(&pdev->dev, "xlnx,afi-width",
+ &afi_fpga->afi_width);
+ if (val) {
+ dev_err(&pdev->dev, "failed to get the afi bus width\n");
+ return -EINVAL;
+ }
+
+ reg_val = readl(afi_fpga->membase + AFI_RDCHAN_CTRL_OFFSET);
+ reg_val &= ~AFI_BUSWIDTH_MASK;
+ writel(reg_val | afi_fpga->afi_width,
+ afi_fpga->membase + AFI_RDCHAN_CTRL_OFFSET);
+ reg_val = readl(afi_fpga->membase + AFI_WRCHAN_CTRL_OFFSET);
+ reg_val &= ~AFI_BUSWIDTH_MASK;
+ writel(reg_val | afi_fpga->afi_width,
+ afi_fpga->membase + AFI_WRCHAN_CTRL_OFFSET);
+
+ return 0;
+}
+
+static const struct of_device_id zynq_afi_fpga_ids[] = {
+ { .compatible = "xlnx,zynq-afi-fpga" },
+ { },
+};
+MODULE_DEVICE_TABLE(of, zynq_afi_fpga_ids);
+
+static struct platform_driver zynq_afi_fpga_driver = {
+ .driver = {
+ .name = "zynq-afi-fpga",
+ .of_match_table = zynq_afi_fpga_ids,
+ },
+ .probe = zynq_afi_fpga_probe,
+};
+module_platform_driver(zynq_afi_fpga_driver);
+
+MODULE_DESCRIPTION("ZYNQ FPGA AFI module");
+MODULE_AUTHOR("Nava kishore Manne <nava.manne@xxxxxxxxxx>");
+MODULE_LICENSE("GPL v2");
--
2.18.0
