This adds support for the Xilinx LogiCORE PR Decoupler soft-ip that does decoupling of PR regions in the FPGA fabric during partial reconfiguration. Signed-off-by: Moritz Fischer <mdf@xxxxxxxxxx> Signed-off-by: Michal Simek <michal.simek@xxxxxxxxxx> Cc: Sören Brinkmann <soren.brinkmann@xxxxxxxxxx> Cc: linux-kernel@xxxxxxxxxxxxxxx Cc: devicetree@xxxxxxxxxxxxxxx --- Changes from v3: - Adressed build bot issues Changes from v2: - Added Michal's Signed-off-by - Added "xlnx,pr-decoupler" unversioned fallback Changes from v1: - Added Michal as Co-Author since I pulled in some of his code - Reworked clk handling in _remove() - Pulled in Michal's version of show_enable(), ditched priv->enabled --- drivers/fpga/Kconfig | 10 +++ drivers/fpga/Makefile | 1 + drivers/fpga/xilinx-pr-decoupler.c | 161 +++++++++++++++++++++++++++++++++++++ 3 files changed, 172 insertions(+) create mode 100644 drivers/fpga/xilinx-pr-decoupler.c diff --git a/drivers/fpga/Kconfig b/drivers/fpga/Kconfig index ce861a2..6eabfbe 100644 --- a/drivers/fpga/Kconfig +++ b/drivers/fpga/Kconfig @@ -63,6 +63,16 @@ config ALTERA_FREEZE_BRIDGE isolate one region of the FPGA from the busses while that region is being reprogrammed. +config XILINX_PR_DECOUPLER + tristate "Xilinx LogiCORE PR Decoupler" + depends on FPGA_BRIDGE + depends on HAS_IOMEM + help + Say Y to enable drivers for Xilinx LogiCORE PR Decoupler. + The PR Decoupler exists in the FPGA fabric to isolate one + region of the FPGA from the busses while that region is + being reprogrammed during partial reconfig. + endif # FPGA endmenu diff --git a/drivers/fpga/Makefile b/drivers/fpga/Makefile index 8df07bc..ba94b79 100644 --- a/drivers/fpga/Makefile +++ b/drivers/fpga/Makefile @@ -14,6 +14,7 @@ obj-$(CONFIG_FPGA_MGR_ZYNQ_FPGA) += zynq-fpga.o obj-$(CONFIG_FPGA_BRIDGE) += fpga-bridge.o obj-$(CONFIG_SOCFPGA_FPGA_BRIDGE) += altera-hps2fpga.o altera-fpga2sdram.o obj-$(CONFIG_ALTERA_FREEZE_BRIDGE) += altera-freeze-bridge.o +obj-$(CONFIG_XILINX_PR_DECOUPLER) += xilinx-pr-decoupler.o # High Level Interfaces obj-$(CONFIG_FPGA_REGION) += fpga-region.o diff --git a/drivers/fpga/xilinx-pr-decoupler.c b/drivers/fpga/xilinx-pr-decoupler.c new file mode 100644 index 0000000..e359930 --- /dev/null +++ b/drivers/fpga/xilinx-pr-decoupler.c @@ -0,0 +1,161 @@ +/* + * Copyright (c) 2017, National Instruments Corp. + * Copyright (c) 2017, Xilix Inc + * + * FPGA Bridge Driver for the Xilinx LogiCORE Partial Reconfiguration + * Decoupler IP Core. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; version 2 of the License. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/clk.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/of_device.h> +#include <linux/module.h> +#include <linux/fpga/fpga-bridge.h> + +#define CTRL_CMD_DECOUPLE BIT(0) +#define CTRL_CMD_COUPLE 0 +#define CTRL_OFFSET 0 + +struct xlnx_pr_decoupler_data { + void __iomem *io_base; + struct clk *clk; +}; + +static inline void xlnx_pr_decoupler_write(struct xlnx_pr_decoupler_data *d, + u32 offset, u32 val) +{ + writel(val, d->io_base + offset); +} + +static inline u32 xlnx_pr_decouple_read(const struct xlnx_pr_decoupler_data *d, + u32 offset) +{ + return readl(d->io_base + offset); +} + +static int xlnx_pr_decoupler_enable_set(struct fpga_bridge *bridge, bool enable) +{ + int err; + struct xlnx_pr_decoupler_data *priv = bridge->priv; + + err = clk_enable(priv->clk); + if (err) + return err; + + if (enable) + xlnx_pr_decoupler_write(priv, CTRL_OFFSET, CTRL_CMD_COUPLE); + else + xlnx_pr_decoupler_write(priv, CTRL_OFFSET, CTRL_CMD_DECOUPLE); + + clk_disable(priv->clk); + + return 0; +} + +static int xlnx_pr_decoupler_enable_show(struct fpga_bridge *bridge) +{ + const struct xlnx_pr_decoupler_data *priv = bridge->priv; + u32 status; + int err; + + err = clk_enable(priv->clk); + if (err) + return err; + + status = readl(priv->io_base); + + clk_disable(priv->clk); + + return !status; +} + +static struct fpga_bridge_ops xlnx_pr_decoupler_br_ops = { + .enable_set = xlnx_pr_decoupler_enable_set, + .enable_show = xlnx_pr_decoupler_enable_show, +}; + +static const struct of_device_id xlnx_pr_decoupler_of_match[] = { + { .compatible = "xlnx,pr-decoupler-1.00", }, + { .compatible = "xlnx,pr-decoupler", }, + {}, +}; +MODULE_DEVICE_TABLE(of, xlnx_pr_decoupler_of_match); + +static int xlnx_pr_decoupler_probe(struct platform_device *pdev) +{ + struct xlnx_pr_decoupler_data *priv; + int err; + struct resource *res; + + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + priv->io_base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(priv->io_base)) + return PTR_ERR(priv->io_base); + + priv->clk = devm_clk_get(&pdev->dev, "aclk"); + if (IS_ERR(priv->clk)) { + dev_err(&pdev->dev, "input clock not found\n"); + return PTR_ERR(priv->clk); + } + + err = clk_prepare_enable(priv->clk); + if (err) { + dev_err(&pdev->dev, "unable to enable clock\n"); + return err; + } + + clk_disable(priv->clk); + + err = fpga_bridge_register(&pdev->dev, "Xilinx PR Decoupler", + &xlnx_pr_decoupler_br_ops, priv); + + if (err) { + dev_err(&pdev->dev, "unable to register Xilinx PR Decoupler"); + clk_unprepare(priv->clk); + return err; + } + + return 0; +} + +static int xlnx_pr_decoupler_remove(struct platform_device *pdev) +{ + struct fpga_bridge *bridge = platform_get_drvdata(pdev); + struct xlnx_pr_decoupler_data *p = bridge->priv; + + fpga_bridge_unregister(&pdev->dev); + + clk_unprepare(p->clk); + + return 0; +} + +static struct platform_driver xlnx_pr_decoupler_driver = { + .probe = xlnx_pr_decoupler_probe, + .remove = xlnx_pr_decoupler_remove, + .driver = { + .name = "xlnx_pr_decoupler", + .of_match_table = of_match_ptr(xlnx_pr_decoupler_of_match), + }, +}; + +module_platform_driver(xlnx_pr_decoupler_driver); + +MODULE_DESCRIPTION("Xilinx Partial Reconfiguration Decoupler"); +MODULE_AUTHOR("Moritz Fischer <mdf@xxxxxxxxxx>"); +MODULE_AUTHOR("Michal Simek <michal.simek@xxxxxxxxxx>"); +MODULE_LICENSE("GPL v2"); -- 2.7.4 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html