178 lines · c
1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Copyright (c) 2017, National Instruments Corp.4 * Copyright (c) 2017, Xilinx Inc5 *6 * FPGA Bridge Driver for the Xilinx LogiCORE Partial Reconfiguration7 * Decoupler IP Core.8 */9 10#include <linux/clk.h>11#include <linux/io.h>12#include <linux/kernel.h>13#include <linux/module.h>14#include <linux/of.h>15#include <linux/platform_device.h>16#include <linux/property.h>17#include <linux/fpga/fpga-bridge.h>18 19#define CTRL_CMD_DECOUPLE BIT(0)20#define CTRL_CMD_COUPLE 021#define CTRL_OFFSET 022 23struct xlnx_config_data {24 const char *name;25};26 27struct xlnx_pr_decoupler_data {28 const struct xlnx_config_data *ipconfig;29 void __iomem *io_base;30 struct clk *clk;31};32 33static inline void xlnx_pr_decoupler_write(struct xlnx_pr_decoupler_data *d,34 u32 offset, u32 val)35{36 writel(val, d->io_base + offset);37}38 39static inline u32 xlnx_pr_decouple_read(const struct xlnx_pr_decoupler_data *d,40 u32 offset)41{42 return readl(d->io_base + offset);43}44 45static int xlnx_pr_decoupler_enable_set(struct fpga_bridge *bridge, bool enable)46{47 int err;48 struct xlnx_pr_decoupler_data *priv = bridge->priv;49 50 err = clk_enable(priv->clk);51 if (err)52 return err;53 54 if (enable)55 xlnx_pr_decoupler_write(priv, CTRL_OFFSET, CTRL_CMD_COUPLE);56 else57 xlnx_pr_decoupler_write(priv, CTRL_OFFSET, CTRL_CMD_DECOUPLE);58 59 clk_disable(priv->clk);60 61 return 0;62}63 64static int xlnx_pr_decoupler_enable_show(struct fpga_bridge *bridge)65{66 const struct xlnx_pr_decoupler_data *priv = bridge->priv;67 u32 status;68 int err;69 70 err = clk_enable(priv->clk);71 if (err)72 return err;73 74 status = xlnx_pr_decouple_read(priv, CTRL_OFFSET);75 76 clk_disable(priv->clk);77 78 return !status;79}80 81static const struct fpga_bridge_ops xlnx_pr_decoupler_br_ops = {82 .enable_set = xlnx_pr_decoupler_enable_set,83 .enable_show = xlnx_pr_decoupler_enable_show,84};85 86static const struct xlnx_config_data decoupler_config = {87 .name = "Xilinx PR Decoupler",88};89 90static const struct xlnx_config_data shutdown_config = {91 .name = "Xilinx DFX AXI Shutdown Manager",92};93 94static const struct of_device_id xlnx_pr_decoupler_of_match[] = {95 { .compatible = "xlnx,pr-decoupler-1.00", .data = &decoupler_config },96 { .compatible = "xlnx,pr-decoupler", .data = &decoupler_config },97 { .compatible = "xlnx,dfx-axi-shutdown-manager-1.00",98 .data = &shutdown_config },99 { .compatible = "xlnx,dfx-axi-shutdown-manager",100 .data = &shutdown_config },101 {},102};103MODULE_DEVICE_TABLE(of, xlnx_pr_decoupler_of_match);104 105static int xlnx_pr_decoupler_probe(struct platform_device *pdev)106{107 struct xlnx_pr_decoupler_data *priv;108 struct fpga_bridge *br;109 int err;110 111 priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);112 if (!priv)113 return -ENOMEM;114 115 priv->ipconfig = device_get_match_data(&pdev->dev);116 117 priv->io_base = devm_platform_ioremap_resource(pdev, 0);118 if (IS_ERR(priv->io_base))119 return PTR_ERR(priv->io_base);120 121 priv->clk = devm_clk_get(&pdev->dev, "aclk");122 if (IS_ERR(priv->clk))123 return dev_err_probe(&pdev->dev, PTR_ERR(priv->clk),124 "input clock not found\n");125 126 err = clk_prepare_enable(priv->clk);127 if (err) {128 dev_err(&pdev->dev, "unable to enable clock\n");129 return err;130 }131 132 clk_disable(priv->clk);133 134 br = fpga_bridge_register(&pdev->dev, priv->ipconfig->name,135 &xlnx_pr_decoupler_br_ops, priv);136 if (IS_ERR(br)) {137 err = PTR_ERR(br);138 dev_err(&pdev->dev, "unable to register %s",139 priv->ipconfig->name);140 goto err_clk;141 }142 143 platform_set_drvdata(pdev, br);144 145 return 0;146 147err_clk:148 clk_unprepare(priv->clk);149 150 return err;151}152 153static void xlnx_pr_decoupler_remove(struct platform_device *pdev)154{155 struct fpga_bridge *bridge = platform_get_drvdata(pdev);156 struct xlnx_pr_decoupler_data *p = bridge->priv;157 158 fpga_bridge_unregister(bridge);159 160 clk_unprepare(p->clk);161}162 163static struct platform_driver xlnx_pr_decoupler_driver = {164 .probe = xlnx_pr_decoupler_probe,165 .remove_new = xlnx_pr_decoupler_remove,166 .driver = {167 .name = "xlnx_pr_decoupler",168 .of_match_table = xlnx_pr_decoupler_of_match,169 },170};171 172module_platform_driver(xlnx_pr_decoupler_driver);173 174MODULE_DESCRIPTION("Xilinx Partial Reconfiguration Decoupler");175MODULE_AUTHOR("Moritz Fischer <mdf@kernel.org>");176MODULE_AUTHOR("Michal Simek <michal.simek@xilinx.com>");177MODULE_LICENSE("GPL v2");178