1 // SPDX-License-Identifier: GPL-2.0
3  * FPGA to/from HPS Bridge Driver for Altera SoCFPGA Devices
5  *  Copyright (C) 2013-2016 Altera Corporation, All Rights Reserved.
8  *   fpga: altera-hps2fpga: fix HPS2FPGA bridge visibility to L3 masters
9  *   Signed-off-by: Anatolij Gustschin <[email protected]>
13  * This driver manages bridges on a Altera SOCFPGA between the ARM host
19  * reprogramming the FPGA and re-enabled after the FPGA has been programmed.
23 #include <linux/fpga/fpga-bridge.h>
39 #define LWHPS2FPGA_BRIDGE_NAME			"lwhps2fpga"
50 static int alt_hps2fpga_enable_show(struct fpga_bridge *bridge)  in alt_hps2fpga_enable_show()  argument
52 	struct altera_hps2fpga_data *priv = bridge->priv;  in alt_hps2fpga_enable_show()
54 	return reset_control_status(priv->bridge_reset);  in alt_hps2fpga_enable_show()
67 	/* bring bridge out of reset */  in _alt_hps2fpga_enable_set()
69 		ret = reset_control_deassert(priv->bridge_reset);  in _alt_hps2fpga_enable_set()
71 		ret = reset_control_assert(priv->bridge_reset);  in _alt_hps2fpga_enable_set()
75 	/* Allow bridge to be visible to L3 masters or not */  in _alt_hps2fpga_enable_set()
76 	if (priv->remap_mask) {  in _alt_hps2fpga_enable_set()
81 			l3_remap_shadow |= priv->remap_mask;  in _alt_hps2fpga_enable_set()
83 			l3_remap_shadow &= ~priv->remap_mask;  in _alt_hps2fpga_enable_set()
85 		ret = regmap_write(priv->l3reg, ALT_L3_REMAP_OFST,  in _alt_hps2fpga_enable_set()
93 static int alt_hps2fpga_enable_set(struct fpga_bridge *bridge, bool enable)  in alt_hps2fpga_enable_set()  argument
95 	return _alt_hps2fpga_enable_set(bridge->priv, enable);  in alt_hps2fpga_enable_set()
118 	{ .compatible = "altr,socfpga-hps2fpga-bridge",
120 	{ .compatible = "altr,socfpga-lwhps2fpga-bridge",
122 	{ .compatible = "altr,socfpga-fpga2hps-bridge",
129 	struct device *dev = &pdev->dev;  in alt_fpga_bridge_probe()
137 	priv->bridge_reset = of_reset_control_get_exclusive_by_index(dev->of_node,  in alt_fpga_bridge_probe()
139 	if (IS_ERR(priv->bridge_reset)) {  in alt_fpga_bridge_probe()
140 		dev_err(dev, "Could not get %s reset control\n", priv->name);  in alt_fpga_bridge_probe()
141 		return PTR_ERR(priv->bridge_reset);  in alt_fpga_bridge_probe()
144 	if (priv->remap_mask) {  in alt_fpga_bridge_probe()
145 		priv->l3reg = syscon_regmap_lookup_by_compatible("altr,l3regs");  in alt_fpga_bridge_probe()
146 		if (IS_ERR(priv->l3reg)) {  in alt_fpga_bridge_probe()
148 			return PTR_ERR(priv->l3reg);  in alt_fpga_bridge_probe()
152 	priv->clk = devm_clk_get(dev, NULL);  in alt_fpga_bridge_probe()
153 	if (IS_ERR(priv->clk)) {  in alt_fpga_bridge_probe()
155 		return PTR_ERR(priv->clk);  in alt_fpga_bridge_probe()
158 	ret = clk_prepare_enable(priv->clk);  in alt_fpga_bridge_probe()
161 		return -EBUSY;  in alt_fpga_bridge_probe()
164 	if (!of_property_read_u32(dev->of_node, "bridge-enable", &enable)) {  in alt_fpga_bridge_probe()
166 			dev_warn(dev, "invalid bridge-enable %u > 1\n", enable);  in alt_fpga_bridge_probe()
168 			dev_info(dev, "%s bridge\n",  in alt_fpga_bridge_probe()
177 	br = fpga_bridge_register(dev, priv->name,  in alt_fpga_bridge_probe()
189 	clk_disable_unprepare(priv->clk);  in alt_fpga_bridge_probe()
196 	struct fpga_bridge *bridge = platform_get_drvdata(pdev);  in alt_fpga_bridge_remove()  local
197 	struct altera_hps2fpga_data *priv = bridge->priv;  in alt_fpga_bridge_remove()
199 	fpga_bridge_unregister(bridge);  in alt_fpga_bridge_remove()
201 	clk_disable_unprepare(priv->clk);  in alt_fpga_bridge_remove()
217 MODULE_DESCRIPTION("Altera SoCFPGA HPS to FPGA Bridge");