linux/drivers/fpga/xilinx-pr-decoupler.c
Nava kishore Manne 6f1e376cfc fpga: Add support for Xilinx DFX AXI Shutdown manager
This patch adds support for Xilinx Dynamic Function eXchange(DFX) AXI
shutdown manager IP. It can be used to safely handling the AXI traffic
on a Reconfigurable Partition when it is undergoing dynamic reconfiguration
and there by preventing system deadlock that may occur if AXI transactions
are interrupted during reconfiguration.

PR-Decoupler and AXI shutdown manager are completely different IPs.
But both the IP registers are compatible and also both belong to the
same sub-system (fpga-bridge).So using same driver for both IP's.

Signed-off-by: Nava kishore Manne <nava.manne@xilinx.com>
Reviewed-by: Tom Rix <trix@redhat.com>
Signed-off-by: Moritz Fischer <mdf@kernel.org>
2021-03-06 07:54:40 -08:00

192 lines
4.4 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (c) 2017, National Instruments Corp.
* Copyright (c) 2017, Xilinx Inc
*
* FPGA Bridge Driver for the Xilinx LogiCORE Partial Reconfiguration
* Decoupler IP Core.
*/
#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_config_data {
const char *name;
};
struct xlnx_pr_decoupler_data {
const struct xlnx_config_data *ipconfig;
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 const 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 xlnx_config_data decoupler_config = {
.name = "Xilinx PR Decoupler",
};
static const struct xlnx_config_data shutdown_config = {
.name = "Xilinx DFX AXI Shutdown Manager",
};
static const struct of_device_id xlnx_pr_decoupler_of_match[] = {
{ .compatible = "xlnx,pr-decoupler-1.00", .data = &decoupler_config },
{ .compatible = "xlnx,pr-decoupler", .data = &decoupler_config },
{ .compatible = "xlnx,dfx-axi-shutdown-manager-1.00",
.data = &shutdown_config },
{ .compatible = "xlnx,dfx-axi-shutdown-manager",
.data = &shutdown_config },
{},
};
MODULE_DEVICE_TABLE(of, xlnx_pr_decoupler_of_match);
static int xlnx_pr_decoupler_probe(struct platform_device *pdev)
{
struct device_node *np = pdev->dev.of_node;
struct xlnx_pr_decoupler_data *priv;
struct fpga_bridge *br;
int err;
struct resource *res;
priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
if (np) {
const struct of_device_id *match;
match = of_match_node(xlnx_pr_decoupler_of_match, np);
if (match && match->data)
priv->ipconfig = match->data;
}
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))
return dev_err_probe(&pdev->dev, PTR_ERR(priv->clk),
"input clock not found\n");
err = clk_prepare_enable(priv->clk);
if (err) {
dev_err(&pdev->dev, "unable to enable clock\n");
return err;
}
clk_disable(priv->clk);
br = devm_fpga_bridge_create(&pdev->dev, priv->ipconfig->name,
&xlnx_pr_decoupler_br_ops, priv);
if (!br) {
err = -ENOMEM;
goto err_clk;
}
platform_set_drvdata(pdev, br);
err = fpga_bridge_register(br);
if (err) {
dev_err(&pdev->dev, "unable to register %s",
priv->ipconfig->name);
goto err_clk;
}
return 0;
err_clk:
clk_unprepare(priv->clk);
return err;
}
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(bridge);
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@kernel.org>");
MODULE_AUTHOR("Michal Simek <michal.simek@xilinx.com>");
MODULE_LICENSE("GPL v2");