diff options
Diffstat (limited to 'drivers/fpga/ts73xx-fpga.c')
| -rw-r--r-- | drivers/fpga/ts73xx-fpga.c | 132 |
1 files changed, 132 insertions, 0 deletions
diff --git a/drivers/fpga/ts73xx-fpga.c b/drivers/fpga/ts73xx-fpga.c new file mode 100644 index 0000000000..4e1d2a4d3d --- /dev/null +++ b/drivers/fpga/ts73xx-fpga.c @@ -0,0 +1,132 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Technologic Systems TS-73xx SBC FPGA loader + * + * Copyright (C) 2016 Florian Fainelli <f.fainelli@gmail.com> + * + * FPGA Manager Driver for the on-board Altera Cyclone II FPGA found on + * TS-7300, heavily based on load_fpga.c in their vendor tree. + */ + +#include <linux/delay.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/string.h> +#include <linux/iopoll.h> +#include <linux/fpga/fpga-mgr.h> + +#define TS73XX_FPGA_DATA_REG 0 +#define TS73XX_FPGA_CONFIG_REG 1 + +#define TS73XX_FPGA_WRITE_DONE 0x1 +#define TS73XX_FPGA_WRITE_DONE_TIMEOUT 1000 /* us */ +#define TS73XX_FPGA_RESET 0x2 +#define TS73XX_FPGA_RESET_LOW_DELAY 30 /* us */ +#define TS73XX_FPGA_RESET_HIGH_DELAY 80 /* us */ +#define TS73XX_FPGA_LOAD_OK 0x4 +#define TS73XX_FPGA_CONFIG_LOAD 0x8 + +struct ts73xx_fpga_priv { + void __iomem *io_base; + struct device *dev; +}; + +static int ts73xx_fpga_write_init(struct fpga_manager *mgr, + struct fpga_image_info *info, + const char *buf, size_t count) +{ + struct ts73xx_fpga_priv *priv = mgr->priv; + + /* Reset the FPGA */ + writeb(0, priv->io_base + TS73XX_FPGA_CONFIG_REG); + udelay(TS73XX_FPGA_RESET_LOW_DELAY); + writeb(TS73XX_FPGA_RESET, priv->io_base + TS73XX_FPGA_CONFIG_REG); + udelay(TS73XX_FPGA_RESET_HIGH_DELAY); + + return 0; +} + +static int ts73xx_fpga_write(struct fpga_manager *mgr, const char *buf, + size_t count) +{ + struct ts73xx_fpga_priv *priv = mgr->priv; + size_t i = 0; + int ret; + u8 reg; + + while (count--) { + ret = readb_poll_timeout(priv->io_base + TS73XX_FPGA_CONFIG_REG, + reg, !(reg & TS73XX_FPGA_WRITE_DONE), + 1, TS73XX_FPGA_WRITE_DONE_TIMEOUT); + if (ret < 0) + return ret; + + writeb(buf[i], priv->io_base + TS73XX_FPGA_DATA_REG); + i++; + } + + return 0; +} + +static int ts73xx_fpga_write_complete(struct fpga_manager *mgr, + struct fpga_image_info *info) +{ + struct ts73xx_fpga_priv *priv = mgr->priv; + u8 reg; + + usleep_range(1000, 2000); + reg = readb(priv->io_base + TS73XX_FPGA_CONFIG_REG); + reg |= TS73XX_FPGA_CONFIG_LOAD; + writeb(reg, priv->io_base + TS73XX_FPGA_CONFIG_REG); + + usleep_range(1000, 2000); + reg = readb(priv->io_base + TS73XX_FPGA_CONFIG_REG); + reg &= ~TS73XX_FPGA_CONFIG_LOAD; + writeb(reg, priv->io_base + TS73XX_FPGA_CONFIG_REG); + + reg = readb(priv->io_base + TS73XX_FPGA_CONFIG_REG); + if ((reg & TS73XX_FPGA_LOAD_OK) != TS73XX_FPGA_LOAD_OK) + return -ETIMEDOUT; + + return 0; +} + +static const struct fpga_manager_ops ts73xx_fpga_ops = { + .write_init = ts73xx_fpga_write_init, + .write = ts73xx_fpga_write, + .write_complete = ts73xx_fpga_write_complete, +}; + +static int ts73xx_fpga_probe(struct platform_device *pdev) +{ + struct device *kdev = &pdev->dev; + struct ts73xx_fpga_priv *priv; + struct fpga_manager *mgr; + + priv = devm_kzalloc(kdev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->dev = kdev; + + priv->io_base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(priv->io_base)) + return PTR_ERR(priv->io_base); + + mgr = devm_fpga_mgr_register(kdev, "TS-73xx FPGA Manager", + &ts73xx_fpga_ops, priv); + return PTR_ERR_OR_ZERO(mgr); +} + +static struct platform_driver ts73xx_fpga_driver = { + .driver = { + .name = "ts73xx-fpga-mgr", + }, + .probe = ts73xx_fpga_probe, +}; +module_platform_driver(ts73xx_fpga_driver); + +MODULE_AUTHOR("Florian Fainelli <f.fainelli@gmail.com>"); +MODULE_DESCRIPTION("TS-73xx FPGA Manager driver"); +MODULE_LICENSE("GPL v2"); |