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path: root/drivers/fpga/ts73xx-fpga.c
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Diffstat (limited to 'drivers/fpga/ts73xx-fpga.c')
-rw-r--r--drivers/fpga/ts73xx-fpga.c134
1 files changed, 134 insertions, 0 deletions
diff --git a/drivers/fpga/ts73xx-fpga.c b/drivers/fpga/ts73xx-fpga.c
new file mode 100644
index 000000000..8e6e9c840
--- /dev/null
+++ b/drivers/fpga/ts73xx-fpga.c
@@ -0,0 +1,134 @@
+// 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;
+ struct resource *res;
+
+ priv = devm_kzalloc(kdev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ priv->dev = kdev;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ priv->io_base = devm_ioremap_resource(kdev, res);
+ 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");