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authorVineet Gupta <Vineet.Gupta1@synopsys.com>2017-08-31 20:06:07 +0200
committerPhilipp Zabel <p.zabel@pengutronix.de>2017-09-18 13:02:03 +0200
commit13541226dc056fa3f54417ce12f18ba711a1591c (patch)
tree164b3545a4777727e5c41fa26a21a5d81acfbfbf /drivers/reset/reset-hsdk.c
parentARC: reset: add missing DT binding documentation for HSDKv1 reset driver (diff)
downloadlinux-13541226dc056fa3f54417ce12f18ba711a1591c.tar.xz
linux-13541226dc056fa3f54417ce12f18ba711a1591c.zip
ARC: reset: remove the misleading v1 suffix all over
There is no plan yet to do a v2 board. And even if we were to do it only some IPs would actually change, so it be best to add suffixes at that point, not now ! Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Diffstat (limited to 'drivers/reset/reset-hsdk.c')
-rw-r--r--drivers/reset/reset-hsdk.c137
1 files changed, 137 insertions, 0 deletions
diff --git a/drivers/reset/reset-hsdk.c b/drivers/reset/reset-hsdk.c
new file mode 100644
index 000000000000..8bce391c6943
--- /dev/null
+++ b/drivers/reset/reset-hsdk.c
@@ -0,0 +1,137 @@
+/*
+ * Copyright (C) 2017 Synopsys.
+ *
+ * Synopsys HSDK Development platform reset driver.
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/reset-controller.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+
+#define to_hsdk_rst(p) container_of((p), struct hsdk_rst, rcdev)
+
+struct hsdk_rst {
+ void __iomem *regs_ctl;
+ void __iomem *regs_rst;
+ spinlock_t lock;
+ struct reset_controller_dev rcdev;
+};
+
+static const u32 rst_map[] = {
+ BIT(16), /* APB_RST */
+ BIT(17), /* AXI_RST */
+ BIT(18), /* ETH_RST */
+ BIT(19), /* USB_RST */
+ BIT(20), /* SDIO_RST */
+ BIT(21), /* HDMI_RST */
+ BIT(22), /* GFX_RST */
+ BIT(25), /* DMAC_RST */
+ BIT(31), /* EBI_RST */
+};
+
+#define HSDK_MAX_RESETS ARRAY_SIZE(rst_map)
+
+#define CGU_SYS_RST_CTRL 0x0
+#define CGU_IP_SW_RESET 0x0
+#define CGU_IP_SW_RESET_DELAY_SHIFT 16
+#define CGU_IP_SW_RESET_DELAY_MASK GENMASK(31, CGU_IP_SW_RESET_DELAY_SHIFT)
+#define CGU_IP_SW_RESET_DELAY 0
+#define CGU_IP_SW_RESET_RESET BIT(0)
+#define SW_RESET_TIMEOUT 10000
+
+static void hsdk_reset_config(struct hsdk_rst *rst, unsigned long id)
+{
+ writel(rst_map[id], rst->regs_ctl + CGU_SYS_RST_CTRL);
+}
+
+static int hsdk_reset_do(struct hsdk_rst *rst)
+{
+ u32 reg;
+
+ reg = readl(rst->regs_rst + CGU_IP_SW_RESET);
+ reg &= ~CGU_IP_SW_RESET_DELAY_MASK;
+ reg |= CGU_IP_SW_RESET_DELAY << CGU_IP_SW_RESET_DELAY_SHIFT;
+ reg |= CGU_IP_SW_RESET_RESET;
+ writel(reg, rst->regs_rst + CGU_IP_SW_RESET);
+
+ /* wait till reset bit is back to 0 */
+ return readl_poll_timeout_atomic(rst->regs_rst + CGU_IP_SW_RESET, reg,
+ !(reg & CGU_IP_SW_RESET_RESET), 5, SW_RESET_TIMEOUT);
+}
+
+static int hsdk_reset_reset(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ struct hsdk_rst *rst = to_hsdk_rst(rcdev);
+ unsigned long flags;
+ int ret;
+
+ spin_lock_irqsave(&rst->lock, flags);
+ hsdk_reset_config(rst, id);
+ ret = hsdk_reset_do(rst);
+ spin_unlock_irqrestore(&rst->lock, flags);
+
+ return ret;
+}
+
+static const struct reset_control_ops hsdk_reset_ops = {
+ .reset = hsdk_reset_reset,
+};
+
+static int hsdk_reset_probe(struct platform_device *pdev)
+{
+ struct hsdk_rst *rst;
+ struct resource *mem;
+
+ rst = devm_kzalloc(&pdev->dev, sizeof(*rst), GFP_KERNEL);
+ if (!rst)
+ return -ENOMEM;
+
+ mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ rst->regs_ctl = devm_ioremap_resource(&pdev->dev, mem);
+ if (IS_ERR(rst->regs_ctl))
+ return PTR_ERR(rst->regs_ctl);
+
+ mem = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+ rst->regs_rst = devm_ioremap_resource(&pdev->dev, mem);
+ if (IS_ERR(rst->regs_rst))
+ return PTR_ERR(rst->regs_rst);
+
+ spin_lock_init(&rst->lock);
+
+ rst->rcdev.owner = THIS_MODULE;
+ rst->rcdev.ops = &hsdk_reset_ops;
+ rst->rcdev.of_node = pdev->dev.of_node;
+ rst->rcdev.nr_resets = HSDK_MAX_RESETS;
+ rst->rcdev.of_reset_n_cells = 1;
+
+ return reset_controller_register(&rst->rcdev);
+}
+
+static const struct of_device_id hsdk_reset_dt_match[] = {
+ { .compatible = "snps,hsdk-reset" },
+ { },
+};
+
+static struct platform_driver hsdk_reset_driver = {
+ .probe = hsdk_reset_probe,
+ .driver = {
+ .name = "hsdk-reset",
+ .of_match_table = hsdk_reset_dt_match,
+ },
+};
+builtin_platform_driver(hsdk_reset_driver);
+
+MODULE_AUTHOR("Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>");
+MODULE_DESCRIPTION("Synopsys HSDK SDP reset driver");
+MODULE_LICENSE("GPL v2");