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authorArnd Bergmann <arnd@arndb.de>2019-02-15 17:21:04 +0100
committerArnd Bergmann <arnd@arndb.de>2019-02-15 17:21:32 +0100
commit6f2185f8e345c9023bdd030d7dae4affd6bea539 (patch)
treef504a5e0b2f964818a02096e4647f686ef1b9d92 /drivers/reset/reset-brcmstb.c
parentMerge tag 'amlogic-drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/... (diff)
parentdt-bindings: reset: meson: add g12a bindings (diff)
downloadlinux-6f2185f8e345c9023bdd030d7dae4affd6bea539.tar.xz
linux-6f2185f8e345c9023bdd030d7dae4affd6bea539.zip
Merge tag 'reset-for-5.1' of git://git.pengutronix.de/git/pza/linux into arm/drivers
Reset controller changes for v5.1 This adds the include/linux/reset directory to MAINTAINERS for reset specific headers and adds headers for sunxi and socfpga in there to get rid of a few extern function declarations. There is a new reset driver for the Broadcom STB reset controller and the i.MX7 system reset controller driver is extended to support i.MX8MQ as well. Finally, there is a new header with reset id constants for the Meson G12A SoC, which has a reset controller identical to Meson AXG and thus can reuse its driver and DT bindings. * tag 'reset-for-5.1' of git://git.pengutronix.de/git/pza/linux: dt-bindings: reset: meson: add g12a bindings reset: imx7: Add support for i.MX8MQ IP block variant reset: imx7: Add plubming to support multiple IP variants reset: Add Broadcom STB SW_INIT reset controller driver dt-bindings: reset: Add document for Broadcom STB reset controller reset: socfpga: declare socfpga_reset_init in a header file reset: sunxi: declare sun6i_reset_init in a header file MAINTAINERS: use include/linux/reset for reset controller related headers dt-bindings: reset: imx7: Document usage on i.MX8MQ SoCs Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Diffstat (limited to 'drivers/reset/reset-brcmstb.c')
-rw-r--r--drivers/reset/reset-brcmstb.c132
1 files changed, 132 insertions, 0 deletions
diff --git a/drivers/reset/reset-brcmstb.c b/drivers/reset/reset-brcmstb.c
new file mode 100644
index 000000000000..a608f445dad6
--- /dev/null
+++ b/drivers/reset/reset-brcmstb.c
@@ -0,0 +1,132 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Broadcom STB generic reset controller for SW_INIT style reset controller
+ *
+ * Author: Florian Fainelli <f.fainelli@gmail.com>
+ * Copyright (C) 2018 Broadcom
+ */
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/reset-controller.h>
+#include <linux/types.h>
+
+struct brcmstb_reset {
+ void __iomem *base;
+ struct reset_controller_dev rcdev;
+};
+
+#define SW_INIT_SET 0x00
+#define SW_INIT_CLEAR 0x04
+#define SW_INIT_STATUS 0x08
+
+#define SW_INIT_BIT(id) BIT((id) & 0x1f)
+#define SW_INIT_BANK(id) ((id) >> 5)
+
+/* A full bank contains extra registers that we are not utilizing but still
+ * qualify as a single bank.
+ */
+#define SW_INIT_BANK_SIZE 0x18
+
+static inline
+struct brcmstb_reset *to_brcmstb(struct reset_controller_dev *rcdev)
+{
+ return container_of(rcdev, struct brcmstb_reset, rcdev);
+}
+
+static int brcmstb_reset_assert(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ unsigned int off = SW_INIT_BANK(id) * SW_INIT_BANK_SIZE;
+ struct brcmstb_reset *priv = to_brcmstb(rcdev);
+
+ writel_relaxed(SW_INIT_BIT(id), priv->base + off + SW_INIT_SET);
+
+ return 0;
+}
+
+static int brcmstb_reset_deassert(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ unsigned int off = SW_INIT_BANK(id) * SW_INIT_BANK_SIZE;
+ struct brcmstb_reset *priv = to_brcmstb(rcdev);
+
+ writel_relaxed(SW_INIT_BIT(id), priv->base + off + SW_INIT_CLEAR);
+ /* Maximum reset delay after de-asserting a line and seeing block
+ * operation is typically 14us for the worst case, build some slack
+ * here.
+ */
+ usleep_range(100, 200);
+
+ return 0;
+}
+
+static int brcmstb_reset_status(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ unsigned int off = SW_INIT_BANK(id) * SW_INIT_BANK_SIZE;
+ struct brcmstb_reset *priv = to_brcmstb(rcdev);
+
+ return readl_relaxed(priv->base + off + SW_INIT_STATUS) &
+ SW_INIT_BIT(id);
+}
+
+static const struct reset_control_ops brcmstb_reset_ops = {
+ .assert = brcmstb_reset_assert,
+ .deassert = brcmstb_reset_deassert,
+ .status = brcmstb_reset_status,
+};
+
+static int brcmstb_reset_probe(struct platform_device *pdev)
+{
+ struct device *kdev = &pdev->dev;
+ struct brcmstb_reset *priv;
+ struct resource *res;
+
+ priv = devm_kzalloc(kdev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!IS_ALIGNED(res->start, SW_INIT_BANK_SIZE) ||
+ !IS_ALIGNED(resource_size(res), SW_INIT_BANK_SIZE)) {
+ dev_err(kdev, "incorrect register range\n");
+ return -EINVAL;
+ }
+
+ priv->base = devm_ioremap_resource(kdev, res);
+ if (IS_ERR(priv->base))
+ return PTR_ERR(priv->base);
+
+ dev_set_drvdata(kdev, priv);
+
+ priv->rcdev.owner = THIS_MODULE;
+ priv->rcdev.nr_resets = DIV_ROUND_DOWN_ULL(resource_size(res),
+ SW_INIT_BANK_SIZE) * 32;
+ priv->rcdev.ops = &brcmstb_reset_ops;
+ priv->rcdev.of_node = kdev->of_node;
+ /* Use defaults: 1 cell and simple xlate function */
+
+ return devm_reset_controller_register(kdev, &priv->rcdev);
+}
+
+static const struct of_device_id brcmstb_reset_of_match[] = {
+ { .compatible = "brcm,brcmstb-reset" },
+ { /* sentinel */ }
+};
+
+static struct platform_driver brcmstb_reset_driver = {
+ .probe = brcmstb_reset_probe,
+ .driver = {
+ .name = "brcmstb-reset",
+ .of_match_table = brcmstb_reset_of_match,
+ },
+};
+module_platform_driver(brcmstb_reset_driver);
+
+MODULE_AUTHOR("Broadcom");
+MODULE_DESCRIPTION("Broadcom STB reset controller");
+MODULE_LICENSE("GPL");