@@ -109,6 +109,7 @@ config ARCH_OMAP2PLUS
select TI_SYSC
select OMAP_IRQCHIP
select CLKSRC_TI_32K
+ select ARCH_HAS_RESET_CONTROLLER
help
Systems based on OMAP2, OMAP3, OMAP4 or OMAP5
@@ -6,6 +6,7 @@ obj-$(CONFIG_KEYSTONE_NAVIGATOR_QMSS) += knav_qmss.o
knav_qmss-y := knav_qmss_queue.o knav_qmss_acc.o
obj-$(CONFIG_KEYSTONE_NAVIGATOR_DMA) += knav_dma.o
obj-$(CONFIG_AMX3_PM) += pm33xx.o
+obj-$(CONFIG_ARCH_OMAP2PLUS) += omap_prm.o
obj-$(CONFIG_WKUP_M3_IPC) += wkup_m3_ipc.o
obj-$(CONFIG_TI_SCI_PM_DOMAINS) += ti_sci_pm_domains.o
obj-$(CONFIG_TI_SCI_INTA_MSI_DOMAIN) += ti_sci_inta_msi.o
new file mode 100644
@@ -0,0 +1,258 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * OMAP2+ PRM driver
+ *
+ * Copyright (C) 2019 Texas Instruments Incorporated - http://www.ti.com/
+ * Tero Kristo <t-kristo@ti.com>
+ */
+
+#include <linux/kernel.h>
+#include <linux/device.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/reset-controller.h>
+#include <linux/delay.h>
+
+struct omap_rst_map {
+ s8 rst;
+ s8 st;
+};
+
+struct omap_prm_data {
+ u32 base;
+ const char *name;
+ u16 rstctrl;
+ u16 rstst;
+ const struct omap_rst_map *rstmap;
+ u8 flags;
+};
+
+struct omap_prm {
+ const struct omap_prm_data *data;
+ void __iomem *base;
+};
+
+struct omap_reset_data {
+ struct reset_controller_dev rcdev;
+ struct omap_prm *prm;
+ u32 mask;
+ spinlock_t lock;
+};
+
+#define to_omap_reset_data(p) container_of((p), struct omap_reset_data, rcdev)
+
+#define OMAP_MAX_RESETS 8
+#define OMAP_RESET_MAX_WAIT 10000
+
+#define OMAP_PRM_HAS_RSTCTRL BIT(0)
+#define OMAP_PRM_HAS_RSTST BIT(1)
+
+#define OMAP_PRM_HAS_RESETS (OMAP_PRM_HAS_RSTCTRL | OMAP_PRM_HAS_RSTST)
+
+static const struct of_device_id omap_prm_id_table[] = {
+ { },
+};
+
+static bool _is_valid_reset(struct omap_reset_data *reset, unsigned long id)
+{
+ if (reset->mask & BIT(id))
+ return true;
+
+ return false;
+}
+
+static int omap_reset_get_st_bit(struct omap_reset_data *reset,
+ unsigned long id)
+{
+ const struct omap_rst_map *map = reset->prm->data->rstmap;
+
+ while (map->rst >= 0) {
+ if (map->rst == id)
+ return map->st;
+
+ map++;
+ }
+
+ return id;
+}
+
+static int omap_reset_status(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ struct omap_reset_data *reset = to_omap_reset_data(rcdev);
+ u32 v;
+ int st_bit = omap_reset_get_st_bit(reset, id);
+ bool has_rstst = reset->prm->data->rstst ||
+ (reset->prm->data->flags & OMAP_PRM_HAS_RSTST);
+
+ /* Check if we have rstst */
+ if (!has_rstst)
+ return -ENOTSUPP;
+
+ /* Check if hw reset line is asserted */
+ v = readl_relaxed(reset->prm->base + reset->prm->data->rstctrl);
+ if (v & BIT(id))
+ return 1;
+
+ /*
+ * Check reset status, high value means reset sequence has been
+ * completed successfully so we can return 0 here (reset deasserted)
+ */
+ v = readl_relaxed(reset->prm->base + reset->prm->data->rstst);
+ v >>= st_bit;
+ v &= 1;
+
+ return !v;
+}
+
+static int omap_reset_assert(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ struct omap_reset_data *reset = to_omap_reset_data(rcdev);
+ u32 v;
+ unsigned long flags;
+
+ /* assert the reset control line */
+ spin_lock_irqsave(&reset->lock, flags);
+ v = readl_relaxed(reset->prm->base + reset->prm->data->rstctrl);
+ v |= 1 << id;
+ writel_relaxed(v, reset->prm->base + reset->prm->data->rstctrl);
+ spin_unlock_irqrestore(&reset->lock, flags);
+
+ return 0;
+}
+
+static int omap_reset_deassert(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ struct omap_reset_data *reset = to_omap_reset_data(rcdev);
+ u32 v;
+ int st_bit;
+ bool has_rstst;
+ unsigned long flags;
+
+ has_rstst = reset->prm->data->rstst ||
+ (reset->prm->data->flags & OMAP_PRM_HAS_RSTST);
+
+ if (has_rstst) {
+ st_bit = omap_reset_get_st_bit(reset, id);
+
+ /* Clear the reset status by writing 1 to the status bit */
+ v = 1 << st_bit;
+ writel_relaxed(v, reset->prm->base + reset->prm->data->rstst);
+ }
+
+ /* de-assert the reset control line */
+ spin_lock_irqsave(&reset->lock, flags);
+ v = readl_relaxed(reset->prm->base + reset->prm->data->rstctrl);
+ v &= ~(1 << id);
+ writel_relaxed(v, reset->prm->base + reset->prm->data->rstctrl);
+ spin_unlock_irqrestore(&reset->lock, flags);
+
+ return 0;
+}
+
+static const struct reset_control_ops omap_reset_ops = {
+ .assert = omap_reset_assert,
+ .deassert = omap_reset_deassert,
+ .status = omap_reset_status,
+};
+
+static int omap_prm_reset_xlate(struct reset_controller_dev *rcdev,
+ const struct of_phandle_args *reset_spec)
+{
+ struct omap_reset_data *reset = to_omap_reset_data(rcdev);
+
+ if (!_is_valid_reset(reset, reset_spec->args[0]))
+ return -EINVAL;
+
+ return reset_spec->args[0];
+}
+
+static int omap_prm_reset_init(struct platform_device *pdev,
+ struct omap_prm *prm)
+{
+ struct omap_reset_data *reset;
+ const struct omap_rst_map *map;
+
+ /*
+ * Check if we have controllable resets. If either rstctrl is non-zero
+ * or OMAP_PRM_HAS_RSTCTRL flag is set, we have reset control register
+ * for the domain.
+ */
+ if (!prm->data->rstctrl && !(prm->data->flags & OMAP_PRM_HAS_RSTCTRL))
+ return 0;
+
+ map = prm->data->rstmap;
+ if (!map)
+ return -EINVAL;
+
+ reset = devm_kzalloc(&pdev->dev, sizeof(*reset), GFP_KERNEL);
+ if (!reset)
+ return -ENOMEM;
+
+ reset->rcdev.owner = THIS_MODULE;
+ reset->rcdev.ops = &omap_reset_ops;
+ reset->rcdev.of_node = pdev->dev.of_node;
+ reset->rcdev.nr_resets = OMAP_MAX_RESETS;
+ reset->rcdev.of_xlate = omap_prm_reset_xlate;
+ reset->rcdev.of_reset_n_cells = 1;
+ spin_lock_init(&reset->lock);
+
+ reset->prm = prm;
+
+ while (map->rst >= 0) {
+ reset->mask |= BIT(map->rst);
+ map++;
+ }
+
+ return devm_reset_controller_register(&pdev->dev, &reset->rcdev);
+}
+
+static int omap_prm_probe(struct platform_device *pdev)
+{
+ struct resource *res;
+ const struct omap_prm_data *data;
+ struct omap_prm *prm;
+ const struct of_device_id *match;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res)
+ return -ENODEV;
+
+ match = of_match_device(omap_prm_id_table, &pdev->dev);
+ if (!match)
+ return -ENOTSUPP;
+
+ prm = devm_kzalloc(&pdev->dev, sizeof(*prm), GFP_KERNEL);
+ if (!prm)
+ return -ENOMEM;
+
+ data = match->data;
+
+ while (data->base != res->start) {
+ if (!data->base)
+ return -EINVAL;
+ data++;
+ }
+
+ prm->data = data;
+
+ prm->base = devm_ioremap_resource(&pdev->dev, res);
+ if (!prm->base)
+ return -ENOMEM;
+
+ return omap_prm_reset_init(pdev, prm);
+}
+
+static struct platform_driver omap_prm_driver = {
+ .probe = omap_prm_probe,
+ .driver = {
+ .name = KBUILD_MODNAME,
+ .of_match_table = omap_prm_id_table,
+ },
+};
+builtin_platform_driver(omap_prm_driver);