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-rw-r--r--MAINTAINERS6
-rw-r--r--drivers/hwspinlock/Kconfig9
-rw-r--r--drivers/hwspinlock/Makefile1
-rw-r--r--drivers/hwspinlock/sun6i_hwspinlock.c210
4 files changed, 226 insertions, 0 deletions
diff --git a/MAINTAINERS b/MAINTAINERS
index bd7aff0c120f..6586747146db 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -745,6 +745,12 @@ L: linux-crypto@vger.kernel.org
S: Maintained
F: drivers/crypto/allwinner/
+ALLWINNER HARDWARE SPINLOCK SUPPORT
+M: Wilken Gottwalt <wilken.gottwalt@posteo.net>
+S: Maintained
+F: Documentation/devicetree/bindings/hwlock/allwinner,sun6i-hwspinlock.yaml
+F: drivers/hwspinlock/sun6i_hwspinlock.c
+
ALLWINNER THERMAL DRIVER
M: Vasily Khoruzhick <anarsoul@gmail.com>
M: Yangtao Li <tiny.windzz@gmail.com>
diff --git a/drivers/hwspinlock/Kconfig b/drivers/hwspinlock/Kconfig
index 53e13476e831..3874d15b0e9b 100644
--- a/drivers/hwspinlock/Kconfig
+++ b/drivers/hwspinlock/Kconfig
@@ -44,6 +44,15 @@ config HWSPINLOCK_STM32
If unsure, say N.
+config HWSPINLOCK_SUN6I
+ tristate "SUN6I Hardware Spinlock device"
+ depends on ARCH_SUNXI || COMPILE_TEST
+ help
+ Say y here to support the SUN6I Hardware Spinlock device which can be
+ found in most of the sun6i compatible Allwinner SoCs.
+
+ If unsure, say N.
+
config HSEM_U8500
tristate "STE Hardware Semaphore functionality"
depends on ARCH_U8500 || COMPILE_TEST
diff --git a/drivers/hwspinlock/Makefile b/drivers/hwspinlock/Makefile
index 1f8dd6f5814f..a0f16c9aaa82 100644
--- a/drivers/hwspinlock/Makefile
+++ b/drivers/hwspinlock/Makefile
@@ -8,4 +8,5 @@ obj-$(CONFIG_HWSPINLOCK_OMAP) += omap_hwspinlock.o
obj-$(CONFIG_HWSPINLOCK_QCOM) += qcom_hwspinlock.o
obj-$(CONFIG_HWSPINLOCK_SPRD) += sprd_hwspinlock.o
obj-$(CONFIG_HWSPINLOCK_STM32) += stm32_hwspinlock.o
+obj-$(CONFIG_HWSPINLOCK_SUN6I) += sun6i_hwspinlock.o
obj-$(CONFIG_HSEM_U8500) += u8500_hsem.o
diff --git a/drivers/hwspinlock/sun6i_hwspinlock.c b/drivers/hwspinlock/sun6i_hwspinlock.c
new file mode 100644
index 000000000000..c2d314588046
--- /dev/null
+++ b/drivers/hwspinlock/sun6i_hwspinlock.c
@@ -0,0 +1,210 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * sun6i_hwspinlock.c - hardware spinlock driver for sun6i compatible Allwinner SoCs
+ * Copyright (C) 2020 Wilken Gottwalt <wilken.gottwalt@posteo.net>
+ */
+
+#include <linux/clk.h>
+#include <linux/debugfs.h>
+#include <linux/errno.h>
+#include <linux/hwspinlock.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/reset.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/types.h>
+
+#include "hwspinlock_internal.h"
+
+#define DRIVER_NAME "sun6i_hwspinlock"
+
+#define SPINLOCK_BASE_ID 0 /* there is only one hwspinlock device per SoC */
+#define SPINLOCK_SYSSTATUS_REG 0x0000
+#define SPINLOCK_LOCK_REGN 0x0100
+#define SPINLOCK_NOTTAKEN 0
+
+struct sun6i_hwspinlock_data {
+ struct hwspinlock_device *bank;
+ struct reset_control *reset;
+ struct clk *ahb_clk;
+ struct dentry *debugfs;
+ int nlocks;
+};
+
+#ifdef CONFIG_DEBUG_FS
+
+static int hwlocks_supported_show(struct seq_file *seqf, void *unused)
+{
+ struct sun6i_hwspinlock_data *priv = seqf->private;
+
+ seq_printf(seqf, "%d\n", priv->nlocks);
+
+ return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(hwlocks_supported);
+
+static void sun6i_hwspinlock_debugfs_init(struct sun6i_hwspinlock_data *priv)
+{
+ priv->debugfs = debugfs_create_dir(DRIVER_NAME, NULL);
+ debugfs_create_file("supported", 0444, priv->debugfs, priv, &hwlocks_supported_fops);
+}
+
+#else
+
+static void sun6i_hwspinlock_debugfs_init(struct sun6i_hwspinlock_data *priv)
+{
+}
+
+#endif
+
+static int sun6i_hwspinlock_trylock(struct hwspinlock *lock)
+{
+ void __iomem *lock_addr = lock->priv;
+
+ return (readl(lock_addr) == SPINLOCK_NOTTAKEN);
+}
+
+static void sun6i_hwspinlock_unlock(struct hwspinlock *lock)
+{
+ void __iomem *lock_addr = lock->priv;
+
+ writel(SPINLOCK_NOTTAKEN, lock_addr);
+}
+
+static const struct hwspinlock_ops sun6i_hwspinlock_ops = {
+ .trylock = sun6i_hwspinlock_trylock,
+ .unlock = sun6i_hwspinlock_unlock,
+};
+
+static void sun6i_hwspinlock_disable(void *data)
+{
+ struct sun6i_hwspinlock_data *priv = data;
+
+ debugfs_remove_recursive(priv->debugfs);
+ clk_disable_unprepare(priv->ahb_clk);
+ reset_control_assert(priv->reset);
+}
+
+static int sun6i_hwspinlock_probe(struct platform_device *pdev)
+{
+ struct sun6i_hwspinlock_data *priv;
+ struct hwspinlock *hwlock;
+ void __iomem *io_base;
+ u32 num_banks;
+ int err, i;
+
+ io_base = devm_platform_ioremap_resource(pdev, SPINLOCK_BASE_ID);
+ if (IS_ERR(io_base))
+ return PTR_ERR(io_base);
+
+ priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ priv->ahb_clk = devm_clk_get(&pdev->dev, "ahb");
+ if (IS_ERR(priv->ahb_clk)) {
+ err = PTR_ERR(priv->ahb_clk);
+ dev_err(&pdev->dev, "unable to get AHB clock (%d)\n", err);
+ return err;
+ }
+
+ priv->reset = devm_reset_control_get(&pdev->dev, "ahb");
+ if (IS_ERR(priv->reset))
+ return dev_err_probe(&pdev->dev, PTR_ERR(priv->reset),
+ "unable to get reset control\n");
+
+ err = reset_control_deassert(priv->reset);
+ if (err) {
+ dev_err(&pdev->dev, "deassert reset control failure (%d)\n", err);
+ return err;
+ }
+
+ err = clk_prepare_enable(priv->ahb_clk);
+ if (err) {
+ dev_err(&pdev->dev, "unable to prepare AHB clk (%d)\n", err);
+ goto clk_fail;
+ }
+
+ /*
+ * bit 28 and 29 represents the hwspinlock setup
+ *
+ * every datasheet (A64, A80, A83T, H3, H5, H6 ...) says the default value is 0x1 and 0x1
+ * to 0x4 represent 32, 64, 128 and 256 locks
+ * but later datasheets (H5, H6) say 00, 01, 10, 11 represent 32, 64, 128 and 256 locks,
+ * but that would mean H5 and H6 have 64 locks, while their datasheets talk about 32 locks
+ * all the time, not a single mentioning of 64 locks
+ * the 0x4 value is also not representable by 2 bits alone, so some datasheets are not
+ * correct
+ * one thing have all in common, default value of the sysstatus register is 0x10000000,
+ * which results in bit 28 being set
+ * this is the reason 0x1 is considered being 32 locks and bit 30 is taken into account
+ * verified on H2+ (datasheet 0x1 = 32 locks) and H5 (datasheet 01 = 64 locks)
+ */
+ num_banks = readl(io_base + SPINLOCK_SYSSTATUS_REG) >> 28;
+ switch (num_banks) {
+ case 1 ... 4:
+ priv->nlocks = 1 << (4 + num_banks);
+ break;
+ default:
+ err = -EINVAL;
+ dev_err(&pdev->dev, "unsupported hwspinlock setup (%d)\n", num_banks);
+ goto bank_fail;
+ }
+
+ priv->bank = devm_kzalloc(&pdev->dev, struct_size(priv->bank, lock, priv->nlocks),
+ GFP_KERNEL);
+ if (!priv->bank) {
+ err = -ENOMEM;
+ goto bank_fail;
+ }
+
+ for (i = 0; i < priv->nlocks; ++i) {
+ hwlock = &priv->bank->lock[i];
+ hwlock->priv = io_base + SPINLOCK_LOCK_REGN + sizeof(u32) * i;
+ }
+
+ /* failure of debugfs is considered non-fatal */
+ sun6i_hwspinlock_debugfs_init(priv);
+ if (IS_ERR(priv->debugfs))
+ priv->debugfs = NULL;
+
+ err = devm_add_action_or_reset(&pdev->dev, sun6i_hwspinlock_disable, priv);
+ if (err) {
+ dev_err(&pdev->dev, "failed to add hwspinlock disable action\n");
+ goto bank_fail;
+ }
+
+ platform_set_drvdata(pdev, priv);
+
+ return devm_hwspin_lock_register(&pdev->dev, priv->bank, &sun6i_hwspinlock_ops,
+ SPINLOCK_BASE_ID, priv->nlocks);
+
+bank_fail:
+ clk_disable_unprepare(priv->ahb_clk);
+clk_fail:
+ reset_control_assert(priv->reset);
+
+ return err;
+}
+
+static const struct of_device_id sun6i_hwspinlock_ids[] = {
+ { .compatible = "allwinner,sun6i-a31-hwspinlock", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, sun6i_hwspinlock_ids);
+
+static struct platform_driver sun6i_hwspinlock_driver = {
+ .probe = sun6i_hwspinlock_probe,
+ .driver = {
+ .name = DRIVER_NAME,
+ .of_match_table = sun6i_hwspinlock_ids,
+ },
+};
+module_platform_driver(sun6i_hwspinlock_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("SUN6I hardware spinlock driver");
+MODULE_AUTHOR("Wilken Gottwalt <wilken.gottwalt@posteo.net>");