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authorLinus Torvalds <torvalds@linux-foundation.org>2021-02-26 21:28:35 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2021-02-26 21:28:35 +0300
commit8b83369ddcb3fb9cab5c1088987ce477565bb630 (patch)
tree825b1bc89bf731c15c5463befe4e9f14870f0811 /drivers/reset
parent8f47d753d4ecc6d3e306e22d885d6772625a3423 (diff)
parentd7fbcf40df86bb67193d9faf52138fc1202decb2 (diff)
downloadlinux-8b83369ddcb3fb9cab5c1088987ce477565bb630.tar.xz
Merge tag 'riscv-for-linus-5.12-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux
Pull RISC-V updates from Palmer Dabbelt: "A handful of new RISC-V related patches for this merge window: - A check to ensure drivers are properly using uaccess. This isn't manifesting with any of the drivers I'm currently using, but may catch errors in new drivers. - Some preliminary support for the FU740, along with the HiFive Unleashed it will appear on. - NUMA support for RISC-V, which involves making the arm64 code generic. - Support for kasan on the vmalloc region. - A handful of new drivers for the Kendryte K210, along with the DT plumbing required to boot on a handful of K210-based boards. - Support for allocating ASIDs. - Preliminary support for kernels larger than 128MiB. - Various other improvements to our KASAN support, including the utilization of huge pages when allocating the KASAN regions. We may have already found a bug with the KASAN_VMALLOC code, but it's passing my tests. There's a fix in the works, but that will probably miss the merge window. * tag 'riscv-for-linus-5.12-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (75 commits) riscv: Improve kasan population by using hugepages when possible riscv: Improve kasan population function riscv: Use KASAN_SHADOW_INIT define for kasan memory initialization riscv: Improve kasan definitions riscv: Get rid of MAX_EARLY_MAPPING_SIZE soc: canaan: Sort the Makefile alphabetically riscv: Disable KSAN_SANITIZE for vDSO riscv: Remove unnecessary declaration riscv: Add Canaan Kendryte K210 SD card defconfig riscv: Update Canaan Kendryte K210 defconfig riscv: Add Kendryte KD233 board device tree riscv: Add SiPeed MAIXDUINO board device tree riscv: Add SiPeed MAIX GO board device tree riscv: Add SiPeed MAIX DOCK board device tree riscv: Add SiPeed MAIX BiT board device tree riscv: Update Canaan Kendryte K210 device tree dt-bindings: add resets property to dw-apb-timer dt-bindings: fix sifive gpio properties dt-bindings: update sifive uart compatible string dt-bindings: update sifive clint compatible string ...
Diffstat (limited to 'drivers/reset')
-rw-r--r--drivers/reset/Kconfig10
-rw-r--r--drivers/reset/Makefile1
-rw-r--r--drivers/reset/reset-k210.c131
3 files changed, 142 insertions, 0 deletions
diff --git a/drivers/reset/Kconfig b/drivers/reset/Kconfig
index 8ac5627564f0..4171c6f76385 100644
--- a/drivers/reset/Kconfig
+++ b/drivers/reset/Kconfig
@@ -89,6 +89,16 @@ config RESET_INTEL_GW
Say Y to control the reset signals provided by reset controller.
Otherwise, say N.
+config RESET_K210
+ bool "Reset controller driver for Canaan Kendryte K210 SoC"
+ depends on (SOC_CANAAN || COMPILE_TEST) && OF
+ select MFD_SYSCON
+ default SOC_CANAAN
+ help
+ Support for the Canaan Kendryte K210 RISC-V SoC reset controller.
+ Say Y if you want to control reset signals provided by this
+ controller.
+
config RESET_LANTIQ
bool "Lantiq XWAY Reset Driver" if COMPILE_TEST
default SOC_TYPE_XWAY
diff --git a/drivers/reset/Makefile b/drivers/reset/Makefile
index 1054123fd187..65a118a91b27 100644
--- a/drivers/reset/Makefile
+++ b/drivers/reset/Makefile
@@ -13,6 +13,7 @@ obj-$(CONFIG_RESET_BRCMSTB_RESCAL) += reset-brcmstb-rescal.o
obj-$(CONFIG_RESET_HSDK) += reset-hsdk.o
obj-$(CONFIG_RESET_IMX7) += reset-imx7.o
obj-$(CONFIG_RESET_INTEL_GW) += reset-intel-gw.o
+obj-$(CONFIG_RESET_K210) += reset-k210.o
obj-$(CONFIG_RESET_LANTIQ) += reset-lantiq.o
obj-$(CONFIG_RESET_LPC18XX) += reset-lpc18xx.o
obj-$(CONFIG_RESET_MESON) += reset-meson.o
diff --git a/drivers/reset/reset-k210.c b/drivers/reset/reset-k210.c
new file mode 100644
index 000000000000..1b6e03522b40
--- /dev/null
+++ b/drivers/reset/reset-k210.c
@@ -0,0 +1,131 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) 2020 Western Digital Corporation or its affiliates.
+ */
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/reset-controller.h>
+#include <linux/delay.h>
+#include <linux/mfd/syscon.h>
+#include <linux/regmap.h>
+#include <soc/canaan/k210-sysctl.h>
+
+#include <dt-bindings/reset/k210-rst.h>
+
+#define K210_RST_MASK 0x27FFFFFF
+
+struct k210_rst {
+ struct regmap *map;
+ struct reset_controller_dev rcdev;
+};
+
+static inline struct k210_rst *
+to_k210_rst(struct reset_controller_dev *rcdev)
+{
+ return container_of(rcdev, struct k210_rst, rcdev);
+}
+
+static inline int k210_rst_assert(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ struct k210_rst *ksr = to_k210_rst(rcdev);
+
+ return regmap_update_bits(ksr->map, K210_SYSCTL_PERI_RESET, BIT(id), 1);
+}
+
+static inline int k210_rst_deassert(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ struct k210_rst *ksr = to_k210_rst(rcdev);
+
+ return regmap_update_bits(ksr->map, K210_SYSCTL_PERI_RESET, BIT(id), 0);
+}
+
+static int k210_rst_reset(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ int ret;
+
+ ret = k210_rst_assert(rcdev, id);
+ if (ret == 0) {
+ udelay(10);
+ ret = k210_rst_deassert(rcdev, id);
+ }
+
+ return ret;
+}
+
+static int k210_rst_status(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ struct k210_rst *ksr = to_k210_rst(rcdev);
+ u32 reg, bit = BIT(id);
+ int ret;
+
+ ret = regmap_read(ksr->map, K210_SYSCTL_PERI_RESET, &reg);
+ if (ret)
+ return ret;
+
+ return reg & bit;
+}
+
+static int k210_rst_xlate(struct reset_controller_dev *rcdev,
+ const struct of_phandle_args *reset_spec)
+{
+ unsigned long id = reset_spec->args[0];
+
+ if (!(BIT(id) & K210_RST_MASK))
+ return -EINVAL;
+
+ return id;
+}
+
+static const struct reset_control_ops k210_rst_ops = {
+ .assert = k210_rst_assert,
+ .deassert = k210_rst_deassert,
+ .reset = k210_rst_reset,
+ .status = k210_rst_status,
+};
+
+static int k210_rst_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct device_node *parent_np = of_get_parent(dev->of_node);
+ struct k210_rst *ksr;
+
+ dev_info(dev, "K210 reset controller\n");
+
+ ksr = devm_kzalloc(dev, sizeof(*ksr), GFP_KERNEL);
+ if (!ksr)
+ return -ENOMEM;
+
+ ksr->map = syscon_node_to_regmap(parent_np);
+ of_node_put(parent_np);
+ if (IS_ERR(ksr->map))
+ return PTR_ERR(ksr->map);
+
+ ksr->rcdev.owner = THIS_MODULE;
+ ksr->rcdev.dev = dev;
+ ksr->rcdev.of_node = dev->of_node;
+ ksr->rcdev.ops = &k210_rst_ops;
+ ksr->rcdev.nr_resets = fls(K210_RST_MASK);
+ ksr->rcdev.of_reset_n_cells = 1;
+ ksr->rcdev.of_xlate = k210_rst_xlate;
+
+ return devm_reset_controller_register(dev, &ksr->rcdev);
+}
+
+static const struct of_device_id k210_rst_dt_ids[] = {
+ { .compatible = "canaan,k210-rst" },
+ { /* sentinel */ },
+};
+
+static struct platform_driver k210_rst_driver = {
+ .probe = k210_rst_probe,
+ .driver = {
+ .name = "k210-rst",
+ .of_match_table = k210_rst_dt_ids,
+ },
+};
+builtin_platform_driver(k210_rst_driver);