Merge tag 'reset-for-5.0-rc2' of git://git.pengutronix.de/git/pza/lin…

…ux into fixes

Late reset controller changes for v5.0

This adds missing deassert functionality to the ARC HSDK reset driver,
fixes some indentation and grammar issues in the kernel docs, adds a
helper to count the number of resets on a device for the non-DT case
as well, adds an early reset driver for SoCFPGA and simple reset driver
support for Stratix10, and generalizes the uniphier USB3 glue layer
reset to also cover AHCI.

* tag 'reset-for-5.0-rc2' of git://git.pengutronix.de/git/pza/linux:
  reset: uniphier-glue: Add AHCI reset control support in glue layer
  dt-bindings: reset: uniphier: Add AHCI core reset description
  reset: uniphier-usb3: Rename to reset-uniphier-glue
  dt-bindings: reset: uniphier: Replace the expression of USB3 with generic peripherals
  ARM: socfpga: dts: document "altr,stratix10-rst-mgr" binding
  reset: socfpga: add an early reset driver for SoCFPGA
  reset: fix null pointer dereference on dev by dev_name
  reset: Add reset_control_get_count()
  reset: Improve reset controller kernel docs
  ARC: HSDK: improve reset driver

Signed-off-by: Olof Johansson <[email protected]>

Documentation/devicetree/bindings/reset/socfpga-reset.txt

@@ -1,7 +1,8 @@
 Altera SOCFPGA Reset Manager
 
 Required properties:
-- compatible : "altr,rst-mgr"
+- compatible : "altr,rst-mgr" for (Cyclone5/Arria5/Arria10)
+	       "altr,stratix10-rst-mgr","altr,rst-mgr" for Stratix10 ARM64 SoC
 - reg : Should contain 1 register ranges(address and length)
 - altr,modrst-offset : Should contain the offset of the first modrst register.
 - #reset-cells: 1

Documentation/devicetree/bindings/reset/uniphier-reset.txt

@@ -120,27 +120,30 @@ Example:
 	};
 
 
-USB3 core reset
----------------
+Peripheral core reset in glue layer
+-----------------------------------
 
-USB3 core reset belongs to USB3 glue layer. Before using the core reset,
-it is necessary to control the clocks and resets to enable this layer.
-These clocks and resets should be described in each property.
+Some peripheral core reset belongs to its own glue layer. Before using
+this core reset, it is necessary to control the clocks and resets to enable
+this layer. These clocks and resets should be described in each property.
 
 Required properties:
 - compatible: Should be
-    "socionext,uniphier-pro4-usb3-reset" - for Pro4 SoC
-    "socionext,uniphier-pxs2-usb3-reset" - for PXs2 SoC
-    "socionext,uniphier-ld20-usb3-reset" - for LD20 SoC
-    "socionext,uniphier-pxs3-usb3-reset" - for PXs3 SoC
+    "socionext,uniphier-pro4-usb3-reset" - for Pro4 SoC USB3
+    "socionext,uniphier-pxs2-usb3-reset" - for PXs2 SoC USB3
+    "socionext,uniphier-ld20-usb3-reset" - for LD20 SoC USB3
+    "socionext,uniphier-pxs3-usb3-reset" - for PXs3 SoC USB3
+    "socionext,uniphier-pro4-ahci-reset" - for Pro4 SoC AHCI
+    "socionext,uniphier-pxs2-ahci-reset" - for PXs2 SoC AHCI
+    "socionext,uniphier-pxs3-ahci-reset" - for PXs3 SoC AHCI
 - #reset-cells: Should be 1.
 - reg: Specifies offset and length of the register set for the device.
-- clocks: A list of phandles to the clock gate for USB3 glue layer.
+- clocks: A list of phandles to the clock gate for the glue layer.
 	According to the clock-names, appropriate clocks are required.
 - clock-names: Should contain
     "gio", "link" - for Pro4 SoC
     "link"        - for others
-- resets: A list of phandles to the reset control for USB3 glue layer.
+- resets: A list of phandles to the reset control for the glue layer.
 	According to the reset-names, appropriate resets are required.
 - reset-names: Should contain
     "gio", "link" - for Pro4 SoC

arch/arm/mach-socfpga/socfpga.c

@@ -32,6 +32,8 @@ void __iomem *rst_manager_base_addr;
 void __iomem *sdr_ctl_base_addr;
 unsigned long socfpga_cpu1start_addr;
 
+extern void __init socfpga_reset_init(void);
+
 static void __init socfpga_sysmgr_init(void)
 {
 	struct device_node *np;
@@ -64,6 +66,7 @@ static void __init socfpga_init_irq(void)
 
 	if (IS_ENABLED(CONFIG_EDAC_ALTERA_OCRAM))
 		socfpga_init_ocram_ecc();
+	socfpga_reset_init();
 }
 
 static void __init socfpga_arria10_init_irq(void)
@@ -74,6 +77,7 @@ static void __init socfpga_arria10_init_irq(void)
 		socfpga_init_arria10_l2_ecc();
 	if (IS_ENABLED(CONFIG_EDAC_ALTERA_OCRAM))
 		socfpga_init_arria10_ocram_ecc();
+	socfpga_reset_init();
 }
 
 static void socfpga_cyclone5_restart(enum reboot_mode mode, const char *cmd)

drivers/reset/Kconfig

@@ -109,7 +109,7 @@ config RESET_QCOM_PDC
 
 config RESET_SIMPLE
 	bool "Simple Reset Controller Driver" if COMPILE_TEST
-	default ARCH_SOCFPGA || ARCH_STM32 || ARCH_STRATIX10 || ARCH_SUNXI || ARCH_ZX || ARCH_ASPEED
+	default ARCH_STM32 || ARCH_STRATIX10 || ARCH_SUNXI || ARCH_ZX || ARCH_ASPEED
 	help
 	  This enables a simple reset controller driver for reset lines that
 	  that can be asserted and deasserted by toggling bits in a contiguous,
@@ -128,6 +128,14 @@ config RESET_STM32MP157
 	help
 	  This enables the RCC reset controller driver for STM32 MPUs.
 
+config RESET_SOCFPGA
+	bool "SoCFPGA Reset Driver" if COMPILE_TEST && !ARCH_SOCFPGA
+	default ARCH_SOCFPGA
+	select RESET_SIMPLE
+	help
+	  This enables the reset driver for the SoCFPGA ARMv7 platforms. This
+	  driver gets initialized early during platform init calls.
+
 config RESET_SUNXI
 	bool "Allwinner SoCs Reset Driver" if COMPILE_TEST && !ARCH_SUNXI
 	default ARCH_SUNXI
@@ -163,15 +171,15 @@ config RESET_UNIPHIER
 	  Say Y if you want to control reset signals provided by System Control
 	  block, Media I/O block, Peripheral Block.
 
-config RESET_UNIPHIER_USB3
-	tristate "USB3 reset driver for UniPhier SoCs"
+config RESET_UNIPHIER_GLUE
+	tristate "Reset driver in glue layer for UniPhier SoCs"
 	depends on (ARCH_UNIPHIER || COMPILE_TEST) && OF
 	default ARCH_UNIPHIER
 	select RESET_SIMPLE
 	help
-	  Support for the USB3 core reset on UniPhier SoCs.
-	  Say Y if you want to control reset signals provided by
-	  USB3 glue layer.
+	  Support for peripheral core reset included in its own glue layer
+	  on UniPhier SoCs. Say Y if you want to control reset signals
+	  provided by the glue layer.
 
 config RESET_ZYNQ
 	bool "ZYNQ Reset Driver" if COMPILE_TEST

drivers/reset/Makefile

@@ -19,10 +19,11 @@ obj-$(CONFIG_RESET_QCOM_AOSS) += reset-qcom-aoss.o
 obj-$(CONFIG_RESET_QCOM_PDC) += reset-qcom-pdc.o
 obj-$(CONFIG_RESET_SIMPLE) += reset-simple.o
 obj-$(CONFIG_RESET_STM32MP157) += reset-stm32mp1.o
+obj-$(CONFIG_RESET_SOCFPGA) += reset-socfpga.o
 obj-$(CONFIG_RESET_SUNXI) += reset-sunxi.o
 obj-$(CONFIG_RESET_TI_SCI) += reset-ti-sci.o
 obj-$(CONFIG_RESET_TI_SYSCON) += reset-ti-syscon.o
 obj-$(CONFIG_RESET_UNIPHIER) += reset-uniphier.o
-obj-$(CONFIG_RESET_UNIPHIER_USB3) += reset-uniphier-usb3.o
+obj-$(CONFIG_RESET_UNIPHIER_GLUE) += reset-uniphier-glue.o
 obj-$(CONFIG_RESET_ZYNQ) += reset-zynq.o
 

drivers/reset/core.c

@@ -795,3 +795,45 @@ devm_reset_control_array_get(struct device *dev, bool shared, bool optional)
 	return rstc;
 }
 EXPORT_SYMBOL_GPL(devm_reset_control_array_get);
+
+static int reset_control_get_count_from_lookup(struct device *dev)
+{
+	const struct reset_control_lookup *lookup;
+	const char *dev_id;
+	int count = 0;
+
+	if (!dev)
+		return -EINVAL;
+
+	dev_id = dev_name(dev);
+	mutex_lock(&reset_lookup_mutex);
+
+	list_for_each_entry(lookup, &reset_lookup_list, list) {
+		if (!strcmp(lookup->dev_id, dev_id))
+			count++;
+	}
+
+	mutex_unlock(&reset_lookup_mutex);
+
+	if (count == 0)
+		count = -ENOENT;
+
+	return count;
+}
+
+/**
+ * reset_control_get_count - Count number of resets available with a device
+ *
+ * @dev: device for which to return the number of resets
+ *
+ * Returns positive reset count on success, or error number on failure and
+ * on count being zero.
+ */
+int reset_control_get_count(struct device *dev)
+{
+	if (dev->of_node)
+		return of_reset_control_get_count(dev->of_node);
+
+	return reset_control_get_count_from_lookup(dev);
+}
+EXPORT_SYMBOL_GPL(reset_control_get_count);

drivers/reset/reset-hsdk.c

@@ -86,6 +86,7 @@ static int hsdk_reset_reset(struct reset_controller_dev *rcdev,
 
 static const struct reset_control_ops hsdk_reset_ops = {
 	.reset	= hsdk_reset_reset,
+	.deassert = hsdk_reset_reset,
 };
 
 static int hsdk_reset_probe(struct platform_device *pdev)

drivers/reset/reset-simple.c

@@ -109,7 +109,7 @@ struct reset_simple_devdata {
 #define SOCFPGA_NR_BANKS	8
 
 static const struct reset_simple_devdata reset_simple_socfpga = {
-	.reg_offset = 0x10,
+	.reg_offset = 0x20,
 	.nr_resets = SOCFPGA_NR_BANKS * 32,
 	.status_active_low = true,
 };
@@ -120,7 +120,8 @@ static const struct reset_simple_devdata reset_simple_active_low = {
 };
 
 static const struct of_device_id reset_simple_dt_ids[] = {
-	{ .compatible = "altr,rst-mgr", .data = &reset_simple_socfpga },
+	{ .compatible = "altr,stratix10-rst-mgr",
+		.data = &reset_simple_socfpga },
 	{ .compatible = "st,stm32-rcc", },
 	{ .compatible = "allwinner,sun6i-a31-clock-reset",
 		.data = &reset_simple_active_low },
@@ -166,14 +167,6 @@ static int reset_simple_probe(struct platform_device *pdev)
 		data->status_active_low = devdata->status_active_low;
 	}
 
-	if (of_device_is_compatible(dev->of_node, "altr,rst-mgr") &&
-	    of_property_read_u32(dev->of_node, "altr,modrst-offset",
-				 &reg_offset)) {
-		dev_warn(dev,
-			 "missing altr,modrst-offset property, assuming 0x%x!\n",
-			 reg_offset);
-	}
-
 	data->membase += reg_offset;
 
 	return devm_reset_controller_register(dev, &data->rcdev);

drivers/reset/reset-socfpga.c

@@ -0,0 +1,88 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2018, Intel Corporation
+ * Copied from reset-sunxi.c
+ */
+
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/init.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/platform_device.h>
+#include <linux/reset-controller.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/types.h>
+
+#include "reset-simple.h"
+
+#define SOCFPGA_NR_BANKS	8
+void __init socfpga_reset_init(void);
+
+static int a10_reset_init(struct device_node *np)
+{
+	struct reset_simple_data *data;
+	struct resource res;
+	resource_size_t size;
+	int ret;
+	u32 reg_offset = 0x10;
+
+	data = kzalloc(sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	ret = of_address_to_resource(np, 0, &res);
+	if (ret)
+		goto err_alloc;
+
+	size = resource_size(&res);
+	if (!request_mem_region(res.start, size, np->name)) {
+		ret = -EBUSY;
+		goto err_alloc;
+	}
+
+	data->membase = ioremap(res.start, size);
+	if (!data->membase) {
+		ret = -ENOMEM;
+		goto err_alloc;
+	}
+
+	if (of_property_read_u32(np, "altr,modrst-offset", &reg_offset))
+		pr_warn("missing altr,modrst-offset property, assuming 0x10\n");
+	data->membase += reg_offset;
+
+	spin_lock_init(&data->lock);
+
+	data->rcdev.owner = THIS_MODULE;
+	data->rcdev.nr_resets = SOCFPGA_NR_BANKS * 32;
+	data->rcdev.ops = &reset_simple_ops;
+	data->rcdev.of_node = np;
+	data->status_active_low = true;
+
+	return reset_controller_register(&data->rcdev);
+
+err_alloc:
+	kfree(data);
+	return ret;
+};
+
+/*
+ * These are the reset controller we need to initialize early on in
+ * our system, before we can even think of using a regular device
+ * driver for it.
+ * The controllers that we can register through the regular device
+ * model are handled by the simple reset driver directly.
+ */
+static const struct of_device_id socfpga_early_reset_dt_ids[] __initconst = {
+	{ .compatible = "altr,rst-mgr", },
+	{ /* sentinel */ },
+};
+
+void __init socfpga_reset_init(void)
+{
+	struct device_node *np;
+
+	for_each_matching_node(np, socfpga_early_reset_dt_ids)
+		a10_reset_init(np);
+}