Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Fix error output of boot instance creation failure

   Currently if a boot instance creation fails, instead of printing out
   the name of the instance that failed, it prints "(null)". That is
   because it prints "cur_str" that had already been processed by
   strsep(). Print the saved name instead.

   While at it, print the error code of the failure.

 - Fix use-after-free for same named historgrams

   Histograms can be named so that they can be used in multiple events.
   But if the named histogram has a variable attached, the second event
   that uses the named histogram which duplicates it and needs to free
   the original after duplication leaves the old variable in place and
   still visible. If another histogram uses than variable, it will use
   the stale one which will try to reference the freed duplicate
   histogram and crash the kernel.

   Free the duplicate variables along with the duplicated histogram
   data.

 - Check return value of kthread_run() in event self test

   The events self tests uses a kthread for testing but does not check
   if it succeeded in creating a kthread. If the kthread creation were
   to fail, the code will still try to call kthread_stop() on the error
   returned.

 - Fix race between reading trace_pipe and updating subbuffer size

   If a user is reading the trace_pipe file at the same time they update
   the ring buffer sub-buffer size, can cause the trace_pipe read to
   read stale data. Add trace_access_lock() around updating the ring
   buffer sub-buffer size.

 - Fix eventfs_inode on failure path in creation of the events directory

   In the creation of the "events" directory, if after allocating the
   eventfs_inode a failure is detected, it calls cleanup_ei() which
   calls free_ei(). The free_ei() will test if eventfs_inode being freed
   has no children. It is a bug if it does. But on the failure case of
   the creation of the "events" directory, the children lists have not
   yet been initialized and the free will trigger a warning because
   list_empty() on an uninitialized list returns false.

   Move the initialization into init_ei() where it makes more sense and
   makes sure that a created eventfs_inode has its lists initialized
   upon creation.

 - Check return value of kthread_run() in ftrace direct sample code

   The sample code that shows how to use the ftrace direct calls does
   not test the return of kthread_run() to see if it succeeds. Return a
   failure if the kthread_run() doesn't succeed.

 - Clear user events state on fork in case of alloc failure

   On fork, the child gets a pointer to the parent's user events state.
   It makes a copy of it then updates the child's pointer to it. But if
   the allocation fails, the duplication function leaves the child with
   a pointer to its parent's descriptor. When the child cleans up its
   data, it will free the parent's descriptor while the parent is still
   using it.

   In the duplication function, set the child's user_event_mm to NULL
   before testing if the allocation succeeded, and when it exits it will
   not free the parent's descriptor.

 - Fix retry exhaustion in simple ring buffer reader swap

   simple_ring_buffer_swap_reader_page() starts with retry set to 8 and
   post-decrements it only after a failed link replacement. On the final
   attempt, a successful replacement leaves retry at zero, while a
   failed replacement leaves it at -1.

   But the check for success expects the retry value to be non-zero and
   exits with an error on zero. This is the opposite result. Fix it.

 - Fail nicely when the remote swap_reader_page() returns an error

   Currently, if the swap_reader_page() of a remote buffer fails, it
   triggers a WARN_ON_ONCE() and continues normally. Instead, have it
   exit with an error and a pr_warn() print instead of a full WARNING.

* tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ring-buffer: Stop remote reader update when page swap fails
  tracing: Fix retry exhaustion in simple ring buffer reader swap
  tracing/user_events: Clear copied tracing state before fork duplication
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify
  eventfs: Initialize ei->children and ei->list in init_ei()
  tracing: Fix use-after-free in trace_pipe read on sub-buffer order change
  tracing: Fix crash passing ERR_PTR to kthread_stop()
  tracing: Fix use-after-free with same-name named triggers
  tracing: Fix logged instance name on creation failure

1 files changed, 460 insertions, 0 deletions

diff --git a/drivers/clk/clk-gemini.c b/drivers/clk/clk-gemini.c
new file mode 100644
index 000000000..9c0e6e7a7
--- /dev/null
+++ b/drivers/clk/clk-gemini.c
@@ -0,0 +1,460 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Cortina Gemini SoC Clock Controller driver
+ * Copyright (c) 2017 Linus Walleij <linus.walleij@linaro.org>
+ */
+
+#define pr_fmt(fmt) "clk-gemini: " fmt
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/clk-provider.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/mfd/syscon.h>
+#include <linux/regmap.h>
+#include <linux/spinlock.h>
+#include <linux/reset-controller.h>
+#include <dt-bindings/reset/cortina,gemini-reset.h>
+#include <dt-bindings/clock/cortina,gemini-clock.h>
+
+/* Globally visible clocks */
+static DEFINE_SPINLOCK(gemini_clk_lock);
+
+#define GEMINI_GLOBAL_STATUS		0x04
+#define PLL_OSC_SEL			BIT(30)
+#define AHBSPEED_SHIFT			(15)
+#define AHBSPEED_MASK			0x07
+#define CPU_AHB_RATIO_SHIFT		(18)
+#define CPU_AHB_RATIO_MASK		0x03
+
+#define GEMINI_GLOBAL_PLL_CONTROL	0x08
+
+#define GEMINI_GLOBAL_SOFT_RESET	0x0c
+
+#define GEMINI_GLOBAL_MISC_CONTROL	0x30
+#define PCI_CLK_66MHZ			BIT(18)
+
+#define GEMINI_GLOBAL_CLOCK_CONTROL	0x34
+#define PCI_CLKRUN_EN			BIT(16)
+#define TVC_HALFDIV_SHIFT		(24)
+#define TVC_HALFDIV_MASK		0x1f
+#define SECURITY_CLK_SEL		BIT(29)
+
+#define GEMINI_GLOBAL_PCI_DLL_CONTROL	0x44
+#define PCI_DLL_BYPASS			BIT(31)
+#define PCI_DLL_TAP_SEL_MASK		0x1f
+
+/**
+ * struct gemini_gate_data - Gemini gated clocks
+ * @bit_idx: the bit used to gate this clock in the clock register
+ * @name: the clock name
+ * @parent_name: the name of the parent clock
+ * @flags: standard clock framework flags
+ */
+struct gemini_gate_data {
+	u8 bit_idx;
+	const char *name;
+	const char *parent_name;
+	unsigned long flags;
+};
+
+/**
+ * struct clk_gemini_pci - Gemini PCI clock
+ * @hw: corresponding clock hardware entry
+ * @map: regmap to access the registers
+ */
+struct clk_gemini_pci {
+	struct clk_hw hw;
+	struct regmap *map;
+};
+
+/**
+ * struct gemini_reset - gemini reset controller
+ * @map: regmap to access the containing system controller
+ * @rcdev: reset controller device
+ */
+struct gemini_reset {
+	struct regmap *map;
+	struct reset_controller_dev rcdev;
+};
+
+/* Keeps track of all clocks */
+static struct clk_hw_onecell_data *gemini_clk_data;
+
+static const struct gemini_gate_data gemini_gates[] = {
+	{ 1, "security-gate", "secdiv", 0 },
+	{ 2, "gmac0-gate", "ahb", 0 },
+	{ 3, "gmac1-gate", "ahb", 0 },
+	{ 4, "sata0-gate", "ahb", 0 },
+	{ 5, "sata1-gate", "ahb", 0 },
+	{ 6, "usb0-gate", "ahb", 0 },
+	{ 7, "usb1-gate", "ahb", 0 },
+	{ 8, "ide-gate", "ahb", 0 },
+	{ 9, "pci-gate", "ahb", 0 },
+	/*
+	 * The DDR controller may never have a driver, but certainly must
+	 * not be gated off.
+	 */
+	{ 10, "ddr-gate", "ahb", CLK_IS_CRITICAL },
+	/*
+	 * The flash controller must be on to access NOR flash through the
+	 * memory map.
+	 */
+	{ 11, "flash-gate", "ahb", CLK_IGNORE_UNUSED },
+	{ 12, "tvc-gate", "ahb", 0 },
+	{ 13, "boot-gate", "apb", 0 },
+};
+
+#define to_pciclk(_hw) container_of(_hw, struct clk_gemini_pci, hw)
+
+#define to_gemini_reset(p) container_of((p), struct gemini_reset, rcdev)
+
+static unsigned long gemini_pci_recalc_rate(struct clk_hw *hw,
+					    unsigned long parent_rate)
+{
+	struct clk_gemini_pci *pciclk = to_pciclk(hw);
+	u32 val;
+
+	regmap_read(pciclk->map, GEMINI_GLOBAL_MISC_CONTROL, &val);
+	if (val & PCI_CLK_66MHZ)
+		return 66000000;
+	return 33000000;
+}
+
+static int gemini_pci_determine_rate(struct clk_hw *hw,
+				     struct clk_rate_request *req)
+{
+	/* We support 33 and 66 MHz */
+	if (req->rate < 48000000)
+		req->rate = 33000000;
+	else
+		req->rate = 66000000;
+
+	return 0;
+}
+
+static int gemini_pci_set_rate(struct clk_hw *hw, unsigned long rate,
+			       unsigned long parent_rate)
+{
+	struct clk_gemini_pci *pciclk = to_pciclk(hw);
+
+	if (rate == 33000000)
+		return regmap_update_bits(pciclk->map,
+					  GEMINI_GLOBAL_MISC_CONTROL,
+					  PCI_CLK_66MHZ, 0);
+	if (rate == 66000000)
+		return regmap_update_bits(pciclk->map,
+					  GEMINI_GLOBAL_MISC_CONTROL,
+					  0, PCI_CLK_66MHZ);
+	return -EINVAL;
+}
+
+static int gemini_pci_enable(struct clk_hw *hw)
+{
+	struct clk_gemini_pci *pciclk = to_pciclk(hw);
+
+	regmap_update_bits(pciclk->map, GEMINI_GLOBAL_CLOCK_CONTROL,
+			   0, PCI_CLKRUN_EN);
+	return 0;
+}
+
+static void gemini_pci_disable(struct clk_hw *hw)
+{
+	struct clk_gemini_pci *pciclk = to_pciclk(hw);
+
+	regmap_update_bits(pciclk->map, GEMINI_GLOBAL_CLOCK_CONTROL,
+			   PCI_CLKRUN_EN, 0);
+}
+
+static int gemini_pci_is_enabled(struct clk_hw *hw)
+{
+	struct clk_gemini_pci *pciclk = to_pciclk(hw);
+	unsigned int val;
+
+	regmap_read(pciclk->map, GEMINI_GLOBAL_CLOCK_CONTROL, &val);
+	return !!(val & PCI_CLKRUN_EN);
+}
+
+static const struct clk_ops gemini_pci_clk_ops = {
+	.recalc_rate = gemini_pci_recalc_rate,
+	.determine_rate = gemini_pci_determine_rate,
+	.set_rate = gemini_pci_set_rate,
+	.enable = gemini_pci_enable,
+	.disable = gemini_pci_disable,
+	.is_enabled = gemini_pci_is_enabled,
+};
+
+static struct clk_hw *gemini_pci_clk_setup(const char *name,
+					   const char *parent_name,
+					   struct regmap *map)
+{
+	struct clk_gemini_pci *pciclk;
+	struct clk_init_data init;
+	int ret;
+
+	pciclk = kzalloc_obj(*pciclk);
+	if (!pciclk)
+		return ERR_PTR(-ENOMEM);
+
+	init.name = name;
+	init.ops = &gemini_pci_clk_ops;
+	init.flags = 0;
+	init.parent_names = &parent_name;
+	init.num_parents = 1;
+	pciclk->map = map;
+	pciclk->hw.init = &init;
+
+	ret = clk_hw_register(NULL, &pciclk->hw);
+	if (ret) {
+		kfree(pciclk);
+		return ERR_PTR(ret);
+	}
+
+	return &pciclk->hw;
+}
+
+/*
+ * This is a self-deasserting reset controller.
+ */
+static int gemini_reset(struct reset_controller_dev *rcdev,
+			unsigned long id)
+{
+	struct gemini_reset *gr = to_gemini_reset(rcdev);
+
+	/* Manual says to always set BIT 30 (CPU1) to 1 */
+	return regmap_write(gr->map,
+			    GEMINI_GLOBAL_SOFT_RESET,
+			    BIT(GEMINI_RESET_CPU1) | BIT(id));
+}
+
+static int gemini_reset_assert(struct reset_controller_dev *rcdev,
+			       unsigned long id)
+{
+	return 0;
+}
+
+static int gemini_reset_deassert(struct reset_controller_dev *rcdev,
+				 unsigned long id)
+{
+	return 0;
+}
+
+static int gemini_reset_status(struct reset_controller_dev *rcdev,
+			     unsigned long id)
+{
+	struct gemini_reset *gr = to_gemini_reset(rcdev);
+	u32 val;
+	int ret;
+
+	ret = regmap_read(gr->map, GEMINI_GLOBAL_SOFT_RESET, &val);
+	if (ret)
+		return ret;
+
+	return !!(val & BIT(id));
+}
+
+static const struct reset_control_ops gemini_reset_ops = {
+	.reset = gemini_reset,
+	.assert = gemini_reset_assert,
+	.deassert = gemini_reset_deassert,
+	.status = gemini_reset_status,
+};
+
+static int gemini_clk_probe(struct platform_device *pdev)
+{
+	/* Gives the fracions 1x, 1.5x, 1.85x and 2x */
+	unsigned int cpu_ahb_mult[4] = { 1, 3, 24, 2 };
+	unsigned int cpu_ahb_div[4] = { 1, 2, 13, 1 };
+	void __iomem *base;
+	struct gemini_reset *gr;
+	struct regmap *map;
+	struct clk_hw *hw;
+	struct device *dev = &pdev->dev;
+	struct device_node *np = dev->of_node;
+	unsigned int mult, div;
+	u32 val;
+	int ret;
+	int i;
+
+	gr = devm_kzalloc(dev, sizeof(*gr), GFP_KERNEL);
+	if (!gr)
+		return -ENOMEM;
+
+	/* Remap the system controller for the exclusive register */
+	base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(base))
+		return PTR_ERR(base);
+
+	map = syscon_node_to_regmap(np);
+	if (IS_ERR(map)) {
+		dev_err(dev, "no syscon regmap\n");
+		return PTR_ERR(map);
+	}
+
+	gr->map = map;
+	gr->rcdev.owner = THIS_MODULE;
+	gr->rcdev.nr_resets = 32;
+	gr->rcdev.ops = &gemini_reset_ops;
+	gr->rcdev.of_node = np;
+
+	ret = devm_reset_controller_register(dev, &gr->rcdev);
+	if (ret) {
+		dev_err(dev, "could not register reset controller\n");
+		return ret;
+	}
+
+	/* RTC clock 32768 Hz */
+	hw = clk_hw_register_fixed_rate(NULL, "rtc", NULL, 0, 32768);
+	gemini_clk_data->hws[GEMINI_CLK_RTC] = hw;
+
+	/* CPU clock derived as a fixed ratio from the AHB clock */
+	regmap_read(map, GEMINI_GLOBAL_STATUS, &val);
+	val >>= CPU_AHB_RATIO_SHIFT;
+	val &= CPU_AHB_RATIO_MASK;
+	hw = clk_hw_register_fixed_factor(NULL, "cpu", "ahb", 0,
+					  cpu_ahb_mult[val],
+					  cpu_ahb_div[val]);
+	gemini_clk_data->hws[GEMINI_CLK_CPU] = hw;
+
+	/* Security clock is 1:1 or 0.75 of APB */
+	regmap_read(map, GEMINI_GLOBAL_CLOCK_CONTROL, &val);
+	if (val & SECURITY_CLK_SEL) {
+		mult = 1;
+		div = 1;
+	} else {
+		mult = 3;
+		div = 4;
+	}
+	hw = clk_hw_register_fixed_factor(NULL, "secdiv", "ahb", 0, mult, div);
+
+	/*
+	 * These are the leaf gates, at boot no clocks are gated.
+	 */
+	for (i = 0; i < ARRAY_SIZE(gemini_gates); i++) {
+		const struct gemini_gate_data *gd;
+
+		gd = &gemini_gates[i];
+		gemini_clk_data->hws[GEMINI_CLK_GATES + i] =
+			clk_hw_register_gate(NULL, gd->name,
+					     gd->parent_name,
+					     gd->flags,
+					     base + GEMINI_GLOBAL_CLOCK_CONTROL,
+					     gd->bit_idx,
+					     CLK_GATE_SET_TO_DISABLE,
+					     &gemini_clk_lock);
+	}
+
+	/*
+	 * The TV Interface Controller has a 5-bit half divider register.
+	 * This clock is supposed to be 27MHz as this is an exact multiple
+	 * of PAL and NTSC frequencies. The register is undocumented :(
+	 * FIXME: figure out the parent and how the divider works.
+	 */
+	mult = 1;
+	div = ((val >> TVC_HALFDIV_SHIFT) & TVC_HALFDIV_MASK);
+	dev_dbg(dev, "TVC half divider value = %d\n", div);
+	div += 1;
+	hw = clk_hw_register_fixed_rate(NULL, "tvcdiv", "xtal", 0, 27000000);
+	gemini_clk_data->hws[GEMINI_CLK_TVC] = hw;
+
+	/* FIXME: very unclear what the parent is */
+	hw = gemini_pci_clk_setup("PCI", "xtal", map);
+	gemini_clk_data->hws[GEMINI_CLK_PCI] = hw;
+
+	/* FIXME: very unclear what the parent is */
+	hw = clk_hw_register_fixed_rate(NULL, "uart", "xtal", 0, 48000000);
+	gemini_clk_data->hws[GEMINI_CLK_UART] = hw;
+
+	return 0;
+}
+
+static const struct of_device_id gemini_clk_dt_ids[] = {
+	{ .compatible = "cortina,gemini-syscon", },
+	{ /* sentinel */ },
+};
+
+static struct platform_driver gemini_clk_driver = {
+	.probe  = gemini_clk_probe,
+	.driver = {
+		.name = "gemini-clk",
+		.of_match_table = gemini_clk_dt_ids,
+		.suppress_bind_attrs = true,
+	},
+};
+builtin_platform_driver(gemini_clk_driver);
+
+static void __init gemini_cc_init(struct device_node *np)
+{
+	struct regmap *map;
+	struct clk_hw *hw;
+	unsigned long freq;
+	unsigned int mult, div;
+	u32 val;
+	int ret;
+	int i;
+
+	gemini_clk_data = kzalloc_flex(*gemini_clk_data, hws, GEMINI_NUM_CLKS);
+	if (!gemini_clk_data)
+		return;
+	gemini_clk_data->num = GEMINI_NUM_CLKS;
+
+	/*
+	 * This way all clock fetched before the platform device probes,
+	 * except those we assign here for early use, will be deferred.
+	 */
+	for (i = 0; i < GEMINI_NUM_CLKS; i++)
+		gemini_clk_data->hws[i] = ERR_PTR(-EPROBE_DEFER);
+
+	map = syscon_node_to_regmap(np);
+	if (IS_ERR(map)) {
+		pr_err("no syscon regmap\n");
+		return;
+	}
+	/*
+	 * We check that the regmap works on this very first access,
+	 * but as this is an MMIO-backed regmap, subsequent regmap
+	 * access is not going to fail and we skip error checks from
+	 * this point.
+	 */
+	ret = regmap_read(map, GEMINI_GLOBAL_STATUS, &val);
+	if (ret) {
+		pr_err("failed to read global status register\n");
+		return;
+	}
+
+	/*
+	 * XTAL is the crystal oscillator, 60 or 30 MHz selected from
+	 * strap pin E6
+	 */
+	if (val & PLL_OSC_SEL)
+		freq = 30000000;
+	else
+		freq = 60000000;
+	hw = clk_hw_register_fixed_rate(NULL, "xtal", NULL, 0, freq);
+	pr_debug("main crystal @%lu MHz\n", freq / 1000000);
+
+	/* VCO clock derived from the crystal */
+	mult = 13 + ((val >> AHBSPEED_SHIFT) & AHBSPEED_MASK);
+	div = 2;
+	/* If we run on 30 MHz crystal we have to multiply with two */
+	if (val & PLL_OSC_SEL)
+		mult *= 2;
+	hw = clk_hw_register_fixed_factor(NULL, "vco", "xtal", 0, mult, div);
+
+	/* The AHB clock is always 1/3 of the VCO */
+	hw = clk_hw_register_fixed_factor(NULL, "ahb", "vco", 0, 1, 3);
+	gemini_clk_data->hws[GEMINI_CLK_AHB] = hw;
+
+	/* The APB clock is always 1/6 of the AHB */
+	hw = clk_hw_register_fixed_factor(NULL, "apb", "ahb", 0, 1, 6);
+	gemini_clk_data->hws[GEMINI_CLK_APB] = hw;
+
+	/* Register the clocks to be accessed by the device tree */
+	of_clk_add_hw_provider(np, of_clk_hw_onecell_get, gemini_clk_data);
+}
+CLK_OF_DECLARE_DRIVER(gemini_cc, "cortina,gemini-syscon", gemini_cc_init);