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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-30 09:22:00 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-30 09:22:00 -0700
commit034dd340b08be1f2f0477ad16131d609f9dbd53c (patch)
tree2536f4b2d7893ccd916b5abdf3c454ad6edc03c2 /drivers/clk/keystone/gate.c
downloadlinux-stable-034dd340b08be1f2f0477ad16131d609f9dbd53c.tar.gz
linux-stable-034dd340b08be1f2f0477ad16131d609f9dbd53c.zip
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
Diffstat (limited to 'drivers/clk/keystone/gate.c')
-rw-r--r--drivers/clk/keystone/gate.c269
1 files changed, 269 insertions, 0 deletions
diff --git a/drivers/clk/keystone/gate.c b/drivers/clk/keystone/gate.c
new file mode 100644
index 000000000..03e854f10
--- /dev/null
+++ b/drivers/clk/keystone/gate.c
@@ -0,0 +1,269 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Clock driver for Keystone 2 based devices
+ *
+ * Copyright (C) 2013 Texas Instruments.
+ * Murali Karicheri <m-karicheri2@ti.com>
+ * Santosh Shilimkar <santosh.shilimkar@ti.com>
+ */
+#include <linux/clk-provider.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+#include <linux/of_address.h>
+#include <linux/of.h>
+#include <linux/module.h>
+
+/* PSC register offsets */
+#define PTCMD 0x120
+#define PTSTAT 0x128
+#define PDSTAT 0x200
+#define PDCTL 0x300
+#define MDSTAT 0x800
+#define MDCTL 0xa00
+
+/* PSC module states */
+#define PSC_STATE_SWRSTDISABLE 0
+#define PSC_STATE_SYNCRST 1
+#define PSC_STATE_DISABLE 2
+#define PSC_STATE_ENABLE 3
+
+#define MDSTAT_STATE_MASK 0x3f
+#define MDSTAT_MCKOUT BIT(12)
+#define PDSTAT_STATE_MASK 0x1f
+#define MDCTL_FORCE BIT(31)
+#define MDCTL_LRESET BIT(8)
+#define PDCTL_NEXT BIT(0)
+
+/* Maximum timeout to bail out state transition for module */
+#define STATE_TRANS_MAX_COUNT 0xffff
+
+static void __iomem *domain_transition_base;
+
+/**
+ * struct clk_psc_data - PSC data
+ * @control_base: Base address for a PSC control
+ * @domain_base: Base address for a PSC domain
+ * @domain_id: PSC domain id number
+ */
+struct clk_psc_data {
+ void __iomem *control_base;
+ void __iomem *domain_base;
+ u32 domain_id;
+};
+
+/**
+ * struct clk_psc - PSC clock structure
+ * @hw: clk_hw for the psc
+ * @psc_data: PSC driver specific data
+ * @lock: Spinlock used by the driver
+ */
+struct clk_psc {
+ struct clk_hw hw;
+ struct clk_psc_data *psc_data;
+ spinlock_t *lock;
+};
+
+static DEFINE_SPINLOCK(psc_lock);
+
+#define to_clk_psc(_hw) container_of(_hw, struct clk_psc, hw)
+
+static void psc_config(void __iomem *control_base, void __iomem *domain_base,
+ u32 next_state, u32 domain_id)
+{
+ u32 ptcmd, pdstat, pdctl, mdstat, mdctl, ptstat;
+ u32 count = STATE_TRANS_MAX_COUNT;
+
+ mdctl = readl(control_base + MDCTL);
+ mdctl &= ~MDSTAT_STATE_MASK;
+ mdctl |= next_state;
+ /* For disable, we always put the module in local reset */
+ if (next_state == PSC_STATE_DISABLE)
+ mdctl &= ~MDCTL_LRESET;
+ writel(mdctl, control_base + MDCTL);
+
+ pdstat = readl(domain_base + PDSTAT);
+ if (!(pdstat & PDSTAT_STATE_MASK)) {
+ pdctl = readl(domain_base + PDCTL);
+ pdctl |= PDCTL_NEXT;
+ writel(pdctl, domain_base + PDCTL);
+ }
+
+ ptcmd = 1 << domain_id;
+ writel(ptcmd, domain_transition_base + PTCMD);
+ do {
+ ptstat = readl(domain_transition_base + PTSTAT);
+ } while (((ptstat >> domain_id) & 1) && count--);
+
+ count = STATE_TRANS_MAX_COUNT;
+ do {
+ mdstat = readl(control_base + MDSTAT);
+ } while (!((mdstat & MDSTAT_STATE_MASK) == next_state) && count--);
+}
+
+static int keystone_clk_is_enabled(struct clk_hw *hw)
+{
+ struct clk_psc *psc = to_clk_psc(hw);
+ struct clk_psc_data *data = psc->psc_data;
+ u32 mdstat = readl(data->control_base + MDSTAT);
+
+ return (mdstat & MDSTAT_MCKOUT) ? 1 : 0;
+}
+
+static int keystone_clk_enable(struct clk_hw *hw)
+{
+ struct clk_psc *psc = to_clk_psc(hw);
+ struct clk_psc_data *data = psc->psc_data;
+ unsigned long flags = 0;
+
+ if (psc->lock)
+ spin_lock_irqsave(psc->lock, flags);
+
+ psc_config(data->control_base, data->domain_base,
+ PSC_STATE_ENABLE, data->domain_id);
+
+ if (psc->lock)
+ spin_unlock_irqrestore(psc->lock, flags);
+
+ return 0;
+}
+
+static void keystone_clk_disable(struct clk_hw *hw)
+{
+ struct clk_psc *psc = to_clk_psc(hw);
+ struct clk_psc_data *data = psc->psc_data;
+ unsigned long flags = 0;
+
+ if (psc->lock)
+ spin_lock_irqsave(psc->lock, flags);
+
+ psc_config(data->control_base, data->domain_base,
+ PSC_STATE_DISABLE, data->domain_id);
+
+ if (psc->lock)
+ spin_unlock_irqrestore(psc->lock, flags);
+}
+
+static const struct clk_ops clk_psc_ops = {
+ .enable = keystone_clk_enable,
+ .disable = keystone_clk_disable,
+ .is_enabled = keystone_clk_is_enabled,
+};
+
+/**
+ * clk_register_psc - register psc clock
+ * @dev: device that is registering this clock
+ * @name: name of this clock
+ * @parent_name: name of clock's parent
+ * @psc_data: platform data to configure this clock
+ * @lock: spinlock used by this clock
+ */
+static struct clk *clk_register_psc(struct device *dev,
+ const char *name,
+ const char *parent_name,
+ struct clk_psc_data *psc_data,
+ spinlock_t *lock)
+{
+ struct clk_init_data init;
+ struct clk_psc *psc;
+ struct clk *clk;
+
+ psc = kzalloc_obj(*psc);
+ if (!psc)
+ return ERR_PTR(-ENOMEM);
+
+ init.name = name;
+ init.ops = &clk_psc_ops;
+ init.flags = 0;
+ init.parent_names = (parent_name ? &parent_name : NULL);
+ init.num_parents = (parent_name ? 1 : 0);
+
+ psc->psc_data = psc_data;
+ psc->lock = lock;
+ psc->hw.init = &init;
+
+ clk = clk_register(NULL, &psc->hw);
+ if (IS_ERR(clk))
+ kfree(psc);
+
+ return clk;
+}
+
+/**
+ * of_psc_clk_init - initialize psc clock through DT
+ * @node: device tree node for this clock
+ * @lock: spinlock used by this clock
+ */
+static void __init of_psc_clk_init(struct device_node *node, spinlock_t *lock)
+{
+ const char *clk_name = node->name;
+ const char *parent_name;
+ struct clk_psc_data *data;
+ struct clk *clk;
+ int i;
+
+ data = kzalloc_obj(*data);
+ if (!data) {
+ pr_err("%s: Out of memory\n", __func__);
+ return;
+ }
+
+ i = of_property_match_string(node, "reg-names", "control");
+ data->control_base = of_iomap(node, i);
+ if (!data->control_base) {
+ pr_err("%s: control ioremap failed\n", __func__);
+ goto out;
+ }
+
+ i = of_property_match_string(node, "reg-names", "domain");
+ data->domain_base = of_iomap(node, i);
+ if (!data->domain_base) {
+ pr_err("%s: domain ioremap failed\n", __func__);
+ goto unmap_ctrl;
+ }
+
+ of_property_read_u32(node, "domain-id", &data->domain_id);
+
+ /* Domain transition registers at fixed address space of domain_id 0 */
+ if (!domain_transition_base && !data->domain_id)
+ domain_transition_base = data->domain_base;
+
+ of_property_read_string(node, "clock-output-names", &clk_name);
+ parent_name = of_clk_get_parent_name(node, 0);
+ if (!parent_name) {
+ pr_err("%s: Parent clock not found\n", __func__);
+ goto unmap_domain;
+ }
+
+ clk = clk_register_psc(NULL, clk_name, parent_name, data, lock);
+ if (!IS_ERR(clk)) {
+ of_clk_add_provider(node, of_clk_src_simple_get, clk);
+ return;
+ }
+
+ pr_err("%s: error registering clk %pOFn\n", __func__, node);
+
+unmap_domain:
+ iounmap(data->domain_base);
+unmap_ctrl:
+ iounmap(data->control_base);
+out:
+ kfree(data);
+ return;
+}
+
+/**
+ * of_keystone_psc_clk_init - initialize psc clock through DT
+ * @node: device tree node for this clock
+ */
+static void __init of_keystone_psc_clk_init(struct device_node *node)
+{
+ of_psc_clk_init(node, &psc_lock);
+}
+CLK_OF_DECLARE(keystone_gate_clk, "ti,keystone,psc-clock",
+ of_keystone_psc_clk_init);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Clock driver for Keystone 2 based devices");
+MODULE_AUTHOR("Murali Karicheri <m-karicheri2@ti.com>");
+MODULE_AUTHOR("Santosh Shilimkar <santosh.shilimkar@ti.com>");