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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
commit4352b8aee98005853aa63f57d6377282de17a33f (patch)
tree27614d7a9ef05c32d089004e104364ce42324837 /drivers/clocksource/timer-fsl-ftm.c
downloadlinux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz
linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip
Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted
Pull I3C updates from Alexandre Belloni: "A new driver this cycle, for the AMD AXI I3C controller. There are also new features such as IBI wakeup support, SETAASA device discovery and ACPI support for the the DAA methods, meaning we can now communicate with the SPD devices on DDR5 modules. New driver: - AMD AXI I3C master controller Subsystem: - I3C Common Command Code (CCC) handling improvements, especially around GET CCCs - SETAASA device discovery support - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as well as I2C devices on I3C bus - IBI-based wakeup support Drivers: - dw: SETAASA support - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C controller support, PIO queue management support for HCI v1.2 - renesas: improve suspend to RAM support, add runtime PM support" * tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits) i3c: dw: reduce do_daa time if there's no client i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2 i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode i3c: dw: rename "pclk" to "apb" to match dt-binding i3c: dw: make struct dw_i3c_cmd smaller i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding i3c: renesas: Don't register devices when ENTDAA times out i3c: master: dw-i3c-master: fix OD timing for first broadcast i3c: mipi-i3c-hci: Advertise IBI wakeup capability i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev() i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI i3c: master: Reject IBI requests from non-IBI-capable devices i3c: master: Add helper to query bus wakeup requirements i3c: master: Report wakeup events for IBIs i3c: master: Support IBI-based wakeup capability i3c: master: Fix potential UAF in i3c_device_match() i3c: master: Fix potential UAF in i3c_device_uevent() i3c: Make dev->desc locking assumptions explicit i3c: master: Fix use-after-free of master->this ...
Diffstat (limited to 'drivers/clocksource/timer-fsl-ftm.c')
-rw-r--r--drivers/clocksource/timer-fsl-ftm.c355
1 files changed, 355 insertions, 0 deletions
diff --git a/drivers/clocksource/timer-fsl-ftm.c b/drivers/clocksource/timer-fsl-ftm.c
new file mode 100644
index 000000000..4eed6cb46
--- /dev/null
+++ b/drivers/clocksource/timer-fsl-ftm.c
@@ -0,0 +1,355 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Freescale FlexTimer Module (FTM) timer driver.
+ *
+ * Copyright 2014 Freescale Semiconductor, Inc.
+ */
+
+#include <linux/clk.h>
+#include <linux/clockchips.h>
+#include <linux/clocksource.h>
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/sched_clock.h>
+#include <linux/slab.h>
+#include <linux/fsl/ftm.h>
+
+#define FTM_SC_CLK(c) ((c) << FTM_SC_CLK_MASK_SHIFT)
+
+struct ftm_clock_device {
+ void __iomem *clksrc_base;
+ void __iomem *clkevt_base;
+ unsigned long periodic_cyc;
+ unsigned long ps;
+ bool big_endian;
+};
+
+static struct ftm_clock_device *priv;
+
+static inline u32 ftm_readl(void __iomem *addr)
+{
+ if (priv->big_endian)
+ return ioread32be(addr);
+ else
+ return ioread32(addr);
+}
+
+static inline void ftm_writel(u32 val, void __iomem *addr)
+{
+ if (priv->big_endian)
+ iowrite32be(val, addr);
+ else
+ iowrite32(val, addr);
+}
+
+static inline void ftm_counter_enable(void __iomem *base)
+{
+ u32 val;
+
+ /* select and enable counter clock source */
+ val = ftm_readl(base + FTM_SC);
+ val &= ~(FTM_SC_PS_MASK | FTM_SC_CLK_MASK);
+ val |= priv->ps | FTM_SC_CLK(1);
+ ftm_writel(val, base + FTM_SC);
+}
+
+static inline void ftm_counter_disable(void __iomem *base)
+{
+ u32 val;
+
+ /* disable counter clock source */
+ val = ftm_readl(base + FTM_SC);
+ val &= ~(FTM_SC_PS_MASK | FTM_SC_CLK_MASK);
+ ftm_writel(val, base + FTM_SC);
+}
+
+static inline void ftm_irq_acknowledge(void __iomem *base)
+{
+ u32 val;
+
+ val = ftm_readl(base + FTM_SC);
+ val &= ~FTM_SC_TOF;
+ ftm_writel(val, base + FTM_SC);
+}
+
+static inline void ftm_irq_enable(void __iomem *base)
+{
+ u32 val;
+
+ val = ftm_readl(base + FTM_SC);
+ val |= FTM_SC_TOIE;
+ ftm_writel(val, base + FTM_SC);
+}
+
+static inline void ftm_irq_disable(void __iomem *base)
+{
+ u32 val;
+
+ val = ftm_readl(base + FTM_SC);
+ val &= ~FTM_SC_TOIE;
+ ftm_writel(val, base + FTM_SC);
+}
+
+static inline void ftm_reset_counter(void __iomem *base)
+{
+ /*
+ * The CNT register contains the FTM counter value.
+ * Reset clears the CNT register. Writing any value to COUNT
+ * updates the counter with its initial value, CNTIN.
+ */
+ ftm_writel(0x00, base + FTM_CNT);
+}
+
+static u64 notrace ftm_read_sched_clock(void)
+{
+ return ftm_readl(priv->clksrc_base + FTM_CNT);
+}
+
+static int ftm_set_next_event(unsigned long delta,
+ struct clock_event_device *unused)
+{
+ /*
+ * The CNNIN and MOD are all double buffer registers, writing
+ * to the MOD register latches the value into a buffer. The MOD
+ * register is updated with the value of its write buffer with
+ * the following scenario:
+ * a, the counter source clock is disabled.
+ */
+ ftm_counter_disable(priv->clkevt_base);
+
+ /* Force the value of CNTIN to be loaded into the FTM counter */
+ ftm_reset_counter(priv->clkevt_base);
+
+ /*
+ * The counter increments until the value of MOD is reached,
+ * at which point the counter is reloaded with the value of CNTIN.
+ * The TOF (the overflow flag) bit is set when the FTM counter
+ * changes from MOD to CNTIN. So we should using the delta - 1.
+ */
+ ftm_writel(delta - 1, priv->clkevt_base + FTM_MOD);
+
+ ftm_counter_enable(priv->clkevt_base);
+
+ ftm_irq_enable(priv->clkevt_base);
+
+ return 0;
+}
+
+static int ftm_set_oneshot(struct clock_event_device *evt)
+{
+ ftm_counter_disable(priv->clkevt_base);
+ return 0;
+}
+
+static int ftm_set_periodic(struct clock_event_device *evt)
+{
+ ftm_set_next_event(priv->periodic_cyc, evt);
+ return 0;
+}
+
+static irqreturn_t ftm_evt_interrupt(int irq, void *dev_id)
+{
+ struct clock_event_device *evt = dev_id;
+
+ ftm_irq_acknowledge(priv->clkevt_base);
+
+ if (likely(clockevent_state_oneshot(evt))) {
+ ftm_irq_disable(priv->clkevt_base);
+ ftm_counter_disable(priv->clkevt_base);
+ }
+
+ evt->event_handler(evt);
+
+ return IRQ_HANDLED;
+}
+
+static struct clock_event_device ftm_clockevent = {
+ .name = "Freescale ftm timer",
+ .features = CLOCK_EVT_FEAT_PERIODIC |
+ CLOCK_EVT_FEAT_ONESHOT,
+ .set_state_periodic = ftm_set_periodic,
+ .set_state_oneshot = ftm_set_oneshot,
+ .set_next_event = ftm_set_next_event,
+ .rating = 300,
+};
+
+static int __init ftm_clockevent_init(unsigned long freq, int irq)
+{
+ int err;
+
+ ftm_writel(0x00, priv->clkevt_base + FTM_CNTIN);
+ ftm_writel(~0u, priv->clkevt_base + FTM_MOD);
+
+ ftm_reset_counter(priv->clkevt_base);
+
+ err = request_irq(irq, ftm_evt_interrupt, IRQF_TIMER | IRQF_IRQPOLL,
+ "Freescale ftm timer", &ftm_clockevent);
+ if (err) {
+ pr_err("ftm: setup irq failed: %d\n", err);
+ return err;
+ }
+
+ ftm_clockevent.cpumask = cpumask_of(0);
+ ftm_clockevent.irq = irq;
+
+ clockevents_config_and_register(&ftm_clockevent,
+ freq / (1 << priv->ps),
+ 1, 0xffff);
+
+ ftm_counter_enable(priv->clkevt_base);
+
+ return 0;
+}
+
+static int __init ftm_clocksource_init(unsigned long freq)
+{
+ int err;
+
+ ftm_writel(0x00, priv->clksrc_base + FTM_CNTIN);
+ ftm_writel(~0u, priv->clksrc_base + FTM_MOD);
+
+ ftm_reset_counter(priv->clksrc_base);
+
+ sched_clock_register(ftm_read_sched_clock, 16, freq / (1 << priv->ps));
+ err = clocksource_mmio_init(priv->clksrc_base + FTM_CNT, "fsl-ftm",
+ freq / (1 << priv->ps), 300, 16,
+ clocksource_mmio_readl_up);
+ if (err) {
+ pr_err("ftm: init clock source mmio failed: %d\n", err);
+ return err;
+ }
+
+ ftm_counter_enable(priv->clksrc_base);
+
+ return 0;
+}
+
+static int __init __ftm_clk_init(struct device_node *np, char *cnt_name,
+ char *ftm_name)
+{
+ struct clk *clk;
+ int err;
+
+ clk = of_clk_get_by_name(np, cnt_name);
+ if (IS_ERR(clk)) {
+ pr_err("ftm: Cannot get \"%s\": %ld\n", cnt_name, PTR_ERR(clk));
+ return PTR_ERR(clk);
+ }
+ err = clk_prepare_enable(clk);
+ if (err) {
+ pr_err("ftm: clock failed to prepare+enable \"%s\": %d\n",
+ cnt_name, err);
+ return err;
+ }
+
+ clk = of_clk_get_by_name(np, ftm_name);
+ if (IS_ERR(clk)) {
+ pr_err("ftm: Cannot get \"%s\": %ld\n", ftm_name, PTR_ERR(clk));
+ return PTR_ERR(clk);
+ }
+ err = clk_prepare_enable(clk);
+ if (err)
+ pr_err("ftm: clock failed to prepare+enable \"%s\": %d\n",
+ ftm_name, err);
+
+ return clk_get_rate(clk);
+}
+
+static unsigned long __init ftm_clk_init(struct device_node *np)
+{
+ long freq;
+
+ freq = __ftm_clk_init(np, "ftm-evt-counter-en", "ftm-evt");
+ if (freq <= 0)
+ return 0;
+
+ freq = __ftm_clk_init(np, "ftm-src-counter-en", "ftm-src");
+ if (freq <= 0)
+ return 0;
+
+ return freq;
+}
+
+static int __init ftm_calc_closest_round_cyc(unsigned long freq)
+{
+ priv->ps = 0;
+
+ /* The counter register is only using the lower 16 bits, and
+ * if the 'freq' value is to big here, then the periodic_cyc
+ * may exceed 0xFFFF.
+ */
+ do {
+ priv->periodic_cyc = DIV_ROUND_CLOSEST(freq,
+ HZ * (1 << priv->ps++));
+ } while (priv->periodic_cyc > 0xFFFF);
+
+ if (priv->ps > FTM_PS_MAX) {
+ pr_err("ftm: the prescaler is %lu > %d\n",
+ priv->ps, FTM_PS_MAX);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int __init ftm_timer_init(struct device_node *np)
+{
+ unsigned long freq;
+ int ret, irq;
+
+ priv = kzalloc_obj(*priv);
+ if (!priv)
+ return -ENOMEM;
+
+ ret = -ENXIO;
+ priv->clkevt_base = of_iomap(np, 0);
+ if (!priv->clkevt_base) {
+ pr_err("ftm: unable to map event timer registers\n");
+ goto err_clkevt;
+ }
+
+ priv->clksrc_base = of_iomap(np, 1);
+ if (!priv->clksrc_base) {
+ pr_err("ftm: unable to map source timer registers\n");
+ goto err_clksrc;
+ }
+
+ ret = -EINVAL;
+ irq = irq_of_parse_and_map(np, 0);
+ if (irq <= 0) {
+ pr_err("ftm: unable to get IRQ from DT, %d\n", irq);
+ goto err;
+ }
+
+ priv->big_endian = of_property_read_bool(np, "big-endian");
+
+ freq = ftm_clk_init(np);
+ if (!freq)
+ goto err;
+
+ ret = ftm_calc_closest_round_cyc(freq);
+ if (ret)
+ goto err;
+
+ ret = ftm_clocksource_init(freq);
+ if (ret)
+ goto err;
+
+ ret = ftm_clockevent_init(freq, irq);
+ if (ret)
+ goto err;
+
+ return 0;
+
+err:
+ iounmap(priv->clksrc_base);
+err_clksrc:
+ iounmap(priv->clkevt_base);
+err_clkevt:
+ kfree(priv);
+ return ret;
+}
+TIMER_OF_DECLARE(flextimer, "fsl,ftm-timer", ftm_timer_init);