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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-lpc32xx.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-lpc32xx.c')
-rw-r--r--drivers/clocksource/timer-lpc32xx.c310
1 files changed, 310 insertions, 0 deletions
diff --git a/drivers/clocksource/timer-lpc32xx.c b/drivers/clocksource/timer-lpc32xx.c
new file mode 100644
index 000000000..68eae6378
--- /dev/null
+++ b/drivers/clocksource/timer-lpc32xx.c
@@ -0,0 +1,310 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Clocksource driver for NXP LPC32xx/18xx/43xx timer
+ *
+ * Copyright (C) 2015 Joachim Eastwood <manabian@gmail.com>
+ *
+ * Based on:
+ * time-efm32 Copyright (C) 2013 Pengutronix
+ * mach-lpc32xx/timer.c Copyright (C) 2009 - 2010 NXP Semiconductors
+ */
+
+#define pr_fmt(fmt) "%s: " fmt, __func__
+
+#include <linux/clk.h>
+#include <linux/clockchips.h>
+#include <linux/clocksource.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/kernel.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/sched_clock.h>
+
+#define LPC32XX_TIMER_IR 0x000
+#define LPC32XX_TIMER_IR_MR0INT BIT(0)
+#define LPC32XX_TIMER_TCR 0x004
+#define LPC32XX_TIMER_TCR_CEN BIT(0)
+#define LPC32XX_TIMER_TCR_CRST BIT(1)
+#define LPC32XX_TIMER_TC 0x008
+#define LPC32XX_TIMER_PR 0x00c
+#define LPC32XX_TIMER_MCR 0x014
+#define LPC32XX_TIMER_MCR_MR0I BIT(0)
+#define LPC32XX_TIMER_MCR_MR0R BIT(1)
+#define LPC32XX_TIMER_MCR_MR0S BIT(2)
+#define LPC32XX_TIMER_MR0 0x018
+#define LPC32XX_TIMER_CTCR 0x070
+
+struct lpc32xx_clock_event_ddata {
+ struct clock_event_device evtdev;
+ void __iomem *base;
+ u32 ticks_per_jiffy;
+};
+
+/* Needed for the sched clock */
+static void __iomem *clocksource_timer_counter;
+
+static u64 notrace lpc32xx_read_sched_clock(void)
+{
+ return readl(clocksource_timer_counter);
+}
+
+static unsigned long lpc32xx_delay_timer_read(void)
+{
+ return readl(clocksource_timer_counter);
+}
+
+static struct delay_timer lpc32xx_delay_timer = {
+ .read_current_timer = lpc32xx_delay_timer_read,
+};
+
+static int lpc32xx_clkevt_next_event(unsigned long delta,
+ struct clock_event_device *evtdev)
+{
+ struct lpc32xx_clock_event_ddata *ddata =
+ container_of(evtdev, struct lpc32xx_clock_event_ddata, evtdev);
+
+ /*
+ * Place timer in reset and program the delta in the match
+ * channel 0 (MR0). When the timer counter matches the value
+ * in MR0 register the match will trigger an interrupt.
+ * After setup the timer is released from reset and enabled.
+ */
+ writel_relaxed(LPC32XX_TIMER_TCR_CRST, ddata->base + LPC32XX_TIMER_TCR);
+ writel_relaxed(delta, ddata->base + LPC32XX_TIMER_MR0);
+ writel_relaxed(LPC32XX_TIMER_TCR_CEN, ddata->base + LPC32XX_TIMER_TCR);
+
+ return 0;
+}
+
+static int lpc32xx_clkevt_shutdown(struct clock_event_device *evtdev)
+{
+ struct lpc32xx_clock_event_ddata *ddata =
+ container_of(evtdev, struct lpc32xx_clock_event_ddata, evtdev);
+
+ /* Disable the timer */
+ writel_relaxed(0, ddata->base + LPC32XX_TIMER_TCR);
+
+ return 0;
+}
+
+static int lpc32xx_clkevt_oneshot(struct clock_event_device *evtdev)
+{
+ struct lpc32xx_clock_event_ddata *ddata =
+ container_of(evtdev, struct lpc32xx_clock_event_ddata, evtdev);
+
+ /*
+ * When using oneshot, we must also disable the timer
+ * to wait for the first call to set_next_event().
+ */
+ writel_relaxed(0, ddata->base + LPC32XX_TIMER_TCR);
+
+ /* Enable interrupt, reset on match and stop on match (MCR). */
+ writel_relaxed(LPC32XX_TIMER_MCR_MR0I | LPC32XX_TIMER_MCR_MR0R |
+ LPC32XX_TIMER_MCR_MR0S, ddata->base + LPC32XX_TIMER_MCR);
+ return 0;
+}
+
+static int lpc32xx_clkevt_periodic(struct clock_event_device *evtdev)
+{
+ struct lpc32xx_clock_event_ddata *ddata =
+ container_of(evtdev, struct lpc32xx_clock_event_ddata, evtdev);
+
+ /* Enable interrupt and reset on match. */
+ writel_relaxed(LPC32XX_TIMER_MCR_MR0I | LPC32XX_TIMER_MCR_MR0R,
+ ddata->base + LPC32XX_TIMER_MCR);
+
+ /*
+ * Place timer in reset and program the delta in the match
+ * channel 0 (MR0).
+ */
+ writel_relaxed(LPC32XX_TIMER_TCR_CRST, ddata->base + LPC32XX_TIMER_TCR);
+ writel_relaxed(ddata->ticks_per_jiffy, ddata->base + LPC32XX_TIMER_MR0);
+ writel_relaxed(LPC32XX_TIMER_TCR_CEN, ddata->base + LPC32XX_TIMER_TCR);
+
+ return 0;
+}
+
+static irqreturn_t lpc32xx_clock_event_handler(int irq, void *dev_id)
+{
+ struct lpc32xx_clock_event_ddata *ddata = dev_id;
+
+ /* Clear match on channel 0 */
+ writel_relaxed(LPC32XX_TIMER_IR_MR0INT, ddata->base + LPC32XX_TIMER_IR);
+
+ ddata->evtdev.event_handler(&ddata->evtdev);
+
+ return IRQ_HANDLED;
+}
+
+static struct lpc32xx_clock_event_ddata lpc32xx_clk_event_ddata = {
+ .evtdev = {
+ .name = "lpc3220 clockevent",
+ .features = CLOCK_EVT_FEAT_ONESHOT |
+ CLOCK_EVT_FEAT_PERIODIC,
+ .rating = 300,
+ .set_next_event = lpc32xx_clkevt_next_event,
+ .set_state_shutdown = lpc32xx_clkevt_shutdown,
+ .set_state_oneshot = lpc32xx_clkevt_oneshot,
+ .set_state_periodic = lpc32xx_clkevt_periodic,
+ },
+};
+
+static int __init lpc32xx_clocksource_init(struct device_node *np)
+{
+ void __iomem *base;
+ unsigned long rate;
+ struct clk *clk;
+ int ret;
+
+ clk = of_clk_get_by_name(np, "timerclk");
+ if (IS_ERR(clk)) {
+ pr_err("clock get failed (%ld)\n", PTR_ERR(clk));
+ return PTR_ERR(clk);
+ }
+
+ ret = clk_prepare_enable(clk);
+ if (ret) {
+ pr_err("clock enable failed (%d)\n", ret);
+ goto err_clk_enable;
+ }
+
+ base = of_iomap(np, 0);
+ if (!base) {
+ pr_err("unable to map registers\n");
+ ret = -EADDRNOTAVAIL;
+ goto err_iomap;
+ }
+
+ /*
+ * Disable and reset timer then set it to free running timer
+ * mode (CTCR) with no prescaler (PR) or match operations (MCR).
+ * After setup the timer is released from reset and enabled.
+ */
+ writel_relaxed(LPC32XX_TIMER_TCR_CRST, base + LPC32XX_TIMER_TCR);
+ writel_relaxed(0, base + LPC32XX_TIMER_PR);
+ writel_relaxed(0, base + LPC32XX_TIMER_MCR);
+ writel_relaxed(0, base + LPC32XX_TIMER_CTCR);
+ writel_relaxed(LPC32XX_TIMER_TCR_CEN, base + LPC32XX_TIMER_TCR);
+
+ rate = clk_get_rate(clk);
+ ret = clocksource_mmio_init(base + LPC32XX_TIMER_TC, "lpc3220 timer",
+ rate, 300, 32, clocksource_mmio_readl_up);
+ if (ret) {
+ pr_err("failed to init clocksource (%d)\n", ret);
+ goto err_clocksource_init;
+ }
+
+ clocksource_timer_counter = base + LPC32XX_TIMER_TC;
+ lpc32xx_delay_timer.freq = rate;
+ register_current_timer_delay(&lpc32xx_delay_timer);
+ sched_clock_register(lpc32xx_read_sched_clock, 32, rate);
+
+ return 0;
+
+err_clocksource_init:
+ iounmap(base);
+err_iomap:
+ clk_disable_unprepare(clk);
+err_clk_enable:
+ clk_put(clk);
+ return ret;
+}
+
+static int __init lpc32xx_clockevent_init(struct device_node *np)
+{
+ void __iomem *base;
+ unsigned long rate;
+ struct clk *clk;
+ int ret, irq;
+
+ clk = of_clk_get_by_name(np, "timerclk");
+ if (IS_ERR(clk)) {
+ pr_err("clock get failed (%ld)\n", PTR_ERR(clk));
+ return PTR_ERR(clk);
+ }
+
+ ret = clk_prepare_enable(clk);
+ if (ret) {
+ pr_err("clock enable failed (%d)\n", ret);
+ goto err_clk_enable;
+ }
+
+ base = of_iomap(np, 0);
+ if (!base) {
+ pr_err("unable to map registers\n");
+ ret = -EADDRNOTAVAIL;
+ goto err_iomap;
+ }
+
+ irq = irq_of_parse_and_map(np, 0);
+ if (!irq) {
+ pr_err("get irq failed\n");
+ ret = -ENOENT;
+ goto err_irq;
+ }
+
+ /*
+ * Disable timer and clear any pending interrupt (IR) on match
+ * channel 0 (MR0). Clear the prescaler as it's not used.
+ */
+ writel_relaxed(0, base + LPC32XX_TIMER_TCR);
+ writel_relaxed(0, base + LPC32XX_TIMER_PR);
+ writel_relaxed(0, base + LPC32XX_TIMER_CTCR);
+ writel_relaxed(LPC32XX_TIMER_IR_MR0INT, base + LPC32XX_TIMER_IR);
+
+ rate = clk_get_rate(clk);
+ lpc32xx_clk_event_ddata.base = base;
+ lpc32xx_clk_event_ddata.ticks_per_jiffy = DIV_ROUND_CLOSEST(rate, HZ);
+ clockevents_config_and_register(&lpc32xx_clk_event_ddata.evtdev,
+ rate, 1, -1);
+
+ ret = request_irq(irq, lpc32xx_clock_event_handler,
+ IRQF_TIMER | IRQF_IRQPOLL, "lpc3220 clockevent",
+ &lpc32xx_clk_event_ddata);
+ if (ret) {
+ pr_err("request irq failed\n");
+ goto err_irq;
+ }
+
+ return 0;
+
+err_irq:
+ iounmap(base);
+err_iomap:
+ clk_disable_unprepare(clk);
+err_clk_enable:
+ clk_put(clk);
+ return ret;
+}
+
+/*
+ * This function asserts that we have exactly one clocksource and one
+ * clock_event_device in the end.
+ */
+static int __init lpc32xx_timer_init(struct device_node *np)
+{
+ static int has_clocksource, has_clockevent;
+ int ret = 0;
+
+ if (!has_clocksource) {
+ ret = lpc32xx_clocksource_init(np);
+ if (!ret) {
+ has_clocksource = 1;
+ return 0;
+ }
+ }
+
+ if (!has_clockevent) {
+ ret = lpc32xx_clockevent_init(np);
+ if (!ret) {
+ has_clockevent = 1;
+ return 0;
+ }
+ }
+
+ return ret;
+}
+TIMER_OF_DECLARE(lpc32xx_timer, "nxp,lpc3220-timer", lpc32xx_timer_init);