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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-imx-tpm.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-imx-tpm.c')
-rw-r--r--drivers/clocksource/timer-imx-tpm.c244
1 files changed, 244 insertions, 0 deletions
diff --git a/drivers/clocksource/timer-imx-tpm.c b/drivers/clocksource/timer-imx-tpm.c
new file mode 100644
index 000000000..92c025b70
--- /dev/null
+++ b/drivers/clocksource/timer-imx-tpm.c
@@ -0,0 +1,244 @@
+// SPDX-License-Identifier: GPL-2.0+
+//
+// Copyright 2016 Freescale Semiconductor, Inc.
+// Copyright 2017 NXP
+
+#include <linux/clk.h>
+#include <linux/clockchips.h>
+#include <linux/clocksource.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/sched_clock.h>
+
+#include "timer-of.h"
+
+#define TPM_PARAM 0x4
+#define TPM_PARAM_WIDTH_SHIFT 16
+#define TPM_PARAM_WIDTH_MASK (0xff << 16)
+#define TPM_SC 0x10
+#define TPM_SC_CMOD_INC_PER_CNT (0x1 << 3)
+#define TPM_SC_CMOD_DIV_DEFAULT 0x3
+#define TPM_SC_CMOD_DIV_MAX 0x7
+#define TPM_SC_TOF_MASK (0x1 << 7)
+#define TPM_CNT 0x14
+#define TPM_MOD 0x18
+#define TPM_STATUS 0x1c
+#define TPM_STATUS_CH0F BIT(0)
+#define TPM_C0SC 0x20
+#define TPM_C0SC_CHIE BIT(6)
+#define TPM_C0SC_MODE_SHIFT 2
+#define TPM_C0SC_MODE_MASK 0x3c
+#define TPM_C0SC_MODE_SW_COMPARE 0x4
+#define TPM_C0SC_CHF_MASK (0x1 << 7)
+#define TPM_C0V 0x24
+
+static int counter_width __ro_after_init;
+static void __iomem *timer_base __ro_after_init;
+
+static inline void tpm_timer_disable(void)
+{
+ unsigned int val;
+
+ /* channel disable */
+ val = readl(timer_base + TPM_C0SC);
+ val &= ~(TPM_C0SC_MODE_MASK | TPM_C0SC_CHIE);
+ writel(val, timer_base + TPM_C0SC);
+}
+
+static inline void tpm_timer_enable(void)
+{
+ unsigned int val;
+
+ /* channel enabled in sw compare mode */
+ val = readl(timer_base + TPM_C0SC);
+ val |= (TPM_C0SC_MODE_SW_COMPARE << TPM_C0SC_MODE_SHIFT) |
+ TPM_C0SC_CHIE;
+ writel(val, timer_base + TPM_C0SC);
+}
+
+static inline void tpm_irq_acknowledge(void)
+{
+ writel(TPM_STATUS_CH0F, timer_base + TPM_STATUS);
+}
+
+static inline unsigned long tpm_read_counter(void)
+{
+ return readl(timer_base + TPM_CNT);
+}
+
+#if defined(CONFIG_ARM)
+static struct delay_timer tpm_delay_timer;
+
+static unsigned long tpm_read_current_timer(void)
+{
+ return tpm_read_counter();
+}
+
+static u64 notrace tpm_read_sched_clock(void)
+{
+ return tpm_read_counter();
+}
+#endif
+
+static int tpm_set_next_event(unsigned long delta,
+ struct clock_event_device *evt)
+{
+ unsigned long next, prev, now;
+
+ prev = tpm_read_counter();
+ next = prev + delta;
+ writel(next, timer_base + TPM_C0V);
+ now = tpm_read_counter();
+
+ /*
+ * Need to wait CNT increase at least 1 cycle to make sure
+ * the C0V has been updated into HW.
+ */
+ if ((next & 0xffffffff) != readl(timer_base + TPM_C0V))
+ while (now == tpm_read_counter())
+ ;
+
+ /*
+ * NOTE: We observed in a very small probability, the bus fabric
+ * contention between GPU and A7 may results a few cycles delay
+ * of writing CNT registers which may cause the min_delta event got
+ * missed, so we need add a ETIME check here in case it happened.
+ */
+ return (now - prev) >= delta ? -ETIME : 0;
+}
+
+static int tpm_set_state_oneshot(struct clock_event_device *evt)
+{
+ tpm_timer_enable();
+
+ return 0;
+}
+
+static int tpm_set_state_shutdown(struct clock_event_device *evt)
+{
+ tpm_timer_disable();
+
+ return 0;
+}
+
+static irqreturn_t tpm_timer_interrupt(int irq, void *dev_id)
+{
+ struct clock_event_device *evt = dev_id;
+
+ tpm_irq_acknowledge();
+
+ evt->event_handler(evt);
+
+ return IRQ_HANDLED;
+}
+
+static struct timer_of to_tpm = {
+ .flags = TIMER_OF_IRQ | TIMER_OF_BASE | TIMER_OF_CLOCK,
+ .clkevt = {
+ .name = "i.MX TPM Timer",
+ .rating = 200,
+ .features = CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_DYNIRQ,
+ .set_state_shutdown = tpm_set_state_shutdown,
+ .set_state_oneshot = tpm_set_state_oneshot,
+ .set_next_event = tpm_set_next_event,
+ .cpumask = cpu_possible_mask,
+ },
+ .of_irq = {
+ .handler = tpm_timer_interrupt,
+ .flags = IRQF_TIMER,
+ },
+ .of_clk = {
+ .name = "per",
+ },
+};
+
+static int __init tpm_clocksource_init(void)
+{
+#if defined(CONFIG_ARM)
+ tpm_delay_timer.read_current_timer = &tpm_read_current_timer;
+ tpm_delay_timer.freq = timer_of_rate(&to_tpm) >> 3;
+ register_current_timer_delay(&tpm_delay_timer);
+
+ sched_clock_register(tpm_read_sched_clock, counter_width,
+ timer_of_rate(&to_tpm) >> 3);
+#endif
+
+ return clocksource_mmio_init(timer_base + TPM_CNT,
+ "imx-tpm",
+ timer_of_rate(&to_tpm) >> 3,
+ to_tpm.clkevt.rating,
+ counter_width,
+ clocksource_mmio_readl_up);
+}
+
+static void __init tpm_clockevent_init(void)
+{
+ clockevents_config_and_register(&to_tpm.clkevt,
+ timer_of_rate(&to_tpm) >> 3,
+ 300,
+ GENMASK(counter_width - 1,
+ 1));
+}
+
+static int __init tpm_timer_init(struct device_node *np)
+{
+ struct clk *ipg;
+ int ret;
+
+ ipg = of_clk_get_by_name(np, "ipg");
+ if (IS_ERR(ipg)) {
+ pr_err("tpm: failed to get ipg clk\n");
+ return -ENODEV;
+ }
+ /* enable clk before accessing registers */
+ ret = clk_prepare_enable(ipg);
+ if (ret) {
+ pr_err("tpm: ipg clock enable failed (%d)\n", ret);
+ clk_put(ipg);
+ return ret;
+ }
+
+ ret = timer_of_init(np, &to_tpm);
+ if (ret)
+ return ret;
+
+ timer_base = timer_of_base(&to_tpm);
+
+ counter_width = (readl(timer_base + TPM_PARAM)
+ & TPM_PARAM_WIDTH_MASK) >> TPM_PARAM_WIDTH_SHIFT;
+ /* use rating 200 for 32-bit counter and 150 for 16-bit counter */
+ to_tpm.clkevt.rating = counter_width == 0x20 ? 200 : 150;
+
+ /*
+ * Initialize tpm module to a known state
+ * 1) Counter disabled
+ * 2) TPM counter operates in up counting mode
+ * 3) Timer Overflow Interrupt disabled
+ * 4) Channel0 disabled
+ * 5) DMA transfers disabled
+ */
+ /* make sure counter is disabled */
+ writel(0, timer_base + TPM_SC);
+ /* TOF is W1C */
+ writel(TPM_SC_TOF_MASK, timer_base + TPM_SC);
+ writel(0, timer_base + TPM_CNT);
+ /* CHF is W1C */
+ writel(TPM_C0SC_CHF_MASK, timer_base + TPM_C0SC);
+
+ /*
+ * increase per cnt,
+ * div 8 for 32-bit counter and div 128 for 16-bit counter
+ */
+ writel(TPM_SC_CMOD_INC_PER_CNT |
+ (counter_width == 0x20 ?
+ TPM_SC_CMOD_DIV_DEFAULT : TPM_SC_CMOD_DIV_MAX),
+ timer_base + TPM_SC);
+
+ /* set MOD register to maximum for free running mode */
+ writel(GENMASK(counter_width - 1, 0), timer_base + TPM_MOD);
+
+ tpm_clockevent_init();
+
+ return tpm_clocksource_init();
+}
+TIMER_OF_DECLARE(imx7ulp, "fsl,imx7ulp-tpm", tpm_timer_init);