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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-23 13:28:57 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-23 13:28:57 -0700 |
| commit | 4352b8aee98005853aa63f57d6377282de17a33f (patch) | |
| tree | 27614d7a9ef05c32d089004e104364ce42324837 /drivers/clocksource/timer-keystone.c | |
| download | linux-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-keystone.c')
| -rw-r--r-- | drivers/clocksource/timer-keystone.c | 226 |
1 files changed, 226 insertions, 0 deletions
diff --git a/drivers/clocksource/timer-keystone.c b/drivers/clocksource/timer-keystone.c new file mode 100644 index 000000000..fea8a4f85 --- /dev/null +++ b/drivers/clocksource/timer-keystone.c @@ -0,0 +1,226 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Keystone broadcast clock-event + * + * Copyright 2013 Texas Instruments, Inc. + * + * Author: Ivan Khoronzhuk <ivan.khoronzhuk@ti.com> + */ + +#include <linux/clk.h> +#include <linux/clockchips.h> +#include <linux/clocksource.h> +#include <linux/interrupt.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> + +#define TIMER_NAME "timer-keystone" + +/* Timer register offsets */ +#define TIM12 0x10 +#define TIM34 0x14 +#define PRD12 0x18 +#define PRD34 0x1c +#define TCR 0x20 +#define TGCR 0x24 +#define INTCTLSTAT 0x44 + +/* Timer register bitfields */ +#define TCR_ENAMODE_MASK 0xC0 +#define TCR_ENAMODE_ONESHOT_MASK 0x40 +#define TCR_ENAMODE_PERIODIC_MASK 0x80 + +#define TGCR_TIM_UNRESET_MASK 0x03 +#define INTCTLSTAT_ENINT_MASK 0x01 + +/** + * struct keystone_timer: holds timer's data + * @base: timer memory base address + * @hz_period: cycles per HZ period + * @event_dev: event device based on timer + */ +static struct keystone_timer { + void __iomem *base; + unsigned long hz_period; + struct clock_event_device event_dev; +} timer; + +static inline u32 keystone_timer_readl(unsigned long rg) +{ + return readl_relaxed(timer.base + rg); +} + +static inline void keystone_timer_writel(u32 val, unsigned long rg) +{ + writel_relaxed(val, timer.base + rg); +} + +/** + * keystone_timer_barrier: write memory barrier + * use explicit barrier to avoid using readl/writel non relaxed function + * variants, because in our case non relaxed variants hide the true places + * where barrier is needed. + */ +static inline void keystone_timer_barrier(void) +{ + __iowmb(); +} + +/** + * keystone_timer_config: configures timer to work in oneshot/periodic modes. + * @ mask: mask of the mode to configure + * @ period: cycles number to configure for + */ +static int keystone_timer_config(u64 period, int mask) +{ + u32 tcr; + u32 off; + + tcr = keystone_timer_readl(TCR); + off = tcr & ~(TCR_ENAMODE_MASK); + + /* set enable mode */ + tcr |= mask; + + /* disable timer */ + keystone_timer_writel(off, TCR); + /* here we have to be sure the timer has been disabled */ + keystone_timer_barrier(); + + /* reset counter to zero, set new period */ + keystone_timer_writel(0, TIM12); + keystone_timer_writel(0, TIM34); + keystone_timer_writel(period & 0xffffffff, PRD12); + keystone_timer_writel(period >> 32, PRD34); + + /* + * enable timer + * here we have to be sure that CNTLO, CNTHI, PRDLO, PRDHI registers + * have been written. + */ + keystone_timer_barrier(); + keystone_timer_writel(tcr, TCR); + return 0; +} + +static void keystone_timer_disable(void) +{ + u32 tcr; + + tcr = keystone_timer_readl(TCR); + + /* disable timer */ + tcr &= ~(TCR_ENAMODE_MASK); + keystone_timer_writel(tcr, TCR); +} + +static irqreturn_t keystone_timer_interrupt(int irq, void *dev_id) +{ + struct clock_event_device *evt = dev_id; + + evt->event_handler(evt); + return IRQ_HANDLED; +} + +static int keystone_set_next_event(unsigned long cycles, + struct clock_event_device *evt) +{ + return keystone_timer_config(cycles, TCR_ENAMODE_ONESHOT_MASK); +} + +static int keystone_shutdown(struct clock_event_device *evt) +{ + keystone_timer_disable(); + return 0; +} + +static int keystone_set_periodic(struct clock_event_device *evt) +{ + keystone_timer_config(timer.hz_period, TCR_ENAMODE_PERIODIC_MASK); + return 0; +} + +static int __init keystone_timer_init(struct device_node *np) +{ + struct clock_event_device *event_dev = &timer.event_dev; + unsigned long rate; + struct clk *clk; + int irq, error; + + irq = irq_of_parse_and_map(np, 0); + if (!irq) { + pr_err("%s: failed to map interrupts\n", __func__); + return -EINVAL; + } + + timer.base = of_iomap(np, 0); + if (!timer.base) { + pr_err("%s: failed to map registers\n", __func__); + return -ENXIO; + } + + clk = of_clk_get(np, 0); + if (IS_ERR(clk)) { + pr_err("%s: failed to get clock\n", __func__); + iounmap(timer.base); + return PTR_ERR(clk); + } + + error = clk_prepare_enable(clk); + if (error) { + pr_err("%s: failed to enable clock\n", __func__); + goto err; + } + + rate = clk_get_rate(clk); + + /* disable, use internal clock source */ + keystone_timer_writel(0, TCR); + /* here we have to be sure the timer has been disabled */ + keystone_timer_barrier(); + + /* reset timer as 64-bit, no pre-scaler, plus features are disabled */ + keystone_timer_writel(0, TGCR); + + /* unreset timer */ + keystone_timer_writel(TGCR_TIM_UNRESET_MASK, TGCR); + + /* init counter to zero */ + keystone_timer_writel(0, TIM12); + keystone_timer_writel(0, TIM34); + + timer.hz_period = DIV_ROUND_UP(rate, HZ); + + /* enable timer interrupts */ + keystone_timer_writel(INTCTLSTAT_ENINT_MASK, INTCTLSTAT); + + error = request_irq(irq, keystone_timer_interrupt, IRQF_TIMER, + TIMER_NAME, event_dev); + if (error) { + pr_err("%s: failed to setup irq\n", __func__); + goto err; + } + + /* setup clockevent */ + event_dev->features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT; + event_dev->set_next_event = keystone_set_next_event; + event_dev->set_state_shutdown = keystone_shutdown; + event_dev->set_state_periodic = keystone_set_periodic; + event_dev->set_state_oneshot = keystone_shutdown; + event_dev->cpumask = cpu_possible_mask; + event_dev->owner = THIS_MODULE; + event_dev->name = TIMER_NAME; + event_dev->irq = irq; + + clockevents_config_and_register(event_dev, rate, 1, ULONG_MAX); + + pr_info("keystone timer clock @%lu Hz\n", rate); + return 0; +err: + clk_put(clk); + iounmap(timer.base); + return error; +} + +TIMER_OF_DECLARE(keystone_timer, "ti,keystone-timer", + keystone_timer_init); |
