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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/asm9260_timer.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/asm9260_timer.c')
| -rw-r--r-- | drivers/clocksource/asm9260_timer.c | 243 |
1 files changed, 243 insertions, 0 deletions
diff --git a/drivers/clocksource/asm9260_timer.c b/drivers/clocksource/asm9260_timer.c new file mode 100644 index 000000000..8f97ab0b0 --- /dev/null +++ b/drivers/clocksource/asm9260_timer.c @@ -0,0 +1,243 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (C) 2014 Oleksij Rempel <linux@rempel-privat.de> + */ + +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/sched.h> +#include <linux/clk.h> +#include <linux/clocksource.h> +#include <linux/clockchips.h> +#include <linux/io.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <linux/bitops.h> + +#define DRIVER_NAME "asm9260-timer" + +/* + * this device provide 4 offsets for each register: + * 0x0 - plain read write mode + * 0x4 - set mode, OR logic. + * 0x8 - clr mode, XOR logic. + * 0xc - togle mode. + */ +#define SET_REG 4 +#define CLR_REG 8 + +#define HW_IR 0x0000 /* RW. Interrupt */ +#define BM_IR_CR0 BIT(4) +#define BM_IR_MR3 BIT(3) +#define BM_IR_MR2 BIT(2) +#define BM_IR_MR1 BIT(1) +#define BM_IR_MR0 BIT(0) + +#define HW_TCR 0x0010 /* RW. Timer controller */ +/* BM_C*_RST + * Timer Counter and the Prescale Counter are synchronously reset on the + * next positive edge of PCLK. The counters remain reset until TCR[1] is + * returned to zero. */ +#define BM_C3_RST BIT(7) +#define BM_C2_RST BIT(6) +#define BM_C1_RST BIT(5) +#define BM_C0_RST BIT(4) +/* BM_C*_EN + * 1 - Timer Counter and Prescale Counter are enabled for counting + * 0 - counters are disabled */ +#define BM_C3_EN BIT(3) +#define BM_C2_EN BIT(2) +#define BM_C1_EN BIT(1) +#define BM_C0_EN BIT(0) + +#define HW_DIR 0x0020 /* RW. Direction? */ +/* 00 - count up + * 01 - count down + * 10 - ?? 2^n/2 */ +#define BM_DIR_COUNT_UP 0 +#define BM_DIR_COUNT_DOWN 1 +#define BM_DIR0_SHIFT 0 +#define BM_DIR1_SHIFT 4 +#define BM_DIR2_SHIFT 8 +#define BM_DIR3_SHIFT 12 +#define BM_DIR_DEFAULT (BM_DIR_COUNT_UP << BM_DIR0_SHIFT | \ + BM_DIR_COUNT_UP << BM_DIR1_SHIFT | \ + BM_DIR_COUNT_UP << BM_DIR2_SHIFT | \ + BM_DIR_COUNT_UP << BM_DIR3_SHIFT) + +#define HW_TC0 0x0030 /* RO. Timer counter 0 */ +/* HW_TC*. Timer counter owerflow (0xffff.ffff to 0x0000.0000) do not generate + * interrupt. This registers can be used to detect overflow */ +#define HW_TC1 0x0040 +#define HW_TC2 0x0050 +#define HW_TC3 0x0060 + +#define HW_PR 0x0070 /* RW. prescaler */ +#define BM_PR_DISABLE 0 +#define HW_PC 0x0080 /* RO. Prescaler counter */ +#define HW_MCR 0x0090 /* RW. Match control */ +/* enable interrupt on match */ +#define BM_MCR_INT_EN(n) (1 << (n * 3 + 0)) +/* enable TC reset on match */ +#define BM_MCR_RES_EN(n) (1 << (n * 3 + 1)) +/* enable stop TC on match */ +#define BM_MCR_STOP_EN(n) (1 << (n * 3 + 2)) + +#define HW_MR0 0x00a0 /* RW. Match reg */ +#define HW_MR1 0x00b0 +#define HW_MR2 0x00C0 +#define HW_MR3 0x00D0 + +#define HW_CTCR 0x0180 /* Counter control */ +#define BM_CTCR0_SHIFT 0 +#define BM_CTCR1_SHIFT 2 +#define BM_CTCR2_SHIFT 4 +#define BM_CTCR3_SHIFT 6 +#define BM_CTCR_TM 0 /* Timer mode. Every rising PCLK edge. */ +#define BM_CTCR_DEFAULT (BM_CTCR_TM << BM_CTCR0_SHIFT | \ + BM_CTCR_TM << BM_CTCR1_SHIFT | \ + BM_CTCR_TM << BM_CTCR2_SHIFT | \ + BM_CTCR_TM << BM_CTCR3_SHIFT) + +static struct asm9260_timer_priv { + void __iomem *base; + unsigned long ticks_per_jiffy; +} priv; + +static int asm9260_timer_set_next_event(unsigned long delta, + struct clock_event_device *evt) +{ + /* configure match count for TC0 */ + writel_relaxed(delta, priv.base + HW_MR0); + /* enable TC0 */ + writel_relaxed(BM_C0_EN, priv.base + HW_TCR + SET_REG); + return 0; +} + +static inline void __asm9260_timer_shutdown(struct clock_event_device *evt) +{ + /* stop timer0 */ + writel_relaxed(BM_C0_EN, priv.base + HW_TCR + CLR_REG); +} + +static int asm9260_timer_shutdown(struct clock_event_device *evt) +{ + __asm9260_timer_shutdown(evt); + return 0; +} + +static int asm9260_timer_set_oneshot(struct clock_event_device *evt) +{ + __asm9260_timer_shutdown(evt); + + /* enable reset and stop on match */ + writel_relaxed(BM_MCR_RES_EN(0) | BM_MCR_STOP_EN(0), + priv.base + HW_MCR + SET_REG); + return 0; +} + +static int asm9260_timer_set_periodic(struct clock_event_device *evt) +{ + __asm9260_timer_shutdown(evt); + + /* disable reset and stop on match */ + writel_relaxed(BM_MCR_RES_EN(0) | BM_MCR_STOP_EN(0), + priv.base + HW_MCR + CLR_REG); + /* configure match count for TC0 */ + writel_relaxed(priv.ticks_per_jiffy, priv.base + HW_MR0); + /* enable TC0 */ + writel_relaxed(BM_C0_EN, priv.base + HW_TCR + SET_REG); + return 0; +} + +static struct clock_event_device event_dev = { + .name = DRIVER_NAME, + .rating = 200, + .features = CLOCK_EVT_FEAT_PERIODIC | + CLOCK_EVT_FEAT_ONESHOT, + .set_next_event = asm9260_timer_set_next_event, + .set_state_shutdown = asm9260_timer_shutdown, + .set_state_periodic = asm9260_timer_set_periodic, + .set_state_oneshot = asm9260_timer_set_oneshot, + .tick_resume = asm9260_timer_shutdown, +}; + +static irqreturn_t asm9260_timer_interrupt(int irq, void *dev_id) +{ + struct clock_event_device *evt = dev_id; + + evt->event_handler(evt); + + writel_relaxed(BM_IR_MR0, priv.base + HW_IR); + + return IRQ_HANDLED; +} + +/* + * --------------------------------------------------------------------------- + * Timer initialization + * --------------------------------------------------------------------------- + */ +static int __init asm9260_timer_init(struct device_node *np) +{ + int irq; + struct clk *clk; + int ret; + unsigned long rate; + + priv.base = of_io_request_and_map(np, 0, np->name); + if (IS_ERR(priv.base)) { + pr_err("%pOFn: unable to map resource\n", np); + return PTR_ERR(priv.base); + } + + clk = of_clk_get(np, 0); + if (IS_ERR(clk)) { + pr_err("Failed to get clk!\n"); + return PTR_ERR(clk); + } + + ret = clk_prepare_enable(clk); + if (ret) { + pr_err("Failed to enable clk!\n"); + return ret; + } + + irq = irq_of_parse_and_map(np, 0); + ret = request_irq(irq, asm9260_timer_interrupt, IRQF_TIMER, + DRIVER_NAME, &event_dev); + if (ret) { + pr_err("Failed to setup irq!\n"); + clk_disable_unprepare(clk); + return ret; + } + + /* set all timers for count-up */ + writel_relaxed(BM_DIR_DEFAULT, priv.base + HW_DIR); + /* disable divider */ + writel_relaxed(BM_PR_DISABLE, priv.base + HW_PR); + /* make sure all timers use every rising PCLK edge. */ + writel_relaxed(BM_CTCR_DEFAULT, priv.base + HW_CTCR); + /* enable interrupt for TC0 and clean setting for all other lines */ + writel_relaxed(BM_MCR_INT_EN(0) , priv.base + HW_MCR); + + rate = clk_get_rate(clk); + clocksource_mmio_init(priv.base + HW_TC1, DRIVER_NAME, rate, + 200, 32, clocksource_mmio_readl_up); + + /* Seems like we can't use counter without match register even if + * actions for MR are disabled. So, set MR to max value. */ + writel_relaxed(0xffffffff, priv.base + HW_MR1); + /* enable TC1 */ + writel_relaxed(BM_C1_EN, priv.base + HW_TCR + SET_REG); + + priv.ticks_per_jiffy = DIV_ROUND_CLOSEST(rate, HZ); + event_dev.cpumask = cpumask_of(0); + clockevents_config_and_register(&event_dev, rate, 0x2c00, 0xfffffffe); + + return 0; +} +TIMER_OF_DECLARE(asm9260_timer, "alphascale,asm9260-timer", + asm9260_timer_init); |
