diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
---|---|---|
committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/clocksource/timer-fttmr010.c | |
parent | Initial commit. (diff) | |
download | linux-upstream.tar.xz linux-upstream.zip |
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/clocksource/timer-fttmr010.c')
-rw-r--r-- | drivers/clocksource/timer-fttmr010.c | 459 |
1 files changed, 459 insertions, 0 deletions
diff --git a/drivers/clocksource/timer-fttmr010.c b/drivers/clocksource/timer-fttmr010.c new file mode 100644 index 000000000..126fb1f25 --- /dev/null +++ b/drivers/clocksource/timer-fttmr010.c @@ -0,0 +1,459 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Faraday Technology FTTMR010 timer driver + * Copyright (C) 2017 Linus Walleij <linus.walleij@linaro.org> + * + * Based on a rewrite of arch/arm/mach-gemini/timer.c: + * Copyright (C) 2001-2006 Storlink, Corp. + * Copyright (C) 2008-2009 Paulius Zaleckas <paulius.zaleckas@teltonika.lt> + */ +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <linux/clockchips.h> +#include <linux/clocksource.h> +#include <linux/sched_clock.h> +#include <linux/clk.h> +#include <linux/slab.h> +#include <linux/bitops.h> +#include <linux/delay.h> + +/* + * Register definitions common for all the timer variants. + */ +#define TIMER1_COUNT (0x00) +#define TIMER1_LOAD (0x04) +#define TIMER1_MATCH1 (0x08) +#define TIMER1_MATCH2 (0x0c) +#define TIMER2_COUNT (0x10) +#define TIMER2_LOAD (0x14) +#define TIMER2_MATCH1 (0x18) +#define TIMER2_MATCH2 (0x1c) +#define TIMER3_COUNT (0x20) +#define TIMER3_LOAD (0x24) +#define TIMER3_MATCH1 (0x28) +#define TIMER3_MATCH2 (0x2c) +#define TIMER_CR (0x30) + +/* + * Control register set to clear for ast2600 only. + */ +#define AST2600_TIMER_CR_CLR (0x3c) + +/* + * Control register (TMC30) bit fields for fttmr010/gemini/moxart timers. + */ +#define TIMER_1_CR_ENABLE BIT(0) +#define TIMER_1_CR_CLOCK BIT(1) +#define TIMER_1_CR_INT BIT(2) +#define TIMER_2_CR_ENABLE BIT(3) +#define TIMER_2_CR_CLOCK BIT(4) +#define TIMER_2_CR_INT BIT(5) +#define TIMER_3_CR_ENABLE BIT(6) +#define TIMER_3_CR_CLOCK BIT(7) +#define TIMER_3_CR_INT BIT(8) +#define TIMER_1_CR_UPDOWN BIT(9) +#define TIMER_2_CR_UPDOWN BIT(10) +#define TIMER_3_CR_UPDOWN BIT(11) + +/* + * Control register (TMC30) bit fields for aspeed ast2400/ast2500 timers. + * The aspeed timers move bits around in the control register and lacks + * bits for setting the timer to count upwards. + */ +#define TIMER_1_CR_ASPEED_ENABLE BIT(0) +#define TIMER_1_CR_ASPEED_CLOCK BIT(1) +#define TIMER_1_CR_ASPEED_INT BIT(2) +#define TIMER_2_CR_ASPEED_ENABLE BIT(4) +#define TIMER_2_CR_ASPEED_CLOCK BIT(5) +#define TIMER_2_CR_ASPEED_INT BIT(6) +#define TIMER_3_CR_ASPEED_ENABLE BIT(8) +#define TIMER_3_CR_ASPEED_CLOCK BIT(9) +#define TIMER_3_CR_ASPEED_INT BIT(10) + +/* + * Interrupt status/mask register definitions for fttmr010/gemini/moxart + * timers. + * The registers don't exist and they are not needed on aspeed timers + * because: + * - aspeed timer overflow interrupt is controlled by bits in Control + * Register (TMC30). + * - aspeed timers always generate interrupt when either one of the + * Match registers equals to Status register. + */ +#define TIMER_INTR_STATE (0x34) +#define TIMER_INTR_MASK (0x38) +#define TIMER_1_INT_MATCH1 BIT(0) +#define TIMER_1_INT_MATCH2 BIT(1) +#define TIMER_1_INT_OVERFLOW BIT(2) +#define TIMER_2_INT_MATCH1 BIT(3) +#define TIMER_2_INT_MATCH2 BIT(4) +#define TIMER_2_INT_OVERFLOW BIT(5) +#define TIMER_3_INT_MATCH1 BIT(6) +#define TIMER_3_INT_MATCH2 BIT(7) +#define TIMER_3_INT_OVERFLOW BIT(8) +#define TIMER_INT_ALL_MASK 0x1ff + +struct fttmr010 { + void __iomem *base; + unsigned int tick_rate; + bool is_aspeed; + u32 t1_enable_val; + struct clock_event_device clkevt; + int (*timer_shutdown)(struct clock_event_device *evt); +#ifdef CONFIG_ARM + struct delay_timer delay_timer; +#endif +}; + +/* + * A local singleton used by sched_clock and delay timer reads, which are + * fast and stateless + */ +static struct fttmr010 *local_fttmr; + +static inline struct fttmr010 *to_fttmr010(struct clock_event_device *evt) +{ + return container_of(evt, struct fttmr010, clkevt); +} + +static unsigned long fttmr010_read_current_timer_up(void) +{ + return readl(local_fttmr->base + TIMER2_COUNT); +} + +static unsigned long fttmr010_read_current_timer_down(void) +{ + return ~readl(local_fttmr->base + TIMER2_COUNT); +} + +static u64 notrace fttmr010_read_sched_clock_up(void) +{ + return fttmr010_read_current_timer_up(); +} + +static u64 notrace fttmr010_read_sched_clock_down(void) +{ + return fttmr010_read_current_timer_down(); +} + +static int fttmr010_timer_set_next_event(unsigned long cycles, + struct clock_event_device *evt) +{ + struct fttmr010 *fttmr010 = to_fttmr010(evt); + u32 cr; + + /* Stop */ + fttmr010->timer_shutdown(evt); + + if (fttmr010->is_aspeed) { + /* + * ASPEED Timer Controller will load TIMER1_LOAD register + * into TIMER1_COUNT register when the timer is re-enabled. + */ + writel(cycles, fttmr010->base + TIMER1_LOAD); + } else { + /* Setup the match register forward in time */ + cr = readl(fttmr010->base + TIMER1_COUNT); + writel(cr + cycles, fttmr010->base + TIMER1_MATCH1); + } + + /* Start */ + cr = readl(fttmr010->base + TIMER_CR); + cr |= fttmr010->t1_enable_val; + writel(cr, fttmr010->base + TIMER_CR); + + return 0; +} + +static int ast2600_timer_shutdown(struct clock_event_device *evt) +{ + struct fttmr010 *fttmr010 = to_fttmr010(evt); + + /* Stop */ + writel(fttmr010->t1_enable_val, fttmr010->base + AST2600_TIMER_CR_CLR); + + return 0; +} + +static int fttmr010_timer_shutdown(struct clock_event_device *evt) +{ + struct fttmr010 *fttmr010 = to_fttmr010(evt); + u32 cr; + + /* Stop */ + cr = readl(fttmr010->base + TIMER_CR); + cr &= ~fttmr010->t1_enable_val; + writel(cr, fttmr010->base + TIMER_CR); + + return 0; +} + +static int fttmr010_timer_set_oneshot(struct clock_event_device *evt) +{ + struct fttmr010 *fttmr010 = to_fttmr010(evt); + u32 cr; + + /* Stop */ + fttmr010->timer_shutdown(evt); + + /* Setup counter start from 0 or ~0 */ + writel(0, fttmr010->base + TIMER1_COUNT); + if (fttmr010->is_aspeed) { + writel(~0, fttmr010->base + TIMER1_LOAD); + } else { + writel(0, fttmr010->base + TIMER1_LOAD); + + /* Enable interrupt */ + cr = readl(fttmr010->base + TIMER_INTR_MASK); + cr &= ~(TIMER_1_INT_OVERFLOW | TIMER_1_INT_MATCH2); + cr |= TIMER_1_INT_MATCH1; + writel(cr, fttmr010->base + TIMER_INTR_MASK); + } + + return 0; +} + +static int fttmr010_timer_set_periodic(struct clock_event_device *evt) +{ + struct fttmr010 *fttmr010 = to_fttmr010(evt); + u32 period = DIV_ROUND_CLOSEST(fttmr010->tick_rate, HZ); + u32 cr; + + /* Stop */ + fttmr010->timer_shutdown(evt); + + /* Setup timer to fire at 1/HZ intervals. */ + if (fttmr010->is_aspeed) { + writel(period, fttmr010->base + TIMER1_LOAD); + } else { + cr = 0xffffffff - (period - 1); + writel(cr, fttmr010->base + TIMER1_COUNT); + writel(cr, fttmr010->base + TIMER1_LOAD); + + /* Enable interrupt on overflow */ + cr = readl(fttmr010->base + TIMER_INTR_MASK); + cr &= ~(TIMER_1_INT_MATCH1 | TIMER_1_INT_MATCH2); + cr |= TIMER_1_INT_OVERFLOW; + writel(cr, fttmr010->base + TIMER_INTR_MASK); + } + + /* Start the timer */ + cr = readl(fttmr010->base + TIMER_CR); + cr |= fttmr010->t1_enable_val; + writel(cr, fttmr010->base + TIMER_CR); + + return 0; +} + +/* + * IRQ handler for the timer + */ +static irqreturn_t fttmr010_timer_interrupt(int irq, void *dev_id) +{ + struct clock_event_device *evt = dev_id; + + evt->event_handler(evt); + return IRQ_HANDLED; +} + +static irqreturn_t ast2600_timer_interrupt(int irq, void *dev_id) +{ + struct clock_event_device *evt = dev_id; + struct fttmr010 *fttmr010 = to_fttmr010(evt); + + writel(0x1, fttmr010->base + TIMER_INTR_STATE); + + evt->event_handler(evt); + return IRQ_HANDLED; +} + +static int __init fttmr010_common_init(struct device_node *np, + bool is_aspeed, bool is_ast2600) +{ + struct fttmr010 *fttmr010; + int irq; + struct clk *clk; + int ret; + u32 val; + + /* + * These implementations require a clock reference. + * FIXME: we currently only support clocking using PCLK + * and using EXTCLK is not supported in the driver. + */ + clk = of_clk_get_by_name(np, "PCLK"); + if (IS_ERR(clk)) { + pr_err("could not get PCLK\n"); + return PTR_ERR(clk); + } + ret = clk_prepare_enable(clk); + if (ret) { + pr_err("failed to enable PCLK\n"); + return ret; + } + + fttmr010 = kzalloc(sizeof(*fttmr010), GFP_KERNEL); + if (!fttmr010) { + ret = -ENOMEM; + goto out_disable_clock; + } + fttmr010->tick_rate = clk_get_rate(clk); + + fttmr010->base = of_iomap(np, 0); + if (!fttmr010->base) { + pr_err("Can't remap registers\n"); + ret = -ENXIO; + goto out_free; + } + /* IRQ for timer 1 */ + irq = irq_of_parse_and_map(np, 0); + if (irq <= 0) { + pr_err("Can't parse IRQ\n"); + ret = -EINVAL; + goto out_unmap; + } + + /* + * The Aspeed timers move bits around in the control register. + */ + if (is_aspeed) { + fttmr010->t1_enable_val = TIMER_1_CR_ASPEED_ENABLE | + TIMER_1_CR_ASPEED_INT; + fttmr010->is_aspeed = true; + } else { + fttmr010->t1_enable_val = TIMER_1_CR_ENABLE | TIMER_1_CR_INT; + + /* + * Reset the interrupt mask and status + */ + writel(TIMER_INT_ALL_MASK, fttmr010->base + TIMER_INTR_MASK); + writel(0, fttmr010->base + TIMER_INTR_STATE); + } + + /* + * Enable timer 1 count up, timer 2 count up, except on Aspeed, + * where everything just counts down. + */ + if (is_aspeed) + val = TIMER_2_CR_ASPEED_ENABLE; + else { + val = TIMER_2_CR_ENABLE | TIMER_1_CR_UPDOWN | + TIMER_2_CR_UPDOWN; + } + writel(val, fttmr010->base + TIMER_CR); + + /* + * Setup free-running clocksource timer (interrupts + * disabled.) + */ + local_fttmr = fttmr010; + writel(0, fttmr010->base + TIMER2_COUNT); + writel(0, fttmr010->base + TIMER2_MATCH1); + writel(0, fttmr010->base + TIMER2_MATCH2); + + if (fttmr010->is_aspeed) { + writel(~0, fttmr010->base + TIMER2_LOAD); + clocksource_mmio_init(fttmr010->base + TIMER2_COUNT, + "FTTMR010-TIMER2", + fttmr010->tick_rate, + 300, 32, clocksource_mmio_readl_down); + sched_clock_register(fttmr010_read_sched_clock_down, 32, + fttmr010->tick_rate); + } else { + writel(0, fttmr010->base + TIMER2_LOAD); + clocksource_mmio_init(fttmr010->base + TIMER2_COUNT, + "FTTMR010-TIMER2", + fttmr010->tick_rate, + 300, 32, clocksource_mmio_readl_up); + sched_clock_register(fttmr010_read_sched_clock_up, 32, + fttmr010->tick_rate); + } + + /* + * Setup clockevent timer (interrupt-driven) on timer 1. + */ + writel(0, fttmr010->base + TIMER1_COUNT); + writel(0, fttmr010->base + TIMER1_LOAD); + writel(0, fttmr010->base + TIMER1_MATCH1); + writel(0, fttmr010->base + TIMER1_MATCH2); + + if (is_ast2600) { + fttmr010->timer_shutdown = ast2600_timer_shutdown; + ret = request_irq(irq, ast2600_timer_interrupt, + IRQF_TIMER, "FTTMR010-TIMER1", + &fttmr010->clkevt); + } else { + fttmr010->timer_shutdown = fttmr010_timer_shutdown; + ret = request_irq(irq, fttmr010_timer_interrupt, + IRQF_TIMER, "FTTMR010-TIMER1", + &fttmr010->clkevt); + } + if (ret) { + pr_err("FTTMR010-TIMER1 no IRQ\n"); + goto out_unmap; + } + + fttmr010->clkevt.name = "FTTMR010-TIMER1"; + /* Reasonably fast and accurate clock event */ + fttmr010->clkevt.rating = 300; + fttmr010->clkevt.features = CLOCK_EVT_FEAT_PERIODIC | + CLOCK_EVT_FEAT_ONESHOT; + fttmr010->clkevt.set_next_event = fttmr010_timer_set_next_event; + fttmr010->clkevt.set_state_shutdown = fttmr010->timer_shutdown; + fttmr010->clkevt.set_state_periodic = fttmr010_timer_set_periodic; + fttmr010->clkevt.set_state_oneshot = fttmr010_timer_set_oneshot; + fttmr010->clkevt.tick_resume = fttmr010->timer_shutdown; + fttmr010->clkevt.cpumask = cpumask_of(0); + fttmr010->clkevt.irq = irq; + clockevents_config_and_register(&fttmr010->clkevt, + fttmr010->tick_rate, + 1, 0xffffffff); + +#ifdef CONFIG_ARM + /* Also use this timer for delays */ + if (fttmr010->is_aspeed) + fttmr010->delay_timer.read_current_timer = + fttmr010_read_current_timer_down; + else + fttmr010->delay_timer.read_current_timer = + fttmr010_read_current_timer_up; + fttmr010->delay_timer.freq = fttmr010->tick_rate; + register_current_timer_delay(&fttmr010->delay_timer); +#endif + + return 0; + +out_unmap: + iounmap(fttmr010->base); +out_free: + kfree(fttmr010); +out_disable_clock: + clk_disable_unprepare(clk); + + return ret; +} + +static __init int ast2600_timer_init(struct device_node *np) +{ + return fttmr010_common_init(np, true, true); +} + +static __init int aspeed_timer_init(struct device_node *np) +{ + return fttmr010_common_init(np, true, false); +} + +static __init int fttmr010_timer_init(struct device_node *np) +{ + return fttmr010_common_init(np, false, false); +} + +TIMER_OF_DECLARE(fttmr010, "faraday,fttmr010", fttmr010_timer_init); +TIMER_OF_DECLARE(gemini, "cortina,gemini-timer", fttmr010_timer_init); +TIMER_OF_DECLARE(moxart, "moxa,moxart-timer", fttmr010_timer_init); +TIMER_OF_DECLARE(ast2400, "aspeed,ast2400-timer", aspeed_timer_init); +TIMER_OF_DECLARE(ast2500, "aspeed,ast2500-timer", aspeed_timer_init); +TIMER_OF_DECLARE(ast2600, "aspeed,ast2600-timer", ast2600_timer_init); |