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(I'm so sorry!) Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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#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);